Cycles: add additive AO support through Fast GI settings

Add a Fast GI Method, either Replace for the existing behavior, or Add
to add ambient occlusion like the old world settings.

This replaces the old Ambient Occlusion settings in the world properties.

1 files changed, 9 insertions, 2 deletions

diff --git a/intern/cycles/kernel/kernel_shader.h b/intern/cycles/kernel/kernel_shader.h
index d25191b72cf..22db6d0124e 100644
--- a/intern/cycles/kernel/kernel_shader.h
+++ b/intern/cycles/kernel/kernel_shader.h
@@ -457,19 +457,26 @@ ccl_device float3 shader_bsdf_average_normal(KernelGlobals kg, ccl_private const
   return (is_zero(N)) ? sd->N : normalize(N);
 }
 
-ccl_device float3 shader_bsdf_ao_normal(KernelGlobals kg, ccl_private const ShaderData *sd)
+ccl_device float3 shader_bsdf_ao(KernelGlobals kg,
+                                 ccl_private const ShaderData *sd,
+                                 const float ao_factor,
+                                 ccl_private float3 *N_)
 {
+  float3 eval = zero_float3();
   float3 N = zero_float3();
 
   for (int i = 0; i < sd->num_closure; i++) {
     ccl_private const ShaderClosure *sc = &sd->closure[i];
+
     if (CLOSURE_IS_BSDF_DIFFUSE(sc->type)) {
       ccl_private const DiffuseBsdf *bsdf = (ccl_private const DiffuseBsdf *)sc;
+      eval += sc->weight * ao_factor;
       N += bsdf->N * fabsf(average(sc->weight));
     }
   }
 
-  return (is_zero(N)) ? sd->N : normalize(N);
+  *N_ = (is_zero(N)) ? sd->N : normalize(N);
+  return eval;
 }
 
 #ifdef __SUBSURFACE__