1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CHROME_BROWSER_UI_GTK_NINE_BOX_H_
6#define CHROME_BROWSER_UI_GTK_NINE_BOX_H_
7#pragma once
8
9#include <gtk/gtk.h>
10
11// A NineBox manages a set of source images representing a 3x3 grid, where
12// non-corner images can be tiled to make a larger image.  It's used to
13// use bitmaps for constructing image-based resizable widgets like buttons.
14//
15// If you want just a vertical image that stretches in height but is fixed
16// in width, only pass in images for the left column (leave others NULL).
17// Similarly, for a horizontal image that stretches in width but is fixed in
18// height, only pass in images for the top row.
19//
20// TODO(port): add support for caching server-side pixmaps of prerendered
21// nineboxes.
22class NineBox {
23 public:
24  // Construct a NineBox with nine images.  Images are specified using resource
25  // ids that will be passed to the resource bundle.  Use 0 for no image.
26  NineBox(int top_left, int top, int top_right, int left, int center, int right,
27          int bottom_left, int bottom, int bottom_right);
28
29  // Construct a NineBox from a single image and insets indicating the sizes
30  // of the edges and corners.
31  NineBox(int image, int top_margin, int bottom_margin, int left_margin,
32          int right_margin);
33  ~NineBox();
34
35  // Render the NineBox to |dst|.
36  // The images will be tiled to fit into the widget.
37  void RenderToWidget(GtkWidget* dst) const;
38
39  // As above, but rendered partially transparent.
40  void RenderToWidgetWithOpacity(GtkWidget* dst, double opacity) const;
41
42  // Render the top row of images to |dst| between |x1| and |x1| + |width|.
43  // This is split from RenderToWidget so the toolbar can use it.
44  void RenderTopCenterStrip(cairo_t* cr, int x, int y, int width) const;
45
46  // Change all pixels that are white in |images_| to have 0 opacity.
47  void ChangeWhiteToTransparent();
48
49  // Set the shape of |widget| to match that of the ninebox. Note that |widget|
50  // must have its own window and be allocated. Also, currently only the top
51  // three images are used.
52  // TODO(estade): extend this function to use all 9 images (if it's ever
53  // needed).
54  void ContourWidget(GtkWidget* widget) const;
55
56 private:
57  GdkPixbuf* images_[9];
58  bool unref_pixbufs_on_destroy_;
59};
60
61#endif  // CHROME_BROWSER_UI_GTK_NINE_BOX_H_
62