only issue one clear for 2D/rect shadowmaps

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@9796 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/r_shadow.c b/r_shadow.c
index 56c387f986c6d9b1d86581d9ea136244f2a8f2ee..d8acc0089ec5033dc403715e4a18d1bee1d5de2d 100644 (file)
--- a/r_shadow.c
+++ b/r_shadow.c
@@ -2053,7 +2053,7 @@ static void R_Shadow_MakeVSDCT(void)
        r_shadow_shadowmapvsdcttexture = R_LoadTextureCubeMap(r_shadow_texturepool, "shadowmapvsdct", 1, data, TEXTYPE_RGBA, TEXF_FORCENEAREST | TEXF_CLAMP | TEXF_ALPHA, NULL);
 }
 
-void R_Shadow_RenderMode_ShadowMap(int side, qboolean clear, int size)
+void R_Shadow_RenderMode_ShadowMap(int side, int clear, int size)
 {
        int status;
        int maxsize;
@@ -2194,20 +2194,31 @@ void R_Shadow_RenderMode_ShadowMap(int side, qboolean clear, int size)
 
 init_done:
        R_SetViewport(&viewport);
-       GL_Scissor(viewport.x, viewport.y, viewport.width, viewport.height);
        if(r_shadow_rendermode == R_SHADOW_RENDERMODE_SHADOWMAP2D || r_shadow_rendermode == R_SHADOW_RENDERMODE_SHADOWMAPRECTANGLE)
        {
-               int flipped = (side&1)^(side>>2);
+               int flipped = (side & 1) ^ (side >> 2);
                r_refdef.view.cullface_front = flipped ? r_shadow_cullface_back : r_shadow_cullface_front;
                r_refdef.view.cullface_back = flipped ? r_shadow_cullface_front : r_shadow_cullface_back;
                GL_CullFace(r_refdef.view.cullface_back);
+               if ((clear & ((2 << side) - 1)) == (1 << side)) // only clear if the side is the first in the mask
+               {
+                       // get tightest scissor rectangle that encloses all viewports in the clear mask
+                       int x1 = clear & 0x15 ? 0 : size;
+                       int x2 = clear & 0x2A ? 2 * size : size;
+                       int y1 = clear & 0x03 ? 0 : (clear & 0xC ? size : 2 * size);
+                       int y2 = clear & 0x30 ? 3 * size : (clear & 0xC ? 2 * size : size);
+                       GL_Scissor(x1, y1, x2 - x1, y2 - y1);
+                       GL_Clear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT |  GL_STENCIL_BUFFER_BIT);
+               }
+               GL_Scissor(viewport.x, viewport.y, viewport.width, viewport.height);
        }
        else if(r_shadow_rendermode == R_SHADOW_RENDERMODE_SHADOWMAPCUBESIDE)
        {
                qglFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB + side, R_GetTexture(r_shadow_shadowmapcubetexture[r_shadow_shadowmaplod]), 0);CHECKGLERROR
+               GL_Scissor(viewport.x, viewport.y, viewport.width, viewport.height);
+               if (clear)
+                       GL_Clear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT |  GL_STENCIL_BUFFER_BIT);
        }
-       if (clear)
-               qglClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT |  GL_STENCIL_BUFFER_BIT);
        CHECKGLERROR
 }
 
@@ -3793,7 +3804,7 @@ void R_Shadow_DrawLight(rtlight_t *rtlight)
                // render shadow casters into 6 sided depth texture
                for (side = 0;side < 6;side++) if (receivermask & (1 << side))
                {
-                       R_Shadow_RenderMode_ShadowMap(side, true, size);
+                       R_Shadow_RenderMode_ShadowMap(side, receivermask, size);
                        if (! (castermask & (1 << side))) continue;
                        if (numsurfaces)
                                R_Shadow_DrawWorldShadow_ShadowMap(numsurfaces, surfacelist, shadowtrispvs, surfacesides);
@@ -3815,7 +3826,7 @@ void R_Shadow_DrawLight(rtlight_t *rtlight)
                {
                        for (side = 0;side < 6;side++) if ((receivermask & castermask) & (1 << side))
                        {
-                               R_Shadow_RenderMode_ShadowMap(side, false, size);
+                               R_Shadow_RenderMode_ShadowMap(side, 0, size);
                                for (i = 0;i < numshadowentities_noselfshadow;i++) if (entitysides_noselfshadow[i] & (1 << side))
                                        R_Shadow_DrawEntityShadow(shadowentities_noselfshadow[i]);
                        }