PixelPaint: Add menu action to toggle pixel grid visibility

You can now toggle on/off the visibility of the pixel grid from
the View menu, if you don't want it shown for some reason.

Userland/Applications/PixelPaint/ImageEditor.cpp

@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
  * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
+ * Copyright (c) 2021, Mustafa Quraish <mustafa@cs.toronto.edu>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -100,7 +101,7 @@ void ImageEditor::paint_event(GUI::PaintEvent& event)
         m_selection.paint(painter);
 
     const float pixel_grid_threshold = 15.0f;
-    if (m_scale > pixel_grid_threshold) {
+    if (m_show_pixel_grid && m_scale > pixel_grid_threshold) {
         auto grid_rect = m_editor_image_rect.intersected(event.rect());
         auto image_rect = enclosing_int_rect(editor_rect_to_image_rect(grid_rect)).inflated(1, 1);
 
@@ -354,6 +355,14 @@ void ImageEditor::set_guide_visibility(bool show_guides)
     update();
 }
 
+void ImageEditor::set_pixel_grid_visibility(bool show_pixel_grid)
+{
+    if (m_show_pixel_grid == show_pixel_grid)
+        return;
+    m_show_pixel_grid = show_pixel_grid;
+    update();
+}
+
 void ImageEditor::layers_did_change()
 {
     update();

Userland/Applications/PixelPaint/ImageEditor.h

@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
  * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
+ * Copyright (c) 2021, Mustafa Quraish <mustafa@cs.toronto.edu>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -94,6 +95,9 @@ public:
     void set_guide_visibility(bool show_guides);
     Function<void(bool)> on_set_guide_visibility;
 
+    bool pixel_grid_visibility() const { return m_show_pixel_grid; }
+    void set_pixel_grid_visibility(bool show_pixel_grid);
+
 private:
     explicit ImageEditor(NonnullRefPtr<Image>);
 
@@ -127,6 +131,7 @@ private:
 
     NonnullRefPtrVector<Guide> m_guides;
     bool m_show_guides { true };
+    bool m_show_pixel_grid { true };
 
     Tool* m_active_tool { nullptr };
 

Userland/Applications/PixelPaint/MainWidget.cpp

@@ -357,6 +357,15 @@ void MainWidget::initialize_menubar(GUI::Window& window)
             if (auto* editor = current_image_editor())
                 editor->clear_guides();
         }));
+    view_menu.add_separator();
+
+    auto show_pixel_grid_action = GUI::Action::create_checkable(
+        "Show Pixel Grid", [&](auto& action) {
+            if (auto* editor = current_image_editor())
+                editor->set_pixel_grid_visibility(action.is_checked());
+        });
+    show_pixel_grid_action->set_checked(true);
+    view_menu.add_action(*show_pixel_grid_action);
 
     auto& tool_menu = window.add_menu("&Tool");
     m_toolbox->for_each_tool([&](auto& tool) {