GPencil: Add material selector to context menus

Now it's possible to select the material in context menu and new menu to select material.

The patch and workflow  has been tested in greasepencil-object branch.

* New Material selector in Draw mode Context menu:

{F8499259}

* Pressing `U`key in Draw mode display material menu.

{F8503224}

Reviewed By: mendio, pepeland

Differential Revision: https://developer.blender.org/D7554

1 files changed, 32 insertions, 2 deletions

diff --git a/release/scripts/startup/bl_ui/properties_grease_pencil_common.py b/release/scripts/startup/bl_ui/properties_grease_pencil_common.py
index 0f6a51ad2d0..fea4406cb8c 100644
--- a/release/scripts/startup/bl_ui/properties_grease_pencil_common.py
+++ b/release/scripts/startup/bl_ui/properties_grease_pencil_common.py
@@ -361,6 +361,35 @@ class GPENCIL_MT_layer_active(Menu):
         layout.operator("gpencil.layer_add", text="New Layer", icon='ADD')
 
 
+class GPENCIL_MT_material_active(Menu):
+    bl_label = "Change Active Material"
+
+    @classmethod
+    def poll(cls, context):
+        ob = context.active_object
+        tool_settings = context.scene.tool_settings
+        mode = tool_settings.gpencil_paint.color_mode
+        if mode != 'MATERIAL':
+            return False
+
+        if ob is None or len(ob.material_slots) == 0:
+            return False
+
+        return True
+
+    def draw(self, context):
+        layout = self.layout
+        layout.operator_context = 'INVOKE_REGION_WIN'
+        ob = context.active_object
+        mat_active = ob.active_material
+
+        for slot in ob.material_slots:
+            mat = slot.material
+            if mat:
+                icon = mat.id_data.preview.icon_id
+                layout.operator("gpencil.material_set", text=mat.name, icon_value=icon).slot = mat.name
+
+
 class GPENCIL_MT_gpencil_draw_delete(Menu):
     bl_label = "Delete"
 
@@ -632,8 +661,8 @@ class GreasePencilMaterialsPanel:
                 if ob.data.use_stroke_edit_mode:
                     row = layout.row(align=True)
                     row.operator("gpencil.stroke_change_color", text="Assign")
-                    row.operator("gpencil.select_material", text="Select").deselect = False
-                    row.operator("gpencil.select_material", text="Deselect").deselect = True
+                    row.operator("gpencil.material_select", text="Select").deselect = False
+                    row.operator("gpencil.material_select", text="Deselect").deselect = True
         # stroke color
             ma = None
             if is_view3d and brush is not None:
@@ -931,6 +960,7 @@ classes = (
     GPENCIL_MT_cleanup,
     GPENCIL_MT_move_to_layer,
     GPENCIL_MT_layer_active,
+    GPENCIL_MT_material_active,
 
     GPENCIL_MT_gpencil_draw_delete,
     GPENCIL_MT_layer_mask_menu,