[Bf-blender-cvs] [58a810e6403] blender2.8: Draw Manager: Add support for instance Batch.

[Clément Foucault]

Commit: 58a810e64033488020d9a7417e0e50987e870546
Author: Clément Foucault
Date:   Tue May 16 20:27:14 2017 +0200
Branches: blender2.8
https://developer.blender.org/rB58a810e64033488020d9a7417e0e50987e870546

Draw Manager: Add support for instance Batch.

Idea is to specify a batch as source of vbo instance attrib.

===================================================================

M	source/blender/draw/intern/DRW_render.h
M	source/blender/draw/intern/draw_manager.c

===================================================================

diff --git a/source/blender/draw/intern/DRW_render.h b/source/blender/draw/intern/DRW_render.h
index 5a3119494b2..9654087f0d8 100644
--- a/source/blender/draw/intern/DRW_render.h
+++ b/source/blender/draw/intern/DRW_render.h
@@ -258,6 +258,8 @@ typedef void (DRWCallGenerateFn)(
         void (*draw_fn)(DRWShadingGroup *shgroup, struct Batch *geom),
         void *user_data);
 
+void DRW_shgroup_instance_batch(DRWShadingGroup *shgroup, struct Batch *instances);
+
 void DRW_shgroup_free(struct DRWShadingGroup *shgroup);
 void DRW_shgroup_call_add(DRWShadingGroup *shgroup, struct Batch *geom, float (*obmat)[4]);
 void DRW_shgroup_call_object_add(DRWShadingGroup *shgroup, struct Batch *geom, struct Object *ob);
diff --git a/source/blender/draw/intern/draw_manager.c b/source/blender/draw/intern/draw_manager.c
index d74ea4fed94..0c45ce9ec2b 100644
--- a/source/blender/draw/intern/draw_manager.c
+++ b/source/blender/draw/intern/draw_manager.c
@@ -174,7 +174,8 @@ struct DRWInterface {
 	/* UBO */
 	int ubo_bind; /* next ubo binding point */
 	/* Dynamic batch */
-	GLuint instance_vbo;
+	Batch *instance_batch; /* contains instances attributes */
+	GLuint instance_vbo; /* same as instance_batch but generated from DRWCalls */
 	int instance_count;
 	VertexFormat vbo_format;
 };
@@ -571,6 +572,7 @@ static DRWInterface *DRW_interface_create(GPUShader *shader)
 	interface->attribs_count = 0;
 	interface->attribs_stride = 0;
 	interface->instance_vbo = 0;
+	interface->instance_batch = NULL;
 	interface->tex_bind = GPU_max_textures() - 1;
 	interface->ubo_bind = GPU_max_ubo_binds() - 1;
 
@@ -811,6 +813,13 @@ void DRW_shgroup_free(struct DRWShadingGroup *shgroup)
 	BATCH_DISCARD_ALL_SAFE(shgroup->batch_geom);
 }
 
+void DRW_shgroup_instance_batch(DRWShadingGroup *shgroup, struct Batch *instances)
+{
+	BLI_assert(shgroup->type == DRW_SHG_INSTANCE);
+
+	shgroup->interface->instance_batch = instances;
+}
+
 void DRW_shgroup_call_add(DRWShadingGroup *shgroup, Batch *geom, float (*obmat)[4])
 {
 	BLI_assert(geom != NULL);
@@ -1099,6 +1108,18 @@ static void shgroup_dynamic_instance(DRWShadingGroup *shgroup)
 	int instance_ct = interface->instance_count;
 	int buffer_size = 0;
 
+	/* XXX All of this is pretty garbage. Better revisit it later. */
+	if (interface->instance_batch != NULL) {
+		VertexBuffer *vert = interface->instance_batch->verts[0];
+		/* This is double check but we don't want
+		 * VertexBuffer_use() to bind the buffer if it exists. */
+		if (vert->vbo_id == 0) {
+			VertexBuffer_use(vert);
+		}
+		interface->instance_vbo = vert->vbo_id;
+		interface->instance_count = vert->vertex_ct;
+	}
+
 	if (instance_ct == 0) {
 		if (interface->instance_vbo) {
 			glDeleteBuffers(1, &interface->instance_vbo);
@@ -1117,6 +1138,11 @@ static void shgroup_dynamic_instance(DRWShadingGroup *shgroup)
 		}
 	}
 
+	if (interface->instance_batch != NULL) {
+		/* Quit just after attribs where specified */
+		return;
+	}
+
 	/* Gather Data */
 	buffer_size = sizeof(float) * interface->attribs_stride * instance_ct;
 	float *data = MEM_mallocN(buffer_size, "Instance VBO data");