fix focal plane edge case

haosulab · May 20, 2024 · 6b6d61d · 6b6d61d
1 parent 1e3233d
commit 6b6d61d
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/vulkan_shader/rt/camera.rgen b/vulkan_shader/rt/camera.rgen
@@ -73,6 +73,11 @@ void main() {
     vec3 csFocusOrigin = csNear.xyz + vec3(ax, ay, 0.0);
     vec3 csFocusDir = csFocusPoint - csFocusOrigin;
 
+    // avoid shooting rays backwards
+    if (csFocusDir.z != 0) {
+      csFocusDir /= -csFocusDir.z;
+    }
+
     vec4 origin = cameraBuffer.viewMatrixInverse * vec4(csFocusOrigin, 1.0);
     vec4 direction = cameraBuffer.viewMatrixInverse * vec4(csFocusDir, 0.0);