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

2 files changed, 20 insertions, 39 deletions

diff --git a/source/blender/nodes/shader/nodes/node_shader_bsdf_principled.c b/source/blender/nodes/shader/nodes/node_shader_bsdf_principled.c
index f601f3e9fd0..06f4d1f1b79 100644
--- a/source/blender/nodes/shader/nodes/node_shader_bsdf_principled.c
+++ b/source/blender/nodes/shader/nodes/node_shader_bsdf_principled.c
@@ -35,6 +35,8 @@ static bNodeSocketTemplate sh_node_bsdf_principled_in[] = {
      PROP_NONE,
      SOCK_COMPACT},
     {SOCK_RGBA, N_("Subsurface Color"), 0.8f, 0.8f, 0.8f, 1.0f, 0.0f, 1.0f},
+    {SOCK_FLOAT, N_("Subsurface IOR"), 1.4f, 0.0f, 0.0f, 0.0f, 1.01f, 3.8f, PROP_FACTOR},
+    {SOCK_FLOAT, N_("Subsurface Anisotropy"), 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_FACTOR},
     {SOCK_FLOAT, N_("Metallic"), 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_FACTOR},
     {SOCK_FLOAT, N_("Specular"), 0.5f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_FACTOR},
     {SOCK_FLOAT, N_("Specular Tint"), 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_FACTOR},
@@ -74,7 +76,7 @@ static bNodeSocketTemplate sh_node_bsdf_principled_out[] = {
 static void node_shader_init_principled(bNodeTree *UNUSED(ntree), bNode *node)
 {
   node->custom1 = SHD_GLOSSY_GGX;
-  node->custom2 = SHD_SUBSURFACE_BURLEY;
+  node->custom2 = SHD_SUBSURFACE_RANDOM_WALK;
 }
 
 #define socket_not_zero(sock) (in[sock].link || (clamp_f(in[sock].vec[0], 0.0f, 1.0f) > 1e-5f))
@@ -90,41 +92,40 @@ static int node_shader_gpu_bsdf_principled(GPUMaterial *mat,
   GPUNodeLink *sss_scale;
 
   /* Normals */
-  if (!in[20].link) {
-    GPU_link(mat, "world_normals_get", &in[20].link);
+  if (!in[22].link) {
+    GPU_link(mat, "world_normals_get", &in[22].link);
   }
 
   /* Clearcoat Normals */
-  if (!in[21].link) {
-    GPU_link(mat, "world_normals_get", &in[21].link);
+  if (!in[23].link) {
+    GPU_link(mat, "world_normals_get", &in[23].link);
   }
 
 #if 0 /* Not used at the moment. */
   /* Tangents */
-  if (!in[22].link) {
+  if (!in[24].link) {
     GPUNodeLink *orco = GPU_attribute(CD_ORCO, "");
-    GPU_link(mat, "tangent_orco_z", orco, &in[22].link);
+    GPU_link(mat, "tangent_orco_z", orco, &in[24].link);
     GPU_link(mat,
              "node_tangent",
              GPU_builtin(GPU_WORLD_NORMAL),
-             in[22].link,
+             in[24].link,
              GPU_builtin(GPU_OBJECT_MATRIX),
-             &in[22].link);
+             &in[24].link);
   }
 #endif
 
-  bool use_diffuse = socket_not_one(4) && socket_not_one(15);
+  bool use_diffuse = socket_not_one(6) && socket_not_one(17);
   bool use_subsurf = socket_not_zero(1) && use_diffuse && node->sss_id > 0;
-  bool use_refract = socket_not_one(4) && socket_not_zero(15);
-  bool use_clear = socket_not_zero(12);
+  bool use_refract = socket_not_one(6) && socket_not_zero(17);
+  bool use_clear = socket_not_zero(14);
 
   /* SSS Profile */
   if (use_subsurf) {
-    static short profile = SHD_SUBSURFACE_BURLEY;
     bNodeSocket *socket = BLI_findlink(&node->original->inputs, 2);
     bNodeSocketValueRGBA *socket_data = socket->default_value;
     /* For some reason it seems that the socket value is in ARGB format. */
-    GPU_material_sss_profile_create(mat, &socket_data->value[1], &profile, NULL);
+    GPU_material_sss_profile_create(mat, &socket_data->value[1]);
   }
 
   if (in[2].link) {
diff --git a/source/blender/nodes/shader/nodes/node_shader_subsurface_scattering.c b/source/blender/nodes/shader/nodes/node_shader_subsurface_scattering.c
index 4b91bcbd11c..e917858e0f2 100644
--- a/source/blender/nodes/shader/nodes/node_shader_subsurface_scattering.c
+++ b/source/blender/nodes/shader/nodes/node_shader_subsurface_scattering.c
@@ -25,8 +25,8 @@ static bNodeSocketTemplate sh_node_subsurface_scattering_in[] = {
     {SOCK_RGBA, N_("Color"), 0.8f, 0.8f, 0.8f, 1.0f, 0.0f, 1.0f},
     {SOCK_FLOAT, N_("Scale"), 1.0, 0.0f, 0.0f, 0.0f, 0.0f, 1000.0f},
     {SOCK_VECTOR, N_("Radius"), 1.0f, 0.2f, 0.1f, 0.0f, 0.0f, 100.0f, PROP_NONE, SOCK_COMPACT},
-    {SOCK_FLOAT, N_("Sharpness"), 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_FACTOR},
-    {SOCK_FLOAT, N_("Texture Blur"), 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_FACTOR},
+    {SOCK_FLOAT, N_("IOR"), 1.4f, 0.0f, 0.0f, 0.0f, 1.01f, 3.8f, PROP_FACTOR},
+    {SOCK_FLOAT, N_("Anisotropy"), 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, PROP_FACTOR},
     {SOCK_VECTOR, N_("Normal"), 0.0f, 0.0f, 0.0f, 1.0f, -1.0f, 1.0f, PROP_NONE, SOCK_HIDE_VALUE},
     {-1, ""},
 };
@@ -38,7 +38,8 @@ static bNodeSocketTemplate sh_node_subsurface_scattering_out[] = {
 
 static void node_shader_init_subsurface_scattering(bNodeTree *UNUSED(ntree), bNode *node)
 {
-  node->custom1 = SHD_SUBSURFACE_BURLEY;
+  node->custom1 = SHD_SUBSURFACE_RANDOM_WALK;
+  node->custom2 = true;
 }
 
 static int node_shader_gpu_subsurface_scattering(GPUMaterial *mat,
@@ -54,11 +55,8 @@ static int node_shader_gpu_subsurface_scattering(GPUMaterial *mat,
   if (node->sss_id > 0) {
     bNodeSocket *socket = BLI_findlink(&node->original->inputs, 2);
     bNodeSocketValueRGBA *socket_data = socket->default_value;
-    bNodeSocket *socket_sharp = BLI_findlink(&node->original->inputs, 3);
-    bNodeSocketValueFloat *socket_data_sharp = socket_sharp->default_value;
     /* For some reason it seems that the socket value is in ARGB format. */
-    GPU_material_sss_profile_create(
-        mat, &socket_data->value[1], &node->original->custom1, &socket_data_sharp->value);
+    GPU_material_sss_profile_create(mat, &socket_data->value[1]);
 
     /* sss_id is 0 only the node is not connected to any output.
      * In this case flagging the material would trigger a bug (see T68736). */
@@ -69,23 +67,6 @@ static int node_shader_gpu_subsurface_scattering(GPUMaterial *mat,
       mat, node, "node_subsurface_scattering", in, out, GPU_constant(&node->sss_id));
 }
 
-static void node_shader_update_subsurface_scattering(bNodeTree *UNUSED(ntree), bNode *node)
-{
-  bNodeSocket *sock;
-  int falloff = node->custom1;
-
-  for (sock = node->inputs.first; sock; sock = sock->next) {
-    if (STREQ(sock->name, "Sharpness")) {
-      if (falloff == SHD_SUBSURFACE_CUBIC) {
-        sock->flag &= ~SOCK_UNAVAIL;
-      }
-      else {
-        sock->flag |= SOCK_UNAVAIL;
-      }
-    }
-  }
-}
-
 /* node type definition */
 void register_node_type_sh_subsurface_scattering(void)
 {
@@ -99,7 +80,6 @@ void register_node_type_sh_subsurface_scattering(void)
   node_type_init(&ntype, node_shader_init_subsurface_scattering);
   node_type_storage(&ntype, "", NULL, NULL);
   node_type_gpu(&ntype, node_shader_gpu_subsurface_scattering);
-  node_type_update(&ntype, node_shader_update_subsurface_scattering);
 
   nodeRegisterType(&ntype);
 }