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      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 #include "chrome/browser/ui/gtk/nine_box.h"
      6 
      7 #include "base/basictypes.h"
      8 #include "base/i18n/rtl.h"
      9 #include "base/logging.h"
     10 #include "ui/base/resource/resource_bundle.h"
     11 #include "ui/gfx/gtk_util.h"
     12 #include "ui/gfx/point.h"
     13 
     14 namespace {
     15 
     16 // Draw pixbuf |src| into |dst| at position (x, y).
     17 void DrawPixbuf(cairo_t* cr, GdkPixbuf* src, int x, int y, double alpha) {
     18   gdk_cairo_set_source_pixbuf(cr, src, x, y);
     19   cairo_paint_with_alpha(cr, alpha);
     20 }
     21 
     22 // Tile pixbuf |src| across |cr| at |x|, |y| for |width| and |height|.
     23 void TileImage(cairo_t* cr, GdkPixbuf* src,
     24                int x, int y, int width, int height, double alpha) {
     25   if (alpha == 1.0) {
     26     gdk_cairo_set_source_pixbuf(cr, src, x, y);
     27     cairo_pattern_set_extend(cairo_get_source(cr), CAIRO_EXTEND_REPEAT);
     28     cairo_rectangle(cr, x, y, width, height);
     29     cairo_fill(cr);
     30   } else {
     31     // Since there is no easy way to apply a mask to a fill operation, we create
     32     // a secondary surface and tile into that, then paint it with |alpha|.
     33     cairo_surface_t* surface = cairo_image_surface_create(
     34         CAIRO_FORMAT_ARGB32, width, height);
     35     cairo_t* tiled = cairo_create(surface);
     36     gdk_cairo_set_source_pixbuf(tiled, src, 0, 0);
     37     cairo_pattern_set_extend(cairo_get_source(tiled), CAIRO_EXTEND_REPEAT);
     38     cairo_rectangle(tiled, 0, 0, width, height);
     39     cairo_fill(tiled);
     40 
     41     cairo_set_source_surface(cr, surface, x, y);
     42     cairo_paint_with_alpha(cr, alpha);
     43 
     44     cairo_destroy(tiled);
     45     cairo_surface_destroy(surface);
     46   }
     47 }
     48 
     49 }  // namespace
     50 
     51 NineBox::NineBox(int top_left, int top, int top_right, int left, int center,
     52                  int right, int bottom_left, int bottom, int bottom_right)
     53     : unref_pixbufs_on_destroy_(false) {
     54   ResourceBundle& rb = ResourceBundle::GetSharedInstance();
     55   images_[0] = top_left ? rb.GetPixbufNamed(top_left) : NULL;
     56   images_[1] = top ? rb.GetPixbufNamed(top) : NULL;
     57   images_[2] = top_right ? rb.GetPixbufNamed(top_right) : NULL;
     58   images_[3] = left ? rb.GetPixbufNamed(left) : NULL;
     59   images_[4] = center ? rb.GetPixbufNamed(center) : NULL;
     60   images_[5] = right ? rb.GetPixbufNamed(right) : NULL;
     61   images_[6] = bottom_left ? rb.GetPixbufNamed(bottom_left) : NULL;
     62   images_[7] = bottom ? rb.GetPixbufNamed(bottom) : NULL;
     63   images_[8] = bottom_right ? rb.GetPixbufNamed(bottom_right) : NULL;
     64 }
     65 
     66 NineBox::NineBox(int image, int top_margin, int bottom_margin, int left_margin,
     67                  int right_margin)
     68     : unref_pixbufs_on_destroy_(true) {
     69   ResourceBundle& rb = ResourceBundle::GetSharedInstance();
     70   GdkPixbuf* pixbuf = rb.GetPixbufNamed(image);
     71   int width = gdk_pixbuf_get_width(pixbuf);
     72   int height = gdk_pixbuf_get_height(pixbuf);
     73   int inset_width = left_margin + right_margin;
     74   int inset_height = top_margin + bottom_margin;
     75 
     76   images_[0] = gdk_pixbuf_new_subpixbuf(pixbuf, 0, 0, left_margin, top_margin);
     77   images_[1] = gdk_pixbuf_new_subpixbuf(pixbuf, left_margin, 0,
     78                                         width - inset_width, top_margin);
     79   images_[2] = gdk_pixbuf_new_subpixbuf(pixbuf, width - right_margin, 0,
     80                                         right_margin, top_margin);
     81   images_[3] = gdk_pixbuf_new_subpixbuf(pixbuf, 0, top_margin,
     82                                         left_margin, height - inset_height);
     83   images_[4] = gdk_pixbuf_new_subpixbuf(pixbuf, left_margin, top_margin,
     84                                         width - inset_width,
     85                                         height - inset_height);
     86   images_[5] = gdk_pixbuf_new_subpixbuf(pixbuf, width - right_margin,
     87                                         top_margin, right_margin,
     88                                         height - inset_height);
     89   images_[6] = gdk_pixbuf_new_subpixbuf(pixbuf, 0, height - bottom_margin,
     90                                         left_margin, bottom_margin);
     91   images_[7] = gdk_pixbuf_new_subpixbuf(pixbuf, left_margin,
     92                                         height - bottom_margin,
     93                                         width - inset_width, bottom_margin);
     94   images_[8] = gdk_pixbuf_new_subpixbuf(pixbuf, width - right_margin,
     95                                         height - bottom_margin,
     96                                         right_margin, bottom_margin);
     97 }
     98 
     99 NineBox::~NineBox() {
    100   if (unref_pixbufs_on_destroy_) {
    101     for (int i = 0; i < 9; i++) {
    102       g_object_unref(images_[i]);
    103     }
    104   }
    105 }
    106 
    107 void NineBox::RenderToWidget(GtkWidget* dst) const {
    108   RenderToWidgetWithOpacity(dst, 1.0);
    109 }
    110 
    111 void NineBox::RenderToWidgetWithOpacity(GtkWidget* dst, double opacity) const {
    112   int dst_width = dst->allocation.width;
    113   int dst_height = dst->allocation.height;
    114 
    115   // The upper-left and lower-right corners of the center square in the
    116   // rendering of the ninebox.
    117   int x1 = gdk_pixbuf_get_width(images_[0]);
    118   int y1 = gdk_pixbuf_get_height(images_[0]);
    119   int x2 = images_[2] ? dst_width - gdk_pixbuf_get_width(images_[2]) : x1;
    120   int y2 = images_[6] ? dst_height - gdk_pixbuf_get_height(images_[6]) : y1;
    121   // Paint nothing if there's not enough room.
    122   if (x2 < x1 || y2 < y1)
    123     return;
    124 
    125   cairo_t* cr = gdk_cairo_create(GDK_DRAWABLE(dst->window));
    126   // For widgets that have their own window, the allocation (x,y) coordinates
    127   // are GdkWindow relative. For other widgets, the coordinates are relative
    128   // to their container.
    129   if (GTK_WIDGET_NO_WINDOW(dst)) {
    130     // Transform our cairo from window to widget coordinates.
    131     cairo_translate(cr, dst->allocation.x, dst->allocation.y);
    132   }
    133 
    134   if (base::i18n::IsRTL()) {
    135     cairo_translate(cr, dst_width, 0.0f);
    136     cairo_scale(cr, -1.0f, 1.0f);
    137   }
    138 
    139   // Top row, center image is horizontally tiled.
    140   if (images_[0])
    141     DrawPixbuf(cr, images_[0], 0, 0, opacity);
    142   if (images_[1])
    143     TileImage(cr, images_[1], x1, 0, x2 - x1, y1, opacity);
    144   if (images_[2])
    145     DrawPixbuf(cr, images_[2], x2, 0, opacity);
    146 
    147   // Center row, all images are vertically tiled, center is horizontally tiled.
    148   if (images_[3])
    149     TileImage(cr, images_[3], 0, y1, x1, y2 - y1, opacity);
    150   if (images_[4])
    151     TileImage(cr, images_[4], x1, y1, x2 - x1, y2 - y1, opacity);
    152   if (images_[5])
    153     TileImage(cr, images_[5], x2, y1, dst_width - x2, y2 - y1, opacity);
    154 
    155   // Bottom row, center image is horizontally tiled.
    156   if (images_[6])
    157     DrawPixbuf(cr, images_[6], 0, y2, opacity);
    158   if (images_[7])
    159     TileImage(cr, images_[7], x1, y2, x2 - x1, dst_height - y2, opacity);
    160   if (images_[8])
    161     DrawPixbuf(cr, images_[8], x2, y2, opacity);
    162 
    163   cairo_destroy(cr);
    164 }
    165 
    166 void NineBox::RenderTopCenterStrip(cairo_t* cr, int x, int y,
    167                                    int width) const {
    168   const int height = gdk_pixbuf_get_height(images_[1]);
    169   TileImage(cr, images_[1], x, y, width, height, 1.0);
    170 }
    171 
    172 void NineBox::ChangeWhiteToTransparent() {
    173   for (int image_idx = 0; image_idx < 9; ++image_idx) {
    174     GdkPixbuf* pixbuf = images_[image_idx];
    175     if (!pixbuf)
    176       continue;
    177 
    178     if (!gdk_pixbuf_get_has_alpha(pixbuf))
    179       continue;
    180 
    181     guchar* pixels = gdk_pixbuf_get_pixels(pixbuf);
    182     int rowstride = gdk_pixbuf_get_rowstride(pixbuf);
    183     int width = gdk_pixbuf_get_width(pixbuf);
    184     int height = gdk_pixbuf_get_height(pixbuf);
    185 
    186     if (width * 4 > rowstride) {
    187       NOTREACHED();
    188       continue;
    189     }
    190 
    191     for (int i = 0; i < height; ++i) {
    192       for (int j = 0; j < width; ++j) {
    193          guchar* pixel = &pixels[i * rowstride + j * 4];
    194          if (pixel[0] == 0xff && pixel[1] == 0xff && pixel[2] == 0xff) {
    195            pixel[3] = 0;
    196          }
    197       }
    198     }
    199   }
    200 }
    201 
    202 void NineBox::ContourWidget(GtkWidget* widget) const {
    203   int width = widget->allocation.width;
    204   int height = widget->allocation.height;
    205   int x1 = gdk_pixbuf_get_width(images_[0]);
    206   int x2 = width - gdk_pixbuf_get_width(images_[2]);
    207 
    208   // Paint the left and right sides.
    209   GdkBitmap* mask = gdk_pixmap_new(NULL, width, height, 1);
    210   gdk_pixbuf_render_threshold_alpha(images_[0], mask,
    211                                     0, 0,
    212                                     0, 0, -1, -1,
    213                                     1);
    214   gdk_pixbuf_render_threshold_alpha(images_[2], mask,
    215                                     0, 0,
    216                                     x2, 0, -1, -1,
    217                                     1);
    218 
    219   // Assume no transparency in the middle rectangle.
    220   cairo_t* cr = gdk_cairo_create(mask);
    221   cairo_rectangle(cr, x1, 0, x2 - x1, height);
    222   cairo_fill(cr);
    223   cairo_destroy(cr);
    224 
    225   // Mask the widget's window's shape.
    226   if (!base::i18n::IsRTL()) {
    227     gtk_widget_shape_combine_mask(widget, mask, 0, 0);
    228   } else {
    229     GdkBitmap* flipped_mask = gdk_pixmap_new(NULL, width, height, 1);
    230     cairo_t* flipped_cr = gdk_cairo_create(flipped_mask);
    231 
    232     // Clear the target bitmap.
    233     cairo_set_operator(flipped_cr, CAIRO_OPERATOR_CLEAR);
    234     cairo_paint(flipped_cr);
    235 
    236     // Apply flipping transformation.
    237     cairo_translate(flipped_cr, width, 0.0f);
    238     cairo_scale(flipped_cr, -1.0f, 1.0f);
    239 
    240     // Paint the source bitmap onto the target.
    241     cairo_set_operator(flipped_cr, CAIRO_OPERATOR_SOURCE);
    242     gdk_cairo_set_source_pixmap(flipped_cr, mask, 0, 0);
    243     cairo_paint(flipped_cr);
    244     cairo_destroy(flipped_cr);
    245 
    246     // Mask the widget.
    247     gtk_widget_shape_combine_mask(widget, flipped_mask, 0, 0);
    248     g_object_unref(flipped_mask);
    249   }
    250 
    251   g_object_unref(mask);
    252 }
    253