Cycles: merge of cycles-x branch, a major update to the renderer

This includes much improved GPU rendering performance, viewport interactivity,
new shadow catcher, revamped sampling settings, subsurface scattering anisotropy,
new GPU volume sampling, improved PMJ sampling pattern, and more.

Some features have also been removed or changed, breaking backwards compatibility.
Including the removal of the OpenCL backend, for which alternatives are under
development.

Release notes and code docs:
https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Cycles
https://wiki.blender.org/wiki/Source/Render/Cycles

Credits:
* Sergey Sharybin
* Brecht Van Lommel
* Patrick Mours (OptiX backend)
* Christophe Hery (subsurface scattering anisotropy)
* William Leeson (PMJ sampling pattern)
* Alaska (various fixes and tweaks)
* Thomas Dinges (various fixes)

For the full commit history, see the cycles-x branch. This squashes together
all the changes since intermediate changes would often fail building or tests.

Ref T87839, T87837, T87836
Fixes T90734, T89353, T80267, T80267, T77185, T69800

1 files changed, 33 insertions, 48 deletions

diff --git a/intern/cycles/kernel/geom/geom_triangle_intersect.h b/intern/cycles/kernel/geom/geom_triangle_intersect.h
index b0cce274b94..30b77ebd2eb 100644
--- a/intern/cycles/kernel/geom/geom_triangle_intersect.h
+++ b/intern/cycles/kernel/geom/geom_triangle_intersect.h
@@ -20,12 +20,17 @@
  * intersection at the cost of more memory usage.
  */
 
+#pragma once
+
+#include "kernel/kernel_random.h"
+
 CCL_NAMESPACE_BEGIN
 
-ccl_device_inline bool triangle_intersect(KernelGlobals *kg,
+ccl_device_inline bool triangle_intersect(const KernelGlobals *kg,
                                           Intersection *isect,
                                           float3 P,
                                           float3 dir,
+                                          float tmax,
                                           uint visibility,
                                           int object,
                                           int prim_addr)
@@ -41,7 +46,7 @@ ccl_device_inline bool triangle_intersect(KernelGlobals *kg,
   float t, u, v;
   if (ray_triangle_intersect(P,
                              dir,
-                             isect->t,
+                             tmax,
 #if defined(__KERNEL_SSE2__) && defined(__KERNEL_SSE__)
                              ssef_verts,
 #else
@@ -78,7 +83,7 @@ ccl_device_inline bool triangle_intersect(KernelGlobals *kg,
  */
 
 #ifdef __BVH_LOCAL__
-ccl_device_inline bool triangle_intersect_local(KernelGlobals *kg,
+ccl_device_inline bool triangle_intersect_local(const KernelGlobals *kg,
                                                 LocalIntersection *local_isect,
                                                 float3 P,
                                                 float3 dir,
@@ -192,25 +197,20 @@ ccl_device_inline bool triangle_intersect_local(KernelGlobals *kg,
  * http://www.cs.virginia.edu/~gfx/Courses/2003/ImageSynthesis/papers/Acceleration/Fast%20MinimumStorage%20RayTriangle%20Intersection.pdf
  */
 
-ccl_device_inline float3 triangle_refine(KernelGlobals *kg,
+ccl_device_inline float3 triangle_refine(const KernelGlobals *kg,
                                          ShaderData *sd,
-                                         const Intersection *isect,
-                                         const Ray *ray)
+                                         float3 P,
+                                         float3 D,
+                                         float t,
+                                         const int isect_object,
+                                         const int isect_prim)
 {
-  float3 P = ray->P;
-  float3 D = ray->D;
-  float t = isect->t;
-
 #ifdef __INTERSECTION_REFINE__
-  if (isect->object != OBJECT_NONE) {
+  if (isect_object != OBJECT_NONE) {
     if (UNLIKELY(t == 0.0f)) {
       return P;
     }
-#  ifdef __OBJECT_MOTION__
-    Transform tfm = sd->ob_itfm;
-#  else
-    Transform tfm = object_fetch_transform(kg, isect->object, OBJECT_INVERSE_TRANSFORM);
-#  endif
+    const Transform tfm = object_get_inverse_transform(kg, sd);
 
     P = transform_point(&tfm, P);
     D = transform_direction(&tfm, D * t);
@@ -219,7 +219,7 @@ ccl_device_inline float3 triangle_refine(KernelGlobals *kg,
 
   P = P + D * t;
 
-  const uint tri_vindex = kernel_tex_fetch(__prim_tri_index, isect->prim);
+  const uint tri_vindex = kernel_tex_fetch(__prim_tri_index, isect_prim);
   const float4 tri_a = kernel_tex_fetch(__prim_tri_verts, tri_vindex + 0),
                tri_b = kernel_tex_fetch(__prim_tri_verts, tri_vindex + 1),
                tri_c = kernel_tex_fetch(__prim_tri_verts, tri_vindex + 2);
@@ -239,13 +239,8 @@ ccl_device_inline float3 triangle_refine(KernelGlobals *kg,
     P = P + D * rt;
   }
 
-  if (isect->object != OBJECT_NONE) {
-#  ifdef __OBJECT_MOTION__
-    Transform tfm = sd->ob_tfm;
-#  else
-    Transform tfm = object_fetch_transform(kg, isect->object, OBJECT_TRANSFORM);
-#  endif
-
+  if (isect_object != OBJECT_NONE) {
+    const Transform tfm = object_get_transform(kg, sd);
     P = transform_point(&tfm, P);
   }
 
@@ -255,28 +250,23 @@ ccl_device_inline float3 triangle_refine(KernelGlobals *kg,
 #endif
 }
 
-/* Same as above, except that isect->t is assumed to be in object space for
+/* Same as above, except that t is assumed to be in object space for
  * instancing.
  */
-ccl_device_inline float3 triangle_refine_local(KernelGlobals *kg,
+ccl_device_inline float3 triangle_refine_local(const KernelGlobals *kg,
                                                ShaderData *sd,
-                                               const Intersection *isect,
-                                               const Ray *ray)
+                                               float3 P,
+                                               float3 D,
+                                               float t,
+                                               const int isect_object,
+                                               const int isect_prim)
 {
 #ifdef __KERNEL_OPTIX__
-  /* isect->t is always in world space with OptiX. */
-  return triangle_refine(kg, sd, isect, ray);
+  /* t is always in world space with OptiX. */
+  return triangle_refine(kg, sd, P, D, t, isect_object, isect_prim);
 #else
-  float3 P = ray->P;
-  float3 D = ray->D;
-  float t = isect->t;
-
-  if (isect->object != OBJECT_NONE) {
-#  ifdef __OBJECT_MOTION__
-    Transform tfm = sd->ob_itfm;
-#  else
-    Transform tfm = object_fetch_transform(kg, isect->object, OBJECT_INVERSE_TRANSFORM);
-#  endif
+  if (isect_object != OBJECT_NONE) {
+    const Transform tfm = object_get_inverse_transform(kg, sd);
 
     P = transform_point(&tfm, P);
     D = transform_direction(&tfm, D);
@@ -286,7 +276,7 @@ ccl_device_inline float3 triangle_refine_local(KernelGlobals *kg,
   P = P + D * t;
 
 #  ifdef __INTERSECTION_REFINE__
-  const uint tri_vindex = kernel_tex_fetch(__prim_tri_index, isect->prim);
+  const uint tri_vindex = kernel_tex_fetch(__prim_tri_index, isect_prim);
   const float4 tri_a = kernel_tex_fetch(__prim_tri_verts, tri_vindex + 0),
                tri_b = kernel_tex_fetch(__prim_tri_verts, tri_vindex + 1),
                tri_c = kernel_tex_fetch(__prim_tri_verts, tri_vindex + 2);
@@ -307,13 +297,8 @@ ccl_device_inline float3 triangle_refine_local(KernelGlobals *kg,
   }
 #  endif /* __INTERSECTION_REFINE__ */
 
-  if (isect->object != OBJECT_NONE) {
-#  ifdef __OBJECT_MOTION__
-    Transform tfm = sd->ob_tfm;
-#  else
-    Transform tfm = object_fetch_transform(kg, isect->object, OBJECT_TRANSFORM);
-#  endif
-
+  if (isect_object != OBJECT_NONE) {
+    const Transform tfm = object_get_transform(kg, sd);
     P = transform_point(&tfm, P);
   }