Make the toolbar background themed on Linux.

Add a class for managing images for scalable themed widgets, and then
implement the toolbar on top of this.

Review URL: http://codereview.chromium.org/21390


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@9898 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 90 insertions, 0 deletions

diff --git a/chrome/browser/gtk/nine_box.cc b/chrome/browser/gtk/nine_box.cc
new file mode 100644
index 0000000..98164d9
--- /dev/null
+++ b/chrome/browser/gtk/nine_box.cc
@@ -0,0 +1,90 @@
+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/gtk/nine_box.h"
+
+#include "base/logging.h"
+
+namespace {
+
+// Draw pixbuf |src| into |dst| at position (x, y).
+// Shorthand for gdk_pixbuf_copy_area.
+void DrawPixbuf(GdkPixbuf* src, GdkPixbuf* dst, int x, int y) {
+  gdk_pixbuf_copy_area(src, 0, 0,
+                       gdk_pixbuf_get_width(src),
+                       gdk_pixbuf_get_height(src),
+                       dst, x, y);
+}
+
+}  // anonymous namespace
+
+NineBox::NineBox(GdkPixbuf* images[9]) {
+  memcpy(images_, images, 9*sizeof(GdkPixbuf*));
+}
+
+NineBox::~NineBox() {
+  for (int i = 0; i < 9; ++i) {
+    if (images_[i])
+      gdk_pixbuf_unref(images_[i]);
+  }
+}
+
+void NineBox::RenderToPixbuf(GdkPixbuf* dst) {
+  // This function paints one row at a time.
+  // To make indexing sane, |images| points at the current row of images,
+  // so images[0] always refers to the left-most image of the current row.
+  GdkPixbuf** images = &images_[0];
+
+  // x, y coordinate of bottom right corner drawing offset.
+  int x = gdk_pixbuf_get_width(dst) - gdk_pixbuf_get_width(images[2]);
+  int y = gdk_pixbuf_get_height(dst) - gdk_pixbuf_get_height(images[2]);
+
+  DrawPixbuf(images[0], dst, 0, 0);
+  RenderTopCenterStrip(dst, gdk_pixbuf_get_width(images[0]), x);
+  DrawPixbuf(images[2], dst, x, 0);
+
+  // Center row.  Needs vertical tiling.
+  images = &images_[1 * 3];
+  TileImage(images[0], dst,
+            0, gdk_pixbuf_get_height(images[0]),
+            0, y);
+  // TODO(port): tile center image if it exists.
+  DCHECK(images[1] == NULL);
+  TileImage(images[2], dst,
+            x, gdk_pixbuf_get_height(images[0]),
+            x, y);
+
+  // Bottom row.
+  images = &images_[2 * 3];
+  DrawPixbuf(images[0], dst, 0, y);
+  TileImage(images[1], dst,
+            gdk_pixbuf_get_width(images[0]), y,
+            x, y);
+  DrawPixbuf(images[2], dst, x, y);
+}
+
+void NineBox::RenderTopCenterStrip(GdkPixbuf* dst, int x1, int x2) {
+  TileImage(images_[1], dst,
+            x1, 0,
+            x2, 0);
+}
+
+void NineBox::TileImage(GdkPixbuf* src, GdkPixbuf* dst,
+                        int x1, int y1, int x2, int y2) {
+  const int width = gdk_pixbuf_get_width(src);
+  const int height = gdk_pixbuf_get_height(src);
+
+  // Compute delta x or y.
+  int dx = 0, dy = 0;
+  if (x2 > x1)
+    dx = width;
+  if (y2 > y1)
+    dy = height;
+
+  for (int x = x1, y = y1;
+       x + width <= x2 || y + height <= y2;
+       x += dx, y += dy) {
+    DrawPixbuf(src, dst, x, y);
+  }
+}