Repository: godotengine/godot
File: editor/plugins/camera_3d_editor_plugin.cpp (C++)

Code before:
			Node3DEditor::get_singleton()->set_custom_camera(p_camera);
		} else {
			Node3DEditor::get_singleton()->set_custom_camera(nullptr);
		}
	}
}

Camera3DEditor::Camera3DEditor() {
	preview = memnew(Button);
	add_child(preview);

	preview->set_text(TTR("Preview"));
	preview->set_toggle_mode(true);
	preview->set_anchor(SIDE_LEFT, Control::ANCHOR_END);
	preview->set_anchor(SIDE_RIGHT, Control::ANCHOR_END);
	preview->set_offset(SIDE_LEFT, -60);
	preview->set_offset(SIDE_RIGHT, 0);
	preview->set_offset(SIDE_TOP, 0);
	preview->set_offset(SIDE_BOTTOM, 10);
	preview->connect("pressed", callable_mp(this, &Camera3DEditor::_pressed));
}

void Camera3DEditorPlugin::edit(Object *p_object) {
	Node3DEditor::get_singleton()->set_can_preview(Object::cast_to<Camera3D>(p_object));
	//camera_editor->edit(Object::cast_to<Node>(p_object));
}

bool Camera3DEditorPlugin::handles(Object *p_object) const {
	return p_object->is_class("Camera3D");
}

void Camera3DEditorPlugin::make_visible(bool p_visible) {
	if (p_visible) {
		//Node3DEditor::get_singleton()->set_can_preview(Object::cast_to<Camera3D>(p_object));
	} else {
		Node3DEditor::get_singleton()->set_can_preview(nullptr);
	}
}

Camera3DEditorPlugin::Camera3DEditorPlugin() {
	/*	camera_editor = memnew( CameraEditor );
	EditorNode::get_singleton()->get_main_screen_control()->add_child(camera_editor);

	camera_editor->set_anchor(SIDE_LEFT,Control::ANCHOR_END);
	camera_editor->set_anchor(SIDE_RIGHT,Control::ANCHOR_END);
	camera_editor->set_offset(SIDE_LEFT,60);
	camera_editor->set_offset(SIDE_RIGHT,0);
	camera_editor->set_offset(SIDE_TOP,0);
	camera_editor->set_offset(SIDE_BOTTOM,10);



Review comment (suggestion):
This function can be merged with `_update_sub_viewport_size()`, because it's used only once.
EDIT:
Or it can be moved, as commented below.

Code after:
		Node3DEditor::get_singleton()->set_custom_camera(nullptr);
	} else {
		if (preview->is_pressed()) {
			Node3DEditor::get_singleton()->set_custom_camera(p_camera);
		} else {
			Node3DEditor::get_singleton()->set_custom_camera(nullptr);
		}
	}
}

Camera3DEditor::Camera3DEditor() {
	preview = memnew(Button);
	add_child(preview);

	preview->set_text(TTR("Preview"));
	preview->set_toggle_mode(true);
	preview->set_anchor(SIDE_LEFT, Control::ANCHOR_END);
	preview->set_anchor(SIDE_RIGHT, Control::ANCHOR_END);
	preview->set_offset(SIDE_LEFT, -60);
	preview->set_offset(SIDE_RIGHT, 0);
	preview->set_offset(SIDE_TOP, 0);
	preview->set_offset(SIDE_BOTTOM, 10);
	preview->connect("pressed", callable_mp(this, &Camera3DEditor::_pressed));
}

void Camera3DPreview::_update_sub_viewport_size() {
	sub_viewport->set_size(Node3DEditor::get_camera_viewport_size(camera));
}

Camera3DPreview::Camera3DPreview(Camera3D *p_camera) :
		TexturePreview(nullptr, false), camera(p_camera), sub_viewport(memnew(SubViewport)) {
	RenderingServer::get_singleton()->viewport_attach_camera(sub_viewport->get_viewport_rid(), camera->get_camera());
	add_child(sub_viewport);

	TextureRect *display = get_texture_display();
	display->set_texture(sub_viewport->get_texture());
	sub_viewport->connect("size_changed", callable_mp((CanvasItem *)display, &CanvasItem::queue_redraw));

	ProjectSettings::get_singleton()->connect("settings_changed", callable_mp(this, &Camera3DPreview::_update_sub_viewport_size));
	_update_sub_viewport_size();
}

bool EditorInspectorPluginCamera3DPreview::can_handle(Object *p_object) {
	return Object::cast_to<Camera3D>(p_object) != nullptr;
}

void EditorInspectorPluginCamera3DPreview::parse_begin(Object *p_object) {
	Camera3D *camera = Object::cast_to<Camera3D>(p_object);
	Camera3DPreview *preview = memnew(Camera3DPreview(camera));
	add_custom_control(preview);
}