1 // Copyright (c) 2012 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/canvas.h"
10 #include "base/i18n/rtl.h"
11 #include "base/logging.h"
12 #include "third_party/skia/include/core/SkBitmap.h"
13 #include "third_party/skia/include/effects/SkGradientShader.h"
14 #include "ui/gfx/font_list.h"
15 #include "ui/gfx/rect.h"
16 #include "ui/gfx/size_conversions.h"
17 #include "ui/gfx/skia_util.h"
18 #include "ui/gfx/transform.h"
21 #include "ui/gfx/canvas_skia_paint.h"
26 Canvas::Canvas(const Size& size, float image_scale, bool is_opaque)
27 : image_scale_(image_scale),
29 Size pixel_size = ToCeiledSize(ScaleSize(size, image_scale));
30 owned_canvas_ = skia::AdoptRef(skia::CreatePlatformCanvas(pixel_size.width(),
33 canvas_ = owned_canvas_.get();
34 #if defined(OS_WIN) || defined(OS_MACOSX)
35 // skia::PlatformCanvas instances are initialized to 0 by Cairo on Linux, but
36 // uninitialized on Win and Mac.
38 owned_canvas_->clear(SkColorSetARGB(0, 0, 0, 0));
41 SkScalar scale_scalar = SkFloatToScalar(image_scale);
42 canvas_->scale(scale_scalar, scale_scalar);
45 Canvas::Canvas(const ImageSkiaRep& image_rep, bool is_opaque)
46 : image_scale_(image_rep.scale()),
47 owned_canvas_(skia::AdoptRef(
48 skia::CreatePlatformCanvas(image_rep.pixel_width(),
49 image_rep.pixel_height(),
51 canvas_(owned_canvas_.get()) {
52 SkScalar scale_scalar = SkFloatToScalar(image_scale_);
53 canvas_->scale(scale_scalar, scale_scalar);
54 DrawImageInt(ImageSkia(image_rep), 0, 0);
59 owned_canvas_(skia::AdoptRef(skia::CreatePlatformCanvas(0, 0, false))),
60 canvas_(owned_canvas_.get()) {
67 Canvas* Canvas::CreateCanvasWithoutScaling(SkCanvas* canvas,
69 return new Canvas(canvas, image_scale);
72 void Canvas::RecreateBackingCanvas(const Size& size,
75 image_scale_ = image_scale;
76 Size pixel_size = ToFlooredSize(ScaleSize(size, image_scale));
77 owned_canvas_ = skia::AdoptRef(skia::CreatePlatformCanvas(pixel_size.width(),
80 canvas_ = owned_canvas_.get();
81 SkScalar scale_scalar = SkFloatToScalar(image_scale);
82 canvas_->scale(scale_scalar, scale_scalar);
86 void Canvas::SizeStringInt(const base::string16& text,
87 const FontList& font_list,
92 float fractional_width = *width;
93 float factional_height = *height;
94 SizeStringFloat(text, font_list, &fractional_width,
95 &factional_height, line_height, flags);
96 *width = std::ceil(fractional_width);
97 *height = std::ceil(factional_height);
101 int Canvas::GetStringWidth(const base::string16& text,
102 const FontList& font_list) {
103 int width = 0, height = 0;
104 SizeStringInt(text, font_list, &width, &height, 0, NO_ELLIPSIS);
109 float Canvas::GetStringWidthF(const base::string16& text,
110 const FontList& font_list) {
111 float width = 0, height = 0;
112 SizeStringFloat(text, font_list, &width, &height, 0, NO_ELLIPSIS);
117 int Canvas::DefaultCanvasTextAlignment() {
118 return base::i18n::IsRTL() ? TEXT_ALIGN_RIGHT : TEXT_ALIGN_LEFT;
121 ImageSkiaRep Canvas::ExtractImageRep() const {
122 // Make a bitmap to return, and a canvas to draw into it. We don't just want
123 // to call extractSubset or the copy constructor, since we want an actual copy
125 const SkISize size = canvas_->getDeviceSize();
127 result.allocN32Pixels(size.width(), size.height());
129 canvas_->readPixels(&result, 0, 0);
130 return ImageSkiaRep(result, image_scale_);
133 void Canvas::DrawDashedRect(const Rect& rect, SkColor color) {
134 // Create a 2D bitmap containing alternating on/off pixels - we do this
135 // so that you never get two pixels of the same color around the edges
136 // of the focus rect (this may mean that opposing edges of the rect may
137 // have a dot pattern out of phase to each other).
138 static SkColor last_color;
139 static SkBitmap* dots = NULL;
140 if (!dots || last_color != color) {
147 dots->allocN32Pixels(col_pixels, row_pixels);
148 dots->eraseARGB(0, 0, 0, 0);
150 uint32_t* dot = dots->getAddr32(0, 0);
151 for (int i = 0; i < row_pixels; i++) {
152 for (int u = 0; u < col_pixels; u++) {
153 if ((u % 2 + i % 2) % 2 != 0) {
154 dot[i * row_pixels + u] = color;
160 // Make a shader for the bitmap with an origin of the box we'll draw. This
161 // shader is refcounted and will have an initial refcount of 1.
162 skia::RefPtr<SkShader> shader = skia::AdoptRef(
163 SkShader::CreateBitmapShader(
164 *dots, SkShader::kRepeat_TileMode, SkShader::kRepeat_TileMode));
165 // Assign the shader to the paint & release our reference. The paint will
166 // now own the shader and the shader will be destroyed when the paint goes
169 paint.setShader(shader.get());
171 DrawRect(Rect(rect.x(), rect.y(), rect.width(), 1), paint);
172 DrawRect(Rect(rect.x(), rect.y() + rect.height() - 1, rect.width(), 1),
174 DrawRect(Rect(rect.x(), rect.y(), 1, rect.height()), paint);
175 DrawRect(Rect(rect.x() + rect.width() - 1, rect.y(), 1, rect.height()),
179 void Canvas::Save() {
183 void Canvas::SaveLayerAlpha(uint8 alpha) {
184 canvas_->saveLayerAlpha(NULL, alpha);
188 void Canvas::SaveLayerAlpha(uint8 alpha, const Rect& layer_bounds) {
189 SkRect bounds(RectToSkRect(layer_bounds));
190 canvas_->saveLayerAlpha(&bounds, alpha);
193 void Canvas::Restore() {
197 void Canvas::ClipRect(const Rect& rect) {
198 canvas_->clipRect(RectToSkRect(rect));
201 void Canvas::ClipPath(const SkPath& path) {
202 canvas_->clipPath(path);
205 bool Canvas::IsClipEmpty() const {
206 return canvas_->isClipEmpty();
209 bool Canvas::GetClipBounds(Rect* bounds) {
211 bool has_non_empty_clip = canvas_->getClipBounds(&out);
212 bounds->SetRect(out.left(), out.top(), out.width(), out.height());
213 return has_non_empty_clip;
216 void Canvas::Translate(const Vector2d& offset) {
217 canvas_->translate(SkIntToScalar(offset.x()), SkIntToScalar(offset.y()));
220 void Canvas::Scale(int x_scale, int y_scale) {
221 canvas_->scale(SkIntToScalar(x_scale), SkIntToScalar(y_scale));
224 void Canvas::DrawColor(SkColor color) {
225 DrawColor(color, SkXfermode::kSrcOver_Mode);
228 void Canvas::DrawColor(SkColor color, SkXfermode::Mode mode) {
229 canvas_->drawColor(color, mode);
232 void Canvas::FillRect(const Rect& rect, SkColor color) {
233 FillRect(rect, color, SkXfermode::kSrcOver_Mode);
236 void Canvas::FillRect(const Rect& rect,
238 SkXfermode::Mode mode) {
240 paint.setColor(color);
241 paint.setStyle(SkPaint::kFill_Style);
242 paint.setXfermodeMode(mode);
243 DrawRect(rect, paint);
246 void Canvas::DrawRect(const Rect& rect, SkColor color) {
247 DrawRect(rect, color, SkXfermode::kSrcOver_Mode);
250 void Canvas::DrawRect(const Rect& rect,
252 SkXfermode::Mode mode) {
254 paint.setColor(color);
255 paint.setStyle(SkPaint::kStroke_Style);
256 // Set a stroke width of 0, which will put us down the stroke rect path. If
257 // we set a stroke width of 1, for example, this will internally create a
258 // path and fill it, which causes problems near the edge of the canvas.
259 paint.setStrokeWidth(SkIntToScalar(0));
260 paint.setXfermodeMode(mode);
262 DrawRect(rect, paint);
265 void Canvas::DrawRect(const Rect& rect, const SkPaint& paint) {
266 canvas_->drawIRect(RectToSkIRect(rect), paint);
269 void Canvas::DrawPoint(const Point& p1, const SkPaint& paint) {
270 canvas_->drawPoint(SkIntToScalar(p1.x()), SkIntToScalar(p1.y()), paint);
273 void Canvas::DrawLine(const Point& p1, const Point& p2, SkColor color) {
275 paint.setColor(color);
276 paint.setStrokeWidth(SkIntToScalar(1));
277 DrawLine(p1, p2, paint);
280 void Canvas::DrawLine(const Point& p1, const Point& p2, const SkPaint& paint) {
281 canvas_->drawLine(SkIntToScalar(p1.x()), SkIntToScalar(p1.y()),
282 SkIntToScalar(p2.x()), SkIntToScalar(p2.y()), paint);
285 void Canvas::DrawCircle(const Point& center_point,
287 const SkPaint& paint) {
288 canvas_->drawCircle(SkIntToScalar(center_point.x()),
289 SkIntToScalar(center_point.y()), SkIntToScalar(radius), paint);
292 void Canvas::DrawRoundRect(const Rect& rect,
294 const SkPaint& paint) {
295 canvas_->drawRoundRect(RectToSkRect(rect), SkIntToScalar(radius),
296 SkIntToScalar(radius), paint);
299 void Canvas::DrawPath(const SkPath& path, const SkPaint& paint) {
300 canvas_->drawPath(path, paint);
303 void Canvas::DrawFocusRect(const Rect& rect) {
304 DrawDashedRect(rect, SK_ColorGRAY);
307 void Canvas::DrawSolidFocusRect(const Rect& rect, SkColor color) {
309 paint.setColor(color);
310 paint.setStrokeWidth(SkIntToScalar(1));
311 // Note: We cannot use DrawRect since it would create a path and fill it which
312 // would cause problems near the edge of the canvas.
313 int x1 = std::min(rect.x(), rect.right());
314 int x2 = std::max(rect.x(), rect.right());
315 int y1 = std::min(rect.y(), rect.bottom());
316 int y2 = std::max(rect.y(), rect.bottom());
317 DrawLine(Point(x1, y1), Point(x2, y1), paint);
318 DrawLine(Point(x1, y2), Point(x2, y2), paint);
319 DrawLine(Point(x1, y1), Point(x1, y2), paint);
320 DrawLine(Point(x2, y1), Point(x2, y2 + 1), paint);
323 void Canvas::DrawImageInt(const ImageSkia& image, int x, int y) {
325 DrawImageInt(image, x, y, paint);
328 void Canvas::DrawImageInt(const ImageSkia& image, int x, int y, uint8 a) {
331 DrawImageInt(image, x, y, paint);
334 void Canvas::DrawImageInt(const ImageSkia& image,
337 const SkPaint& paint) {
338 const ImageSkiaRep& image_rep = GetImageRepToPaint(image);
339 if (image_rep.is_null())
341 const SkBitmap& bitmap = image_rep.sk_bitmap();
342 float bitmap_scale = image_rep.scale();
345 canvas_->scale(SkFloatToScalar(1.0f / bitmap_scale),
346 SkFloatToScalar(1.0f / bitmap_scale));
347 canvas_->drawBitmap(bitmap,
348 SkFloatToScalar(x * bitmap_scale),
349 SkFloatToScalar(y * bitmap_scale),
354 void Canvas::DrawImageInt(const ImageSkia& image,
365 DrawImageInt(image, src_x, src_y, src_w, src_h, dest_x, dest_y,
366 dest_w, dest_h, filter, p);
369 void Canvas::DrawImageInt(const ImageSkia& image,
379 const SkPaint& paint) {
380 DrawImageIntHelper(image, src_x, src_y, src_w, src_h, dest_x, dest_y, dest_w,
381 dest_h, filter, paint, image_scale_, false);
384 void Canvas::DrawImageIntInPixel(const ImageSkia& image,
394 const SkPaint& paint) {
396 // 1. Translate the destination rectangle using the current translation
397 // values from the SkCanvas matrix stack.
398 // 2. Save the current state of the canvas.
399 // 3. Reset the scales and the translation values in the SkCanvas matrix
401 // 4. Set the scale in gfx::Canvas instance to 1.0, 1.0.
402 // 5. Draw the image.
403 // 6. Restore the state of the canvas and the SkCanvas matrix stack.
404 SkMatrix matrix = canvas_->getTotalMatrix();
406 SkRect destination_rect;
407 destination_rect.set(SkIntToScalar(dest_x),
408 SkIntToScalar(dest_y),
409 SkIntToScalar(dest_x + dest_w),
410 SkIntToScalar(dest_y + dest_h));
411 matrix.setScaleX(1.0f);
412 matrix.setScaleY(1.0f);
413 matrix.mapRect(&destination_rect, destination_rect);
417 // The destination is now in pixel values. No need for further translation.
418 matrix.setTranslate(0, 0);
419 canvas_->setMatrix(matrix);
421 DrawImageIntHelper(image,
426 SkScalarRoundToInt(destination_rect.x()),
427 SkScalarRoundToInt(destination_rect.y()),
428 SkScalarRoundToInt(destination_rect.width()),
429 SkScalarRoundToInt(destination_rect.height()),
435 // Restore the state of the canvas.
439 void Canvas::DrawImageInPath(const ImageSkia& image,
443 const SkPaint& paint) {
444 const ImageSkiaRep& image_rep = GetImageRepToPaint(image);
445 if (image_rep.is_null())
449 matrix.setTranslate(SkIntToScalar(x), SkIntToScalar(y));
450 skia::RefPtr<SkShader> shader = CreateImageRepShader(
452 SkShader::kRepeat_TileMode,
456 p.setShader(shader.get());
457 canvas_->drawPath(path, p);
460 void Canvas::DrawStringRect(const base::string16& text,
461 const FontList& font_list,
463 const Rect& display_rect) {
464 DrawStringRectWithFlags(text, font_list, color, display_rect,
465 DefaultCanvasTextAlignment());
468 void Canvas::DrawStringRectWithFlags(const base::string16& text,
469 const FontList& font_list,
471 const Rect& display_rect,
473 DrawStringRectWithShadows(text, font_list, color, display_rect, 0, flags,
477 void Canvas::TileImageInt(const ImageSkia& image,
482 TileImageInt(image, 0, 0, x, y, w, h);
485 void Canvas::TileImageInt(const ImageSkia& image,
492 TileImageInt(image, src_x, src_y, 1.0f, 1.0f, dest_x, dest_y, w, h);
495 void Canvas::TileImageInt(const ImageSkia& image,
504 if (!IntersectsClipRectInt(dest_x, dest_y, w, h))
507 const ImageSkiaRep& image_rep = GetImageRepToPaint(
508 image, image_scale_, tile_scale_x, tile_scale_y);
509 if (image_rep.is_null())
512 SkMatrix shader_scale;
513 shader_scale.setScale(SkFloatToScalar(tile_scale_x),
514 SkFloatToScalar(tile_scale_y));
515 shader_scale.preTranslate(SkIntToScalar(-src_x), SkIntToScalar(-src_y));
516 shader_scale.postTranslate(SkIntToScalar(dest_x), SkIntToScalar(dest_y));
518 skia::RefPtr<SkShader> shader = CreateImageRepShader(
520 SkShader::kRepeat_TileMode,
524 paint.setShader(shader.get());
525 paint.setXfermodeMode(SkXfermode::kSrcOver_Mode);
527 SkRect dest_rect = { SkIntToScalar(dest_x),
528 SkIntToScalar(dest_y),
529 SkIntToScalar(dest_x + w),
530 SkIntToScalar(dest_y + h) };
531 canvas_->drawRect(dest_rect, paint);
534 NativeDrawingContext Canvas::BeginPlatformPaint() {
535 return skia::BeginPlatformPaint(canvas_);
538 void Canvas::EndPlatformPaint() {
539 skia::EndPlatformPaint(canvas_);
542 void Canvas::Transform(const gfx::Transform& transform) {
543 canvas_->concat(transform.matrix());
546 Canvas::Canvas(SkCanvas* canvas, float image_scale)
547 : image_scale_(image_scale),
553 bool Canvas::IntersectsClipRectInt(int x, int y, int w, int h) {
555 return canvas_->getClipBounds(&clip) &&
556 clip.intersect(SkIntToScalar(x), SkIntToScalar(y), SkIntToScalar(x + w),
557 SkIntToScalar(y + h));
560 bool Canvas::IntersectsClipRect(const Rect& rect) {
561 return IntersectsClipRectInt(rect.x(), rect.y(),
562 rect.width(), rect.height());
565 const ImageSkiaRep& Canvas::GetImageRepToPaint(const ImageSkia& image) const {
566 return GetImageRepToPaint(image, image_scale_, 1.0f, 1.0f);
569 const ImageSkiaRep& Canvas::GetImageRepToPaint(
570 const ImageSkia& image,
572 float user_additional_scale_x,
573 float user_additional_scale_y) const {
574 const ImageSkiaRep& image_rep = image.GetRepresentation(image_scale);
576 if (!image_rep.is_null()) {
577 SkMatrix m = canvas_->getTotalMatrix();
578 float scale_x = SkScalarToFloat(SkScalarAbs(m.getScaleX())) *
579 user_additional_scale_x;
580 float scale_y = SkScalarToFloat(SkScalarAbs(m.getScaleY())) *
581 user_additional_scale_y;
583 float bitmap_scale = image_rep.scale();
584 if (scale_x < bitmap_scale || scale_y < bitmap_scale)
585 const_cast<SkBitmap&>(image_rep.sk_bitmap()).buildMipMap();
591 void Canvas::DrawImageIntHelper(const ImageSkia& image,
601 const SkPaint& paint,
604 DLOG_ASSERT(src_x + src_w < std::numeric_limits<int16_t>::max() &&
605 src_y + src_h < std::numeric_limits<int16_t>::max());
606 if (src_w <= 0 || src_h <= 0) {
607 NOTREACHED() << "Attempting to draw bitmap from an empty rect!";
611 if (!IntersectsClipRectInt(dest_x, dest_y, dest_w, dest_h))
614 float user_scale_x = static_cast<float>(dest_w) / src_w;
615 float user_scale_y = static_cast<float>(dest_h) / src_h;
617 const ImageSkiaRep& image_rep = GetImageRepToPaint(image,
618 image_scale, user_scale_x, user_scale_y);
619 if (image_rep.is_null())
622 SkRect dest_rect = { SkIntToScalar(dest_x),
623 SkIntToScalar(dest_y),
624 SkIntToScalar(dest_x + dest_w),
625 SkIntToScalar(dest_y + dest_h) };
627 if (src_w == dest_w && src_h == dest_h &&
628 user_scale_x == 1.0f && user_scale_y == 1.0f &&
629 image_rep.scale() == 1.0f && !pixel) {
630 // Workaround for apparent bug in Skia that causes image to occasionally
632 SkIRect src_rect = { src_x, src_y, src_x + src_w, src_y + src_h };
633 const SkBitmap& bitmap = image_rep.sk_bitmap();
634 canvas_->drawBitmapRect(bitmap, &src_rect, dest_rect, &paint);
638 // Make a bitmap shader that contains the bitmap we want to draw. This is
639 // basically what SkCanvas.drawBitmap does internally, but it gives us
640 // more control over quality and will use the mipmap in the source image if
641 // it has one, whereas drawBitmap won't.
642 SkMatrix shader_scale;
643 shader_scale.setScale(SkFloatToScalar(user_scale_x),
644 SkFloatToScalar(user_scale_y));
645 shader_scale.preTranslate(SkIntToScalar(-src_x), SkIntToScalar(-src_y));
646 shader_scale.postTranslate(SkIntToScalar(dest_x), SkIntToScalar(dest_y));
648 skia::RefPtr<SkShader> shader = CreateImageRepShaderForScale(
650 SkShader::kRepeat_TileMode,
652 pixel ? 1.0f : image_rep.scale());
654 // Set up our paint to use the shader & release our reference (now just owned
657 p.setFilterBitmap(filter);
658 p.setShader(shader.get());
660 // The rect will be filled by the bitmap.
661 canvas_->drawRect(dest_rect, p);