MaskEditor: draw active layer on top

Instead of drawing the mask layers in the sequence of their occurence, draw the active mask *always* on top.

Implementation:
- move drawing loop for splines to separate static function
- draw active mask last

Example: lowest layer is active, yet still drawn on top.
{F12140355}

This is part of an effort to make mask editing more intuitive & easy to use: https://developer.blender.org/T93097

Reviewed By: sergey

Differential Revision: https://developer.blender.org/D13372

1 files changed, 38 insertions, 18 deletions

diff --git a/source/blender/editors/mask/mask_draw.c b/source/blender/editors/mask/mask_draw.c
index 22232e9c87e..92e774bfe86 100644
--- a/source/blender/editors/mask/mask_draw.c
+++ b/source/blender/editors/mask/mask_draw.c
@@ -587,6 +587,35 @@ static void draw_spline_curve(const bContext *C,
   }
 }
 
+static void draw_layer_splines(const bContext *C,
+                               MaskLayer *layer,
+                               const char draw_flag,
+                               const char draw_type,
+                               const int width,
+                               const int height,
+                               const bool is_active)
+{
+  LISTBASE_FOREACH (MaskSpline *, spline, &layer->splines) {
+    /* draw curve itself first... */
+    draw_spline_curve(C, layer, spline, draw_flag, draw_type, is_active, width, height);
+
+    if (!(layer->visibility_flag & MASK_HIDE_SELECT)) {
+      /* ...and then handles over the curve so they're nicely visible */
+      draw_spline_points(C, layer, spline, draw_flag, draw_type);
+    }
+
+    /* show undeform for testing */
+    if (0) {
+      void *back = spline->points_deform;
+
+      spline->points_deform = NULL;
+      draw_spline_curve(C, layer, spline, draw_flag, draw_type, is_active, width, height);
+      draw_spline_points(C, layer, spline, draw_flag, draw_type);
+      spline->points_deform = back;
+    }
+  }
+}
+
 static void draw_mask_layers(const bContext *C,
                              Mask *mask,
                              const char draw_flag,
@@ -600,6 +629,7 @@ static void draw_mask_layers(const bContext *C,
   MaskLayer *mask_layer;
   int i;
 
+  MaskLayer *active = NULL;
   for (mask_layer = mask->masklayers.first, i = 0; mask_layer != NULL;
        mask_layer = mask_layer->next, i++) {
     const bool is_active = (i == mask->masklay_act);
@@ -608,26 +638,16 @@ static void draw_mask_layers(const bContext *C,
       continue;
     }
 
-    LISTBASE_FOREACH (MaskSpline *, spline, &mask_layer->splines) {
-
-      /* draw curve itself first... */
-      draw_spline_curve(C, mask_layer, spline, draw_flag, draw_type, is_active, width, height);
-
-      if (!(mask_layer->visibility_flag & MASK_HIDE_SELECT)) {
-        /* ...and then handles over the curve so they're nicely visible */
-        draw_spline_points(C, mask_layer, spline, draw_flag, draw_type);
-      }
+    if (is_active) {
+      active = mask_layer;
+      continue;
+    }
 
-      /* show undeform for testing */
-      if (0) {
-        void *back = spline->points_deform;
+    draw_layer_splines(C, mask_layer, draw_flag, draw_type, width, height, is_active);
+  }
 
-        spline->points_deform = NULL;
-        draw_spline_curve(C, mask_layer, spline, draw_flag, draw_type, is_active, width, height);
-        draw_spline_points(C, mask_layer, spline, draw_flag, draw_type);
-        spline->points_deform = back;
-      }
-    }
+  if (active != NULL) {
+    draw_layer_splines(C, active, draw_flag, draw_type, width, height, true);
   }
 
   GPU_program_point_size(false);