Fix #29723: wrong IOR for raytraced refraction after reflection inside mesh,

patch by Juha Maki-Kanto.

diff --git a/source/blender/render/intern/source/rayshade.c b/source/blender/render/intern/source/rayshade.c
index 42ad5fd15e567795b34b81aa2a27c8e8bf4317a7..f9ffc2532eb8d841139eefe849052204cbcf4c9d 100644 (file)
--- a/source/blender/render/intern/source/rayshade.c
+++ b/source/blender/render/intern/source/rayshade.c
@@ -780,7 +780,10 @@ static void traceray(ShadeInput *origshi, ShadeResult *origshr, short depth, con
                                tracol[3]= col[3];      // we pass on and accumulate alpha
                                
                                if((shi.mat->mode & MA_TRANSP) && (shi.mat->mode & MA_RAYTRANSP)) {
-                                       if(traflag & RAY_INSIDE) {
+                                       /* don't overwrite traflag, it's value is used in mirror reflection */
+                                       int new_traflag = traflag;
+                                       
+                                       if(new_traflag & RAY_INSIDE) {
                                                /* inside the material, so use inverse normal */
                                                float norm[3];
                                                norm[0]= - shi.vn[0];
@@ -789,7 +792,7 @@ static void traceray(ShadeInput *origshi, ShadeResult *origshr, short depth, con
 
                                                if (refraction(refract, norm, shi.view, shi.ang)) {
                                                        /* ray comes out from the material into air */
-                                                       traflag &= ~RAY_INSIDE;
+                                                       new_traflag &= ~RAY_INSIDE;
                                                }
                                                else {
                                                        /* total internal reflection (ray stays inside the material) */
@@ -799,14 +802,14 @@ static void traceray(ShadeInput *origshi, ShadeResult *origshr, short depth, con
                                        else {
                                                if (refraction(refract, shi.vn, shi.view, shi.ang)) {
                                                        /* ray goes in to the material from air */
-                                                       traflag |= RAY_INSIDE;
+                                                       new_traflag |= RAY_INSIDE;
                                                }
                                                else {
                                                        /* total external reflection (ray doesn't enter the material) */
                                                        reflection(refract, shi.vn, shi.view, shi.vn);
                                                }
                                        }
-                                       traceray(origshi, origshr, depth-1, shi.co, refract, tracol, shi.obi, shi.vlr, traflag);
+                                       traceray(origshi, origshr, depth-1, shi.co, refract, tracol, shi.obi, shi.vlr, new_traflag);
                                }
                                else
                                        traceray(origshi, origshr, depth-1, shi.co, shi.view, tracol, shi.obi, shi.vlr, 0);
@@ -840,7 +843,7 @@ static void traceray(ShadeInput *origshi, ShadeResult *origshr, short depth, con
                                float ref[3];
                                
                                reflection_simple(ref, shi.vn, shi.view);
-                               traceray(origshi, origshr, depth-1, shi.co, ref, mircol, shi.obi, shi.vlr, 0);
+                               traceray(origshi, origshr, depth-1, shi.co, ref, mircol, shi.obi, shi.vlr, traflag);
                        
                                f1= 1.0f-f;