PixelPaint: Add Crop to Selection Action

In addition to adding the action, this commit also makes the
`did_change_rect()` method take in an optional rect, which
represents the new rect position. By default it is the same as
`rect()`.

When we are cropping an image, we don't want to move the whole
cropped section to the top-left of the original image in the
ImageEditor widget, so this allows us to keep the cropped image's
position fixed.

Userland/Applications/PixelPaint/Image.cpp

@@ -458,10 +458,11 @@ void Image::did_change(Gfx::IntRect const& a_modified_rect)
  client->image_did_change(modified_rect);
 }
 
-void Image::did_change_rect()
+void Image::did_change_rect(Gfx::IntRect const& a_modified_rect)
 {
+ auto modified_rect = a_modified_rect.is_empty() ? this->rect() : a_modified_rect;
  for (auto* client : m_clients)
- client->image_did_change_rect(rect());
+ client->image_did_change_rect(modified_rect);
 }
 
 ImageUndoCommand::ImageUndoCommand(Image& image)
@@ -518,4 +519,17 @@ void Image::rotate(Gfx::RotationDirection direction)
  did_change_rect();
 }
 
+void Image::crop(Gfx::IntRect const& cropped_rect)
+{
+ for (auto& layer : m_layers) {
+ auto cropped = layer.bitmap().cropped(cropped_rect);
+ VERIFY(cropped);
+ layer.set_bitmap(*cropped);
+ layer.did_modify_bitmap(rect());
+ }
+
+ m_size = { cropped_rect.width(), cropped_rect.height() };
+ did_change_rect(cropped_rect);
+}
+
 }

Userland/Applications/PixelPaint/Image.h

@@ -101,12 +101,13 @@ class Image : public RefCounted<Image> {
 
  void flip(Gfx::Orientation orientation);
  void rotate(Gfx::RotationDirection direction);
+ void crop(Gfx::IntRect const& rect);
 
 private:
  explicit Image(Gfx::IntSize const&);
 
  void did_change(Gfx::IntRect const& modified_rect = {});
- void did_change_rect();
+ void did_change_rect(Gfx::IntRect const& modified_rect = {});
  void did_modify_layer_stack();
 
  String m_path;

Userland/Applications/PixelPaint/MainWidget.cpp

@@ -375,6 +375,17 @@ void MainWidget::initialize_menubar(GUI::Window& window)
  return;
  editor->image().rotate(Gfx::RotationDirection::Clockwise);
  }));
+ image_menu.add_separator();
+ image_menu.add_action(GUI::Action::create(
+ "&Crop To Selection", [&](auto&) {
+ auto* editor = current_image_editor();
+ // FIXME: disable this action if there is no selection
+ if (!editor || editor->selection().is_empty())
+ return;
+ auto crop_rect = editor->selection().bounding_rect();
+ editor->image().crop(crop_rect);
+ editor->selection().clear();
+ }));
 
  auto& layer_menu = window.add_menu("&Layer");
  layer_menu.add_action(GUI::Action::create(