Bake API - bpy.ops.object.bake()

New operator that can calls a bake function to the current render engine when available. This commit provides no feature for the users, but allows external engines to be accessed by the operator and be integrated with the baking api.

The API itself is simple. Blender sends a populated array of BakePixels to the renderer, and gets back an array of floats with the result.

The Blender Internal (and multires) system is still running independent, but we eventually will pipe it through the API as well. Cycles baking will come next as a separated commit

Python Operator:
----------------
The operator can be called with some arguments, or a user interface can be created for it. In that case the arguments can be ommited and the interface can expose the settings from bpy.context.scene.render.bake

bpy.ops.object.bake(type='COMBINED', filepath="", width=512, height=512, margin=16, use_selected_to_active=False, cage_extrusion=0, cage="", normal_space='TANGENT', normal_r='POS_X', normal_g='POS_Y', normal_b='POS_Z', save_mode='INTERNAL', use_clear=False, use_split_materials=False, use_automatic_name=False)
Note: external save mode is currently disabled.

Supported Features:
------------------
 * Margin - Baked result is extended this many pixels beyond the border of each UV "island," to soften seams in the texture.

 * Selected to Active - bake shading on the surface of selected object to the active object. The rays are cast from the lowpoly object inwards towards the highpoly object. If the highpoly object is not entirely involved by the lowpoly object, you can tweak the rays start point with Cage Extrusion. For even more control of the cage you can use a Cage object.

 * Cage Extrusion - distance to use for the inward ray cast when using selected to active

 * Custom Cage - object to use as cage (instead of the lowpoly object).

 * Normal swizzle - change the axis that gets mapped to RGB

 * Normal space - save as tangent or object normal spaces

Supported Passes:
-----------------
Any pass that is supported by Blender renderlayer system. Though it's up to the external engine to provide a valid enum with its supported passes. Normal passes get a special treatment since we post-process them to converted and "swizzled"

Development Notes for External Engines:
---------------------------------------
(read them in bake_api.c)

* For a complete implementation example look at the Cycles Bake commit (next).

Review: D421
Reviewed by: Campbell Barton, Brecht van Lommel, Sergey Sharybin, Thomas Dinge

Normal map pipeline "consulting" by Andy Davies (metalliandy)
Original design by Brecht van Lommel.

The entire commit history can be found on the branch: bake-cycles

1 files changed, 133 insertions, 38 deletions

diff --git a/source/blender/makesrna/intern/rna_render.c b/source/blender/makesrna/intern/rna_render.c
index 1ec11c280cb..16cc82bbca1 100644
--- a/source/blender/makesrna/intern/rna_render.c
+++ b/source/blender/makesrna/intern/rna_render.c
@@ -38,7 +38,41 @@
 
 #include "RE_engine.h"
 #include "RE_pipeline.h"
+#include "RE_engine.h"
+
 
+EnumPropertyItem render_pass_type_items[] = {
+	{SCE_PASS_COMBINED, "COMBINED", 0, "Combined", ""},
+	{SCE_PASS_Z, "Z", 0, "Z", ""},
+	{SCE_PASS_RGBA, "COLOR", 0, "Color", ""},
+	{SCE_PASS_DIFFUSE, "DIFFUSE", 0, "Diffuse", ""},
+	{SCE_PASS_SPEC, "SPECULAR", 0, "Specular", ""},
+	{SCE_PASS_SHADOW, "SHADOW", 0, "Shadow", ""},
+	{SCE_PASS_AO, "AO", 0, "AO", ""},
+	{SCE_PASS_REFLECT, "REFLECTION", 0, "Reflection", ""},
+	{SCE_PASS_NORMAL, "NORMAL", 0, "Normal", ""},
+	{SCE_PASS_VECTOR, "VECTOR", 0, "Vector", ""},
+	{SCE_PASS_REFRACT, "REFRACTION", 0, "Refraction", ""},
+	{SCE_PASS_INDEXOB, "OBJECT_INDEX", 0, "Object Index", ""},
+	{SCE_PASS_UV, "UV", 0, "UV", ""},
+	{SCE_PASS_MIST, "MIST", 0, "Mist", ""},
+	{SCE_PASS_EMIT, "EMIT", 0, "Emit", ""},
+	{SCE_PASS_ENVIRONMENT, "ENVIRONMENT", 0, "Environment", ""},
+	{SCE_PASS_INDEXMA, "MATERIAL_INDEX", 0, "Material Index", ""},
+	{SCE_PASS_DIFFUSE_DIRECT, "DIFFUSE_DIRECT", 0, "Diffuse Direct", ""},
+	{SCE_PASS_DIFFUSE_INDIRECT, "DIFFUSE_INDIRECT", 0, "Diffuse Indirect", ""},
+	{SCE_PASS_DIFFUSE_COLOR, "DIFFUSE_COLOR", 0, "Diffuse Color", ""},
+	{SCE_PASS_GLOSSY_DIRECT, "GLOSSY_DIRECT", 0, "Glossy Direct", ""},
+	{SCE_PASS_GLOSSY_INDIRECT, "GLOSSY_INDIRECT", 0, "Glossy Indirect", ""},
+	{SCE_PASS_GLOSSY_COLOR, "GLOSSY_COLOR", 0, "Glossy Color", ""},
+	{SCE_PASS_TRANSM_DIRECT, "TRANSMISSION_DIRECT", 0, "Transmission Direct", ""},
+	{SCE_PASS_TRANSM_INDIRECT, "TRANSMISSION_INDIRECT", 0, "Transmission Indirect", ""},
+	{SCE_PASS_TRANSM_COLOR, "TRANSMISSION_COLOR", 0, "Transmission Color", ""},
+	{SCE_PASS_SUBSURFACE_DIRECT, "SUBSURFACE_DIRECT", 0, "Subsurface Direct", ""},
+	{SCE_PASS_SUBSURFACE_INDIRECT, "SUBSURFACE_INDIRECT", 0, "Subsurface Indirect", ""},
+	{SCE_PASS_SUBSURFACE_COLOR, "SUBSURFACE_COLOR", 0, "Subsurface Color", ""},
+	{0, NULL, 0, NULL, NULL}
+};
 
 #ifdef RNA_RUNTIME
 
@@ -117,6 +151,30 @@ static void engine_render(RenderEngine *engine, struct Scene *scene)
 	RNA_parameter_list_free(&list);
 }
 
+static void engine_bake(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)
+{
+	extern FunctionRNA rna_RenderEngine_bake_func;
+	PointerRNA ptr;
+	ParameterList list;
+	FunctionRNA *func;
+
+	RNA_pointer_create(NULL, engine->type->ext.srna, engine, &ptr);
+	func = &rna_RenderEngine_bake_func;
+
+	RNA_parameter_list_create(&list, &ptr, func);
+	RNA_parameter_set_lookup(&list, "scene", &scene);
+	RNA_parameter_set_lookup(&list, "object", &object);
+	RNA_parameter_set_lookup(&list, "pass_type", &pass_type);
+	RNA_parameter_set_lookup(&list, "pixel_array", &pixel_array);
+	RNA_parameter_set_lookup(&list, "num_pixels", &num_pixels);
+	RNA_parameter_set_lookup(&list, "depth", &depth);
+	RNA_parameter_set_lookup(&list, "result", &result);
+	engine->type->ext.call(NULL, &ptr, func, &list);
+
+	RNA_parameter_list_free(&list);
+}
+
 static void engine_view_update(RenderEngine *engine, const struct bContext *context)
 {
 	extern FunctionRNA rna_RenderEngine_view_update_func;
@@ -189,7 +247,7 @@ static StructRNA *rna_RenderEngine_register(Main *bmain, ReportList *reports, vo
 	RenderEngineType *et, dummyet = {NULL};
 	RenderEngine dummyengine = {NULL};
 	PointerRNA dummyptr;
-	int have_function[5];
+	int have_function[6];
 
 	/* setup dummy engine & engine type to store static properties in */
 	dummyengine.type = &dummyet;
@@ -226,9 +284,10 @@ static StructRNA *rna_RenderEngine_register(Main *bmain, ReportList *reports, vo
 
 	et->update = (have_function[0]) ? engine_update : NULL;
 	et->render = (have_function[1]) ? engine_render : NULL;
-	et->view_update = (have_function[2]) ? engine_view_update : NULL;
-	et->view_draw = (have_function[3]) ? engine_view_draw : NULL;
-	et->update_script_node = (have_function[4]) ? engine_update_script_node : NULL;
+	et->bake = (have_function[2]) ? engine_bake : NULL;
+	et->view_update = (have_function[3]) ? engine_view_update : NULL;
+	et->view_draw = (have_function[4]) ? engine_view_draw : NULL;
+	et->update_script_node = (have_function[5]) ? engine_update_script_node : NULL;
 
 	BLI_addtail(&R_engines, et);
 
@@ -317,6 +376,12 @@ void rna_RenderPass_rect_set(PointerRNA *ptr, const float *values)
 	memcpy(rpass->rect, values, sizeof(float) * rpass->rectx * rpass->recty * rpass->channels);
 }
 
+static PointerRNA rna_BakePixel_next_get(PointerRNA *ptr)
+{
+	BakePixel *bp = ptr->data;
+	return rna_pointer_inherit_refine(ptr, &RNA_BakePixel, bp + 1);
+}
+
 #else /* RNA_RUNTIME */
 
 static void rna_def_render_engine(BlenderRNA *brna)
@@ -344,6 +409,25 @@ static void rna_def_render_engine(BlenderRNA *brna)
 	RNA_def_function_flag(func, FUNC_REGISTER_OPTIONAL | FUNC_ALLOW_WRITE);
 	RNA_def_pointer(func, "scene", "Scene", "", "");
 
+	func = RNA_def_function(srna, "bake", NULL);
+	RNA_def_function_ui_description(func, "Bake passes");
+	RNA_def_function_flag(func, FUNC_REGISTER_OPTIONAL | FUNC_ALLOW_WRITE);
+	prop = RNA_def_pointer(func, "scene", "Scene", "", "");
+	RNA_def_property_flag(prop, PROP_REQUIRED);
+	prop = RNA_def_pointer(func, "object", "Object", "", "");
+	RNA_def_property_flag(prop, PROP_REQUIRED);
+	prop = RNA_def_enum(func, "pass_type", render_pass_type_items, 0, "Pass", "Pass to bake");
+	RNA_def_property_flag(prop, PROP_REQUIRED);
+	prop = RNA_def_pointer(func, "pixel_array", "BakePixel", "", "");
+	RNA_def_property_flag(prop, PROP_REQUIRED);
+	prop = RNA_def_int(func, "num_pixels", 0, 0, INT_MAX, "Number of Pixels", "Size of the baking batch", 0, INT_MAX);
+	RNA_def_property_flag(prop, PROP_REQUIRED);
+	prop = RNA_def_int(func, "depth", 0, 0, INT_MAX, "Pixels depth", "Number of channels", 1, INT_MAX);
+	RNA_def_property_flag(prop, PROP_REQUIRED);
+	/* TODO, see how array size of 0 works, this shouldnt be used */
+	prop = RNA_def_pointer(func, "result", "AnyType", "", "");
+	RNA_def_property_flag(prop, PROP_REQUIRED);
+
 	/* viewport render callbacks */
 	func = RNA_def_function(srna, "view_update", NULL);
 	RNA_def_function_ui_description(func, "Update on data changes for viewport render");
@@ -588,39 +672,6 @@ static void rna_def_render_pass(BlenderRNA *brna)
 	StructRNA *srna;
 	PropertyRNA *prop;
 
-	static EnumPropertyItem pass_type_items[] = {
-		{SCE_PASS_COMBINED, "COMBINED", 0, "Combined", ""},
-		{SCE_PASS_Z, "Z", 0, "Z", ""},
-		{SCE_PASS_RGBA, "COLOR", 0, "Color", ""},
-		{SCE_PASS_DIFFUSE, "DIFFUSE", 0, "Diffuse", ""},
-		{SCE_PASS_SPEC, "SPECULAR", 0, "Specular", ""},
-		{SCE_PASS_SHADOW, "SHADOW", 0, "Shadow", ""},
-		{SCE_PASS_AO, "AO", 0, "AO", ""},
-		{SCE_PASS_REFLECT, "REFLECTION", 0, "Reflection", ""},
-		{SCE_PASS_NORMAL, "NORMAL", 0, "Normal", ""},
-		{SCE_PASS_VECTOR, "VECTOR", 0, "Vector", ""},
-		{SCE_PASS_REFRACT, "REFRACTION", 0, "Refraction", ""},
-		{SCE_PASS_INDEXOB, "OBJECT_INDEX", 0, "Object Index", ""},
-		{SCE_PASS_UV, "UV", 0, "UV", ""},
-		{SCE_PASS_MIST, "MIST", 0, "Mist", ""},
-		{SCE_PASS_EMIT, "EMIT", 0, "Emit", ""},
-		{SCE_PASS_ENVIRONMENT, "ENVIRONMENT", 0, "Environment", ""},
-		{SCE_PASS_INDEXMA, "MATERIAL_INDEX", 0, "Material Index", ""},
-		{SCE_PASS_DIFFUSE_DIRECT, "DIFFUSE_DIRECT", 0, "Diffuse Direct", ""},
-		{SCE_PASS_DIFFUSE_INDIRECT, "DIFFUSE_INDIRECT", 0, "Diffuse Indirect", ""},
-		{SCE_PASS_DIFFUSE_COLOR, "DIFFUSE_COLOR", 0, "Diffuse Color", ""},
-		{SCE_PASS_GLOSSY_DIRECT, "GLOSSY_DIRECT", 0, "Glossy Direct", ""},
-		{SCE_PASS_GLOSSY_INDIRECT, "GLOSSY_INDIRECT", 0, "Glossy Indirect", ""},
-		{SCE_PASS_GLOSSY_COLOR, "GLOSSY_COLOR", 0, "Glossy Color", ""},
-		{SCE_PASS_TRANSM_DIRECT, "TRANSMISSION_DIRECT", 0, "Transmission Direct", ""},
-		{SCE_PASS_TRANSM_INDIRECT, "TRANSMISSION_INDIRECT", 0, "Transmission Indirect", ""},
-		{SCE_PASS_TRANSM_COLOR, "TRANSMISSION_COLOR", 0, "Transmission Color", ""},
-		{SCE_PASS_SUBSURFACE_DIRECT, "SUBSURFACE_DIRECT", 0, "Subsurface Direct", ""},
-		{SCE_PASS_SUBSURFACE_INDIRECT, "SUBSURFACE_INDIRECT", 0, "Subsurface Indirect", ""},
-		{SCE_PASS_SUBSURFACE_COLOR, "SUBSURFACE_COLOR", 0, "Subsurface Color", ""},
-		{0, NULL, 0, NULL, NULL}
-	};
-	
 	srna = RNA_def_struct(brna, "RenderPass", NULL);
 	RNA_def_struct_ui_text(srna, "Render Pass", "");
 
@@ -641,7 +692,7 @@ static void rna_def_render_pass(BlenderRNA *brna)
 
 	prop = RNA_def_property(srna, "type", PROP_ENUM, PROP_NONE);
 	RNA_def_property_enum_sdna(prop, NULL, "passtype");
-	RNA_def_property_enum_items(prop, pass_type_items);
+	RNA_def_property_enum_items(prop, render_pass_type_items);
 	RNA_def_property_clear_flag(prop, PROP_EDITABLE);
 
 	prop = RNA_def_property(srna, "rect", PROP_FLOAT, PROP_NONE);
@@ -653,12 +704,56 @@ static void rna_def_render_pass(BlenderRNA *brna)
 	RNA_define_verify_sdna(1);
 }
 
+static void rna_def_render_bake_pixel(BlenderRNA *brna)
+{
+	StructRNA *srna;
+	PropertyRNA *prop;
+
+	srna = RNA_def_struct(brna, "BakePixel", NULL);
+	RNA_def_struct_ui_text(srna, "Bake Pixel", "");
+
+	RNA_define_verify_sdna(0);
+
+	prop = RNA_def_property(srna, "primitive_id", PROP_INT, PROP_NONE);
+	RNA_def_property_int_sdna(prop, NULL, "primitive_id");
+	RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+
+	prop = RNA_def_property(srna, "uv", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_array(prop, 2);
+	RNA_def_property_float_sdna(prop, NULL, "uv");
+	RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+
+	prop = RNA_def_property(srna, "du_dx", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_float_sdna(prop, NULL, "du_dx");
+	RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+
+	prop = RNA_def_property(srna, "du_dy", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_float_sdna(prop, NULL, "du_dy");
+	RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+
+	prop = RNA_def_property(srna, "dv_dx", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_float_sdna(prop, NULL, "dv_dx");
+	RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+
+	prop = RNA_def_property(srna, "dv_dy", PROP_FLOAT, PROP_NONE);
+	RNA_def_property_float_sdna(prop, NULL, "dv_dy");
+	RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+
+	prop = RNA_def_property(srna, "next", PROP_POINTER, PROP_NONE);
+	RNA_def_property_struct_type(prop, "BakePixel");
+	RNA_def_property_pointer_funcs(prop, "rna_BakePixel_next_get", NULL, NULL, NULL);
+	RNA_def_property_clear_flag(prop, PROP_EDITABLE);
+
+	RNA_define_verify_sdna(1);
+}
+
 void RNA_def_render(BlenderRNA *brna)
 {
 	rna_def_render_engine(brna);
 	rna_def_render_result(brna);
 	rna_def_render_layer(brna);
 	rna_def_render_pass(brna);
+	rna_def_render_bake_pixel(brna);
 }
 
 #endif /* RNA_RUNTIME */