Cycles: More flexible GI Approximation AO distance control

The goal: allow to easily use AO approximation in scenes which combines
both small and large scale objects.

The idea: use per-object AO distance which will allow to override world
settings. Instancer object will "propagate" its AO distance to all its
instances unless the instance defines own distance (this allows to
modify AO distance in the shot files, without requiring to modify props
used in the shots.

Available from the new Fats GI Approximation panel in object properties.

Differential Revision: https://developer.blender.org/D12112

1 files changed, 10 insertions, 0 deletions

diff --git a/intern/cycles/kernel/bvh/bvh_util.h b/intern/cycles/kernel/bvh/bvh_util.h
index 867ea3af8d1..b1faebce957 100644
--- a/intern/cycles/kernel/bvh/bvh_util.h
+++ b/intern/cycles/kernel/bvh/bvh_util.h
@@ -239,4 +239,14 @@ ccl_device_forceinline int intersection_get_shader(KernelGlobals *ccl_restrict k
   return shader & SHADER_MASK;
 }
 
+ccl_device_forceinline int intersection_get_object(KernelGlobals *ccl_restrict kg,
+                                                   const Intersection *ccl_restrict isect)
+{
+  if (isect->object != OBJECT_NONE) {
+    return isect->object;
+  }
+
+  return kernel_tex_fetch(__prim_object, isect->prim);
+}
+
 CCL_NAMESPACE_END