chromium/src/third_party/blink/renderer/platform/graphics/skia/skia_utils.h - manifest_repos/chromium_src - Git at Google

 /*
  * Copyright (c) 2006,2007,2008, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
  * copyright notice, this list of conditions and the following disclaimer
  * in the documentation and/or other materials provided with the
  * distribution.
  *     * Neither the name of Google Inc. nor the names of its
  * contributors may be used to endorse or promote products derived from
  * this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 // All of the functions in this file should move to new homes and this file
 // should be deleted.

 #ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_SKIA_SKIA_UTILS_H_
 #define THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_SKIA_SKIA_UTILS_H_

 #include "cc/paint/paint_canvas.h"
 #include "third_party/blink/renderer/platform/graphics/graphics_types.h"
 #include "third_party/blink/renderer/platform/graphics/image.h"
 #include "third_party/blink/renderer/platform/platform_export.h"
 #include "third_party/blink/renderer/platform/transforms/affine_transform.h"
 #include "third_party/blink/renderer/platform/wtf/cross_thread_copier.h"
 #include "third_party/blink/renderer/platform/wtf/math_extras.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkData.h"
 #include "third_party/skia/include/core/SkPoint.h"
 #include "third_party/skia/include/core/SkRefCnt.h"
 #include "third_party/skia/include/core/SkScalar.h"

 namespace blink {
 class LayoutRect;

 /**** constants ****/

 enum {
   // Firefox limits width/height to 32767 pixels, but slows down dramatically
   // before it reaches that limit. We limit by area instead, giving us larger
   // maximum dimensions, in exchange for a smaller maximum canvas size.
   kMaxCanvasArea = 32768 * 8192,  // Maximum canvas area in CSS pixels

   // In Skia, we will also limit width/height to 65535.
   kMaxSkiaDim = 65535  // Maximum width/height in CSS pixels.
 };

 bool PLATFORM_EXPORT IsValidImageSize(const IntSize&);

 SkBlendMode PLATFORM_EXPORT
     WebCoreCompositeToSkiaComposite(CompositeOperator,
                                     BlendMode = BlendMode::kNormal);
 SkBlendMode PLATFORM_EXPORT WebCoreBlendModeToSkBlendMode(BlendMode);
 CompositeOperator PLATFORM_EXPORT CompositeOperatorFromSkBlendMode(SkBlendMode);
 BlendMode PLATFORM_EXPORT BlendModeFromSkBlendMode(SkBlendMode);

 // Multiply a color's alpha channel by an additional alpha factor where
 // alpha is in the range [0, 1].
 SkColor PLATFORM_EXPORT ScaleAlpha(SkColor, float);

 bool PLATFORM_EXPORT
 ApproximatelyEqualSkColorSpaces(sk_sp<SkColorSpace> src_color_space,
                                 sk_sp<SkColorSpace> dst_color_space);

 SkRect PLATFORM_EXPORT LayoutRectToSkRect(const blink::LayoutRect& rect);

 // Skia has problems when passed infinite, etc floats, filter them to 0.
 inline SkScalar WebCoreFloatToSkScalar(float f) {
   return SkFloatToScalar(std::isfinite(f) ? f : 0);
 }

 inline SkScalar WebCoreDoubleToSkScalar(double d) {
   return SkDoubleToScalar(std::isfinite(d) ? d : 0);
 }

 inline bool WebCoreFloatNearlyEqual(float a, float b) {
   return SkScalarNearlyEqual(WebCoreFloatToSkScalar(a),
                              WebCoreFloatToSkScalar(b));
 }

 inline SkPathFillType WebCoreWindRuleToSkFillType(WindRule rule) {
   return static_cast<SkPathFillType>(rule);
 }

 inline WindRule SkFillTypeToWindRule(SkPathFillType fill_type) {
   switch (fill_type) {
     case SkPathFillType::kWinding:
     case SkPathFillType::kEvenOdd:
       return static_cast<WindRule>(fill_type);
     default:
       NOTREACHED();
       break;
   }
   return RULE_NONZERO;
 }

 inline SkPoint FloatPointToSkPoint(const FloatPoint& point) {
   return SkPoint::Make(WebCoreFloatToSkScalar(point.X()),
                        WebCoreFloatToSkScalar(point.Y()));
 }

 SkMatrix PLATFORM_EXPORT AffineTransformToSkMatrix(const AffineTransform&);
 SkMatrix PLATFORM_EXPORT
 TransformationMatrixToSkMatrix(const TransformationMatrix&);

 bool NearlyIntegral(float value);

 InterpolationQuality ComputeInterpolationQuality(float src_width,
                                                  float src_height,
                                                  float dest_width,
                                                  float dest_height,
                                                  bool is_data_complete = true);

 // Technically, this is driven by the CSS/Canvas2D specs and unrelated to Skia.
 // It should probably live in the CSS layer, but the notion of a "blur radius"
 // leaks into platform/graphics currently (ideally we should only deal with
 // sigma at this level).
 // TODO(fmalita): find a better home for this helper.
 inline float BlurRadiusToStdDev(float radius) {
   DCHECK_GE(radius, 0);

   // Per spec, sigma is exactly half the blur radius:
   // https://www.w3.org/TR/css-backgrounds-3/#shadow-blur
   // https://html.spec.whatwg.org/C/#when-shadows-are-drawn
   return radius * 0.5f;
 }

 template <typename PrimitiveType>
 void DrawPlatformFocusRing(const PrimitiveType&,
                            cc::PaintCanvas*,
                            SkColor,
                            float width,
                            float border_radius);

 inline SkCanvas::SrcRectConstraint WebCoreClampingModeToSkiaRectConstraint(
     Image::ImageClampingMode clamp_mode) {
   return clamp_mode == Image::kClampImageToSourceRect
              ? SkCanvas::kStrict_SrcRectConstraint
              : SkCanvas::kFast_SrcRectConstraint;
 }

 // Attempts to allocate an SkData on the PartitionAlloc buffer partition.
 // If this fails (e.g. due to low memory), returns a null sk_sp<SkData> instead.
 // Otherwise, the returned buffer is guaranteed to be zero-filled.
 PLATFORM_EXPORT sk_sp<SkData> TryAllocateSkData(size_t size);

 // Skia's smart pointer APIs are preferable over their legacy raw pointer
 // counterparts.
 //
 // General guidelines
 //
 // When receiving ref counted objects from Skia:
 //
 //   1) Use sk_sp-based Skia factories if available (e.g. SkShader::MakeFoo()
 //      instead of SkShader::CreateFoo()).
 //   2) Use sk_sp<T> locals for all objects.
 //
 // When passing ref counted objects to Skia:
 //
 //   1) Use sk_sp-based Skia APIs when available (e.g.
 //      SkPaint::setShader(sk_sp<SkShader>) instead of
 //      SkPaint::setShader(SkShader*)).
 //   2) If object ownership is being passed to Skia, use std::move(sk_sp<T>).
 //
 // Example (creating a SkShader and setting it on SkPaint):
 //
 // a) ownership transferred
 //
 //     // using Skia smart pointer locals
 //     sk_sp<SkShader> shader = SkShader::MakeFoo(...);
 //     paint.setShader(std::move(shader));
 //
 //     // using no locals
 //     paint.setShader(SkShader::MakeFoo(...));
 //
 // b) shared ownership
 //
 //     sk_sp<SkShader> shader = SkShader::MakeFoo(...);
 //     paint.setShader(shader);

 }  // namespace blink

 namespace WTF {

 // We define CrossThreadCopier<SKBitMap> here because we cannot include skia
 // headers in platform/wtf.
 template <>
 struct CrossThreadCopier<SkBitmap> {
   STATIC_ONLY(CrossThreadCopier);

   using Type = SkBitmap;
   static SkBitmap Copy(const SkBitmap& bitmap) {
     CHECK(bitmap.isImmutable() || bitmap.isNull())
         << "Only immutable bitmaps can be transferred.";
     return bitmap;
   }
   static SkBitmap Copy(SkBitmap&& bitmap) {
     CHECK(bitmap.isImmutable() || bitmap.isNull())
         << "Only immutable bitmaps can be transferred.";
     return std::move(bitmap);
   }
 };

 }  // namespace WTF

 #endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_SKIA_SKIA_UTILS_H_
	/*
	* Copyright (c) 2006,2007,2008, Google Inc. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are
	* met:
	*
	* * Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* * Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following disclaimer
	* in the documentation and/or other materials provided with the
	* distribution.
	* * Neither the name of Google Inc. nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	// All of the functions in this file should move to new homes and this file
	// should be deleted.

	#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_SKIA_SKIA_UTILS_H_
	#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_SKIA_SKIA_UTILS_H_

	#include "cc/paint/paint_canvas.h"
	#include "third_party/blink/renderer/platform/graphics/graphics_types.h"
	#include "third_party/blink/renderer/platform/graphics/image.h"
	#include "third_party/blink/renderer/platform/platform_export.h"
	#include "third_party/blink/renderer/platform/transforms/affine_transform.h"
	#include "third_party/blink/renderer/platform/wtf/cross_thread_copier.h"
	#include "third_party/blink/renderer/platform/wtf/math_extras.h"
	#include "third_party/skia/include/core/SkBitmap.h"
	#include "third_party/skia/include/core/SkCanvas.h"
	#include "third_party/skia/include/core/SkColor.h"
	#include "third_party/skia/include/core/SkData.h"
	#include "third_party/skia/include/core/SkPoint.h"
	#include "third_party/skia/include/core/SkRefCnt.h"
	#include "third_party/skia/include/core/SkScalar.h"

	namespace blink {
	class LayoutRect;

	/** constants **/

	enum {
	// Firefox limits width/height to 32767 pixels, but slows down dramatically
	// before it reaches that limit. We limit by area instead, giving us larger
	// maximum dimensions, in exchange for a smaller maximum canvas size.
	kMaxCanvasArea = 32768 * 8192, // Maximum canvas area in CSS pixels

	// In Skia, we will also limit width/height to 65535.
	kMaxSkiaDim = 65535 // Maximum width/height in CSS pixels.
	};

	bool PLATFORM_EXPORT IsValidImageSize(const IntSize&);

	SkBlendMode PLATFORM_EXPORT
	WebCoreCompositeToSkiaComposite(CompositeOperator,
	BlendMode = BlendMode::kNormal);
	SkBlendMode PLATFORM_EXPORT WebCoreBlendModeToSkBlendMode(BlendMode);
	CompositeOperator PLATFORM_EXPORT CompositeOperatorFromSkBlendMode(SkBlendMode);
	BlendMode PLATFORM_EXPORT BlendModeFromSkBlendMode(SkBlendMode);

	// Multiply a color's alpha channel by an additional alpha factor where
	// alpha is in the range [0, 1].
	SkColor PLATFORM_EXPORT ScaleAlpha(SkColor, float);

	bool PLATFORM_EXPORT
	ApproximatelyEqualSkColorSpaces(sk_sp<SkColorSpace> src_color_space,
	sk_sp<SkColorSpace> dst_color_space);

	SkRect PLATFORM_EXPORT LayoutRectToSkRect(const blink::LayoutRect& rect);

	// Skia has problems when passed infinite, etc floats, filter them to 0.
	inline SkScalar WebCoreFloatToSkScalar(float f) {
	return SkFloatToScalar(std::isfinite(f) ? f : 0);
	}

	inline SkScalar WebCoreDoubleToSkScalar(double d) {
	return SkDoubleToScalar(std::isfinite(d) ? d : 0);
	}

	inline bool WebCoreFloatNearlyEqual(float a, float b) {
	return SkScalarNearlyEqual(WebCoreFloatToSkScalar(a),
	WebCoreFloatToSkScalar(b));
	}

	inline SkPathFillType WebCoreWindRuleToSkFillType(WindRule rule) {
	return static_cast<SkPathFillType>(rule);
	}

	inline WindRule SkFillTypeToWindRule(SkPathFillType fill_type) {
	switch (fill_type) {
	case SkPathFillType::kWinding:
	case SkPathFillType::kEvenOdd:
	return static_cast<WindRule>(fill_type);
	default:
	NOTREACHED();
	break;
	}
	return RULE_NONZERO;
	}

	inline SkPoint FloatPointToSkPoint(const FloatPoint& point) {
	return SkPoint::Make(WebCoreFloatToSkScalar(point.X()),
	WebCoreFloatToSkScalar(point.Y()));
	}

	SkMatrix PLATFORM_EXPORT AffineTransformToSkMatrix(const AffineTransform&);
	SkMatrix PLATFORM_EXPORT
	TransformationMatrixToSkMatrix(const TransformationMatrix&);

	bool NearlyIntegral(float value);

	InterpolationQuality ComputeInterpolationQuality(float src_width,
	float src_height,
	float dest_width,
	float dest_height,
	bool is_data_complete = true);

	// Technically, this is driven by the CSS/Canvas2D specs and unrelated to Skia.
	// It should probably live in the CSS layer, but the notion of a "blur radius"
	// leaks into platform/graphics currently (ideally we should only deal with
	// sigma at this level).
	// TODO(fmalita): find a better home for this helper.
	inline float BlurRadiusToStdDev(float radius) {
	DCHECK_GE(radius, 0);

	// Per spec, sigma is exactly half the blur radius:
	// https://www.w3.org/TR/css-backgrounds-3/#shadow-blur
	// https://html.spec.whatwg.org/C/#when-shadows-are-drawn
	return radius * 0.5f;
	}

	template <typename PrimitiveType>
	void DrawPlatformFocusRing(const PrimitiveType&,
	cc::PaintCanvas*,
	SkColor,
	float width,
	float border_radius);

	inline SkCanvas::SrcRectConstraint WebCoreClampingModeToSkiaRectConstraint(
	Image::ImageClampingMode clamp_mode) {
	return clamp_mode == Image::kClampImageToSourceRect
	? SkCanvas::kStrict_SrcRectConstraint
	: SkCanvas::kFast_SrcRectConstraint;
	}

	// Attempts to allocate an SkData on the PartitionAlloc buffer partition.
	// If this fails (e.g. due to low memory), returns a null sk_sp<SkData> instead.
	// Otherwise, the returned buffer is guaranteed to be zero-filled.
	PLATFORM_EXPORT sk_sp<SkData> TryAllocateSkData(size_t size);

	// Skia's smart pointer APIs are preferable over their legacy raw pointer
	// counterparts.
	//
	// General guidelines
	//
	// When receiving ref counted objects from Skia:
	//
	// 1) Use sk_sp-based Skia factories if available (e.g. SkShader::MakeFoo()
	// instead of SkShader::CreateFoo()).
	// 2) Use sk_sp<T> locals for all objects.
	//
	// When passing ref counted objects to Skia:
	//
	// 1) Use sk_sp-based Skia APIs when available (e.g.
	// SkPaint::setShader(sk_sp<SkShader>) instead of
	// SkPaint::setShader(SkShader*)).
	// 2) If object ownership is being passed to Skia, use std::move(sk_sp<T>).
	//
	// Example (creating a SkShader and setting it on SkPaint):
	//
	// a) ownership transferred
	//
	// // using Skia smart pointer locals
	// sk_sp<SkShader> shader = SkShader::MakeFoo(...);
	// paint.setShader(std::move(shader));
	//
	// // using no locals
	// paint.setShader(SkShader::MakeFoo(...));
	//
	// b) shared ownership
	//
	// sk_sp<SkShader> shader = SkShader::MakeFoo(...);
	// paint.setShader(shader);

	} // namespace blink

	namespace WTF {

	// We define CrossThreadCopier<SKBitMap> here because we cannot include skia
	// headers in platform/wtf.
	template <>
	struct CrossThreadCopier<SkBitmap> {
	STATIC_ONLY(CrossThreadCopier);

	using Type = SkBitmap;
	static SkBitmap Copy(const SkBitmap& bitmap) {
	CHECK(bitmap.isImmutable() \|\| bitmap.isNull())
	<< "Only immutable bitmaps can be transferred.";
	return bitmap;
	}
	static SkBitmap Copy(SkBitmap&& bitmap) {
	CHECK(bitmap.isImmutable() \|\| bitmap.isNull())
	<< "Only immutable bitmaps can be transferred.";
	return std::move(bitmap);
	}
	};

	} // namespace WTF

	#endif // THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_SKIA_SKIA_UTILS_H_