1 // Copyright 2014 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.
5 #include "ui/gfx/nine_image_painter.h"
9 #include "third_party/skia/include/core/SkPaint.h"
10 #include "third_party/skia/include/core/SkRect.h"
11 #include "third_party/skia/include/core/SkScalar.h"
12 #include "ui/gfx/canvas.h"
13 #include "ui/gfx/geometry/rect_conversions.h"
14 #include "ui/gfx/geometry/safe_integer_conversions.h"
15 #include "ui/gfx/image/image_skia_operations.h"
16 #include "ui/gfx/insets.h"
17 #include "ui/gfx/rect.h"
18 #include "ui/gfx/scoped_canvas.h"
19 #include "ui/gfx/skia_util.h"
25 // The following functions width and height of the image in pixels for the
26 // scale factor in the Canvas.
27 int ImageWidthInPixels(const ImageSkia& i, Canvas* c) {
28 return i.GetRepresentation(c->image_scale()).pixel_width();
31 int ImageHeightInPixels(const ImageSkia& i, Canvas* c) {
32 return i.GetRepresentation(c->image_scale()).pixel_height();
35 // Stretches the given image over the specified canvas area.
42 const SkPaint& paint) {
43 c->DrawImageIntInPixel(i, 0, 0, ImageWidthInPixels(i, c),
44 ImageHeightInPixels(i, c), x, y, w, h, false, paint);
49 NineImagePainter::NineImagePainter(const std::vector<ImageSkia>& images) {
50 DCHECK_EQ(arraysize(images_), images.size());
51 for (size_t i = 0; i < arraysize(images_); ++i)
52 images_[i] = images[i];
55 NineImagePainter::NineImagePainter(const ImageSkia& image,
56 const Insets& insets) {
57 DCHECK_GE(image.width(), insets.width());
58 DCHECK_GE(image.height(), insets.height());
60 // Extract subsets of the original image to match the |images_| format.
62 { 0, insets.left(), image.width() - insets.right(), image.width() };
64 { 0, insets.top(), image.height() - insets.bottom(), image.height() };
66 for (size_t j = 0; j < 3; ++j) {
67 for (size_t i = 0; i < 3; ++i) {
68 images_[i + j * 3] = ImageSkiaOperations::ExtractSubset(image,
69 Rect(x[i], y[j], x[i + 1] - x[i], y[j + 1] - y[j]));
74 NineImagePainter::~NineImagePainter() {
77 bool NineImagePainter::IsEmpty() const {
78 return images_[0].isNull();
81 Size NineImagePainter::GetMinimumSize() const {
82 return IsEmpty() ? Size() : Size(
83 images_[0].width() + images_[1].width() + images_[2].width(),
84 images_[0].height() + images_[3].height() + images_[6].height());
87 void NineImagePainter::Paint(Canvas* canvas, const Rect& bounds) {
88 // When no alpha value is specified, use default value of 100% opacity.
89 Paint(canvas, bounds, std::numeric_limits<uint8>::max());
92 void NineImagePainter::Paint(Canvas* canvas,
98 ScopedCanvas scoped_canvas(canvas);
99 canvas->Translate(bounds.OffsetFromOrigin());
101 // Get the current transform from the canvas and apply it to the logical
102 // bounds passed in. This will give us the pixel bounds which can be used
103 // to draw the images at the correct locations.
104 // We should not scale the bounds by the canvas->image_scale() as that can be
105 // different from the real scale in the canvas transform.
106 SkRect bounds_in_pixels_f;
107 if (!canvas->sk_canvas()->getTotalMatrix().mapRect(
108 &bounds_in_pixels_f, RectToSkRect(gfx::Rect(bounds.size()))))
109 return; // Invalid transform.
111 SkIRect bounds_in_pixels;
112 bounds_in_pixels_f.dround(&bounds_in_pixels);
114 SkMatrix matrix = canvas->sk_canvas()->getTotalMatrix();
115 matrix.setTranslateX(SkIntToScalar(bounds_in_pixels.x()));
116 matrix.setTranslateY(SkIntToScalar(bounds_in_pixels.y()));
117 canvas->sk_canvas()->setMatrix(matrix);
119 const int width_in_pixels = bounds_in_pixels.width();
120 const int height_in_pixels = bounds_in_pixels.height();
122 // In case the corners and edges don't all have the same width/height, we draw
123 // the center first, and extend it out in all directions to the edges of the
124 // images with the smallest widths/heights. This way there will be no
125 // unpainted areas, though some corners or edges might overlap the center.
126 int i0w = ImageWidthInPixels(images_[0], canvas);
127 int i2w = ImageWidthInPixels(images_[2], canvas);
128 int i3w = ImageWidthInPixels(images_[3], canvas);
129 int i5w = ImageWidthInPixels(images_[5], canvas);
130 int i6w = ImageWidthInPixels(images_[6], canvas);
131 int i8w = ImageWidthInPixels(images_[8], canvas);
133 int i4x = std::min(std::min(i0w, i3w), i6w);
134 int i4w = width_in_pixels - i4x - std::min(std::min(i2w, i5w), i8w);
136 int i0h = ImageHeightInPixels(images_[0], canvas);
137 int i1h = ImageHeightInPixels(images_[1], canvas);
138 int i2h = ImageHeightInPixels(images_[2], canvas);
139 int i6h = ImageHeightInPixels(images_[6], canvas);
140 int i7h = ImageHeightInPixels(images_[7], canvas);
141 int i8h = ImageHeightInPixels(images_[8], canvas);
143 int i4y = std::min(std::min(i0h, i1h), i2h);
144 int i4h = height_in_pixels - i4y - std::min(std::min(i6h, i7h), i8h);
147 paint.setAlpha(alpha);
149 if (!images_[4].isNull())
150 Fill(canvas, images_[4], i4x, i4y, i4w, i4h, paint);
151 canvas->DrawImageIntInPixel(images_[0], 0, 0, i0w, i0h,
152 0, 0, i0w, i0h, false, paint);
153 Fill(canvas, images_[1], i0w, 0, width_in_pixels - i0w - i2w, i1h, paint);
154 canvas->DrawImageIntInPixel(images_[2], 0, 0, i2w, i2h, width_in_pixels - i2w,
155 0, i2w, i2h, false, paint);
156 Fill(canvas, images_[3], 0, i0h, i3w, height_in_pixels - i0h - i6h, paint);
157 Fill(canvas, images_[5], width_in_pixels - i5w, i2h, i5w,
158 height_in_pixels - i2h - i8h, paint);
159 canvas->DrawImageIntInPixel(images_[6], 0, 0, i6w, i6h, 0,
160 height_in_pixels - i6h, i6w, i6h, false, paint);
161 Fill(canvas, images_[7], i6w, height_in_pixels - i7h,
162 width_in_pixels - i6w - i8w, i7h, paint);
163 canvas->DrawImageIntInPixel(images_[8], 0, 0, i8w, i8h, width_in_pixels - i8w,
164 height_in_pixels - i8h, i8w, i8h, false, paint);