Cycles: code refactor to bake using regular render session and tiles

There should be no user visible change from this, except that tile size
now affects performance. The goal here is to simplify bake denoising in
D3099, letting it reuse more denoising tiles and pass code.

A lot of code is now shared with regular rendering, with the two main
differences being that we read some render result passes from the bake API
when starting to render a tile, and call the bake kernel instead of the
path trace kernel.

With this kind of design where Cycles asks for tiles from the bake API,
it should eventually be easier to reduce memory usage, show tiles as
they are baked, or bake multiple passes at once, though there's still
quite some work needed for that.

Reviewers: #cycles

Subscribers: monio, wmatyjewicz, lukasstockner97, michaelknubben

Differential Revision: https://developer.blender.org/D3108

1 files changed, 17 insertions, 0 deletions

diff --git a/intern/cycles/kernel/kernel_types.h b/intern/cycles/kernel/kernel_types.h
index a1f8c35348d..304835a1685 100644
--- a/intern/cycles/kernel/kernel_types.h
+++ b/intern/cycles/kernel/kernel_types.h
@@ -395,6 +395,10 @@ typedef enum PassType {
   PASS_VOLUME_INDIRECT,
   /* No Scatter color since it's tricky to define what it would even mean. */
   PASS_CATEGORY_LIGHT_END = 63,
+
+  PASS_BAKE_PRIMITIVE,
+  PASS_BAKE_DIFFERENTIAL,
+  PASS_CATEGORY_BAKE_END = 95
 } PassType;
 
 #define PASS_ANY (~0)
@@ -1248,6 +1252,10 @@ typedef struct KernelFilm {
   float4 xyz_to_b;
   float4 rgb_to_y;
 
+  int pass_bake_primitive;
+  int pass_bake_differential;
+  int pad;
+
 #ifdef __KERNEL_DEBUG__
   int pass_bvh_traversed_nodes;
   int pass_bvh_traversed_instances;
@@ -1427,6 +1435,14 @@ typedef struct KernelTables {
 } KernelTables;
 static_assert_align(KernelTables, 16);
 
+typedef struct KernelBake {
+  int object_index;
+  int tri_offset;
+  int type;
+  int pass_filter;
+} KernelBake;
+static_assert_align(KernelBake, 16);
+
 typedef struct KernelData {
   KernelCamera cam;
   KernelFilm film;
@@ -1435,6 +1451,7 @@ typedef struct KernelData {
   KernelBVH bvh;
   KernelCurves curve;
   KernelTables tables;
+  KernelBake bake;
 } KernelData;
 static_assert_align(KernelData, 16);