support slope-dependent shadowmap biasing with polygon offset

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@9331 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/r_shadow.c b/r_shadow.c
index 5109e5b0dd9f3a616204dc1d7eb67c9e958cc804..57d7bcea0d4d0441926bcb3533b4aa157a1e3648 100644 (file)
--- a/r_shadow.c
+++ b/r_shadow.c
@@ -298,6 +298,8 @@ cvar_t r_shadow_shadowmapping_lod_scale = {CVAR_SAVE, "r_shadow_shadowmapping_lo
 cvar_t r_shadow_shadowmapping_bordersize = {CVAR_SAVE, "r_shadow_shadowmapping_bordersize", "4", "shadowmap size bias for filtering"};
 cvar_t r_shadow_shadowmapping_nearclip = {CVAR_SAVE, "r_shadow_shadowmapping_nearclip", "1", "shadowmap nearclip in world units"};
 cvar_t r_shadow_shadowmapping_bias = {CVAR_SAVE, "r_shadow_shadowmapping_bias", "0.03", "shadowmap bias parameter (this is multiplied by nearclip * 1024 / lodsize)"};
+cvar_t r_shadow_shadowmapping_polygonfactor = {CVAR_SAVE, "r_shadow_shadowmapping_polygonfactor", "2", "slope-dependent shadowmapping bias"};
+cvar_t r_shadow_shadowmapping_polygonoffset = {CVAR_SAVE, "r_shadow_shadowmapping_polygonoffset", "0", "constant shadowmapping bias"};
 cvar_t r_shadow_culltriangles = {0, "r_shadow_culltriangles", "1", "performs more expensive tests to remove unnecessary triangles of lit surfaces"};
 cvar_t r_shadow_polygonfactor = {0, "r_shadow_polygonfactor", "0", "how much to enlarge shadow volume polygons when rendering (should be 0!)"};
 cvar_t r_shadow_polygonoffset = {0, "r_shadow_polygonoffset", "1", "how much to push shadow volumes into the distance when rendering, to reduce chances of zfighting artifacts (should not be less than 0)"};
@@ -696,6 +698,8 @@ void R_Shadow_Init(void)
        Cvar_RegisterVariable(&r_shadow_shadowmapping_bordersize);
        Cvar_RegisterVariable(&r_shadow_shadowmapping_nearclip);
        Cvar_RegisterVariable(&r_shadow_shadowmapping_bias);
+       Cvar_RegisterVariable(&r_shadow_shadowmapping_polygonfactor);
+       Cvar_RegisterVariable(&r_shadow_shadowmapping_polygonoffset);
        Cvar_RegisterVariable(&r_shadow_culltriangles);
        Cvar_RegisterVariable(&r_shadow_polygonfactor);
        Cvar_RegisterVariable(&r_shadow_polygonoffset);
@@ -2054,7 +2058,7 @@ void R_Shadow_RenderMode_ShadowMap(int side, qboolean clear, int size)
                qglClearColor(1,1,1,1);CHECKGLERROR
        }
        CHECKGLERROR
-       GL_PolygonOffset(0, 0);
+       GL_PolygonOffset(r_shadow_shadowmapping_polygonfactor.value, r_shadow_shadowmapping_polygonoffset.value);
        GL_DepthMask(true);
        GL_DepthTest(true);
        qglClearDepth(1);