added r_transparentdepthmasking cvar (defaults to 1), this causes alpha

fading of opaque materials to look much better, while still not altering
transparent materials (like blended tree foliage - but that should be
alpha test anyway)

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@9601 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/gl_rmain.c b/gl_rmain.c
index 2bb2e5e8935dbab2b871d1b2032ae1687c61deea..43bead91fe0c72833f6b1864c3e744fa39aa6893 100644 (file)
--- a/gl_rmain.c
+++ b/gl_rmain.c
@@ -95,6 +95,7 @@ cvar_t r_polygonoffset_decals_factor = {0, "r_polygonoffset_decals_factor", "0",
 cvar_t r_polygonoffset_decals_offset = {0, "r_polygonoffset_decals_offset", "-14", "biases depth values of decals to prevent z-fighting artifacts"};
 cvar_t r_fog_exp2 = {0, "r_fog_exp2", "0", "uses GL_EXP2 fog (as in Nehahra) rather than realistic GL_EXP fog"};
 cvar_t r_drawfog = {CVAR_SAVE, "r_drawfog", "1", "allows one to disable fog rendering"};
+cvar_t r_transparentdepthmasking = {CVAR_SAVE, "r_transparentdepthmasking", "1", "enables depth writes on transparent meshes whose materially is normally opaque, this prevents seeing the inside of a transparent mesh"};
 
 cvar_t gl_fogenable = {0, "gl_fogenable", "0", "nehahra fog enable (for Nehahra compatibility only)"};
 cvar_t gl_fogdensity = {0, "gl_fogdensity", "0.25", "nehahra fog density (recommend values below 0.1) (for Nehahra compatibility only)"};
@@ -3337,6 +3338,7 @@ void GL_Main_Init(void)
        Cvar_RegisterVariable(&r_polygonoffset_decals_offset);
        Cvar_RegisterVariable(&r_fog_exp2);
        Cvar_RegisterVariable(&r_drawfog);
+       Cvar_RegisterVariable(&r_transparentdepthmasking);
        Cvar_RegisterVariable(&r_textureunits);
        Cvar_RegisterVariable(&gl_combine);
        Cvar_RegisterVariable(&r_glsl);
@@ -6079,6 +6081,8 @@ texture_t *R_GetCurrentTexture(texture_t *t)
        }
        else
                t->currentmaterialflags &= ~(MATERIALFLAG_REFRACTION | MATERIALFLAG_WATERSHADER);
+       if ((t->currentmaterialflags & (MATERIALFLAG_BLENDED | MATERIALFLAG_NODEPTHTEST)) == MATERIALFLAG_BLENDED && r_transparentdepthmasking.integer && !(t->basematerialflags & MATERIALFLAG_BLENDED))
+               t->currentmaterialflags |= MATERIALFLAG_TRANSDEPTH;
 
        // there is no tcmod
        if (t->currentmaterialflags & MATERIALFLAG_WATERSCROLL)
@@ -8214,6 +8218,51 @@ static void R_DrawSurface_TransparentCallback(const entity_render_t *ent, const
                }
        }
 
+       if (r_transparentdepthmasking.integer)
+       {
+               qboolean setup = false;
+               for (i = 0;i < numsurfaces;i = j)
+               {
+                       j = i + 1;
+                       surface = rsurface.modelsurfaces + surfacelist[i];
+                       texture = surface->texture;
+                       rsurface.texture = R_GetCurrentTexture(texture);
+                       rsurface.uselightmaptexture = surface->lightmaptexture != NULL;
+                       // scan ahead until we find a different texture
+                       endsurface = min(i + 1024, numsurfaces);
+                       texturenumsurfaces = 0;
+                       texturesurfacelist[texturenumsurfaces++] = surface;
+                       for (;j < endsurface;j++)
+                       {
+                               surface = rsurface.modelsurfaces + surfacelist[j];
+                               if (texture != surface->texture || rsurface.uselightmaptexture != (surface->lightmaptexture != NULL))
+                                       break;
+                               texturesurfacelist[texturenumsurfaces++] = surface;
+                       }
+                       if (!(rsurface.texture->currentmaterialflags & MATERIALFLAG_TRANSDEPTH))
+                               continue;
+                       // render the range of surfaces as depth
+                       if (!setup)
+                       {
+                               setup = true;
+                               GL_ColorMask(0,0,0,0);
+                               GL_Color(1,1,1,1);
+                               GL_DepthTest(true);
+                               GL_BlendFunc(GL_ONE, GL_ZERO);
+                               GL_DepthMask(true);
+                               GL_AlphaTest(false);
+                               R_Mesh_ColorPointer(NULL, 0, 0);
+                               R_Mesh_ResetTextureState();
+                               R_SetupDepthOrShadowShader();
+                       }
+                       RSurf_SetupDepthAndCulling();
+                       RSurf_PrepareVerticesForBatch(false, false, texturenumsurfaces, texturesurfacelist);
+                       RSurf_DrawBatch_Simple(texturenumsurfaces, texturesurfacelist);
+               }
+               if (setup)
+                       GL_ColorMask(r_refdef.view.colormask[0], r_refdef.view.colormask[1], r_refdef.view.colormask[2], 1);
+       }
+
        for (i = 0;i < numsurfaces;i = j)
        {
                j = i + 1;

diff --git a/model_brush.h b/model_brush.h
index ffe9599fc5efa1b6454d152a9d60212e19ed7dac..0463d74d1eedc3a8fe65f79ff5143f250b77dda5 100644 (file)
--- a/model_brush.h
+++ b/model_brush.h
@@ -110,6 +110,8 @@ mplane_t;
 #define MATERIALFLAG_MODELLIGHT_DIRECTIONAL 8388608
 // causes RSurf_GetCurrentTexture to leave alone certain fields
 #define MATERIALFLAG_CUSTOMSURFACE 16777216
+// causes MATERIALFLAG_BLENDED to render a depth pass before rendering, hiding backfaces and other hidden geometry
+#define MATERIALFLAG_TRANSDEPTH 33554432
 // combined mask of all attributes that require depth sorted rendering
 #define MATERIALFLAGMASK_DEPTHSORTED (MATERIALFLAG_BLENDED | MATERIALFLAG_NODEPTHTEST)
 // combined mask of all attributes that cause some sort of transparency