EEVEE: ScreenSpaceReflections: Avoid outputing NaNs

This happens when the normal is too much deformed to give valid
reflection even after ensure_valid_reflection.

Cycles seems to not handle this case either so we just discard the
rays.

1 files changed, 7 insertions, 0 deletions

diff --git a/source/blender/draw/engines/eevee/shaders/effect_reflection_trace_frag.glsl b/source/blender/draw/engines/eevee/shaders/effect_reflection_trace_frag.glsl
index b88a106e897..b1f17cb7b07 100644
--- a/source/blender/draw/engines/eevee/shaders/effect_reflection_trace_frag.glsl
+++ b/source/blender/draw/engines/eevee/shaders/effect_reflection_trace_frag.glsl
@@ -113,6 +113,13 @@ void main()
   vec3 vH = sample_ggx(rand.xzw, alpha, vV, vN, vT, vB, pdf);
   vec3 vR = reflect(-vV, vH);
 
+  if (isnan(pdf)) {
+    /* Seems that somethings went wrong.
+     * This only happens on extreme cases where the normal deformed too much to have any valid
+     * reflections. */
+    return;
+  }
+
   if (data.is_planar) {
     vec3 view_plane_normal = transform_direction(ViewMatrix, planars_data[planar_id].pl_normal);
     /* For planar reflections, we trace inside the reflected view. */