cast shadows from frontfaces instead of backfaces

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@2548 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/r_shadow.c b/r_shadow.c
index 65a1dfe14d2d358cb2e226ce41695792b9c20510..94b09b302939797194d7058ab609ce5ce10280f6 100644 (file)
--- a/r_shadow.c
+++ b/r_shadow.c
@@ -90,6 +90,7 @@ void R_Shadow_Volume(int numverts, int numtris, float *vertex, int *elements, in
                Con_Printf("R_Shadow_Volume: projectdistance %f\n");
                return;
        }
+       projectdistance = lightradius;
 // terminology:
 //
 // frontface:
@@ -133,10 +134,10 @@ void R_Shadow_Volume(int numverts, int numtris, float *vertex, int *elements, in
        // the unprojected vertices and these projected vertices
        for (i = 0, v0 = vertex, v1 = vertex + numverts * 4;i < numverts;i++, v0 += 4, v1 += 4)
        {
-#if 1
-               v1[0] = v0[0] + 50.0f * (v0[0] - relativelightorigin[0]);
-               v1[1] = v0[1] + 50.0f * (v0[1] - relativelightorigin[1]);
-               v1[2] = v0[2] + 50.0f * (v0[2] - relativelightorigin[2]);
+#if 0
+               v1[0] = v0[0] + 250.0f * (v0[0] - relativelightorigin[0]);
+               v1[1] = v0[1] + 250.0f * (v0[1] - relativelightorigin[1]);
+               v1[2] = v0[2] + 250.0f * (v0[2] - relativelightorigin[2]);
 #elif 0
                VectorSubtract(v0, relativelightorigin, temp);
                f = lightradius / sqrt(DotProduct(temp,temp));
@@ -210,6 +211,66 @@ void R_Shadow_Volume(int numverts, int numtris, float *vertex, int *elements, in
        // also create front and back caps for shadow volume
        for (i = 0, e = elements, n = neighbors;i < numtris;i++, e += 3, n += 3)
        {
+#if 1
+               if (trianglefacinglight[i])
+               {
+                       // triangle is backface and therefore casts shadow,
+                       // output front and back caps for shadow volume
+#if 1
+                       // front cap
+                       out[0] = e[0];
+                       out[1] = e[1];
+                       out[2] = e[2];
+                       // rear cap (with flipped winding order)
+                       out[3] = e[0] + numverts;
+                       out[4] = e[2] + numverts;
+                       out[5] = e[1] + numverts;
+                       out += 6;
+                       tris += 2;
+#elif 1
+                       // rear cap
+                       out[0] = e[0] + numverts;
+                       out[1] = e[2] + numverts;
+                       out[2] = e[1] + numverts;
+                       out += 3;
+                       tris += 1;
+#endif
+                       // check the edges
+                       if (n[0] < 0 || !trianglefacinglight[n[0]])
+                       {
+                               out[0] = e[1];
+                               out[1] = e[0];
+                               out[2] = e[0] + numverts;
+                               out[3] = e[1];
+                               out[4] = e[0] + numverts;
+                               out[5] = e[1] + numverts;
+                               out += 6;
+                               tris += 2;
+                       }
+                       if (n[1] < 0 || !trianglefacinglight[n[1]])
+                       {
+                               out[0] = e[2];
+                               out[1] = e[1];
+                               out[2] = e[1] + numverts;
+                               out[3] = e[2];
+                               out[4] = e[1] + numverts;
+                               out[5] = e[2] + numverts;
+                               out += 6;
+                               tris += 2;
+                       }
+                       if (n[2] < 0 || !trianglefacinglight[n[2]])
+                       {
+                               out[0] = e[0];
+                               out[1] = e[2];
+                               out[2] = e[2] + numverts;
+                               out[3] = e[0];
+                               out[4] = e[2] + numverts;
+                               out[5] = e[0] + numverts;
+                               out += 6;
+                               tris += 2;
+                       }
+               }
+#else
                if (!trianglefacinglight[i])
                {
                        // triangle is backface and therefore casts shadow,
@@ -268,6 +329,7 @@ void R_Shadow_Volume(int numverts, int numtris, float *vertex, int *elements, in
                                tris += 2;
                        }
                }
+#endif
        }
        R_Shadow_RenderVolume(numverts * 2, tris, shadowelements);
 }