Bake-API: reduce memory footprint when baking more than one object (Fix T41092)

Combine all the highpoly pixel arrays into a single array with a lookup
object_id for each of the highpoly objects.

Note: This changes the Bake API, external engines should refer to the
bake_api.c for the latest API.

Many thanks for Sergey Sharybin for the complete review, changes
suggestion and feedback. (you rock!)

Reviewers: sergey

Subscribers: pildanovak, marcclintdion, monio, metalliandy, brecht

Maniphest Tasks: T41092

Differential Revision: https://developer.blender.org/D772

2 files changed, 4 insertions, 5 deletions

diff --git a/source/blender/render/extern/include/RE_bake.h b/source/blender/render/extern/include/RE_bake.h
index ffc1246b878..e8a8986714d 100644
--- a/source/blender/render/extern/include/RE_bake.h
+++ b/source/blender/render/extern/include/RE_bake.h
@@ -50,14 +50,13 @@ typedef struct BakeImages {
 } BakeImages;
 
 typedef struct BakePixel {
-	int primitive_id;
+	int primitive_id, object_id;
 	float uv[2];
 	float du_dx, du_dy;
 	float dv_dx, dv_dy;
 } BakePixel;
 
 typedef struct BakeHighPolyData {
-	struct BakePixel *pixel_array;
 	struct Object *ob;
 	struct ModifierData *tri_mod;
 	struct Mesh *me;
@@ -72,7 +71,7 @@ typedef struct BakeHighPolyData {
 bool RE_bake_has_engine(struct Render *re);
 
 bool RE_bake_engine(
-        struct Render *re, struct Object *object, const BakePixel pixel_array[],
+        struct Render *re, struct Object *object, const int object_id, const BakePixel pixel_array[],
         const size_t num_pixels, const int depth, const ScenePassType pass_type, float result[]);
 
 /* bake.c */
@@ -82,7 +81,7 @@ bool RE_bake_internal(
         const size_t num_pixels, const int depth, const ScenePassType pass_type, float result[]);
 
 bool RE_bake_pixels_populate_from_objects(
-        struct Mesh *me_low, BakePixel pixel_array_from[],
+        struct Mesh *me_low, BakePixel pixel_array_from[], BakePixel pixel_array_to[],
         BakeHighPolyData highpoly[], const int tot_highpoly, const size_t num_pixels, const bool is_custom_cage,
         const float cage_extrusion, float mat_low[4][4], float mat_cage[4][4], struct Mesh *me_cage);
 
diff --git a/source/blender/render/extern/include/RE_engine.h b/source/blender/render/extern/include/RE_engine.h
index 4857c409f08..9d3c74163d5 100644
--- a/source/blender/render/extern/include/RE_engine.h
+++ b/source/blender/render/extern/include/RE_engine.h
@@ -88,7 +88,7 @@ typedef struct RenderEngineType {
 
 	void (*update)(struct RenderEngine *engine, struct Main *bmain, struct Scene *scene);
 	void (*render)(struct RenderEngine *engine, struct Scene *scene);
-	void (*bake)(struct RenderEngine *engine, struct Scene *scene, struct Object *object, const int pass_type, const struct BakePixel *pixel_array, const int num_pixels, const int depth, void *result);
+	void (*bake)(struct RenderEngine *engine, struct Scene *scene, struct Object *object, const int pass_type, const int object_id, const struct BakePixel *pixel_array, const int num_pixels, const int depth, void *result);
 
 	void (*view_update)(struct RenderEngine *engine, const struct bContext *context);
 	void (*view_draw)(struct RenderEngine *engine, const struct bContext *context);