Vertex and attribute compression to reduce the size of the vertex format.

This allows Godot to automatically compress meshes to save a lot of bandwidth.

In general, this requires no interaction from the user and should result in
no noticable quality loss.

This scheme is not backwards compatible, so we have provided an upgrade
mechanism, and a mesh versioning mechanism.

Existing meshes can still be used as a result, but users can get a
performance boost by reimporting assets.

1 files changed, 22 insertions, 5 deletions

diff --git a/servers/rendering/renderer_rd/storage_rd/mesh_storage.h b/servers/rendering/renderer_rd/storage_rd/mesh_storage.h
index 1e1db9c47d..f03334baac 100644
--- a/servers/rendering/renderer_rd/storage_rd/mesh_storage.h
+++ b/servers/rendering/renderer_rd/storage_rd/mesh_storage.h
@@ -73,7 +73,7 @@ private:
 	struct Mesh {
 		struct Surface {
 			RS::PrimitiveType primitive = RS::PRIMITIVE_POINTS;
-			uint32_t format = 0;
+			uint64_t format = 0;
 
 			RID vertex_buffer;
 			RID attribute_buffer;
@@ -90,7 +90,7 @@ private:
 			// cache-efficient structure.
 
 			struct Version {
-				uint32_t input_mask = 0;
+				uint64_t input_mask = 0;
 				uint32_t current_buffer = 0;
 				uint32_t previous_buffer = 0;
 				bool input_motion_vectors = false;
@@ -120,6 +120,8 @@ private:
 
 			Vector<AABB> bone_aabbs;
 
+			Vector4 uv_scale;
+
 			RID blend_shape_buffer;
 
 			RID material;
@@ -190,7 +192,7 @@ private:
 				weight_update_list(this), array_update_list(this) {}
 	};
 
-	void _mesh_surface_generate_version_for_input_mask(Mesh::Surface::Version &v, Mesh::Surface *s, uint32_t p_input_mask, bool p_input_motion_vectors, MeshInstance::Surface *mis = nullptr, uint32_t p_current_buffer = 0, uint32_t p_previous_buffer = 0);
+	void _mesh_surface_generate_version_for_input_mask(Mesh::Surface::Version &v, Mesh::Surface *s, uint64_t p_input_mask, bool p_input_motion_vectors, MeshInstance::Surface *mis = nullptr, uint32_t p_current_buffer = 0, uint32_t p_previous_buffer = 0);
 
 	void _mesh_instance_clear(MeshInstance *mi);
 	void _mesh_instance_add_surface(MeshInstance *mi, Mesh *mesh, uint32_t p_surface);
@@ -265,7 +267,7 @@ private:
 
 			uint32_t blend_shape_count;
 			uint32_t normalized_blend_shapes;
-			uint32_t pad0;
+			uint32_t normal_tangent_stride;
 			uint32_t pad1;
 			float skeleton_transform_x[2];
 			float skeleton_transform_y[2];
@@ -422,6 +424,21 @@ public:
 		return s->index_count ? s->index_count : s->vertex_count;
 	}
 
+	_FORCE_INLINE_ AABB mesh_surface_get_aabb(void *p_surface) {
+		Mesh::Surface *s = reinterpret_cast<Mesh::Surface *>(p_surface);
+		return s->aabb;
+	}
+
+	_FORCE_INLINE_ uint64_t mesh_surface_get_format(void *p_surface) {
+		Mesh::Surface *s = reinterpret_cast<Mesh::Surface *>(p_surface);
+		return s->format;
+	}
+
+	_FORCE_INLINE_ Vector4 mesh_surface_get_uv_scale(void *p_surface) {
+		Mesh::Surface *s = reinterpret_cast<Mesh::Surface *>(p_surface);
+		return s->uv_scale;
+	}
+
 	_FORCE_INLINE_ uint32_t mesh_surface_get_lod(void *p_surface, float p_model_scale, float p_distance_threshold, float p_mesh_lod_threshold, uint32_t &r_index_count) const {
 		Mesh::Surface *s = reinterpret_cast<Mesh::Surface *>(p_surface);
 
@@ -484,7 +501,7 @@ public:
 		s->version_lock.unlock();
 	}
 
-	_FORCE_INLINE_ void mesh_instance_surface_get_vertex_arrays_and_format(RID p_mesh_instance, uint32_t p_surface_index, uint32_t p_input_mask, bool p_input_motion_vectors, RID &r_vertex_array_rd, RD::VertexFormatID &r_vertex_format) {
+	_FORCE_INLINE_ void mesh_instance_surface_get_vertex_arrays_and_format(RID p_mesh_instance, uint64_t p_surface_index, uint32_t p_input_mask, bool p_input_motion_vectors, RID &r_vertex_array_rd, RD::VertexFormatID &r_vertex_format) {
 		MeshInstance *mi = mesh_instance_owner.get_or_null(p_mesh_instance);
 		ERR_FAIL_NULL(mi);
 		Mesh *mesh = mi->mesh;