gl_backend.c

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#include "quakedef.h"
#include "cl_collision.h"
 
#define MAX_RENDERTARGETS 4
 
cvar_t gl_debug = {CF_CLIENT, "gl_debug", "0", "enables OpenGL 4.3 debug output, 0 = off, 1 = HIGH severity only, 2 = also MEDIUM severity, 3 = also LOW severity messages.  (note: enabling may not take effect until vid_restart on some drivers, and only X11 and Windows are known to support the debug context)"};
cvar_t gl_paranoid = {CF_CLIENT, "gl_paranoid", "0", "enables OpenGL error checking and other tests"};
cvar_t gl_printcheckerror = {CF_CLIENT, "gl_printcheckerror", "0", "prints all OpenGL error checks, useful to identify location of driver crashes"};
 
cvar_t r_render = {CF_CLIENT, "r_render", "1", "enables rendering 3D views (you want this on!)"};
cvar_t r_renderview = {CF_CLIENT, "r_renderview", "1", "enables rendering 3D views (you want this on!)"};
cvar_t r_waterwarp = {CF_CLIENT | CF_ARCHIVE, "r_waterwarp", "1", "warp view while underwater"};
#ifdef USE_GLES2
cvar_t gl_polyblend = {CF_CLIENT | CF_ARCHIVE, "gl_polyblend", "0", "tints view while underwater, hurt, etc"};
#else
cvar_t gl_polyblend = {CF_CLIENT | CF_ARCHIVE, "gl_polyblend", "1", "tints view while underwater, hurt, etc"};
#endif
 
cvar_t v_flipped = {CF_CLIENT, "v_flipped", "0", "mirror the screen (poor man's left handed mode)"};
qbool v_flipped_state = false;
 
r_viewport_t gl_viewport;
matrix4x4_t gl_modelmatrix;
matrix4x4_t gl_viewmatrix;
matrix4x4_t gl_modelviewmatrix;
matrix4x4_t gl_projectionmatrix;
matrix4x4_t gl_modelviewprojectionmatrix;
float gl_modelview16f[16];
float gl_modelviewprojection16f[16];
qbool gl_modelmatrixchanged;
 
#ifdef DEBUGGL
void GL_PrintError(GLenum errornumber, const char *filename, unsigned int linenumber)
{
    switch(errornumber)
    {
#ifdef GL_INVALID_ENUM
    case GL_INVALID_ENUM:
        Con_Printf(CON_ERROR "GL_INVALID_ENUM at %s:%i\n", filename, linenumber);
        break;
#endif
#ifdef GL_INVALID_VALUE
    case GL_INVALID_VALUE:
        Con_Printf(CON_ERROR "GL_INVALID_VALUE at %s:%i\n", filename, linenumber);
        break;
#endif
#ifdef GL_INVALID_OPERATION
    case GL_INVALID_OPERATION:
        Con_Printf(CON_ERROR "GL_INVALID_OPERATION at %s:%i\n", filename, linenumber);
        break;
#endif
#ifdef GL_STACK_OVERFLOW
    case GL_STACK_OVERFLOW:
        Con_Printf(CON_ERROR "GL_STACK_OVERFLOW at %s:%i\n", filename, linenumber);
        break;
#endif
#ifdef GL_STACK_UNDERFLOW
    case GL_STACK_UNDERFLOW:
        Con_Printf(CON_ERROR "GL_STACK_UNDERFLOW at %s:%i\n", filename, linenumber);
        break;
#endif
#ifdef GL_OUT_OF_MEMORY
    case GL_OUT_OF_MEMORY:
        Con_Printf(CON_ERROR "GL_OUT_OF_MEMORY at %s:%i\n", filename, linenumber);
        break;
#endif
#ifdef GL_INVALID_FRAMEBUFFER_OPERATION
    case GL_INVALID_FRAMEBUFFER_OPERATION:
        Con_Printf(CON_ERROR "GL_INVALID_FRAMEBUFFER_OPERATION at %s:%i\n", filename, linenumber);
        break;
#endif
    default:
        Con_Printf(CON_ERROR "GL UNKNOWN (%i) at %s:%i\n", errornumber, filename, linenumber);
        break;
    }
}
#endif // DEBUGGL
 
static void GLAPIENTRY GL_DebugOutputCallback(GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar* message, const GLvoid* userParam)
{
    const char *sev = "ENUM?", *typ = "ENUM?", *src = "ENUM?", *col = "";
    switch (severity)
    {
    case GL_DEBUG_SEVERITY_LOW_ARB: sev = "LOW"; break;
    case GL_DEBUG_SEVERITY_MEDIUM_ARB: sev = "MED"; col = CON_WARN; break;
    case GL_DEBUG_SEVERITY_HIGH_ARB: sev = "HIGH"; col = CON_ERROR; break;
    }
    switch (type)
    {
    case GL_DEBUG_TYPE_ERROR_ARB: typ = "ERROR"; col = CON_ERROR; break;
    case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR_ARB: typ = "DEPRECATED"; break;
    case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR_ARB: typ = "UNDEFINED"; break;
    case GL_DEBUG_TYPE_PORTABILITY_ARB: typ = "PORTABILITY"; break;
    case GL_DEBUG_TYPE_PERFORMANCE_ARB: typ = "PERFORMANCE"; break;
    case GL_DEBUG_TYPE_OTHER_ARB: typ = "OTHER"; break;
    }
    switch (source)
    {
    case GL_DEBUG_SOURCE_API_ARB: src = "API"; break;
    case GL_DEBUG_SOURCE_SHADER_COMPILER_ARB: src = "SHADER"; break;
    case GL_DEBUG_SOURCE_WINDOW_SYSTEM_ARB: src = "WIN"; break;
    case GL_DEBUG_SOURCE_THIRD_PARTY_ARB: src = "THIRDPARTY"; break;
    case GL_DEBUG_SOURCE_APPLICATION_ARB: src = "APP"; break;
    case GL_DEBUG_SOURCE_OTHER_ARB: src = "OTHER"; break;
    }
    Con_Printf("gl_debug: %s%s %s %s: %u: %s\n", col, sev, typ, src, (unsigned int)id, message);
}
 
#define BACKENDACTIVECHECK if (!gl_state.active) Sys_Error("GL backend function called when backend is not active");
 
void SCR_ScreenShot_f(cmd_state_t *cmd);
 
typedef struct gltextureunit_s
{
    int pointer_texcoord_components;
    int pointer_texcoord_gltype;
    size_t pointer_texcoord_stride;
    const void *pointer_texcoord_pointer;
    const r_meshbuffer_t *pointer_texcoord_vertexbuffer;
    size_t pointer_texcoord_offset;
 
    rtexture_t *texture;
    int t2d, t3d, tcubemap;
    int arrayenabled;
}
gltextureunit_t;
 
typedef struct gl_state_s
{
    int cullface;
    int cullfaceenable;
    int blendfunc1;
    int blendfunc2;
    qbool blend;
    GLboolean depthmask;
    int colormask; // stored as bottom 4 bits: r g b a (3 2 1 0 order)
    int depthtest;
    int depthfunc;
    float depthrange[2];
    float polygonoffset[2];
    qbool alphatocoverage;
    int scissortest;
    unsigned int unit;
    gltextureunit_t units[MAX_TEXTUREUNITS];
    float color4f[4];
    int lockrange_first;
    int lockrange_count;
    int vertexbufferobject;
    int elementbufferobject;
    int uniformbufferobject;
    int framebufferobject;
    int defaultframebufferobject; // deal with platforms that use a non-zero default fbo
    qbool pointer_color_enabled;
 
    // GL3.2 Core requires that we have a GL_VERTEX_ARRAY_OBJECT, but... just one.
    unsigned int defaultvao;
 
    int pointer_vertex_components;
    int pointer_vertex_gltype;
    size_t pointer_vertex_stride;
    const void *pointer_vertex_pointer;
    const r_meshbuffer_t *pointer_vertex_vertexbuffer;
    size_t pointer_vertex_offset;
 
    int pointer_color_components;
    int pointer_color_gltype;
    size_t pointer_color_stride;
    const void *pointer_color_pointer;
    const r_meshbuffer_t *pointer_color_vertexbuffer;
    size_t pointer_color_offset;
 
    void *preparevertices_tempdata;
    size_t preparevertices_tempdatamaxsize;
    int preparevertices_numvertices;
 
    memexpandablearray_t meshbufferarray;
 
    qbool active;
}
gl_state_t;
 
static gl_state_t gl_state;
 
 
/*
note: here's strip order for a terrain row:
0--1--2--3--4
|\ |\ |\ |\ |
| \| \| \| \|
A--B--C--D--E
clockwise
 
A0B, 01B, B1C, 12C, C2D, 23D, D3E, 34E
 
*elements++ = i + row;
*elements++ = i;
*elements++ = i + row + 1;
*elements++ = i;
*elements++ = i + 1;
*elements++ = i + row + 1;
 
 
for (y = 0;y < rows - 1;y++)
{
    for (x = 0;x < columns - 1;x++)
    {
        i = y * rows + x;
        *elements++ = i + columns;
        *elements++ = i;
        *elements++ = i + columns + 1;
        *elements++ = i;
        *elements++ = i + 1;
        *elements++ = i + columns + 1;
    }
}
 
alternative:
0--1--2--3--4
| /| /|\ | /|
|/ |/ | \|/ |
A--B--C--D--E
counterclockwise
 
for (y = 0;y < rows - 1;y++)
{
    for (x = 0;x < columns - 1;x++)
    {
        i = y * rows + x;
        *elements++ = i;
        *elements++ = i + columns;
        *elements++ = i + columns + 1;
        *elements++ = i + columns;
        *elements++ = i + columns + 1;
        *elements++ = i + 1;
    }
}
*/
 
int polygonelement3i[(POLYGONELEMENTS_MAXPOINTS-2)*3];
unsigned short polygonelement3s[(POLYGONELEMENTS_MAXPOINTS-2)*3];
int quadelement3i[QUADELEMENTS_MAXQUADS*6];
unsigned short quadelement3s[QUADELEMENTS_MAXQUADS*6];
 
static void GL_VBOStats_f(cmd_state_t *cmd)
{
    GL_Mesh_ListVBOs(true);
}
 
static void GL_Backend_ResetState(void);
 
static void gl_backend_start(void)
{
    memset(&gl_state, 0, sizeof(gl_state));
 
    Mem_ExpandableArray_NewArray(&gl_state.meshbufferarray, r_main_mempool, sizeof(r_meshbuffer_t), 128);
 
    Con_Printf("OpenGL backend started\n");
 
    CHECKGLERROR
 
    switch(vid.renderpath)
    {
#ifndef USE_GLES2
    case RENDERPATH_GL32:
        // GL3.2 Core requires that we have a VAO bound - but using more than one has no performance benefit so this is just placeholder
        qglGenVertexArrays(1, &gl_state.defaultvao);
        qglBindVertexArray(gl_state.defaultvao);
        // fall through
#endif //USE_GLES2
    case RENDERPATH_GLES2:
        // fetch current fbo here (default fbo is not 0 on some GLES devices)
        CHECKGLERROR
        qglGetIntegerv(GL_FRAMEBUFFER_BINDING, &gl_state.defaultframebufferobject);CHECKGLERROR
        break;
    }
 
    GL_Backend_ResetState();
}
 
static void gl_backend_shutdown(void)
{
    Con_Print("OpenGL backend shutting down\n");
 
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        break;
    }
 
    if (gl_state.preparevertices_tempdata)
        Mem_Free(gl_state.preparevertices_tempdata);
 
    Mem_ExpandableArray_FreeArray(&gl_state.meshbufferarray);
 
    memset(&gl_state, 0, sizeof(gl_state));
}
 
static void gl_backend_newmap(void)
{
}
 
static void gl_backend_devicelost(void)
{
    int i, endindex;
    r_meshbuffer_t *buffer;
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        break;
    }
    endindex = (int)Mem_ExpandableArray_IndexRange(&gl_state.meshbufferarray);
    for (i = 0;i < endindex;i++)
    {
        buffer = (r_meshbuffer_t *) Mem_ExpandableArray_RecordAtIndex(&gl_state.meshbufferarray, i);
        if (!buffer || !buffer->isdynamic)
            continue;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            break;
        }
    }
}
 
static void gl_backend_devicerestored(void)
{
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        break;
    }
}
 
void gl_backend_init(void)
{
    int i;
 
    for (i = 0;i < POLYGONELEMENTS_MAXPOINTS - 2;i++)
    {
        polygonelement3s[i * 3 + 0] = 0;
        polygonelement3s[i * 3 + 1] = i + 1;
        polygonelement3s[i * 3 + 2] = i + 2;
    }
    // elements for rendering a series of quads as triangles
    for (i = 0;i < QUADELEMENTS_MAXQUADS;i++)
    {
        quadelement3s[i * 6 + 0] = i * 4;
        quadelement3s[i * 6 + 1] = i * 4 + 1;
        quadelement3s[i * 6 + 2] = i * 4 + 2;
        quadelement3s[i * 6 + 3] = i * 4;
        quadelement3s[i * 6 + 4] = i * 4 + 2;
        quadelement3s[i * 6 + 5] = i * 4 + 3;
    }
 
    for (i = 0;i < (POLYGONELEMENTS_MAXPOINTS - 2)*3;i++)
        polygonelement3i[i] = polygonelement3s[i];
    for (i = 0;i < QUADELEMENTS_MAXQUADS*6;i++)
        quadelement3i[i] = quadelement3s[i];
 
    Cvar_RegisterVariable(&r_render);
    Cvar_RegisterVariable(&r_renderview);
    Cvar_RegisterVariable(&r_waterwarp);
    Cvar_RegisterVariable(&gl_polyblend);
    Cvar_RegisterVariable(&v_flipped);
    Cvar_RegisterVariable(&gl_debug);
    Cvar_RegisterVariable(&gl_paranoid);
#ifdef DEBUGGL // gl_printcheckerror does nothing in normal builds
    Cvar_RegisterVariable(&gl_printcheckerror);
#endif
 
    Cmd_AddCommand(CF_CLIENT, "gl_vbostats", GL_VBOStats_f, "prints a list of all buffer objects (vertex data and triangle elements) and total video memory used by them");
 
    R_RegisterModule("GL_Backend", gl_backend_start, gl_backend_shutdown, gl_backend_newmap, gl_backend_devicelost, gl_backend_devicerestored);
}
 
void GL_SetMirrorState(qbool state);
 
void R_Viewport_TransformToScreen(const r_viewport_t *v, const vec4_t in, vec4_t out)
{
    vec4_t temp;
    float iw;
    Matrix4x4_Transform4 (&v->viewmatrix, in, temp);
    Matrix4x4_Transform4 (&v->projectmatrix, temp, out);
    iw = 1.0f / out[3];
    out[0] = v->x + (out[0] * iw + 1.0f) * v->width * 0.5f;
 
    // for an odd reason, inverting this is wrong for R_Shadow_ScissorForBBox (we then get badly scissored lights)
    //out[1] = v->y + v->height - (out[1] * iw + 1.0f) * v->height * 0.5f;
    out[1] = v->y + (out[1] * iw + 1.0f) * v->height * 0.5f;
 
    out[2] = v->z + (out[2] * iw + 1.0f) * v->depth * 0.5f;
}
 
void GL_Finish(void)
{
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
        qglFinish();CHECKGLERROR
        break;
    }
}
 
static int bboxedges[12][2] =
{
    // top
    {0, 1}, // +X
    {0, 2}, // +Y
    {1, 3}, // Y, +X
    {2, 3}, // X, +Y
    // bottom
    {4, 5}, // +X
    {4, 6}, // +Y
    {5, 7}, // Y, +X
    {6, 7}, // X, +Y
    // verticals
    {0, 4}, // +Z
    {1, 5}, // X, +Z
    {2, 6}, // Y, +Z
    {3, 7}, // XY, +Z
};
 
qbool R_ScissorForBBox(const float *mins, const float *maxs, int *scissor)
{
    int i, ix1, iy1, ix2, iy2;
    float x1, y1, x2, y2;
    vec4_t v, v2;
    float vertex[20][3];
    int j, k;
    vec4_t plane4f;
    int numvertices;
    float corner[8][4];
    float dist[8];
    int sign[8];
    float f;
 
    scissor[0] = r_refdef.view.viewport.x;
    scissor[1] = r_refdef.view.viewport.y;
    scissor[2] = r_refdef.view.viewport.width;
    scissor[3] = r_refdef.view.viewport.height;
 
    // if view is inside the box, just say yes it's visible
    if (BoxesOverlap(r_refdef.view.origin, r_refdef.view.origin, mins, maxs))
        return false;
 
    // transform all corners that are infront of the nearclip plane
    VectorNegate(r_refdef.view.frustum[4].normal, plane4f);
    plane4f[3] = r_refdef.view.frustum[4].dist;
    numvertices = 0;
    for (i = 0;i < 8;i++)
    {
        Vector4Set(corner[i], (i & 1) ? maxs[0] : mins[0], (i & 2) ? maxs[1] : mins[1], (i & 4) ? maxs[2] : mins[2], 1);
        dist[i] = DotProduct4(corner[i], plane4f);
        sign[i] = dist[i] > 0;
        if (!sign[i])
        {
            VectorCopy(corner[i], vertex[numvertices]);
            numvertices++;
        }
    }
    // if some points are behind the nearclip, add clipped edge points to make
    // sure that the scissor boundary is complete
    if (numvertices > 0 && numvertices < 8)
    {
        // add clipped edge points
        for (i = 0;i < 12;i++)
        {
            j = bboxedges[i][0];
            k = bboxedges[i][1];
            if (sign[j] != sign[k])
            {
                f = dist[j] / (dist[j] - dist[k]);
                VectorLerp(corner[j], f, corner[k], vertex[numvertices]);
                numvertices++;
            }
        }
    }
 
    // if we have no points to check, it is behind the view plane
    if (!numvertices)
        return true;
 
    // if we have some points to transform, check what screen area is covered
    x1 = y1 = x2 = y2 = 0;
    v[3] = 1.0f;
    //Con_Printf("%i vertices to transform...\n", numvertices);
    for (i = 0;i < numvertices;i++)
    {
        VectorCopy(vertex[i], v);
        R_Viewport_TransformToScreen(&r_refdef.view.viewport, v, v2);
        //Con_Printf("%.3f %.3f %.3f %.3f transformed to %.3f %.3f %.3f %.3f\n", v[0], v[1], v[2], v[3], v2[0], v2[1], v2[2], v2[3]);
        if (i)
        {
            if (x1 > v2[0]) x1 = v2[0];
            if (x2 < v2[0]) x2 = v2[0];
            if (y1 > v2[1]) y1 = v2[1];
            if (y2 < v2[1]) y2 = v2[1];
        }
        else
        {
            x1 = x2 = v2[0];
            y1 = y2 = v2[1];
        }
    }
 
    // now convert the scissor rectangle to integer screen coordinates
    ix1 = (int)(x1 - 1.0f);
    //iy1 = vid.height - (int)(y2 - 1.0f);
    //iy1 = r_refdef.view.viewport.width + 2 * r_refdef.view.viewport.x - (int)(y2 - 1.0f);
    iy1 = (int)(y1 - 1.0f);
    ix2 = (int)(x2 + 1.0f);
    //iy2 = vid.height - (int)(y1 + 1.0f);
    //iy2 = r_refdef.view.viewport.height + 2 * r_refdef.view.viewport.y - (int)(y1 + 1.0f);
    iy2 = (int)(y2 + 1.0f);
    //Con_Printf("%f %f %f %f\n", x1, y1, x2, y2);
 
    // clamp it to the screen
    if (ix1 < r_refdef.view.viewport.x) ix1 = r_refdef.view.viewport.x;
    if (iy1 < r_refdef.view.viewport.y) iy1 = r_refdef.view.viewport.y;
    if (ix2 > r_refdef.view.viewport.x + r_refdef.view.viewport.width) ix2 = r_refdef.view.viewport.x + r_refdef.view.viewport.width;
    if (iy2 > r_refdef.view.viewport.y + r_refdef.view.viewport.height) iy2 = r_refdef.view.viewport.y + r_refdef.view.viewport.height;
 
    // if it is inside out, it's not visible
    if (ix2 <= ix1 || iy2 <= iy1)
        return true;
 
    // the light area is visible, set up the scissor rectangle
    scissor[0] = ix1;
    scissor[1] = iy1;
    scissor[2] = ix2 - ix1;
    scissor[3] = iy2 - iy1;
 
    // D3D Y coordinate is top to bottom, OpenGL is bottom to top, fix the D3D one
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        break;
    }
 
    return false;
}
 
 
static void R_Viewport_ApplyNearClipPlaneFloatGL(const r_viewport_t *v, float *m, float normalx, float normaly, float normalz, float dist)
{
    float q[4];
    float d;
    float clipPlane[4], v3[3], v4[3];
    float normal[3];
 
    // This is inspired by Oblique Depth Projection from http://www.terathon.com/code/oblique.php
 
    VectorSet(normal, normalx, normaly, normalz);
    Matrix4x4_Transform3x3(&v->viewmatrix, normal, clipPlane);
    VectorScale(normal, -dist, v3);
    Matrix4x4_Transform(&v->viewmatrix, v3, v4);
    // FIXME: LadyHavoc: I think this can be done more efficiently somehow but I can't remember the technique
    clipPlane[3] = -DotProduct(v4, clipPlane);
 
    // Calculate the clip-space corner point opposite the clipping plane
    // as (sgn(clipPlane.x), sgn(clipPlane.y), 1, 1) and
    // transform it into camera space by multiplying it
    // by the inverse of the projection matrix
    q[0] = ((clipPlane[0] < 0.0f ? -1.0f : clipPlane[0] > 0.0f ? 1.0f : 0.0f) + m[8]) / m[0];
    q[1] = ((clipPlane[1] < 0.0f ? -1.0f : clipPlane[1] > 0.0f ? 1.0f : 0.0f) + m[9]) / m[5];
    q[2] = -1.0f;
    q[3] = (1.0f + m[10]) / m[14];
 
    // Calculate the scaled plane vector
    d = 2.0f / DotProduct4(clipPlane, q);
 
    // Replace the third row of the projection matrix
    m[2] = clipPlane[0] * d;
    m[6] = clipPlane[1] * d;
    m[10] = clipPlane[2] * d + 1.0f;
    m[14] = clipPlane[3] * d;
}
 
void R_Viewport_InitOrtho(r_viewport_t *v, const matrix4x4_t *cameramatrix, int x, int y, int width, int height, float x1, float y1, float x2, float y2, float nearclip, float farclip, const float *nearplane)
{
    float left = x1, right = x2, bottom = y2, top = y1, zNear = nearclip, zFar = farclip;
    float m[16];
    memset(v, 0, sizeof(*v));
    v->type = R_VIEWPORTTYPE_ORTHO;
    v->cameramatrix = *cameramatrix;
    v->x = x;
    v->y = y;
    v->z = 0;
    v->width = width;
    v->height = height;
    v->depth = 1;
    memset(m, 0, sizeof(m));
    m[0]  = 2/(right - left);
    m[5]  = 2/(top - bottom);
    m[10] = -2/(zFar - zNear);
    m[12] = - (right + left)/(right - left);
    m[13] = - (top + bottom)/(top - bottom);
    m[14] = - (zFar + zNear)/(zFar - zNear);
    m[15] = 1;
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        break;
    }
    v->screentodepth[0] = -farclip / (farclip - nearclip);
    v->screentodepth[1] = farclip * nearclip / (farclip - nearclip);
 
    Matrix4x4_Invert_Full(&v->viewmatrix, &v->cameramatrix);
 
    if (nearplane)
        R_Viewport_ApplyNearClipPlaneFloatGL(v, m, nearplane[0], nearplane[1], nearplane[2], nearplane[3]);
 
    Matrix4x4_FromArrayFloatGL(&v->projectmatrix, m);
 
#if 0
    {
        vec4_t test1;
        vec4_t test2;
        Vector4Set(test1, (x1+x2)*0.5f, (y1+y2)*0.5f, 0.0f, 1.0f);
        R_Viewport_TransformToScreen(v, test1, test2);
        Con_Printf("%f %f %f -> %f %f %f\n", test1[0], test1[1], test1[2], test2[0], test2[1], test2[2]);
    }
#endif
}
 
void R_Viewport_InitOrtho3D(r_viewport_t *v, const matrix4x4_t *cameramatrix, int x, int y, int width, int height, float frustumx, float frustumy, float nearclip, float farclip, const float *nearplane)
{
    matrix4x4_t tempmatrix, basematrix;
    float m[16];
    memset(v, 0, sizeof(*v));
 
    v->type = R_VIEWPORTTYPE_PERSPECTIVE;
    v->cameramatrix = *cameramatrix;
    v->x = x;
    v->y = y;
    v->z = 0;
    v->width = width;
    v->height = height;
    v->depth = 1;
    memset(m, 0, sizeof(m));
    m[0]  = 1.0 / frustumx;
    m[5]  = 1.0 / frustumy;
    m[10] = -2 / (farclip - nearclip);
    m[14] = -(farclip + nearclip) / (farclip - nearclip);
    m[15] = 1;
    v->screentodepth[0] = -farclip / (farclip - nearclip);
    v->screentodepth[1] = farclip * nearclip / (farclip - nearclip);
 
    Matrix4x4_Invert_Full(&tempmatrix, &v->cameramatrix);
    Matrix4x4_CreateRotate(&basematrix, -90, 1, 0, 0);
    Matrix4x4_ConcatRotate(&basematrix, 90, 0, 0, 1);
    Matrix4x4_Concat(&v->viewmatrix, &basematrix, &tempmatrix);
 
    if (nearplane)
        R_Viewport_ApplyNearClipPlaneFloatGL(v, m, nearplane[0], nearplane[1], nearplane[2], nearplane[3]);
 
    if(v_flipped.integer)
    {
        m[0] = -m[0];
        m[4] = -m[4];
        m[8] = -m[8];
        m[12] = -m[12];
    }
 
    Matrix4x4_FromArrayFloatGL(&v->projectmatrix, m);
}
 
void R_Viewport_InitPerspective(r_viewport_t *v, const matrix4x4_t *cameramatrix, int x, int y, int width, int height, float frustumx, float frustumy, float nearclip, float farclip, const float *nearplane)
{
    matrix4x4_t tempmatrix, basematrix;
    float m[16];
    memset(v, 0, sizeof(*v));
 
    v->type = R_VIEWPORTTYPE_PERSPECTIVE;
    v->cameramatrix = *cameramatrix;
    v->x = x;
    v->y = y;
    v->z = 0;
    v->width = width;
    v->height = height;
    v->depth = 1;
    memset(m, 0, sizeof(m));
    m[0]  = 1.0 / frustumx;
    m[5]  = 1.0 / frustumy;
    m[10] = -(farclip + nearclip) / (farclip - nearclip);
    m[11] = -1;
    m[14] = -2 * nearclip * farclip / (farclip - nearclip);
    v->screentodepth[0] = -farclip / (farclip - nearclip);
    v->screentodepth[1] = farclip * nearclip / (farclip - nearclip);
 
    Matrix4x4_Invert_Full(&tempmatrix, &v->cameramatrix);
    Matrix4x4_CreateRotate(&basematrix, -90, 1, 0, 0);
    Matrix4x4_ConcatRotate(&basematrix, 90, 0, 0, 1);
    Matrix4x4_Concat(&v->viewmatrix, &basematrix, &tempmatrix);
 
    if (nearplane)
        R_Viewport_ApplyNearClipPlaneFloatGL(v, m, nearplane[0], nearplane[1], nearplane[2], nearplane[3]);
 
    if(v_flipped.integer)
    {
        m[0] = -m[0];
        m[4] = -m[4];
        m[8] = -m[8];
        m[12] = -m[12];
    }
 
    Matrix4x4_FromArrayFloatGL(&v->projectmatrix, m);
}
 
void R_Viewport_InitPerspectiveInfinite(r_viewport_t *v, const matrix4x4_t *cameramatrix, int x, int y, int width, int height, float frustumx, float frustumy, float nearclip, const float *nearplane)
{
    matrix4x4_t tempmatrix, basematrix;
    const float nudge = 1.0 - 1.0 / (1<<23);
    float m[16];
    memset(v, 0, sizeof(*v));
 
    v->type = R_VIEWPORTTYPE_PERSPECTIVE_INFINITEFARCLIP;
    v->cameramatrix = *cameramatrix;
    v->x = x;
    v->y = y;
    v->z = 0;
    v->width = width;
    v->height = height;
    v->depth = 1;
    memset(m, 0, sizeof(m));
    m[ 0] = 1.0 / frustumx;
    m[ 5] = 1.0 / frustumy;
    m[10] = -nudge;
    m[11] = -1;
    m[14] = -2 * nearclip * nudge;
    v->screentodepth[0] = (m[10] + 1) * 0.5 - 1;
    v->screentodepth[1] = m[14] * -0.5;
 
    Matrix4x4_Invert_Full(&tempmatrix, &v->cameramatrix);
    Matrix4x4_CreateRotate(&basematrix, -90, 1, 0, 0);
    Matrix4x4_ConcatRotate(&basematrix, 90, 0, 0, 1);
    Matrix4x4_Concat(&v->viewmatrix, &basematrix, &tempmatrix);
 
    if (nearplane)
        R_Viewport_ApplyNearClipPlaneFloatGL(v, m, nearplane[0], nearplane[1], nearplane[2], nearplane[3]);
 
    if(v_flipped.integer)
    {
        m[0] = -m[0];
        m[4] = -m[4];
        m[8] = -m[8];
        m[12] = -m[12];
    }
 
    Matrix4x4_FromArrayFloatGL(&v->projectmatrix, m);
}
 
float cubeviewmatrix[6][16] =
{
    // standard cubemap projections
    { // +X
         0, 0,-1, 0,
         0,-1, 0, 0,
        -1, 0, 0, 0,
         0, 0, 0, 1,
    },
    { // -X
         0, 0, 1, 0,
         0,-1, 0, 0,
         1, 0, 0, 0,
         0, 0, 0, 1,
    },
    { // +Y
         1, 0, 0, 0,
         0, 0,-1, 0,
         0, 1, 0, 0,
         0, 0, 0, 1,
    },
    { // -Y
         1, 0, 0, 0,
         0, 0, 1, 0,
         0,-1, 0, 0,
         0, 0, 0, 1,
    },
    { // +Z
         1, 0, 0, 0,
         0,-1, 0, 0,
         0, 0,-1, 0,
         0, 0, 0, 1,
    },
    { // -Z
        -1, 0, 0, 0,
         0,-1, 0, 0,
         0, 0, 1, 0,
         0, 0, 0, 1,
    },
};
float rectviewmatrix[6][16] =
{
    // sign-preserving cubemap projections
    { // +X
         0, 0,-1, 0,
         0, 1, 0, 0,
         1, 0, 0, 0,
         0, 0, 0, 1,
    },
    { // -X
         0, 0, 1, 0,
         0, 1, 0, 0,
         1, 0, 0, 0,
         0, 0, 0, 1,
    },
    { // +Y
         1, 0, 0, 0,
         0, 0,-1, 0,
         0, 1, 0, 0,
         0, 0, 0, 1,
    },
    { // -Y
         1, 0, 0, 0,
         0, 0, 1, 0,
         0, 1, 0, 0,
         0, 0, 0, 1,
    },
    { // +Z
         1, 0, 0, 0,
         0, 1, 0, 0,
         0, 0,-1, 0,
         0, 0, 0, 1,
    },
    { // -Z
         1, 0, 0, 0,
         0, 1, 0, 0,
         0, 0, 1, 0,
         0, 0, 0, 1,
    },
};
 
void R_Viewport_InitCubeSideView(r_viewport_t *v, const matrix4x4_t *cameramatrix, int side, int size, float nearclip, float farclip, const float *nearplane)
{
    matrix4x4_t tempmatrix, basematrix;
    float m[16];
    memset(v, 0, sizeof(*v));
    v->type = R_VIEWPORTTYPE_PERSPECTIVECUBESIDE;
    v->cameramatrix = *cameramatrix;
    v->width = size;
    v->height = size;
    v->depth = 1;
    memset(m, 0, sizeof(m));
    m[0] = m[5] = 1.0f;
    m[10] = -(farclip + nearclip) / (farclip - nearclip);
    m[11] = -1;
    m[14] = -2 * nearclip * farclip / (farclip - nearclip);
 
    Matrix4x4_FromArrayFloatGL(&basematrix, cubeviewmatrix[side]);
    Matrix4x4_Invert_Full(&tempmatrix, &v->cameramatrix);
    Matrix4x4_Concat(&v->viewmatrix, &basematrix, &tempmatrix);
 
    if (nearplane)
        R_Viewport_ApplyNearClipPlaneFloatGL(v, m, nearplane[0], nearplane[1], nearplane[2], nearplane[3]);
 
    Matrix4x4_FromArrayFloatGL(&v->projectmatrix, m);
}
 
void R_Viewport_InitRectSideView(r_viewport_t *v, const matrix4x4_t *cameramatrix, int side, int size, int border, float nearclip, float farclip, const float *nearplane, int offsetx, int offsety)
{
    matrix4x4_t tempmatrix, basematrix;
    float m[16];
    memset(v, 0, sizeof(*v));
    v->type = R_VIEWPORTTYPE_PERSPECTIVECUBESIDE;
    v->cameramatrix = *cameramatrix;
    v->x = offsetx + (side & 1) * size;
    v->y = offsety + (side >> 1) * size;
    v->width = size;
    v->height = size;
    v->depth = 1;
    memset(m, 0, sizeof(m));
    m[0] = m[5] = 1.0f * ((float)size - border) / size;
    m[10] = -(farclip + nearclip) / (farclip - nearclip);
    m[11] = -1;
    m[14] = -2 * nearclip * farclip / (farclip - nearclip);
 
    Matrix4x4_FromArrayFloatGL(&basematrix, rectviewmatrix[side]);
    Matrix4x4_Invert_Full(&tempmatrix, &v->cameramatrix);
    Matrix4x4_Concat(&v->viewmatrix, &basematrix, &tempmatrix);
 
    if (nearplane)
        R_Viewport_ApplyNearClipPlaneFloatGL(v, m, nearplane[0], nearplane[1], nearplane[2], nearplane[3]);
 
    Matrix4x4_FromArrayFloatGL(&v->projectmatrix, m);
}
 
void R_SetViewport(const r_viewport_t *v)
{
    gl_viewport = *v;
 
    // FIXME: v_flipped_state is evil, this probably breaks somewhere
    GL_SetMirrorState(v_flipped.integer && (v->type == R_VIEWPORTTYPE_PERSPECTIVE || v->type == R_VIEWPORTTYPE_PERSPECTIVE_INFINITEFARCLIP));
 
    // copy over the matrices to our state
    gl_viewmatrix = v->viewmatrix;
    gl_projectionmatrix = v->projectmatrix;
 
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
        qglViewport(v->x, v->y, v->width, v->height);CHECKGLERROR
        break;
    }
 
    // force an update of the derived matrices
    gl_modelmatrixchanged = true;
    R_EntityMatrix(&gl_modelmatrix);
}
 
void R_GetViewport(r_viewport_t *v)
{
    *v = gl_viewport;
}
 
static void GL_BindVBO(int bufferobject)
{
    if (gl_state.vertexbufferobject != bufferobject)
    {
        gl_state.vertexbufferobject = bufferobject;
        CHECKGLERROR
        qglBindBuffer(GL_ARRAY_BUFFER, bufferobject);CHECKGLERROR
    }
}
 
static void GL_BindEBO(int bufferobject)
{
    if (gl_state.elementbufferobject != bufferobject)
    {
        gl_state.elementbufferobject = bufferobject;
        CHECKGLERROR
        qglBindBuffer(GL_ELEMENT_ARRAY_BUFFER, bufferobject);CHECKGLERROR
    }
}
 
static void GL_BindUBO(int bufferobject)
{
    if (gl_state.uniformbufferobject != bufferobject)
    {
        gl_state.uniformbufferobject = bufferobject;
#ifdef GL_UNIFORM_BUFFER
        CHECKGLERROR
        qglBindBuffer(GL_UNIFORM_BUFFER, bufferobject);CHECKGLERROR
#endif
    }
}
 
static const GLuint drawbuffers[4] = {GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1, GL_COLOR_ATTACHMENT2, GL_COLOR_ATTACHMENT3};
int R_Mesh_CreateFramebufferObject(rtexture_t *depthtexture, rtexture_t *colortexture, rtexture_t *colortexture2, rtexture_t *colortexture3, rtexture_t *colortexture4)
{
    int temp;
    GLuint status;
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
        qglGenFramebuffers(1, (GLuint*)&temp);CHECKGLERROR
 
#ifndef USE_GLES2
        R_Mesh_SetRenderTargets(temp);  // This breaks GLES2.
        // GL_ARB_framebuffer_object (GL3-class hardware) - depth stencil attachment
#endif
 
#ifdef USE_GLES2
        // FIXME: separate stencil attachment on GLES
        if (depthtexture  && depthtexture->texnum ) { qglFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT  , depthtexture->gltexturetypeenum , depthtexture->texnum , 0);CHECKGLERROR }
        if (depthtexture  && depthtexture->renderbuffernum ) { qglFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT  , GL_RENDERBUFFER, depthtexture->renderbuffernum );CHECKGLERROR }
#else
        if (depthtexture  && depthtexture->texnum )
        {
            qglFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT  , depthtexture->gltexturetypeenum , depthtexture->texnum , 0);CHECKGLERROR
            if (depthtexture->glisdepthstencil) { qglFramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT  , depthtexture->gltexturetypeenum , depthtexture->texnum , 0);CHECKGLERROR }
        }
        if (depthtexture  && depthtexture->renderbuffernum )
        {
            qglFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT  , GL_RENDERBUFFER, depthtexture->renderbuffernum );CHECKGLERROR
            if (depthtexture->glisdepthstencil) { qglFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT  , GL_RENDERBUFFER, depthtexture->renderbuffernum );CHECKGLERROR }
        }
#endif
 
        if (colortexture  && colortexture->texnum ) { qglFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 , colortexture->gltexturetypeenum , colortexture->texnum , 0);CHECKGLERROR }
        if (colortexture2 && colortexture2->texnum) { qglFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1 , colortexture2->gltexturetypeenum, colortexture2->texnum, 0);CHECKGLERROR }
        if (colortexture3 && colortexture3->texnum) { qglFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT2 , colortexture3->gltexturetypeenum, colortexture3->texnum, 0);CHECKGLERROR }
        if (colortexture4 && colortexture4->texnum) { qglFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT3 , colortexture4->gltexturetypeenum, colortexture4->texnum, 0);CHECKGLERROR }
        if (colortexture  && colortexture->renderbuffernum ) { qglFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 , GL_RENDERBUFFER, colortexture->renderbuffernum );CHECKGLERROR }
        if (colortexture2 && colortexture2->renderbuffernum) { qglFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1 , GL_RENDERBUFFER, colortexture2->renderbuffernum);CHECKGLERROR }
        if (colortexture3 && colortexture3->renderbuffernum) { qglFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT2 , GL_RENDERBUFFER, colortexture3->renderbuffernum);CHECKGLERROR }
        if (colortexture4 && colortexture4->renderbuffernum) { qglFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT3 , GL_RENDERBUFFER, colortexture4->renderbuffernum);CHECKGLERROR }
 
#ifndef USE_GLES2
        if (colortexture4)
        {
            qglDrawBuffers(4, drawbuffers);CHECKGLERROR
            qglReadBuffer(GL_NONE);CHECKGLERROR
        }
        else if (colortexture3)
        {
            qglDrawBuffers(3, drawbuffers);CHECKGLERROR
            qglReadBuffer(GL_NONE);CHECKGLERROR
        }
        else if (colortexture2)
        {
            qglDrawBuffers(2, drawbuffers);CHECKGLERROR
            qglReadBuffer(GL_NONE);CHECKGLERROR
        }
        else if (colortexture)
        {
            qglDrawBuffer(GL_COLOR_ATTACHMENT0);CHECKGLERROR
            qglReadBuffer(GL_COLOR_ATTACHMENT0);CHECKGLERROR
        }
        else
        {
            qglDrawBuffer(GL_NONE);CHECKGLERROR
            qglReadBuffer(GL_NONE);CHECKGLERROR
        }
#endif
        status = qglCheckFramebufferStatus(GL_FRAMEBUFFER);CHECKGLERROR
        if (status != GL_FRAMEBUFFER_COMPLETE)
        {
            Con_Printf(CON_ERROR "R_Mesh_CreateFramebufferObject: glCheckFramebufferStatus returned %i\n", status);
            gl_state.framebufferobject = 0; // GL unbinds it for us
            qglDeleteFramebuffers(1, (GLuint*)&temp);CHECKGLERROR
            temp = 0;
        }
        return temp;
    }
    return 0;
}
 
void R_Mesh_DestroyFramebufferObject(int fbo)
{
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        if (fbo)
        {
            // GL clears the binding if we delete something bound
            if (gl_state.framebufferobject == fbo)
                gl_state.framebufferobject = 0;
            qglDeleteFramebuffers(1, (GLuint*)&fbo);CHECKGLERROR
        }
        break;
    }
}
 
void R_Mesh_SetRenderTargets(int fbo)
{
    // set up framebuffer object or render targets for the active rendering API
    switch (vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        if (gl_state.framebufferobject != fbo)
        {
            gl_state.framebufferobject = fbo;
            qglBindFramebuffer(GL_FRAMEBUFFER, gl_state.framebufferobject ? gl_state.framebufferobject : gl_state.defaultframebufferobject);CHECKGLERROR
        }
        break;
    }
}
 
static void GL_Backend_ResetState(void)
{
    gl_state.active = true;
    gl_state.depthtest = true;
    gl_state.alphatocoverage = false;
    gl_state.blendfunc1 = GL_ONE;
    gl_state.blendfunc2 = GL_ZERO;
    gl_state.blend = false;
    gl_state.depthmask = GL_TRUE;
    gl_state.colormask = 15;
    gl_state.color4f[0] = gl_state.color4f[1] = gl_state.color4f[2] = gl_state.color4f[3] = 1;
    gl_state.lockrange_first = 0;
    gl_state.lockrange_count = 0;
    gl_state.cullface = GL_FRONT;
    gl_state.cullfaceenable = false;
    gl_state.polygonoffset[0] = 0;
    gl_state.polygonoffset[1] = 0;
    gl_state.framebufferobject = 0;
    gl_state.depthfunc = GL_LEQUAL;
 
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        // set up debug output early
        if (gl_debug.integer > 0 && vid.support.arb_debug_output)
        {
            GLuint unused = 0;
            CHECKGLERROR
            Con_Print("gl_debug: GL_ARB_debug_output is supported, enabling callback\n");
            if (gl_debug.integer >= 1)
                qglEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS_ARB);
            if (gl_debug.integer >= 3)
                qglDebugMessageControlARB(GL_DONT_CARE, GL_DONT_CARE, GL_DONT_CARE, 0, &unused, gl_debug.integer >= 3 ? GL_TRUE : GL_FALSE);
            else if (gl_debug.integer >= 1)
            {
                qglDebugMessageControlARB(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_LOW_ARB, 0, &unused, gl_debug.integer >= 3 ? GL_TRUE : GL_FALSE);
                qglDebugMessageControlARB(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_MEDIUM_ARB, 0, &unused, gl_debug.integer >= 2 ? GL_TRUE : GL_FALSE);
                qglDebugMessageControlARB(GL_DONT_CARE, GL_DONT_CARE, GL_DEBUG_SEVERITY_HIGH_ARB, 0, &unused, gl_debug.integer >= 1 ? GL_TRUE : GL_FALSE);
            }
            else
                qglDebugMessageControlARB(GL_DONT_CARE, GL_DONT_CARE, GL_DONT_CARE, 0, &unused, GL_FALSE);
            qglDebugMessageCallbackARB(GL_DebugOutputCallback, NULL);
        }
        CHECKGLERROR
        qglColorMask(1, 1, 1, 1);CHECKGLERROR
        qglBlendFunc(gl_state.blendfunc1, gl_state.blendfunc2);CHECKGLERROR
        qglDisable(GL_BLEND);CHECKGLERROR
        qglCullFace(gl_state.cullface);CHECKGLERROR
        qglDisable(GL_CULL_FACE);CHECKGLERROR
        qglDepthFunc(GL_LEQUAL);CHECKGLERROR
        qglEnable(GL_DEPTH_TEST);CHECKGLERROR
        qglDepthMask(gl_state.depthmask);CHECKGLERROR
        qglPolygonOffset(gl_state.polygonoffset[0], gl_state.polygonoffset[1]);
        qglBindBuffer(GL_ARRAY_BUFFER, 0);
        qglBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
        qglBindFramebuffer(GL_FRAMEBUFFER, gl_state.defaultframebufferobject);
        qglEnableVertexAttribArray(GLSLATTRIB_POSITION);
        qglDisableVertexAttribArray(GLSLATTRIB_COLOR);
        qglVertexAttrib4f(GLSLATTRIB_COLOR, 1, 1, 1, 1);
        gl_state.unit = MAX_TEXTUREUNITS;
        CHECKGLERROR
        break;
    }
}
 
void GL_ActiveTexture(unsigned int num)
{
    if (gl_state.unit != num)
    {
        gl_state.unit = num;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            qglActiveTexture(GL_TEXTURE0 + gl_state.unit);CHECKGLERROR
            break;
        }
    }
}
 
void GL_BlendFunc(int blendfunc1, int blendfunc2)
{
    if (gl_state.blendfunc1 != blendfunc1 || gl_state.blendfunc2 != blendfunc2)
    {
        qbool blendenable;
        gl_state.blendfunc1 = blendfunc1;
        gl_state.blendfunc2 = blendfunc2;
        blendenable = (gl_state.blendfunc1 != GL_ONE || gl_state.blendfunc2 != GL_ZERO);
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            if (qglBlendFuncSeparate)
            {
                qglBlendFuncSeparate(gl_state.blendfunc1, gl_state.blendfunc2, GL_ZERO, GL_ONE);CHECKGLERROR // ELUAN: Adreno 225 (and others) compositing workaround
            }
            else
            {
                qglBlendFunc(gl_state.blendfunc1, gl_state.blendfunc2);CHECKGLERROR
            }
            if (gl_state.blend != blendenable)
            {
                gl_state.blend = blendenable;
                if (!gl_state.blend)
                {
                    qglDisable(GL_BLEND);CHECKGLERROR
                }
                else
                {
                    qglEnable(GL_BLEND);CHECKGLERROR
                }
            }
            break;
        }
    }
}
 
void GL_DepthMask(int state)
{
    if (gl_state.depthmask != state)
    {
        gl_state.depthmask = state;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            qglDepthMask(gl_state.depthmask);CHECKGLERROR
            break;
        }
    }
}
 
void GL_DepthTest(int state)
{
    if (gl_state.depthtest != state)
    {
        gl_state.depthtest = state;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            if (gl_state.depthtest)
            {
                qglEnable(GL_DEPTH_TEST);CHECKGLERROR
            }
            else
            {
                qglDisable(GL_DEPTH_TEST);CHECKGLERROR
            }
            break;
        }
    }
}
 
void GL_DepthFunc(int state)
{
    if (gl_state.depthfunc != state)
    {
        gl_state.depthfunc = state;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            qglDepthFunc(gl_state.depthfunc);CHECKGLERROR
            break;
        }
    }
}
 
void GL_DepthRange(float nearfrac, float farfrac)
{
    if (gl_state.depthrange[0] != nearfrac || gl_state.depthrange[1] != farfrac)
    {
        gl_state.depthrange[0] = nearfrac;
        gl_state.depthrange[1] = farfrac;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
#ifdef USE_GLES2
            qglDepthRangef(gl_state.depthrange[0], gl_state.depthrange[1]);CHECKGLERROR
#else
            qglDepthRange(gl_state.depthrange[0], gl_state.depthrange[1]);CHECKGLERROR
#endif
            break;
        }
    }
}
 
void R_SetStencil(qbool enable, int writemask, int fail, int zfail, int zpass, int compare, int comparereference, int comparemask)
{
    switch (vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
        if (enable)
        {
            qglEnable(GL_STENCIL_TEST);CHECKGLERROR
        }
        else
        {
            qglDisable(GL_STENCIL_TEST);CHECKGLERROR
        }
        qglStencilMask(writemask);CHECKGLERROR
        qglStencilOp(fail, zfail, zpass);CHECKGLERROR
        qglStencilFunc(compare, comparereference, comparemask);CHECKGLERROR
        CHECKGLERROR
        break;
    }
}
 
void GL_PolygonOffset(float planeoffset, float depthoffset)
{
    if (gl_state.polygonoffset[0] != planeoffset || gl_state.polygonoffset[1] != depthoffset)
    {
        gl_state.polygonoffset[0] = planeoffset;
        gl_state.polygonoffset[1] = depthoffset;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            qglPolygonOffset(gl_state.polygonoffset[0], gl_state.polygonoffset[1]);CHECKGLERROR
            break;
        }
    }
}
 
void GL_SetMirrorState(qbool state)
{
    if (v_flipped_state != state)
    {
        v_flipped_state = state;
        if (gl_state.cullface == GL_BACK)
            gl_state.cullface = GL_FRONT;
        else if (gl_state.cullface == GL_FRONT)
            gl_state.cullface = GL_BACK;
        else
            return;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            qglCullFace(gl_state.cullface);CHECKGLERROR
            break;
        }
    }
}
 
void GL_CullFace(int state)
{
    if(v_flipped_state)
    {
        if(state == GL_FRONT)
            state = GL_BACK;
        else if(state == GL_BACK)
            state = GL_FRONT;
    }
 
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
 
        if (state != GL_NONE)
        {
            if (!gl_state.cullfaceenable)
            {
                gl_state.cullfaceenable = true;
                qglEnable(GL_CULL_FACE);CHECKGLERROR
            }
            if (gl_state.cullface != state)
            {
                gl_state.cullface = state;
                qglCullFace(gl_state.cullface);CHECKGLERROR
            }
        }
        else
        {
            if (gl_state.cullfaceenable)
            {
                gl_state.cullfaceenable = false;
                qglDisable(GL_CULL_FACE);CHECKGLERROR
            }
        }
        break;
    }
}
 
void GL_AlphaToCoverage(qbool state)
{
    if (gl_state.alphatocoverage != state)
    {
        gl_state.alphatocoverage = state;
        switch(vid.renderpath)
        {
        case RENDERPATH_GLES2:
            break;
        case RENDERPATH_GL32:
#ifndef USE_GLES2
            // alpha to coverage turns the alpha value of the pixel into 0%, 25%, 50%, 75% or 100% by masking the multisample fragments accordingly
            CHECKGLERROR
            if (gl_state.alphatocoverage)
            {
                qglEnable(GL_SAMPLE_ALPHA_TO_COVERAGE);CHECKGLERROR
//              qglEnable(GL_MULTISAMPLE);CHECKGLERROR
            }
            else
            {
                qglDisable(GL_SAMPLE_ALPHA_TO_COVERAGE);CHECKGLERROR
//              qglDisable(GL_MULTISAMPLE);CHECKGLERROR
            }
#endif
            break;
        }
    }
}
 
void GL_ColorMask(int r, int g, int b, int a)
{
    // NOTE: this matches D3DCOLORWRITEENABLE_RED, GREEN, BLUE, ALPHA
    int state = (r ? 1 : 0) | (g ? 2 : 0) | (b ? 4 : 0) | (a ? 8 : 0);
    if (gl_state.colormask != state)
    {
        gl_state.colormask = state;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            qglColorMask((GLboolean)r, (GLboolean)g, (GLboolean)b, (GLboolean)a);CHECKGLERROR
            break;
        }
    }
}
 
void GL_Color(float cr, float cg, float cb, float ca)
{
    if (gl_state.pointer_color_enabled || gl_state.color4f[0] != cr || gl_state.color4f[1] != cg || gl_state.color4f[2] != cb || gl_state.color4f[3] != ca)
    {
        gl_state.color4f[0] = cr;
        gl_state.color4f[1] = cg;
        gl_state.color4f[2] = cb;
        gl_state.color4f[3] = ca;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            qglVertexAttrib4f(GLSLATTRIB_COLOR, cr, cg, cb, ca);CHECKGLERROR
            break;
        }
    }
}
 
void GL_Scissor (int x, int y, int width, int height)
{
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
        qglScissor(x, y,width,height);CHECKGLERROR
        break;
    }
}
 
void GL_ScissorTest(int state)
{
    if (gl_state.scissortest != state)
    {
        gl_state.scissortest = state;
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            if(gl_state.scissortest)
                qglEnable(GL_SCISSOR_TEST);
            else
                qglDisable(GL_SCISSOR_TEST);
            CHECKGLERROR
            break;
        }
    }
}
 
void GL_Clear(int mask, const float *colorvalue, float depthvalue, int stencilvalue)
{
    // opaque black - if you want transparent black, you'll need to pass in a colorvalue
    static const float blackcolor[4] = {0.0f, 0.0f, 0.0f, 1.0f};
    // prevent warnings when trying to clear a buffer that does not exist
    if (!colorvalue)
        colorvalue = blackcolor;
    if (!vid.stencil)
    {
        mask &= ~GL_STENCIL_BUFFER_BIT;
        stencilvalue = 0;
    }
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
        if (mask & GL_COLOR_BUFFER_BIT)
        {
            qglClearColor(colorvalue[0], colorvalue[1], colorvalue[2], colorvalue[3]);CHECKGLERROR
        }
        if (mask & GL_DEPTH_BUFFER_BIT)
        {
#ifdef USE_GLES2
            //qglClearDepthf(depthvalue);CHECKGLERROR
#else
            qglClearDepth(depthvalue);CHECKGLERROR
#endif
        }
        if (mask & GL_STENCIL_BUFFER_BIT)
        {
            qglClearStencil(stencilvalue);CHECKGLERROR
        }
        qglClear(mask);CHECKGLERROR
        break;
    }
}
 
void GL_ReadPixelsBGRA(int x, int y, int width, int height, unsigned char *outpixels)
{
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
        CHECKGLERROR
        qglReadPixels(x, y, width, height, GL_BGRA, GL_UNSIGNED_BYTE, outpixels);CHECKGLERROR
        break;
    case RENDERPATH_GLES2: // glReadPixels() lacks GL_BGRA support (even in ES 3.2)
        CHECKGLERROR
        {
            int i;
            int r;
        //  int g;
            int b;
        //  int a;
            qglReadPixels(x, y, width, height, GL_RGBA, GL_UNSIGNED_BYTE, outpixels);CHECKGLERROR
            for (i = 0;i < width * height * 4;i += 4)
            {
                r = outpixels[i+0];
        //      g = outpixels[i+1];
                b = outpixels[i+2];
        //      a = outpixels[i+3];
                outpixels[i+0] = b;
        //      outpixels[i+1] = g;
                outpixels[i+2] = r;
        //      outpixels[i+3] = a;
            }
        }
        break;
    }
}
 
 
#ifdef CONFIG_VIDEO_CAPTURE
/*
 * GL_CaptureVideo*
 * GPU scaling and async DMA transfer of completed frames
 * Minimum GL version: 3.0, for glBlitFramebuffer
 * Minimum GLES version: 3.0, for glBlitFramebuffer and GL_PIXEL_PACK_BUFFER (PBOs)
 */
 
void GL_CaptureVideo_BeginVideo(void)
{
    int width = cls.capturevideo.width, height = cls.capturevideo.height;
    // format is GL_BGRA type is GL_UNSIGNED_BYTE
    GLsizeiptr data_size = width * height * 4;
 
// create PBOs
    qglGenBuffers(PBO_COUNT, cls.capturevideo.PBOs);
    for (int i = 0; i < PBO_COUNT; ++i)
    {
        qglBindBuffer(GL_PIXEL_PACK_BUFFER, cls.capturevideo.PBOs[i]);
        // Allocate memory and leave it uninitialised.
        qglBufferData(GL_PIXEL_PACK_BUFFER, data_size, NULL, GL_DYNAMIC_READ);CHECKGLERROR
    }
    qglBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
 
// If scaling is necessary create an FBO with attached texture
    if (width == vid.mode.width && height == vid.mode.height)
    {
        cls.capturevideo.FBO = 0;
        return;
    }
    qglGenFramebuffers(1, &cls.capturevideo.FBO);
    qglBindFramebuffer(GL_FRAMEBUFFER, cls.capturevideo.FBO);
    qglGenTextures(1, &cls.capturevideo.FBOtex);
    qglBindTexture(GL_TEXTURE_2D, cls.capturevideo.FBOtex);
    // Allocate memory and leave it uninitialised (format and type don't matter: data is NULL).
    // Same internalformat as TEXTYPE_COLORBUFFER.
    qglTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);CHECKGLERROR
    qglFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, cls.capturevideo.FBOtex, 0);CHECKGLERROR
    qglBindTexture(GL_TEXTURE_2D, 0);
    qglBindFramebuffer(GL_FRAMEBUFFER, 0);
}
 
void GL_CaptureVideo_VideoFrame(int newframestepframenum)
{
    int width = cls.capturevideo.width, height = cls.capturevideo.height;
    GLubyte *pixbuf;
    GLuint oldestPBOindex;
 
    if (++cls.capturevideo.PBOindex >= PBO_COUNT)
        cls.capturevideo.PBOindex = 0;
    if ((oldestPBOindex = cls.capturevideo.PBOindex + 1) >= PBO_COUNT)
        oldestPBOindex = 0;
 
    // Ensure we'll read from the default FB
    R_Mesh_SetRenderTargets(0);
 
    // If necessary, scale the newest frame with linear filtering
    if (cls.capturevideo.FBO)
    {
        qglBindFramebuffer(GL_DRAW_FRAMEBUFFER, cls.capturevideo.FBO);
        qglBlitFramebuffer(0, 0, vid.mode.width, vid.mode.height, 0, 0, width, height, GL_COLOR_BUFFER_BIT, GL_LINEAR);CHECKGLERROR
        qglBindFramebuffer(GL_READ_FRAMEBUFFER, cls.capturevideo.FBO);
    }
 
    // Copy the newest frame to a PBO for later CPU access.
    qglBindBuffer(GL_PIXEL_PACK_BUFFER, cls.capturevideo.PBOs[cls.capturevideo.PBOindex]);
    qglReadPixels(0, 0, width, height, GL_BGRA, GL_UNSIGNED_BYTE, 0);CHECKGLERROR
 
    if (cls.capturevideo.FBO)
        qglBindFramebuffer(GL_FRAMEBUFFER, 0);
 
    // Save the oldest frame from its PBO (blocks until sync if still not ready)
    // speed is critical here, so do saving as directly as possible
    if (newframestepframenum >= PBO_COUNT) // Don't read uninitialised memory, newframestepframenum starts at 1
    {
        qglBindBuffer(GL_PIXEL_PACK_BUFFER, cls.capturevideo.PBOs[oldestPBOindex]);
        pixbuf = (GLubyte *)qglMapBuffer(GL_PIXEL_PACK_BUFFER, GL_READ_ONLY);CHECKGLERROR
        if(pixbuf)
        {
            cls.capturevideo.writeVideoFrame(newframestepframenum - cls.capturevideo.framestepframe, pixbuf);
            qglUnmapBuffer(GL_PIXEL_PACK_BUFFER);
        }
    }
 
    qglBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
}
 
void GL_CaptureVideo_EndVideo(void)
{
    // SCR_CaptureVideo won't call GL_CaptureVideo_VideoFrame again
    // but the last frame(s) are waiting in PBO(s) due to async transfer.
    // On the last normal frame we queued to 1 PBO and saved from 1, so we have PBO_COUNT-1 left
    for (int i = 1; i < PBO_COUNT; ++i)
        GL_CaptureVideo_VideoFrame(cls.capturevideo.framestepframe + i);
 
    qglDeleteTextures(1, &cls.capturevideo.FBOtex);
    qglDeleteFramebuffers(1, &cls.capturevideo.FBO);
    qglDeleteBuffers(PBO_COUNT, cls.capturevideo.PBOs);
}
#endif
 
 
// called at beginning of frame
void R_Mesh_Start(void)
{
    BACKENDACTIVECHECK
    R_Mesh_SetRenderTargets(0);
#ifdef DEBUGGL // gl_printcheckerror isn't registered in normal builds
    if (gl_printcheckerror.integer && !gl_paranoid.integer)
    {
        Con_Printf(CON_WARN "WARNING: gl_printcheckerror is on but gl_paranoid is off, turning it on...\n");
        Cvar_SetValueQuick(&gl_paranoid, 1);
    }
#endif
}
 
static qbool GL_Backend_CompileShader(int programobject, GLenum shadertypeenum, const char *shadertype, int numstrings, const char **strings)
{
    int shaderobject;
    int shadercompiled;
    char compilelog[MAX_INPUTLINE];
    shaderobject = qglCreateShader(shadertypeenum);CHECKGLERROR
    if (!shaderobject)
        return false;
    qglShaderSource(shaderobject, numstrings, strings, NULL);CHECKGLERROR
    qglCompileShader(shaderobject);CHECKGLERROR
    qglGetShaderiv(shaderobject, GL_COMPILE_STATUS, &shadercompiled);CHECKGLERROR
    qglGetShaderInfoLog(shaderobject, sizeof(compilelog), NULL, compilelog);CHECKGLERROR
    if (compilelog[0] && ((strstr(compilelog, "error") || strstr(compilelog, "ERROR") || strstr(compilelog, "Error")) || ((strstr(compilelog, "WARNING") || strstr(compilelog, "warning") || strstr(compilelog, "Warning")) && developer.integer) || developer_extra.integer))
    {
        int i, j, pretextlines = 0;
        for (i = 0;i < numstrings - 1;i++)
            for (j = 0;strings[i][j];j++)
                if (strings[i][j] == '\n')
                    pretextlines++;
        Con_Printf("%s shader compile log:\n%s\n(line offset for any above warnings/errors: %i)\n", shadertype, compilelog, pretextlines);
    }
    if (!shadercompiled)
    {
        qglDeleteShader(shaderobject);CHECKGLERROR
        return false;
    }
    qglAttachShader(programobject, shaderobject);CHECKGLERROR
    qglDeleteShader(shaderobject);CHECKGLERROR
    return true;
}
 
unsigned int GL_Backend_CompileProgram(int vertexstrings_count, const char **vertexstrings_list, int geometrystrings_count, const char **geometrystrings_list, int fragmentstrings_count, const char **fragmentstrings_list)
{
    GLint programlinked;
    GLuint programobject = 0;
    char linklog[MAX_INPUTLINE];
    CHECKGLERROR
 
    programobject = qglCreateProgram();CHECKGLERROR
    if (!programobject)
        return 0;
 
    qglBindAttribLocation(programobject, GLSLATTRIB_POSITION , "Attrib_Position" );
    qglBindAttribLocation(programobject, GLSLATTRIB_COLOR    , "Attrib_Color"    );
    qglBindAttribLocation(programobject, GLSLATTRIB_TEXCOORD0, "Attrib_TexCoord0");
    qglBindAttribLocation(programobject, GLSLATTRIB_TEXCOORD1, "Attrib_TexCoord1");
    qglBindAttribLocation(programobject, GLSLATTRIB_TEXCOORD2, "Attrib_TexCoord2");
    qglBindAttribLocation(programobject, GLSLATTRIB_TEXCOORD3, "Attrib_TexCoord3");
    qglBindAttribLocation(programobject, GLSLATTRIB_TEXCOORD4, "Attrib_TexCoord4");
    qglBindAttribLocation(programobject, GLSLATTRIB_TEXCOORD5, "Attrib_TexCoord5");
    qglBindAttribLocation(programobject, GLSLATTRIB_TEXCOORD6, "Attrib_SkeletalIndex");
    qglBindAttribLocation(programobject, GLSLATTRIB_TEXCOORD7, "Attrib_SkeletalWeight");
#ifndef USE_GLES2
    qglBindFragDataLocation(programobject, 0, "dp_FragColor");
#endif
    CHECKGLERROR
 
    if (vertexstrings_count && !GL_Backend_CompileShader(programobject, GL_VERTEX_SHADER, "vertex", vertexstrings_count, vertexstrings_list))
        goto cleanup;
 
#if defined(GL_GEOMETRY_SHADER) && !defined(USE_GLES2)
    if (geometrystrings_count && !GL_Backend_CompileShader(programobject, GL_GEOMETRY_SHADER, "geometry", geometrystrings_count, geometrystrings_list))
        goto cleanup;
#endif
 
    if (fragmentstrings_count && !GL_Backend_CompileShader(programobject, GL_FRAGMENT_SHADER, "fragment", fragmentstrings_count, fragmentstrings_list))
        goto cleanup;
 
    qglLinkProgram(programobject);CHECKGLERROR
    qglGetProgramiv(programobject, GL_LINK_STATUS, &programlinked);CHECKGLERROR
    qglGetProgramInfoLog(programobject, sizeof(linklog), NULL, linklog);CHECKGLERROR
 
    if (linklog[0])
    {
 
        if (strstr(linklog, "error") || strstr(linklog, "ERROR") || strstr(linklog, "Error") || strstr(linklog, "WARNING") || strstr(linklog, "warning") || strstr(linklog, "Warning") || developer_extra.integer)
            Con_DPrintf("program link log:\n%s\n", linklog);
 
        // software vertex shader is ok but software fragment shader is WAY
        // too slow, fail program if so.
        // NOTE: this string might be ATI specific, but that's ok because the
        // ATI R300 chip (Radeon 9500-9800/X300) is the most likely to use a
        // software fragment shader due to low instruction and dependent
        // texture limits.
        if (strstr(linklog, "fragment shader will run in software"))
            programlinked = false;
    }
 
    if (!programlinked)
        goto cleanup;
 
    return programobject;
cleanup:
    qglDeleteProgram(programobject);CHECKGLERROR
    return 0;
}
 
void GL_Backend_FreeProgram(unsigned int prog)
{
    CHECKGLERROR
    qglDeleteProgram(prog);
    CHECKGLERROR
}
 
// renders triangles using vertices from the active arrays
void R_Mesh_Draw(int firstvertex, int numvertices, int firsttriangle, int numtriangles, const int *element3i, const r_meshbuffer_t *element3i_indexbuffer, int element3i_bufferoffset, const unsigned short *element3s, const r_meshbuffer_t *element3s_indexbuffer, int element3s_bufferoffset)
{
    unsigned int numelements = numtriangles * 3;
    int bufferobject3i;
    size_t bufferoffset3i;
    int bufferobject3s;
    size_t bufferoffset3s;
    if (numvertices < 3 || numtriangles < 1)
    {
        if (numvertices < 0 || numtriangles < 0 || developer_extra.integer)
            Con_DPrintf("R_Mesh_Draw(%d, %d, %d, %d, %8p, %8p, %8x, %8p, %8p, %8x);\n", firstvertex, numvertices, firsttriangle, numtriangles, (void *)element3i, (void *)element3i_indexbuffer, (int)element3i_bufferoffset, (void *)element3s, (void *)element3s_indexbuffer, (int)element3s_bufferoffset);
        return;
    }
    // adjust the pointers for firsttriangle
    if (element3i)
        element3i += firsttriangle * 3;
    if (element3i_indexbuffer)
        element3i_bufferoffset += firsttriangle * 3 * sizeof(*element3i);
    if (element3s)
        element3s += firsttriangle * 3;
    if (element3s_indexbuffer)
        element3s_bufferoffset += firsttriangle * 3 * sizeof(*element3s);
    // upload a dynamic index buffer if needed
    if (element3s)
    {
        if (!element3s_indexbuffer)
            element3s_indexbuffer = R_BufferData_Store(numelements * sizeof(*element3s), (void *)element3s, R_BUFFERDATA_INDEX16, &element3s_bufferoffset);
    }
    else if (element3i)
    {
        if (!element3i_indexbuffer)
            element3i_indexbuffer = R_BufferData_Store(numelements * sizeof(*element3i), (void *)element3i, R_BUFFERDATA_INDEX32, &element3i_bufferoffset);
    }
    bufferobject3i = element3i_indexbuffer ? element3i_indexbuffer->bufferobject : 0;
    bufferoffset3i = element3i_bufferoffset;
    bufferobject3s = element3s_indexbuffer ? element3s_indexbuffer->bufferobject : 0;
    bufferoffset3s = element3s_bufferoffset;
    r_refdef.stats[r_stat_draws]++;
    r_refdef.stats[r_stat_draws_vertices] += numvertices;
    r_refdef.stats[r_stat_draws_elements] += numelements;
    if (gl_paranoid.integer)
    {
        unsigned int i;
        if (element3i)
        {
            for (i = 0;i < (unsigned int) numtriangles * 3;i++)
            {
                if (element3i[i] < firstvertex || element3i[i] >= firstvertex + numvertices)
                {
                    Con_Printf(CON_WARN "R_Mesh_Draw: invalid vertex index %i (outside range %i - %i) in element3i array\n", element3i[i], firstvertex, firstvertex + numvertices);
                    return;
                }
            }
        }
        if (element3s)
        {
            for (i = 0;i < (unsigned int) numtriangles * 3;i++)
            {
                if (element3s[i] < firstvertex || element3s[i] >= firstvertex + numvertices)
                {
                    Con_Printf(CON_WARN "R_Mesh_Draw: invalid vertex index %i (outside range %i - %i) in element3s array\n", element3s[i], firstvertex, firstvertex + numvertices);
                    return;
                }
            }
        }
    }
    if (r_render.integer || r_refdef.draw2dstage)
    {
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            CHECKGLERROR
            if (bufferobject3s)
            {
                GL_BindEBO(bufferobject3s);
                qglDrawElements(GL_TRIANGLES, numelements, GL_UNSIGNED_SHORT, (void *)bufferoffset3s);CHECKGLERROR
            }
            else if (bufferobject3i)
            {
                GL_BindEBO(bufferobject3i);
                qglDrawElements(GL_TRIANGLES, numelements, GL_UNSIGNED_INT, (void *)bufferoffset3i);CHECKGLERROR
            }
            else
            {
                qglDrawArrays(GL_TRIANGLES, firstvertex, numvertices);CHECKGLERROR
            }
            break;
        }
    }
}
 
// restores backend state, used when done with 3D rendering
void R_Mesh_Finish(void)
{
    R_Mesh_SetRenderTargets(0);
}
 
r_meshbuffer_t *R_Mesh_CreateMeshBuffer(const void *data, size_t size, const char *name, qbool isindexbuffer, qbool isuniformbuffer, qbool isdynamic, qbool isindex16)
{
    r_meshbuffer_t *buffer;
    buffer = (r_meshbuffer_t *)Mem_ExpandableArray_AllocRecord(&gl_state.meshbufferarray);
    memset(buffer, 0, sizeof(*buffer));
    buffer->bufferobject = 0;
    buffer->devicebuffer = NULL;
    buffer->size = size;
    buffer->isindexbuffer = isindexbuffer;
    buffer->isuniformbuffer = isuniformbuffer;
    buffer->isdynamic = isdynamic;
    buffer->isindex16 = isindex16;
    dp_strlcpy(buffer->name, name, sizeof(buffer->name));
    R_Mesh_UpdateMeshBuffer(buffer, data, size, false, 0);
    return buffer;
}
 
void R_Mesh_UpdateMeshBuffer(r_meshbuffer_t *buffer, const void *data, size_t size, qbool subdata, size_t offset)
{
    if (!buffer)
        return;
    if (buffer->isindexbuffer)
    {
        r_refdef.stats[r_stat_indexbufferuploadcount]++;
        r_refdef.stats[r_stat_indexbufferuploadsize] += (int)size;
    }
    else
    {
        r_refdef.stats[r_stat_vertexbufferuploadcount]++;
        r_refdef.stats[r_stat_vertexbufferuploadsize] += (int)size;
    }
    if (!subdata)
        buffer->size = size;
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        if (!buffer->bufferobject)
            qglGenBuffers(1, (GLuint *)&buffer->bufferobject);
        CHECKGLERROR
        if (buffer->isuniformbuffer)
            GL_BindUBO(buffer->bufferobject);
        else if (buffer->isindexbuffer)
            GL_BindEBO(buffer->bufferobject);
        else
            GL_BindVBO(buffer->bufferobject);
 
        {
            int buffertype;
            buffertype = buffer->isindexbuffer ? GL_ELEMENT_ARRAY_BUFFER : GL_ARRAY_BUFFER;
#ifdef GL_UNIFORM_BUFFER
            if (buffer->isuniformbuffer)
                buffertype = GL_UNIFORM_BUFFER;
#endif
            CHECKGLERROR
            if (subdata)
                qglBufferSubData(buffertype, offset, size, data);
            else
                qglBufferData(buffertype, size, data, buffer->isdynamic ? GL_STREAM_DRAW : GL_STATIC_DRAW);
            CHECKGLERROR
        }
        if (buffer->isuniformbuffer)
            GL_BindUBO(0);
        break;
    }
}
 
void R_Mesh_DestroyMeshBuffer(r_meshbuffer_t *buffer)
{
    if (!buffer)
        return;
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        // GL clears the binding if we delete something bound
        if (gl_state.uniformbufferobject == buffer->bufferobject)
            gl_state.uniformbufferobject = 0;
        if (gl_state.vertexbufferobject == buffer->bufferobject)
            gl_state.vertexbufferobject = 0;
        if (gl_state.elementbufferobject == buffer->bufferobject)
            gl_state.elementbufferobject = 0;
        CHECKGLERROR
        qglDeleteBuffers(1, (GLuint *)&buffer->bufferobject);CHECKGLERROR
        break;
    }
    Mem_ExpandableArray_FreeRecord(&gl_state.meshbufferarray, (void *)buffer);
}
 
static const char *buffertypename[R_BUFFERDATA_COUNT] = {"vertex", "index16", "index32", "uniform"};
void GL_Mesh_ListVBOs(qbool printeach)
{
    int i, endindex;
    int type;
    int isdynamic;
    int index16count, index16mem;
    int index32count, index32mem;
    int vertexcount, vertexmem;
    int uniformcount, uniformmem;
    int totalcount, totalmem;
    size_t bufferstat[R_BUFFERDATA_COUNT][2][2];
    r_meshbuffer_t *buffer;
    memset(bufferstat, 0, sizeof(bufferstat));
    endindex = (int)Mem_ExpandableArray_IndexRange(&gl_state.meshbufferarray);
    for (i = 0;i < endindex;i++)
    {
        buffer = (r_meshbuffer_t *) Mem_ExpandableArray_RecordAtIndex(&gl_state.meshbufferarray, i);
        if (!buffer)
            continue;
        if (buffer->isuniformbuffer)
            type = R_BUFFERDATA_UNIFORM;
        else if (buffer->isindexbuffer && buffer->isindex16)
            type = R_BUFFERDATA_INDEX16;
        else if (buffer->isindexbuffer)
            type = R_BUFFERDATA_INDEX32;
        else
            type = R_BUFFERDATA_VERTEX;
        isdynamic = buffer->isdynamic;
        bufferstat[type][isdynamic][0]++;
        bufferstat[type][isdynamic][1] += buffer->size;
        if (printeach)
            Con_Printf("buffer #%i %s = %i bytes (%s %s)\n", i, buffer->name, (int)buffer->size, isdynamic ? "dynamic" : "static", buffertypename[type]);
    }
    index16count   = (int)(bufferstat[R_BUFFERDATA_INDEX16][0][0] + bufferstat[R_BUFFERDATA_INDEX16][1][0]);
    index16mem     = (int)(bufferstat[R_BUFFERDATA_INDEX16][0][1] + bufferstat[R_BUFFERDATA_INDEX16][1][1]);
    index32count   = (int)(bufferstat[R_BUFFERDATA_INDEX32][0][0] + bufferstat[R_BUFFERDATA_INDEX32][1][0]);
    index32mem     = (int)(bufferstat[R_BUFFERDATA_INDEX32][0][1] + bufferstat[R_BUFFERDATA_INDEX32][1][1]);
    vertexcount  = (int)(bufferstat[R_BUFFERDATA_VERTEX ][0][0] + bufferstat[R_BUFFERDATA_VERTEX ][1][0]);
    vertexmem    = (int)(bufferstat[R_BUFFERDATA_VERTEX ][0][1] + bufferstat[R_BUFFERDATA_VERTEX ][1][1]);
    uniformcount = (int)(bufferstat[R_BUFFERDATA_UNIFORM][0][0] + bufferstat[R_BUFFERDATA_UNIFORM][1][0]);
    uniformmem   = (int)(bufferstat[R_BUFFERDATA_UNIFORM][0][1] + bufferstat[R_BUFFERDATA_UNIFORM][1][1]);
    totalcount = index16count + index32count + vertexcount + uniformcount;
    totalmem = index16mem + index32mem + vertexmem + uniformmem;
    Con_Printf("%i 16bit indexbuffers totalling %i bytes (%.3f MB)\n%i 32bit indexbuffers totalling %i bytes (%.3f MB)\n%i vertexbuffers totalling %i bytes (%.3f MB)\n%i uniformbuffers totalling %i bytes (%.3f MB)\ncombined %i buffers totalling %i bytes (%.3fMB)\n", index16count, index16mem, index16mem / 10248576.0, index32count, index32mem, index32mem / 10248576.0, vertexcount, vertexmem, vertexmem / 10248576.0, uniformcount, uniformmem, uniformmem / 10248576.0, totalcount, totalmem, totalmem / 10248576.0);
}
 
 
 
void R_Mesh_VertexPointer(int components, int gltype, size_t stride, const void *pointer, const r_meshbuffer_t *vertexbuffer, size_t bufferoffset)
{
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        if (gl_state.pointer_vertex_components != components || gl_state.pointer_vertex_gltype != gltype || gl_state.pointer_vertex_stride != stride || gl_state.pointer_vertex_pointer != pointer || gl_state.pointer_vertex_vertexbuffer != vertexbuffer || gl_state.pointer_vertex_offset != bufferoffset)
        {
            int bufferobject = vertexbuffer ? vertexbuffer->bufferobject : 0;
            if (!bufferobject && gl_paranoid.integer)
                Con_DPrintf(CON_WARN "Warning: no bufferobject in R_Mesh_VertexPointer(%i, %i, %i, %p, %p, %08x)", components, gltype, (int)stride, pointer, (void *)vertexbuffer, (unsigned int)bufferoffset);
            gl_state.pointer_vertex_components = components;
            gl_state.pointer_vertex_gltype = gltype;
            gl_state.pointer_vertex_stride = stride;
            gl_state.pointer_vertex_pointer = pointer;
            gl_state.pointer_vertex_vertexbuffer = vertexbuffer;
            gl_state.pointer_vertex_offset = bufferoffset;
            CHECKGLERROR
            GL_BindVBO(bufferobject);
            // LadyHavoc: special flag added to gltype for unnormalized types
            qglVertexAttribPointer(GLSLATTRIB_POSITION, components, gltype & ~0x80000000, (gltype & 0x80000000) == 0, (GLsizei)stride, bufferobject ? (void *)bufferoffset : pointer);CHECKGLERROR
        }
        break;
    }
}
 
void R_Mesh_ColorPointer(int components, int gltype, size_t stride, const void *pointer, const r_meshbuffer_t *vertexbuffer, size_t bufferoffset)
{
    // note: vertexbuffer may be non-NULL even if pointer is NULL, so check
    // the pointer only.
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
        if (pointer)
        {
            // caller wants color array enabled
            int bufferobject = vertexbuffer ? vertexbuffer->bufferobject : 0;
            if (!gl_state.pointer_color_enabled)
            {
                gl_state.pointer_color_enabled = true;
                CHECKGLERROR
                qglEnableVertexAttribArray(GLSLATTRIB_COLOR);CHECKGLERROR
            }
            if (gl_state.pointer_color_components != components || gl_state.pointer_color_gltype != gltype || gl_state.pointer_color_stride != stride || gl_state.pointer_color_pointer != pointer || gl_state.pointer_color_vertexbuffer != vertexbuffer || gl_state.pointer_color_offset != bufferoffset)
            {
                gl_state.pointer_color_components = components;
                gl_state.pointer_color_gltype = gltype;
                gl_state.pointer_color_stride = stride;
                gl_state.pointer_color_pointer = pointer;
                gl_state.pointer_color_vertexbuffer = vertexbuffer;
                gl_state.pointer_color_offset = bufferoffset;
                CHECKGLERROR
                GL_BindVBO(bufferobject);
                // LadyHavoc: special flag added to gltype for unnormalized types
                qglVertexAttribPointer(GLSLATTRIB_COLOR, components, gltype & ~0x80000000, (gltype & 0x80000000) == 0, (GLsizei)stride, bufferobject ? (void *)bufferoffset : pointer);CHECKGLERROR
            }
        }
        else
        {
            // caller wants color array disabled
            if (gl_state.pointer_color_enabled)
            {
                gl_state.pointer_color_enabled = false;
                CHECKGLERROR
                qglDisableVertexAttribArray(GLSLATTRIB_COLOR);CHECKGLERROR
                // when color array is on the current color gets trashed, set it again
                qglVertexAttrib4f(GLSLATTRIB_COLOR, gl_state.color4f[0], gl_state.color4f[1], gl_state.color4f[2], gl_state.color4f[3]);CHECKGLERROR
            }
        }
        break;
    }
}
 
void R_Mesh_TexCoordPointer(unsigned int unitnum, int components, int gltype, size_t stride, const void *pointer, const r_meshbuffer_t *vertexbuffer, size_t bufferoffset)
{
    gltextureunit_t *unit = gl_state.units + unitnum;
    if (unitnum >= MAX_TEXTUREUNITS)
        Sys_Error("R_Mesh_TexCoordPointer: unitnum %i > max units %i\n", unitnum, MAX_TEXTUREUNITS);
    // update array settings
    // note: there is no need to check bufferobject here because all cases
    // that involve a valid bufferobject also supply a texcoord array
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        CHECKGLERROR
        if (pointer)
        {
            int bufferobject = vertexbuffer ? vertexbuffer->bufferobject : 0;
            // texture array unit is enabled, enable the array
            if (!unit->arrayenabled)
            {
                unit->arrayenabled = true;
                qglEnableVertexAttribArray(unitnum+GLSLATTRIB_TEXCOORD0);CHECKGLERROR
            }
            // texcoord array
            if (unit->pointer_texcoord_components != components || unit->pointer_texcoord_gltype != gltype || unit->pointer_texcoord_stride != stride || unit->pointer_texcoord_pointer != pointer || unit->pointer_texcoord_vertexbuffer != vertexbuffer || unit->pointer_texcoord_offset != bufferoffset)
            {
                unit->pointer_texcoord_components = components;
                unit->pointer_texcoord_gltype = gltype;
                unit->pointer_texcoord_stride = stride;
                unit->pointer_texcoord_pointer = pointer;
                unit->pointer_texcoord_vertexbuffer = vertexbuffer;
                unit->pointer_texcoord_offset = bufferoffset;
                GL_BindVBO(bufferobject);
                // LadyHavoc: special flag added to gltype for unnormalized types
                qglVertexAttribPointer(unitnum+GLSLATTRIB_TEXCOORD0, components, gltype & ~0x80000000, (gltype & 0x80000000) == 0, (GLsizei)stride, bufferobject ? (void *)bufferoffset : pointer);CHECKGLERROR
            }
        }
        else
        {
            // texture array unit is disabled, disable the array
            if (unit->arrayenabled)
            {
                unit->arrayenabled = false;
                qglDisableVertexAttribArray(unitnum+GLSLATTRIB_TEXCOORD0);CHECKGLERROR
            }
        }
        break;
    }
}
 
int R_Mesh_TexBound(unsigned int unitnum, int id)
{
    gltextureunit_t *unit = gl_state.units + unitnum;
    if (unitnum >= MAX_TEXTUREUNITS)
        Sys_Error("R_Mesh_TexCoordPointer: unitnum %i > max units %i\n", unitnum, MAX_TEXTUREUNITS);
    if (id == GL_TEXTURE_2D)
        return unit->t2d;
    if (id == GL_TEXTURE_3D)
        return unit->t3d;
    if (id == GL_TEXTURE_CUBE_MAP)
        return unit->tcubemap;
    return 0;
}
 
void R_Mesh_CopyToTexture(rtexture_t *tex, int tx, int ty, int sx, int sy, int width, int height)
{
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        R_Mesh_TexBind(0, tex);
        GL_ActiveTexture(0);CHECKGLERROR
        qglCopyTexSubImage2D(GL_TEXTURE_2D, 0, tx, ty, sx, sy, width, height);CHECKGLERROR
        break;
    }
}
 
void R_Mesh_ClearBindingsForTexture(int texnum)
{
    gltextureunit_t *unit;
    unsigned int unitnum;
    // unbind the texture from any units it is bound on - this prevents accidental reuse of certain textures whose bindings can linger far too long otherwise (e.g. bouncegrid which is a 3D texture) and confuse the driver later.
    for (unitnum = 0; unitnum < MAX_TEXTUREUNITS; unitnum++)
    {
        unit = gl_state.units + unitnum;
        if (unit->texture && unit->texture->texnum == texnum)
            R_Mesh_TexBind(unitnum, NULL);
    }
}
 
void R_Mesh_TexBind(unsigned int unitnum, rtexture_t *tex)
{
    gltextureunit_t *unit = gl_state.units + unitnum;
    int texnum;
    if (unitnum >= MAX_TEXTUREUNITS)
        Sys_Error("R_Mesh_TexBind: unitnum %i > max units %i\n", unitnum, MAX_TEXTUREUNITS);
    switch(vid.renderpath)
    {
    case RENDERPATH_GL32:
    case RENDERPATH_GLES2:
        if (tex)
        {
            texnum = R_GetTexture(tex);
            switch (tex->gltexturetypeenum)
            {
            case GL_TEXTURE_2D:
                if (unit->t2d != texnum) { GL_ActiveTexture(unitnum);qglBindTexture(GL_TEXTURE_2D, texnum); CHECKGLERROR unit->t2d = texnum; }
                if (unit->t3d) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_3D, 0); CHECKGLERROR unit->t3d = 0; }
                if (unit->tcubemap) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_CUBE_MAP, 0); CHECKGLERROR unit->tcubemap = 0; }
                break;
            case GL_TEXTURE_3D:
                if (unit->t2d) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_2D, 0); CHECKGLERROR unit->t2d = 0; }
                if (unit->t3d != texnum) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_3D, texnum); CHECKGLERROR unit->t3d = texnum; }
                if (unit->tcubemap) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_CUBE_MAP, 0); CHECKGLERROR unit->tcubemap = 0; }
                break;
            case GL_TEXTURE_CUBE_MAP:
                if (unit->t2d) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_2D, 0); CHECKGLERROR unit->t2d = 0; }
                if (unit->t3d) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_3D, 0); CHECKGLERROR unit->t3d = 0; }
                if (unit->tcubemap != texnum) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_CUBE_MAP, texnum); CHECKGLERROR unit->tcubemap = texnum; }
                break;
            }
        }
        else
        {
            if (unit->t2d) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_2D, 0); CHECKGLERROR unit->t2d = 0; }
            if (unit->t3d) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_3D, 0); CHECKGLERROR unit->t3d = 0; }
            if (unit->tcubemap) { GL_ActiveTexture(unitnum); qglBindTexture(GL_TEXTURE_CUBE_MAP, 0); CHECKGLERROR unit->tcubemap = 0; }
        }
    }
    unit->texture = tex;
}
 
void R_Mesh_ResetTextureState(void)
{
#if 0
    unsigned int unitnum;
    
    BACKENDACTIVECHECK
 
    for (unitnum = 0;unitnum < MAX_TEXTUREUNITS;unitnum++)
        R_Mesh_TexBind(unitnum, NULL);
#endif
}
 
void R_Mesh_PrepareVertices_Vertex3f(int numvertices, const float *vertex3f, const r_meshbuffer_t *vertexbuffer, int bufferoffset)
{
    // upload temporary vertexbuffer for this rendering
    if (!vertexbuffer)
        vertexbuffer = R_BufferData_Store(numvertices * sizeof(float[3]), (void *)vertex3f, R_BUFFERDATA_VERTEX, &bufferoffset);
    R_Mesh_VertexPointer(     3, GL_FLOAT        , sizeof(float[3])        , vertex3f  , vertexbuffer     , bufferoffset           );
    R_Mesh_ColorPointer(      4, GL_FLOAT        , sizeof(float[4])        , NULL      , NULL             , 0                      );
    R_Mesh_TexCoordPointer(0, 2, GL_FLOAT        , sizeof(float[2])        , NULL      , NULL             , 0                      );
    R_Mesh_TexCoordPointer(1, 3, GL_FLOAT        , sizeof(float[3])        , NULL      , NULL             , 0                      );
    R_Mesh_TexCoordPointer(2, 3, GL_FLOAT        , sizeof(float[3])        , NULL      , NULL             , 0                      );
    R_Mesh_TexCoordPointer(3, 3, GL_FLOAT        , sizeof(float[3])        , NULL      , NULL             , 0                      );
    R_Mesh_TexCoordPointer(4, 2, GL_FLOAT        , sizeof(float[2])        , NULL      , NULL             , 0                      );
    R_Mesh_TexCoordPointer(5, 2, GL_FLOAT        , sizeof(float[2])        , NULL      , NULL             , 0                      );
    R_Mesh_TexCoordPointer(6, 4, GL_UNSIGNED_BYTE, sizeof(unsigned char[4]), NULL      , NULL             , 0                      );
    R_Mesh_TexCoordPointer(7, 4, GL_UNSIGNED_BYTE, sizeof(unsigned char[4]), NULL      , NULL             , 0                      );
}
 
void R_Mesh_PrepareVertices_Generic_Arrays(int numvertices, const float *vertex3f, const float *color4f, const float *texcoord2f)
{
    r_meshbuffer_t *buffer_vertex3f = NULL;
    r_meshbuffer_t *buffer_color4f = NULL;
    r_meshbuffer_t *buffer_texcoord2f = NULL;
    int bufferoffset_vertex3f = 0;
    int bufferoffset_color4f = 0;
    int bufferoffset_texcoord2f = 0;
    if (color4f)
        buffer_color4f    = R_BufferData_Store(numvertices * sizeof(float[4]), color4f   , R_BUFFERDATA_VERTEX, &bufferoffset_color4f   );
    if (vertex3f)
        buffer_vertex3f   = R_BufferData_Store(numvertices * sizeof(float[3]), vertex3f  , R_BUFFERDATA_VERTEX, &bufferoffset_vertex3f  );
    if (texcoord2f)
        buffer_texcoord2f = R_BufferData_Store(numvertices * sizeof(float[2]), texcoord2f, R_BUFFERDATA_VERTEX, &bufferoffset_texcoord2f);
    R_Mesh_VertexPointer(     3, GL_FLOAT        , sizeof(float[3])        , vertex3f          , buffer_vertex3f          , bufferoffset_vertex3f          );
    R_Mesh_ColorPointer(      4, GL_FLOAT        , sizeof(float[4])        , color4f           , buffer_color4f           , bufferoffset_color4f           );
    R_Mesh_TexCoordPointer(0, 2, GL_FLOAT        , sizeof(float[2])        , texcoord2f        , buffer_texcoord2f        , bufferoffset_texcoord2f        );
    R_Mesh_TexCoordPointer(1, 3, GL_FLOAT        , sizeof(float[3])        , NULL              , NULL                     , 0                              );
    R_Mesh_TexCoordPointer(2, 3, GL_FLOAT        , sizeof(float[3])        , NULL              , NULL                     , 0                              );
    R_Mesh_TexCoordPointer(3, 3, GL_FLOAT        , sizeof(float[3])        , NULL              , NULL                     , 0                              );
    R_Mesh_TexCoordPointer(4, 2, GL_FLOAT        , sizeof(float[2])        , NULL              , NULL                     , 0                              );
    R_Mesh_TexCoordPointer(5, 2, GL_FLOAT        , sizeof(float[2])        , NULL              , NULL                     , 0                              );
    R_Mesh_TexCoordPointer(6, 4, GL_UNSIGNED_BYTE, sizeof(unsigned char[4]), NULL              , NULL                     , 0                              );
    R_Mesh_TexCoordPointer(7, 4, GL_UNSIGNED_BYTE, sizeof(unsigned char[4]), NULL              , NULL                     , 0                              );
}
 
void R_Mesh_PrepareVertices_Mesh_Arrays(int numvertices, const float *vertex3f, const float *svector3f, const float *tvector3f, const float *normal3f, const float *color4f, const float *texcoordtexture2f, const float *texcoordlightmap2f)
{
    r_meshbuffer_t *buffer_vertex3f = NULL;
    r_meshbuffer_t *buffer_color4f = NULL;
    r_meshbuffer_t *buffer_texcoordtexture2f = NULL;
    r_meshbuffer_t *buffer_svector3f = NULL;
    r_meshbuffer_t *buffer_tvector3f = NULL;
    r_meshbuffer_t *buffer_normal3f = NULL;
    r_meshbuffer_t *buffer_texcoordlightmap2f = NULL;
    int bufferoffset_vertex3f = 0;
    int bufferoffset_color4f = 0;
    int bufferoffset_texcoordtexture2f = 0;
    int bufferoffset_svector3f = 0;
    int bufferoffset_tvector3f = 0;
    int bufferoffset_normal3f = 0;
    int bufferoffset_texcoordlightmap2f = 0;
    if (color4f)
        buffer_color4f            = R_BufferData_Store(numvertices * sizeof(float[4]), color4f           , R_BUFFERDATA_VERTEX, &bufferoffset_color4f           );
    if (vertex3f)
        buffer_vertex3f           = R_BufferData_Store(numvertices * sizeof(float[3]), vertex3f          , R_BUFFERDATA_VERTEX, &bufferoffset_vertex3f          );
    if (svector3f)
        buffer_svector3f          = R_BufferData_Store(numvertices * sizeof(float[3]), svector3f         , R_BUFFERDATA_VERTEX, &bufferoffset_svector3f         );
    if (tvector3f)
        buffer_tvector3f          = R_BufferData_Store(numvertices * sizeof(float[3]), tvector3f         , R_BUFFERDATA_VERTEX, &bufferoffset_tvector3f         );
    if (normal3f)
        buffer_normal3f           = R_BufferData_Store(numvertices * sizeof(float[3]), normal3f          , R_BUFFERDATA_VERTEX, &bufferoffset_normal3f          );
    if (texcoordtexture2f)
        buffer_texcoordtexture2f  = R_BufferData_Store(numvertices * sizeof(float[2]), texcoordtexture2f , R_BUFFERDATA_VERTEX, &bufferoffset_texcoordtexture2f );
    if (texcoordlightmap2f)
        buffer_texcoordlightmap2f = R_BufferData_Store(numvertices * sizeof(float[2]), texcoordlightmap2f, R_BUFFERDATA_VERTEX, &bufferoffset_texcoordlightmap2f);
    R_Mesh_VertexPointer(     3, GL_FLOAT        , sizeof(float[3])        , vertex3f          , buffer_vertex3f          , bufferoffset_vertex3f          );
    R_Mesh_ColorPointer(      4, GL_FLOAT        , sizeof(float[4])        , color4f           , buffer_color4f           , bufferoffset_color4f           );
    R_Mesh_TexCoordPointer(0, 2, GL_FLOAT        , sizeof(float[2])        , texcoordtexture2f , buffer_texcoordtexture2f , bufferoffset_texcoordtexture2f );
    R_Mesh_TexCoordPointer(1, 3, GL_FLOAT        , sizeof(float[3])        , svector3f         , buffer_svector3f         , bufferoffset_svector3f         );
    R_Mesh_TexCoordPointer(2, 3, GL_FLOAT        , sizeof(float[3])        , tvector3f         , buffer_tvector3f         , bufferoffset_tvector3f         );
    R_Mesh_TexCoordPointer(3, 3, GL_FLOAT        , sizeof(float[3])        , normal3f          , buffer_normal3f          , bufferoffset_normal3f          );
    R_Mesh_TexCoordPointer(4, 2, GL_FLOAT        , sizeof(float[2])        , texcoordlightmap2f, buffer_texcoordlightmap2f, bufferoffset_texcoordlightmap2f);
    R_Mesh_TexCoordPointer(5, 2, GL_FLOAT        , sizeof(float[2])        , NULL              , NULL                     , 0                              );
    R_Mesh_TexCoordPointer(6, 4, GL_UNSIGNED_BYTE, sizeof(unsigned char[4]), NULL              , NULL                     , 0                              );
    R_Mesh_TexCoordPointer(7, 4, GL_UNSIGNED_BYTE, sizeof(unsigned char[4]), NULL              , NULL                     , 0                              );
}
 
void GL_BlendEquationSubtract(qbool negated)
{
    CHECKGLERROR
    if(negated)
    {
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            qglBlendEquation(GL_FUNC_REVERSE_SUBTRACT);CHECKGLERROR
            break;
        }
    }
    else
    {
        switch(vid.renderpath)
        {
        case RENDERPATH_GL32:
        case RENDERPATH_GLES2:
            qglBlendEquation(GL_FUNC_ADD);CHECKGLERROR
            break;
        }
    }
}