Annotations: Use flag to determine if the layer is a Ruler

Proposed fix for T70141.

Before, the ruler was using the name of the layer as key, but this is very weak because if the layer name changes, the layer gets an annotation layer.

Now, the layer is marked using a flag and now it's possible to rename it.

Reviewed By: dfelinto

Differential Revision: https://developer.blender.org/D6028

1 files changed, 14 insertions, 4 deletions

diff --git a/source/blender/editors/space_view3d/view3d_gizmo_ruler.c b/source/blender/editors/space_view3d/view3d_gizmo_ruler.c
index 5625333d837..a5b7fac624d 100644
--- a/source/blender/editors/space_view3d/view3d_gizmo_ruler.c
+++ b/source/blender/editors/space_view3d/view3d_gizmo_ruler.c
@@ -407,6 +407,17 @@ static bool view3d_ruler_item_mousemove(RulerInfo *ruler_info,
 /** \name Ruler/Grease Pencil Conversion
  * \{ */
 
+/* Helper: Find the layer created as ruler. */
+static bGPDlayer *view3d_ruler_layer_get(bGPdata *gpd)
+{
+  for (bGPDlayer *gpl = gpd->layers.first; gpl; gpl = gpl->next) {
+    if (gpl->flag & GP_LAYER_IS_RULER) {
+      return gpl;
+    }
+  }
+  return NULL;
+}
+
 #define RULER_ID "RulerData3D"
 static bool view3d_ruler_to_gpencil(bContext *C, wmGizmoGroup *gzgroup)
 {
@@ -427,12 +438,12 @@ static bool view3d_ruler_to_gpencil(bContext *C, wmGizmoGroup *gzgroup)
   }
   gpd = scene->gpd;
 
-  gpl = BLI_findstring(&gpd->layers, ruler_name, offsetof(bGPDlayer, info));
+  gpl = view3d_ruler_layer_get(gpd);
   if (gpl == NULL) {
     gpl = BKE_gpencil_layer_addnew(gpd, ruler_name, false);
     copy_v4_v4(gpl->color, U.gpencil_new_layer_col);
     gpl->thickness = 1;
-    gpl->flag |= GP_LAYER_HIDE;
+    gpl->flag |= GP_LAYER_HIDE | GP_LAYER_IS_RULER;
   }
 
   gpf = BKE_gpencil_layer_getframe(gpl, CFRA, GP_GETFRAME_ADD_NEW);
@@ -485,8 +496,7 @@ static bool view3d_ruler_from_gpencil(const bContext *C, wmGizmoGroup *gzgroup)
 
   if (scene->gpd) {
     bGPDlayer *gpl;
-    const char *ruler_name = RULER_ID;
-    gpl = BLI_findstring(&scene->gpd->layers, ruler_name, offsetof(bGPDlayer, info));
+    gpl = view3d_ruler_layer_get(scene->gpd);
     if (gpl) {
       bGPDframe *gpf;
       gpf = BKE_gpencil_layer_getframe(gpl, CFRA, GP_GETFRAME_USE_PREV);