GPv3: Add Assign material menu

Adds a menu to assign a material from a list as is in GPv2.

Related to #114190.

Pull Request: https://projects.blender.org/blender/blender/pulls/114637

scripts/startup/bl_ui/space_view3d.py

@@ -5831,6 +5831,7 @@ class VIEW3D_MT_edit_greasepencil_stroke(Menu):
 
         layout.separator()
 
+        layout.menu("VIEW3D_MT_grease_pencil_assign_material")
         layout.operator("grease_pencil.set_active_material")
 
         layout.separator()
@@ -8139,6 +8140,27 @@ class VIEW3D_MT_greasepencil_material_active(Menu):
                 layout.operator("grease_pencil.set_material", text=mat.name, icon_value=icon).slot = mat.name
 
 
+class VIEW3D_MT_grease_pencil_assign_material(Menu):
+    bl_label = "Assign Material"
+
+    def draw(self, context):
+        layout = self.layout
+        ob = context.active_object
+        mat_active = ob.active_material
+
+        if len(ob.material_slots) == 0:
+            row = layout.row()
+            row.label(text="No Materials")
+            row.enabled = False
+            return
+
+        for slot in ob.material_slots:
+            mat = slot.material
+            if mat:
+                layout.operator("grease_pencil.stroke_material_set", text=mat.name,
+                                icon='LAYER_ACTIVE' if mat == mat_active else 'BLANK1').material = mat.name
+
+
 class VIEW3D_MT_greasepencil_edit_context_menu(Menu):
     bl_label = ""
 
@@ -8198,6 +8220,11 @@ class VIEW3D_MT_greasepencil_edit_context_menu(Menu):
 
             col.separator()
 
+            col.menu("VIEW3D_MT_grease_pencil_assign_material")
+            col.operator("grease_pencil.set_active_material", text="Set as Active Material")
+
+            col.separator()
+
             col.menu("VIEW3D_MT_mirror")
 
 
@@ -8894,6 +8921,7 @@ classes = (
     VIEW3D_MT_gpencil_autoweights,
     VIEW3D_MT_gpencil_edit_context_menu,
     VIEW3D_MT_greasepencil_edit_context_menu,
+    VIEW3D_MT_grease_pencil_assign_material,
     VIEW3D_MT_edit_greasepencil,
     VIEW3D_MT_edit_greasepencil_delete,
     VIEW3D_MT_edit_greasepencil_stroke,

source/blender/editors/grease_pencil/intern/grease_pencil_edit.cc

@@ -13,6 +13,7 @@
 #include "BLI_math_vector_types.hh"
 #include "BLI_span.hh"
 #include "BLI_stack.hh"
+#include "BLT_translation.h"
 
 #include "DNA_material_types.h"
 
@@ -20,7 +21,9 @@
 #include "BKE_context.hh"
 #include "BKE_curves_utils.hh"
 #include "BKE_grease_pencil.hh"
+#include "BKE_lib_id.h"
 #include "BKE_material.h"
+#include "BKE_report.h"
 
 #include "RNA_access.hh"
 #include "RNA_define.hh"
@@ -978,12 +981,29 @@ static void GREASE_PENCIL_OT_delete_frame(wmOperatorType *ot)
 /** \name Stroke Material Set Operator
  * \{ */
 
-static int grease_pencil_stroke_material_set_exec(bContext *C, wmOperator * /*op*/)
+static int grease_pencil_stroke_material_set_exec(bContext *C, wmOperator *op)
 {
+  using namespace blender;
+  Main *bmain = CTX_data_main(C);
   const Scene *scene = CTX_data_scene(C);
   Object *object = CTX_data_active_object(C);
   GreasePencil &grease_pencil = *static_cast<GreasePencil *>(object->data);
-  const int material_index = object->actcol - 1;
+  Material *ma = nullptr;
+  char name[MAX_ID_NAME - 2];
+  RNA_string_get(op->ptr, "material", name);
+
+  int material_index = object->actcol - 1;
+
+  if (name[0] != '\0') {
+    ma = reinterpret_cast<Material *>(BKE_libblock_find_name(bmain, ID_MA, name));
+    if (ma == nullptr) {
+      BKE_reportf(op->reports, RPT_WARNING, TIP_("Material '%s' could not be found"), name);
+      return OPERATOR_CANCELLED;
+    }
+
+    /* Find slot index. */
+    material_index = BKE_object_material_index_get(object, ma);
+  }
 
   if (material_index == -1) {
     return OPERATOR_CANCELLED;
@@ -1022,6 +1042,10 @@ static void GREASE_PENCIL_OT_stroke_material_set(wmOperatorType *ot)
   ot->poll = editable_grease_pencil_poll;
 
   ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+  ot->prop = RNA_def_string(
+      ot->srna, "material", nullptr, MAX_ID_NAME - 2, "Material", "Name of the material");
+  RNA_def_property_flag(ot->prop, PROP_SKIP_SAVE);
 }
 /** \} */