DRW: Batch Cache: Add batch request system

This makes it possible for engines to ask for batches and only fill their
data after all engine populate functions have run.
This means that, when creating the batches data we already know all the
batches that are needed for this redraw and the needed data.

This allows for less redundant data preparation and better attrib masking.
Ideally, we should run all viewports populate function before executing
the batch construction but this is not the scope of this patch.

Conversion from the old request method will be progressive and both can
coexist (see uses of mesh_create_pos_and_nor()).

1 files changed, 13 insertions, 0 deletions

diff --git a/source/blender/draw/intern/draw_cache_impl.h b/source/blender/draw/intern/draw_cache_impl.h
index 287b29ff1ba..4581f5c1f1d 100644
--- a/source/blender/draw/intern/draw_cache_impl.h
+++ b/source/blender/draw/intern/draw_cache_impl.h
@@ -124,6 +124,8 @@ void DRW_mesh_weight_state_copy(struct DRW_MeshWeightState *wstate_dst, const st
 bool DRW_mesh_weight_state_compare(const struct DRW_MeshWeightState *a, const struct DRW_MeshWeightState *b);
 
 /* Mesh */
+void DRW_mesh_batch_cache_create_requested(struct Object *ob);
+
 struct GPUBatch **DRW_mesh_batch_cache_get_surface_shaded(
         struct Mesh *me, struct GPUMaterial **gpumat_array, uint gpumat_array_len, bool use_hide,
         char **auto_layer_names, int **auto_layer_is_srgb, int *auto_layer_count);
@@ -213,4 +215,15 @@ struct GPUBatch *DRW_particles_batch_cache_get_edit_inner_points(
 struct GPUBatch *DRW_particles_batch_cache_get_edit_tip_points(
         struct Object *object, struct ParticleSystem *psys, struct PTCacheEdit *edit);
 
+/* Common */
+#define DRW_ADD_FLAG_FROM_VBO_REQUEST(flag, vbo, value) (flag |= DRW_vbo_requested(vbo) ? value : 0)
+#define DRW_ADD_FLAG_FROM_IBO_REQUEST(flag, ibo, value) (flag |= DRW_ibo_requested(ibo) ? value : 0)
+
+struct GPUBatch *DRW_batch_request(struct GPUBatch **batch);
+bool DRW_batch_requested(struct GPUBatch *batch, int prim_type);
+void DRW_ibo_request(struct GPUBatch *batch, struct GPUIndexBuf **ibo);
+bool DRW_ibo_requested(struct GPUIndexBuf *ibo);
+void DRW_vbo_request(struct GPUBatch *batch, struct GPUVertBuf **vbo);
+bool DRW_vbo_requested(struct GPUVertBuf *vbo);
+
 #endif /* __DRAW_CACHE_IMPL_H__ */