changed R_Mesh_TexCombine to use GL_COMBINE_ARB mode only when necessary

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@9567 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/gl_backend.c b/gl_backend.c
index 07fcfdbb3e92c7ab2dfcf4f4876fcb8b6373f7bd..4962e941ec2ecf5f7b487a202c1f08973be39cbc 100644 (file)
--- a/gl_backend.c
+++ b/gl_backend.c
@@ -101,6 +101,7 @@ typedef struct gltextureunit_s
        int arrayenabled;
        unsigned int arraycomponents;
        int rgbscale, alphascale;
+       int combine;
        int combinergb, combinealpha;
        // texmatrixenabled exists only to avoid unnecessary texmatrix compares
        int texmatrixenabled;
@@ -658,7 +659,6 @@ static void GL_BindEBO(int bufferobject)
 static void GL_Backend_ResetState(void)
 {
        unsigned int i;
-       gltextureunit_t *unit;
        memset(&gl_state, 0, sizeof(gl_state));
        gl_state.active = true;
        gl_state.depthtest = true;
@@ -713,16 +713,6 @@ static void GL_Backend_ResetState(void)
 
        gl_state.unit = MAX_TEXTUREUNITS;
        gl_state.clientunit = MAX_TEXTUREUNITS;
-       for (i = 0;i < MAX_TEXTUREUNITS;i++)
-       {
-               unit = gl_state.units + i;
-               unit->rgbscale = 1;
-               unit->alphascale = 1;
-               unit->combinergb = GL_MODULATE;
-               unit->combinealpha = GL_MODULATE;
-               unit->matrix = identitymatrix;
-       }
-
        for (i = 0;i < vid.teximageunits;i++)
        {
                GL_ActiveTexture(i);
@@ -768,30 +758,7 @@ static void GL_Backend_ResetState(void)
                qglMatrixMode(GL_TEXTURE);CHECKGLERROR
                qglLoadIdentity();CHECKGLERROR
                qglMatrixMode(GL_MODELVIEW);CHECKGLERROR
-               if (gl_combine.integer)
-               {
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_RGB_ARB, GL_MODULATE);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_RGB_ARB, GL_TEXTURE);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_SOURCE1_RGB_ARB, GL_PREVIOUS_ARB);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_SOURCE2_RGB_ARB, GL_TEXTURE);CHECKGLERROR // for GL_INTERPOLATE_ARB mode
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_RGB_ARB, GL_SRC_COLOR);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_RGB_ARB, GL_SRC_COLOR);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_OPERAND2_RGB_ARB, GL_SRC_ALPHA);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_COMBINE_ALPHA_ARB, GL_MODULATE);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_SOURCE0_ALPHA_ARB, GL_TEXTURE);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_SOURCE1_ALPHA_ARB, GL_PREVIOUS_ARB);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_SOURCE2_ALPHA_ARB, GL_CONSTANT_ARB);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_OPERAND0_ALPHA_ARB, GL_SRC_ALPHA);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_OPERAND1_ALPHA_ARB, GL_SRC_ALPHA);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_OPERAND2_ALPHA_ARB, GL_SRC_ALPHA);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_RGB_SCALE_ARB, 1);CHECKGLERROR
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_ALPHA_SCALE, 1);CHECKGLERROR
-               }
-               else
-               {
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);CHECKGLERROR
-               }
+               qglTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);CHECKGLERROR
                CHECKGLERROR
        }
        CHECKGLERROR
@@ -1809,17 +1776,25 @@ void R_Mesh_TexCombine(unsigned int unitnum, int combinergb, int combinealpha, i
 {
        gltextureunit_t *unit = gl_state.units + unitnum;
        CHECKGLERROR
-       if (gl_combine.integer)
-       {
-               // GL_ARB_texture_env_combine
-               if (!combinergb)
-                       combinergb = GL_MODULATE;
-               if (!combinealpha)
-                       combinealpha = GL_MODULATE;
-               if (!rgbscale)
-                       rgbscale = 1;
-               if (!alphascale)
-                       alphascale = 1;
+       if (!combinergb)
+               combinergb = GL_MODULATE;
+       if (!combinealpha)
+               combinealpha = GL_MODULATE;
+       if (!rgbscale)
+               rgbscale = 1;
+       if (!alphascale)
+               alphascale = 1;
+       if (combinergb != combinealpha || rgbscale != 1 || alphascale != 1 || combinergb == GL_DOT3_RGBA_ARB || combinergb == GL_DOT3_RGB_ARB)
+       {
+               if (combinergb == GL_DECAL)
+                       combinergb = GL_INTERPOLATE_ARB;
+               if (unit->combine != GL_COMBINE_ARB)
+               {
+                       unit->combine = GL_COMBINE_ARB;
+                       GL_ActiveTexture(unitnum);
+                       qglTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_COMBINE_ARB);CHECKGLERROR
+                       qglTexEnvi(GL_TEXTURE_ENV, GL_SOURCE2_RGB_ARB, GL_TEXTURE);CHECKGLERROR // for GL_INTERPOLATE_ARB mode
+               }
                if (unit->combinergb != combinergb)
                {
                        unit->combinergb = combinergb;
@@ -1834,25 +1809,24 @@ void R_Mesh_TexCombine(unsigned int unitnum, int combinergb, int combinealpha, i
                }
                if (unit->rgbscale != rgbscale)
                {
+                       unit->rgbscale = rgbscale;
                        GL_ActiveTexture(unitnum);
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_RGB_SCALE_ARB, (unit->rgbscale = rgbscale));CHECKGLERROR
+                       qglTexEnvi(GL_TEXTURE_ENV, GL_RGB_SCALE_ARB, unit->rgbscale);CHECKGLERROR
                }
                if (unit->alphascale != alphascale)
                {
+                       unit->alphascale = alphascale;
                        GL_ActiveTexture(unitnum);
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_ALPHA_SCALE, (unit->alphascale = alphascale));CHECKGLERROR
+                       qglTexEnvi(GL_TEXTURE_ENV, GL_ALPHA_SCALE, unit->alphascale);CHECKGLERROR
                }
        }
        else
        {
-               // normal GL texenv
-               if (!combinergb)
-                       combinergb = GL_MODULATE;
-               if (unit->combinergb != combinergb)
+               if (unit->combine != combinergb)
                {
-                       unit->combinergb = combinergb;
+                       unit->combine = combinergb;
                        GL_ActiveTexture(unitnum);
-                       qglTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, unit->combinergb);CHECKGLERROR
+                       qglTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, unit->combine);CHECKGLERROR
                }
        }
 }