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.

5 files changed, 8 insertions, 8 deletions

diff --git a/source/blender/editors/gpencil/annotate_paint.c b/source/blender/editors/gpencil/annotate_paint.c
index c155587e95a..e3c6fd8f878 100644
--- a/source/blender/editors/gpencil/annotate_paint.c
+++ b/source/blender/editors/gpencil/annotate_paint.c
@@ -667,7 +667,7 @@ static short annotation_stroke_addpoint(tGPsdata *p,
                                  (ts->annotate_v3d_align & GP_PROJECT_DEPTH_STROKE) ?
                                      V3D_DEPTH_GPENCIL_ONLY :
                                      V3D_DEPTH_NO_GPENCIL,
-                                 false);
+                                 NULL);
       }
 
       /* convert screen-coordinates to appropriate coordinates (and store them) */
@@ -1226,7 +1226,7 @@ static void annotation_stroke_doeraser(tGPsdata *p)
     if (p->flags & GP_PAINTFLAG_V3D_ERASER_DEPTH) {
       View3D *v3d = p->area->spacedata.first;
       view3d_region_operator_needs_opengl(p->win, p->region);
-      ED_view3d_depth_override(p->depsgraph, p->region, v3d, NULL, V3D_DEPTH_NO_GPENCIL, false);
+      ED_view3d_depth_override(p->depsgraph, p->region, v3d, NULL, V3D_DEPTH_NO_GPENCIL, NULL);
     }
   }
 
@@ -1706,7 +1706,7 @@ static void annotation_paint_strokeend(tGPsdata *p)
                              (ts->annotate_v3d_align & GP_PROJECT_DEPTH_STROKE) ?
                                  V3D_DEPTH_GPENCIL_ONLY :
                                  V3D_DEPTH_NO_GPENCIL,
-                             false);
+                             NULL);
   }
 
   /* check if doing eraser or not */
diff --git a/source/blender/editors/gpencil/gpencil_fill.c b/source/blender/editors/gpencil/gpencil_fill.c
index f74e211dd65..5c4e2de6aa8 100644
--- a/source/blender/editors/gpencil/gpencil_fill.c
+++ b/source/blender/editors/gpencil/gpencil_fill.c
@@ -1373,7 +1373,7 @@ static void gpencil_get_depth_array(tGPDfill *tgpf)
     /* need to restore the original projection settings before packing up */
     view3d_region_operator_needs_opengl(tgpf->win, tgpf->region);
     ED_view3d_depth_override(
-        tgpf->depsgraph, tgpf->region, tgpf->v3d, NULL, V3D_DEPTH_NO_GPENCIL, false);
+        tgpf->depsgraph, tgpf->region, tgpf->v3d, NULL, V3D_DEPTH_NO_GPENCIL, NULL);
 
     /* Since strokes are so fine, when using their depth we need a margin
      * otherwise they might get missed. */
diff --git a/source/blender/editors/gpencil/gpencil_paint.c b/source/blender/editors/gpencil/gpencil_paint.c
index e40748e5f6e..638994bbc2a 100644
--- a/source/blender/editors/gpencil/gpencil_paint.c
+++ b/source/blender/editors/gpencil/gpencil_paint.c
@@ -1744,7 +1744,7 @@ static void gpencil_stroke_doeraser(tGPsdata *p)
     if ((gp_settings != NULL) && (gp_settings->flag & GP_BRUSH_OCCLUDE_ERASER)) {
       View3D *v3d = p->area->spacedata.first;
       view3d_region_operator_needs_opengl(p->win, p->region);
-      ED_view3d_depth_override(p->depsgraph, p->region, v3d, NULL, V3D_DEPTH_NO_GPENCIL, false);
+      ED_view3d_depth_override(p->depsgraph, p->region, v3d, NULL, V3D_DEPTH_NO_GPENCIL, NULL);
     }
   }
 
@@ -2334,7 +2334,7 @@ static void gpencil_paint_strokeend(tGPsdata *p)
                              (ts->gpencil_v3d_align & GP_PROJECT_DEPTH_STROKE) ?
                                  V3D_DEPTH_GPENCIL_ONLY :
                                  V3D_DEPTH_NO_GPENCIL,
-                             false);
+                             NULL);
   }
 
   /* check if doing eraser or not */
diff --git a/source/blender/editors/gpencil/gpencil_primitive.c b/source/blender/editors/gpencil/gpencil_primitive.c
index 5f02bbf0a77..a2b4e5dee64 100644
--- a/source/blender/editors/gpencil/gpencil_primitive.c
+++ b/source/blender/editors/gpencil/gpencil_primitive.c
@@ -792,7 +792,7 @@ static void gpencil_primitive_update_strokes(bContext *C, tGPDprimitive *tgpi)
                              (ts->gpencil_v3d_align & GP_PROJECT_DEPTH_STROKE) ?
                                  V3D_DEPTH_GPENCIL_ONLY :
                                  V3D_DEPTH_NO_GPENCIL,
-                             false);
+                             NULL);
 
     depth_arr = MEM_mallocN(sizeof(float) * gps->totpoints, "depth_points");
     tGPspoint *ptc = &points2D[0];
diff --git a/source/blender/editors/gpencil/gpencil_utils.c b/source/blender/editors/gpencil/gpencil_utils.c
index c9ef340b9d3..4da21bd05ee 100644
--- a/source/blender/editors/gpencil/gpencil_utils.c
+++ b/source/blender/editors/gpencil/gpencil_utils.c
@@ -680,7 +680,7 @@ void gpencil_point_conversion_init(bContext *C, GP_SpaceConversion *r_gsc)
     view3d_operator_needs_opengl(C);
 
     view3d_region_operator_needs_opengl(win, region);
-    ED_view3d_depth_override(depsgraph, region, v3d, NULL, V3D_DEPTH_NO_GPENCIL, false);
+    ED_view3d_depth_override(depsgraph, region, v3d, NULL, V3D_DEPTH_NO_GPENCIL, NULL);
 
     /* for camera view set the subrect */
     if (rv3d->persp == RV3D_CAMOB) {