R_CompleteLightPoint: more correct sampling

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@10574 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/r_shadow.c b/r_shadow.c
index fa594fdeda3fe6ea44d07d4ec622c88b88778603..3952e23179af146e609b4029e39bd87496c095e1 100644 (file)
--- a/r_shadow.c
+++ b/r_shadow.c
@@ -6017,7 +6017,7 @@ void R_CompleteLightPoint(vec3_t ambientcolor, vec3_t diffusecolor, vec3_t diffu
        if (dynamic)
        {
                int i, numlights, flag;
-               float f, v[3];
+               float f, relativepoint[3], dist, dist2, lightradius2;
                rtlight_t *light;
                dlight_t *dlight;
 
@@ -6034,10 +6034,17 @@ void R_CompleteLightPoint(vec3_t ambientcolor, vec3_t diffusecolor, vec3_t diffu
                                light = &dlight->rtlight;
                                if (!(light->flags & flag))
                                        continue;
-                               Matrix4x4_Transform(&light->matrix_worldtolight, p, v);
-                               f = 1 - VectorLength2(v);
+                               // sample
+                               lightradius2 = light->radius * light->radius;
+                               VectorSubtract(light->shadoworigin, p, relativepoint);
+                               dist2 = VectorLength2(relativepoint);
+                               if (dist2 >= lightradius2)
+                                       continue;
+                               dist = sqrt(dist2) / light->radius;
+                               f = dist < 1 ? (r_shadow_lightintensityscale.value * ((1.0f - dist) * r_shadow_lightattenuationlinearscale.value / (r_shadow_lightattenuationdividebias.value + dist*dist))) : 0;
                                if (f <= 0)
                                        continue;
+                               // todo: add to both ambient and diffuse
                                if (!light->shadow || CL_TraceLine(p, light->shadoworigin, MOVE_NOMONSTERS, NULL, SUPERCONTENTS_SOLID, true, false, NULL, false).fraction == 1)
                                        VectorMA(ambientcolor, f, light->currentcolor, ambientcolor);
                        }
@@ -6047,10 +6054,17 @@ void R_CompleteLightPoint(vec3_t ambientcolor, vec3_t diffusecolor, vec3_t diffu
                for (i = 0;i < r_refdef.scene.numlights;i++)
                {
                        light = r_refdef.scene.lights[i];
-                       Matrix4x4_Transform(&light->matrix_worldtolight, p, v);
-                       f = (1 - VectorLength2(v)) * r_refdef.scene.rtlightstylevalue[light->style];
+                       // sample
+                       lightradius2 = light->radius * light->radius;
+                       VectorSubtract(light->shadoworigin, p, relativepoint);
+                       dist2 = VectorLength2(relativepoint);
+                       if (dist2 >= lightradius2)
+                               continue;
+                       dist = sqrt(dist2) / light->radius;
+                       f = dist < 1 ? (r_shadow_lightintensityscale.value * ((1.0f - dist) * r_shadow_lightattenuationlinearscale.value / (r_shadow_lightattenuationdividebias.value + dist*dist))) : 0;
                        if (f <= 0)
                                continue;
+                       // todo: add to both ambient and diffuse
                        if (!light->shadow || CL_TraceLine(p, light->shadoworigin, MOVE_NOMONSTERS, NULL, SUPERCONTENTS_SOLID, true, false, NULL, false).fraction == 1)
                                VectorMA(ambientcolor, f, light->color, ambientcolor);
                }