the beginnings of VBO support in the rendering backend

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@7042 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/gl_backend.c b/gl_backend.c
index a7e0dd46f6882c5d0f9cc47c6aeb58003656d6b7..b8e255d9872518d187771fa4f91e7731dcae419f 100644 (file)
--- a/gl_backend.c
+++ b/gl_backend.c
@@ -330,10 +330,12 @@ void GL_SetupView_Mode_Ortho (double x1, double y1, double x2, double y2, double
 
 typedef struct gltextureunit_s
 {
+       const void *pointer_texcoord;
+       size_t pointer_texcoord_offset;
+       int pointer_texcoord_buffer;
        int t1d, t2d, t3d, tcubemap;
        int arrayenabled;
        unsigned int arraycomponents;
-       const void *pointer_texcoord;
        int rgbscale, alphascale;
        int combinergb, combinealpha;
        // FIXME: add more combine stuff
@@ -361,11 +363,40 @@ static struct gl_state_s
        float color4f[4];
        int lockrange_first;
        int lockrange_count;
+       int vertexbufferobject;
+       int elementbufferobject;
+       qboolean pointer_color_enabled;
        const void *pointer_vertex;
        const void *pointer_color;
+       size_t pointer_vertex_offset;
+       size_t pointer_color_offset;
+       int pointer_vertex_buffer;
+       int pointer_color_buffer;
 }
 gl_state;
 
+static void GL_BindVBO(int bufferobject)
+{
+       if (gl_state.vertexbufferobject != bufferobject)
+       {
+               gl_state.vertexbufferobject = bufferobject;
+               CHECKGLERROR
+               qglBindBufferARB(GL_ARRAY_BUFFER_ARB, bufferobject);
+               CHECKGLERROR
+       }
+}
+
+static void GL_BindEBO(int bufferobject)
+{
+       if (gl_state.elementbufferobject != bufferobject)
+       {
+               gl_state.elementbufferobject = bufferobject;
+               CHECKGLERROR
+               qglBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, bufferobject);
+               CHECKGLERROR
+       }
+}
+
 void GL_SetupTextureState(void)
 {
        unsigned int i;
@@ -383,6 +414,8 @@ void GL_SetupTextureState(void)
                unit->arrayenabled = false;
                unit->arraycomponents = 0;
                unit->pointer_texcoord = NULL;
+               unit->pointer_texcoord_buffer = 0;
+               unit->pointer_texcoord_offset = 0;
                unit->rgbscale = 1;
                unit->alphascale = 1;
                unit->combinergb = GL_MODULATE;
@@ -409,6 +442,7 @@ void GL_SetupTextureState(void)
        for (i = 0;i < backendarrayunits;i++)
        {
                GL_ClientActiveTexture(i);
+               GL_BindVBO(0);
                qglTexCoordPointer(2, GL_FLOAT, sizeof(float[2]), NULL);CHECKGLERROR
                qglDisableClientState(GL_TEXTURE_COORD_ARRAY);CHECKGLERROR
        }
@@ -471,8 +505,6 @@ void GL_Backend_ResetState(void)
        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.pointer_vertex = NULL;
-       gl_state.pointer_color = NULL;
        gl_state.cullface = GL_FRONT; // quake is backwards, this culls back faces
        gl_state.cullfaceenable = true;
 
@@ -489,6 +521,12 @@ void GL_Backend_ResetState(void)
        qglEnable(GL_DEPTH_TEST);CHECKGLERROR
        qglDepthMask(gl_state.depthmask);CHECKGLERROR
 
+       if (gl_support_arb_vertex_buffer_object)
+       {
+               qglBindBufferARB(GL_ARRAY_BUFFER_ARB, 0);
+               qglBindBufferARB(GL_ELEMENT_ARRAY_BUFFER_ARB, 0);
+       }
+
        qglVertexPointer(3, GL_FLOAT, sizeof(float[3]), NULL);CHECKGLERROR
        qglEnableClientState(GL_VERTEX_ARRAY);CHECKGLERROR
 
@@ -647,7 +685,7 @@ void GL_ColorMask(int r, int g, int b, int a)
 
 void GL_Color(float cr, float cg, float cb, float ca)
 {
-       if (gl_state.pointer_color || gl_state.color4f[0] != cr || gl_state.color4f[1] != cg || gl_state.color4f[2] != cb || gl_state.color4f[3] != 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;
@@ -831,6 +869,8 @@ void GL_Backend_RenumberElements(int *out, int count, const int *in, int offset)
 int paranoidblah = 0;
 void R_Mesh_Draw(int firstvertex, int numvertices, int numtriangles, const int *elements)
 {
+       int bufferobject = 0;
+       size_t offset = 0;
        unsigned int numelements = numtriangles * 3;
        if (numvertices < 3 || numtriangles < 1)
        {
@@ -844,18 +884,25 @@ void R_Mesh_Draw(int firstvertex, int numvertices, int numtriangles, const int *
        {
                unsigned int i, j, size;
                const int *p;
+               // note: there's no validation done here on buffer objects because it
+               // is somewhat difficult to get at the data, and gl_paranoid can be
+               // used without buffer objects if the need arises
+               // (the data could be gotten using glMapBuffer but it would be very
+               //  slow due to uncachable video memory reads)
                if (!qglIsEnabled(GL_VERTEX_ARRAY))
                        Con_Print("R_Mesh_Draw: vertex array not enabled\n");
                CHECKGLERROR
-               for (j = 0, size = numvertices * 3, p = (int *)((float *)gl_state.pointer_vertex + firstvertex * 3);j < size;j++, p++)
-                       paranoidblah += *p;
-               if (gl_state.pointer_color)
+               if (gl_state.pointer_vertex)
+                       for (j = 0, size = numvertices * 3, p = (int *)((float *)gl_state.pointer_vertex + firstvertex * 3);j < size;j++, p++)
+                               paranoidblah += *p;
+               if (gl_state.pointer_color_enabled)
                {
                        if (!qglIsEnabled(GL_COLOR_ARRAY))
                                Con_Print("R_Mesh_Draw: color array set but not enabled\n");
                        CHECKGLERROR
-                       for (j = 0, size = numvertices * 4, p = (int *)((float *)gl_state.pointer_color + firstvertex * 4);j < size;j++, p++)
-                               paranoidblah += *p;
+                       if (gl_state.pointer_color && gl_state.pointer_color_enabled)
+                               for (j = 0, size = numvertices * 4, p = (int *)((float *)gl_state.pointer_color + firstvertex * 4);j < size;j++, p++)
+                                       paranoidblah += *p;
                }
                for (i = 0;i < backendarrayunits;i++)
                {
@@ -865,8 +912,9 @@ void R_Mesh_Draw(int firstvertex, int numvertices, int numtriangles, const int *
                                if (!qglIsEnabled(GL_TEXTURE_COORD_ARRAY))
                                        Con_Print("R_Mesh_Draw: texcoord array set but not enabled\n");
                                CHECKGLERROR
-                               for (j = 0, size = numvertices * gl_state.units[i].arraycomponents, p = (int *)((float *)gl_state.units[i].pointer_texcoord + firstvertex * gl_state.units[i].arraycomponents);j < size;j++, p++)
-                                       paranoidblah += *p;
+                               if (gl_state.units[i].pointer_texcoord && gl_state.units[i].arrayenabled)
+                                       for (j = 0, size = numvertices * gl_state.units[i].arraycomponents, p = (int *)((float *)gl_state.units[i].pointer_texcoord + firstvertex * gl_state.units[i].arraycomponents);j < size;j++, p++)
+                                               paranoidblah += *p;
                        }
                }
                for (i = 0;i < (unsigned int) numtriangles * 3;i++)
@@ -891,7 +939,7 @@ void R_Mesh_Draw(int firstvertex, int numvertices, int numtriangles, const int *
                        {
                                for (j = 0;j < backendarrayunits;j++)
                                {
-                                       if (gl_state.units[j].pointer_texcoord)
+                                       if (gl_state.units[j].pointer_texcoord && gl_state.units[j].arrayenabled)
                                        {
                                                if (backendarrayunits > 1)
                                                {
@@ -941,7 +989,7 @@ void R_Mesh_Draw(int firstvertex, int numvertices, int numtriangles, const int *
                                                }
                                        }
                                }
-                               if (gl_state.pointer_color)
+                               if (gl_state.pointer_color && gl_state.pointer_color_enabled)
                                {
                                        p = ((const GLfloat *)(gl_state.pointer_color)) + elements[i] * 4;
                                        qglColor4f(p[0], p[1], p[2], p[3]);
@@ -965,12 +1013,14 @@ void R_Mesh_Draw(int firstvertex, int numvertices, int numtriangles, const int *
                }
                else if (gl_mesh_drawrangeelements.integer && qglDrawRangeElements != NULL)
                {
-                       qglDrawRangeElements(GL_TRIANGLES, firstvertex, firstvertex + numvertices, numelements, GL_UNSIGNED_INT, elements);
+                       GL_BindEBO(bufferobject);
+                       qglDrawRangeElements(GL_TRIANGLES, firstvertex, firstvertex + numvertices, numelements, GL_UNSIGNED_INT, bufferobject ? (void *)offset : elements);
                        CHECKGLERROR
                }
                else
                {
-                       qglDrawElements(GL_TRIANGLES, numelements, GL_UNSIGNED_INT, elements);
+                       GL_BindEBO(bufferobject);
+                       qglDrawElements(GL_TRIANGLES, numelements, GL_UNSIGNED_INT, bufferobject ? (void *)offset : elements);
                        CHECKGLERROR
                }
        }
@@ -1048,50 +1098,65 @@ void R_Mesh_Matrix(const matrix4x4_t *matrix)
 
 void R_Mesh_VertexPointer(const float *vertex3f)
 {
-       if (gl_state.pointer_vertex != vertex3f)
+       int bufferobject = 0;
+       size_t offset = 0;
+       if (gl_state.pointer_vertex != vertex3f || gl_state.pointer_vertex_buffer != bufferobject || gl_state.pointer_vertex_offset != offset)
        {
                gl_state.pointer_vertex = vertex3f;
+               gl_state.pointer_vertex_buffer = bufferobject;
+               gl_state.pointer_vertex_offset = offset;
                CHECKGLERROR
-               qglVertexPointer(3, GL_FLOAT, sizeof(float[3]), gl_state.pointer_vertex);
-               CHECKGLERROR
+               GL_BindVBO(bufferobject);
+               qglVertexPointer(3, GL_FLOAT, sizeof(float[3]), bufferobject ? (void *)offset : vertex3f);CHECKGLERROR
        }
 }
 
 void R_Mesh_ColorPointer(const float *color4f)
 {
-       if (gl_state.pointer_color != color4f)
+       int bufferobject = 0;
+       size_t offset = 0;
+       if (color4f || bufferobject)
        {
-               CHECKGLERROR
-               if (!gl_state.pointer_color)
+               // caller wants color array enabled
+               if (!gl_state.pointer_color_enabled)
                {
+                       gl_state.pointer_color_enabled = true;
+                       CHECKGLERROR
                        qglEnableClientState(GL_COLOR_ARRAY);CHECKGLERROR
                }
-               else if (!color4f)
+               if (gl_state.pointer_color != color4f || gl_state.pointer_color_buffer != bufferobject || gl_state.pointer_color_offset != offset)
                {
+                       gl_state.pointer_color = color4f;
+                       gl_state.pointer_color_buffer = bufferobject;
+                       gl_state.pointer_color_offset = offset;
+                       CHECKGLERROR
+                       GL_BindVBO(bufferobject);
+                       qglColorPointer(4, GL_FLOAT, sizeof(float[4]), bufferobject ? (void *)offset : color4f);CHECKGLERROR
+               }
+       }
+       else
+       {
+               // caller wants color array disabled
+               if (gl_state.pointer_color_enabled)
+               {
+                       gl_state.pointer_color_enabled = false;
+                       CHECKGLERROR
                        qglDisableClientState(GL_COLOR_ARRAY);CHECKGLERROR
                        // when color array is on the glColor gets trashed, set it again
                        qglColor4f(gl_state.color4f[0], gl_state.color4f[1], gl_state.color4f[2], gl_state.color4f[3]);CHECKGLERROR
                }
-               gl_state.pointer_color = color4f;
-               qglColorPointer(4, GL_FLOAT, sizeof(float[4]), gl_state.pointer_color);CHECKGLERROR
        }
 }
 
 void R_Mesh_TexCoordPointer(unsigned int unitnum, unsigned int numcomponents, const float *texcoord)
 {
+       int bufferobject = 0;
+       size_t offset;
        gltextureunit_t *unit = gl_state.units + unitnum;
        // update array settings
        CHECKGLERROR
-       if (texcoord)
+       if (texcoord || bufferobject)
        {
-               // texcoord array
-               if (unit->pointer_texcoord != texcoord || unit->arraycomponents != numcomponents)
-               {
-                       unit->pointer_texcoord = texcoord;
-                       unit->arraycomponents = numcomponents;
-                       GL_ClientActiveTexture(unitnum);
-                       qglTexCoordPointer(unit->arraycomponents, GL_FLOAT, sizeof(float) * unit->arraycomponents, unit->pointer_texcoord);CHECKGLERROR
-               }
                // texture array unit is enabled, enable the array
                if (!unit->arrayenabled)
                {
@@ -1099,6 +1164,17 @@ void R_Mesh_TexCoordPointer(unsigned int unitnum, unsigned int numcomponents, co
                        GL_ClientActiveTexture(unitnum);
                        qglEnableClientState(GL_TEXTURE_COORD_ARRAY);CHECKGLERROR
                }
+               // texcoord array
+               if (unit->pointer_texcoord != texcoord || unit->pointer_texcoord_buffer != bufferobject || unit->pointer_texcoord_offset != offset || unit->arraycomponents != numcomponents)
+               {
+                       unit->pointer_texcoord = texcoord;
+                       unit->pointer_texcoord_buffer = bufferobject;
+                       unit->pointer_texcoord_offset = offset;
+                       unit->arraycomponents = numcomponents;
+                       GL_ClientActiveTexture(unitnum);
+                       GL_BindVBO(bufferobject);
+                       qglTexCoordPointer(unit->arraycomponents, GL_FLOAT, sizeof(float) * unit->arraycomponents, bufferobject ? (void *)offset : texcoord);CHECKGLERROR
+               }
        }
        else
        {