Refactor: Do not keep a copy of depth buffer in RegionView3D

The depth cache (located in `RegionView3D::depths`) is used for quick
and simple occlusion testing in:
- particle selection,
- "Draw Curve" operator and
- "Interactive Light Track to Cursor" operator,

However, keeping a texture buffer in cache is not a recommended practice.

For displays with high resolution like 8k this represents something
around 132MB.

Also, currently, each call to `ED_view3d_depth_override` invalidates
the depth cache. So that depth is never reused in multiple calls from
an operator (this was not the case in blender 2.79).

This commit allows to create a depth cache and release it in the same
operator. Thus, the buffer is kept in cache for a short time, freeing
up space.

No functional changes.

1 files changed, 1 insertions, 1 deletions

diff --git a/source/blender/editors/space_view3d/view3d_intern.h b/source/blender/editors/space_view3d/view3d_intern.h
index 6f07cb8b44d..0964c2dcbcc 100644
--- a/source/blender/editors/space_view3d/view3d_intern.h
+++ b/source/blender/editors/space_view3d/view3d_intern.h
@@ -137,7 +137,7 @@ void ED_view3d_draw_depth_loop(struct Depsgraph *depsgraph,
                                struct ARegion *region,
                                View3D *v3d);
 
-void view3d_update_depths_rect(struct ARegion *region, struct ViewDepths *d, struct rcti *rect);
+void view3d_depths_rect_create(struct ARegion *region, struct rcti *rect, struct ViewDepths *r_d);
 float view3d_depth_near(struct ViewDepths *d);
 
 /* view3d_select.c */