include/core/SkPixmap.h - skia - Git at Google

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #ifndef SkPixmap_DEFINED
 #define SkPixmap_DEFINED

 #include "SkColor.h"
 #include "SkFilterQuality.h"
 #include "SkImageInfo.h"

 class SkColorTable;
 class SkData;
 struct SkMask;

 /**
  *  Pairs SkImageInfo with actual pixels and rowbytes. This class does not try to manage the
  *  lifetime of the pixel memory (nor the colortable if provided).
  */
 class SK_API SkPixmap {
 public:
     SkPixmap()
         : fPixels(NULL), fCTable(NULL), fRowBytes(0), fInfo(SkImageInfo::MakeUnknown(0, 0))
     {}

     SkPixmap(const SkImageInfo& info, const void* addr, size_t rowBytes,
              SkColorTable* ctable = NULL)
         : fPixels(addr), fCTable(ctable), fRowBytes(rowBytes), fInfo(info)
     {
         if (kIndex_8_SkColorType == info.colorType()) {
             SkASSERT(ctable);
         } else {
             SkASSERT(NULL == ctable);
         }
     }

     void reset();
     void reset(const SkImageInfo& info, const void* addr, size_t rowBytes,
                SkColorTable* ctable = NULL);
     void reset(const SkImageInfo& info) {
         this->reset(info, NULL, 0, NULL);
     }

     // overrides the colorspace in the SkImageInfo of the pixmap
     void setColorSpace(sk_sp<SkColorSpace>);

     /**
      *  If supported, set this pixmap to point to the pixels in the specified mask and return true.
      *  On failure, return false and set this pixmap to empty.
      */
     bool SK_WARN_UNUSED_RESULT reset(const SkMask&);

     /**
      *  Computes the intersection of area and this pixmap. If that intersection is non-empty,
      *  set subset to that intersection and return true.
      *
      *  On failure, return false and ignore the subset parameter.
      */
     bool SK_WARN_UNUSED_RESULT extractSubset(SkPixmap* subset, const SkIRect& area) const;

     const SkImageInfo& info() const { return fInfo; }
     size_t rowBytes() const { return fRowBytes; }
     const void* addr() const { return fPixels; }
     SkColorTable* ctable() const { return fCTable; }

     int width() const { return fInfo.width(); }
     int height() const { return fInfo.height(); }
     SkColorType colorType() const { return fInfo.colorType(); }
     SkAlphaType alphaType() const { return fInfo.alphaType(); }
     SkColorSpace* colorSpace() const { return fInfo.colorSpace(); }
     bool isOpaque() const { return fInfo.isOpaque(); }

     SkIRect bounds() const { return SkIRect::MakeWH(this->width(), this->height()); }

     /**
      *  Return the rowbytes expressed as a number of pixels (like width and height).
      */
     int rowBytesAsPixels() const { return int(fRowBytes >> this->shiftPerPixel()); }

     /**
      *  Return the shift amount per pixel (i.e. 0 for 1-byte per pixel, 1 for 2-bytes per pixel
      *  colortypes, 2 for 4-bytes per pixel colortypes). Return 0 for kUnknown_SkColorType.
      */
     int shiftPerPixel() const { return fInfo.shiftPerPixel(); }

     uint64_t getSize64() const { return sk_64_mul(fInfo.height(), fRowBytes); }
     uint64_t getSafeSize64() const { return fInfo.getSafeSize64(fRowBytes); }
     size_t getSafeSize() const { return fInfo.getSafeSize(fRowBytes); }

     /**
      *  This will brute-force return true if all of the pixels in the pixmap
      *  are opaque. If there are no pixels, or encounters an error, returns false.
      */
     bool computeIsOpaque() const;

     /**
      *  Converts the pixel at the specified coordinate to an unpremultiplied
      *  SkColor. Note: this ignores any SkColorSpace information, and may return
      *  lower precision data than is actually in the pixel. Alpha only
      *  colortypes (e.g. kAlpha_8_SkColorType) return black with the appropriate
      *  alpha set.  The value is undefined for kUnknown_SkColorType or if x or y
      *  are out of bounds, or if the pixtap does not have any pixels.
      */
     SkColor getColor(int x, int y) const;

     const void* addr(int x, int y) const {
         return (const char*)fPixels + fInfo.computeOffset(x, y, fRowBytes);
     }
     const uint8_t* addr8() const {
         SkASSERT(1 == SkColorTypeBytesPerPixel(fInfo.colorType()));
         return reinterpret_cast<const uint8_t*>(fPixels);
     }
     const uint16_t* addr16() const {
         SkASSERT(2 == SkColorTypeBytesPerPixel(fInfo.colorType()));
         return reinterpret_cast<const uint16_t*>(fPixels);
     }
     const uint32_t* addr32() const {
         SkASSERT(4 == SkColorTypeBytesPerPixel(fInfo.colorType()));
         return reinterpret_cast<const uint32_t*>(fPixels);
     }
     const uint64_t* addr64() const {
         SkASSERT(8 == SkColorTypeBytesPerPixel(fInfo.colorType()));
         return reinterpret_cast<const uint64_t*>(fPixels);
     }
     const uint16_t* addrF16() const {
         SkASSERT(8 == SkColorTypeBytesPerPixel(fInfo.colorType()));
         SkASSERT(kRGBA_F16_SkColorType == fInfo.colorType());
         return reinterpret_cast<const uint16_t*>(fPixels);
     }

     // Offset by the specified x,y coordinates

     const uint8_t* addr8(int x, int y) const {
         SkASSERT((unsigned)x < (unsigned)fInfo.width());
         SkASSERT((unsigned)y < (unsigned)fInfo.height());
         return (const uint8_t*)((const char*)this->addr8() + y * fRowBytes + (x << 0));
     }
     const uint16_t* addr16(int x, int y) const {
         SkASSERT((unsigned)x < (unsigned)fInfo.width());
         SkASSERT((unsigned)y < (unsigned)fInfo.height());
         return (const uint16_t*)((const char*)this->addr16() + y * fRowBytes + (x << 1));
     }
     const uint32_t* addr32(int x, int y) const {
         SkASSERT((unsigned)x < (unsigned)fInfo.width());
         SkASSERT((unsigned)y < (unsigned)fInfo.height());
         return (const uint32_t*)((const char*)this->addr32() + y * fRowBytes + (x << 2));
     }
     const uint64_t* addr64(int x, int y) const {
         SkASSERT((unsigned)x < (unsigned)fInfo.width());
         SkASSERT((unsigned)y < (unsigned)fInfo.height());
         return (const uint64_t*)((const char*)this->addr64() + y * fRowBytes + (x << 3));
     }
     const uint16_t* addrF16(int x, int y) const {
         SkASSERT(kRGBA_F16_SkColorType == fInfo.colorType());
         return reinterpret_cast<const uint16_t*>(this->addr64(x, y));
     }

     // Writable versions

     void* writable_addr() const { return const_cast<void*>(fPixels); }
     void* writable_addr(int x, int y) const {
         return const_cast<void*>(this->addr(x, y));
     }
     uint8_t* writable_addr8(int x, int y) const {
         return const_cast<uint8_t*>(this->addr8(x, y));
     }
     uint16_t* writable_addr16(int x, int y) const {
         return const_cast<uint16_t*>(this->addr16(x, y));
     }
     uint32_t* writable_addr32(int x, int y) const {
         return const_cast<uint32_t*>(this->addr32(x, y));
     }
     uint64_t* writable_addr64(int x, int y) const {
         return const_cast<uint64_t*>(this->addr64(x, y));
     }
     uint16_t* writable_addrF16(int x, int y) const {
         return reinterpret_cast<uint16_t*>(writable_addr64(x, y));
     }

     // copy methods

     bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
                     int srcX, int srcY) const;
     bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes) const {
         return this->readPixels(dstInfo, dstPixels, dstRowBytes, 0, 0);
     }
     bool readPixels(const SkPixmap& dst, int srcX, int srcY) const {
         return this->readPixels(dst.info(), dst.writable_addr(), dst.rowBytes(), srcX, srcY);
     }
     bool readPixels(const SkPixmap& dst) const {
         return this->readPixels(dst.info(), dst.writable_addr(), dst.rowBytes(), 0, 0);
     }

     /**
      *  Copy the pixels from this pixmap into the dst pixmap, converting as needed into dst's
      *  colortype/alphatype. If the conversion cannot be performed, false is returned.
      *
      *  If dst's dimensions differ from the src dimension, the image will be scaled, applying the
      *  specified filter-quality.
      */
     bool scalePixels(const SkPixmap& dst, SkFilterQuality) const;

     /**
      *  Returns true if pixels were written to (e.g. if colorType is kUnknown_SkColorType, this
      *  will return false). If subset does not intersect the bounds of this pixmap, returns false.
      */
     bool erase(SkColor, const SkIRect& subset) const;

     bool erase(SkColor color) const { return this->erase(color, this->bounds()); }
     bool erase(const SkColor4f&, const SkIRect* subset = nullptr) const;

 private:
     const void*     fPixels;
     SkColorTable*   fCTable;
     size_t          fRowBytes;
     SkImageInfo     fInfo;
 };

 #endif
	/*
	* Copyright 2015 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#ifndef SkPixmap_DEFINED
	#define SkPixmap_DEFINED

	#include "SkColor.h"
	#include "SkFilterQuality.h"
	#include "SkImageInfo.h"

	class SkColorTable;
	class SkData;
	struct SkMask;

	/**
	* Pairs SkImageInfo with actual pixels and rowbytes. This class does not try to manage the
	* lifetime of the pixel memory (nor the colortable if provided).
	*/
	class SK_API SkPixmap {
	public:
	SkPixmap()
	: fPixels(NULL), fCTable(NULL), fRowBytes(0), fInfo(SkImageInfo::MakeUnknown(0, 0))
	{}

	SkPixmap(const SkImageInfo& info, const void* addr, size_t rowBytes,
	SkColorTable* ctable = NULL)
	: fPixels(addr), fCTable(ctable), fRowBytes(rowBytes), fInfo(info)
	{
	if (kIndex_8_SkColorType == info.colorType()) {
	SkASSERT(ctable);
	} else {
	SkASSERT(NULL == ctable);
	}
	}

	void reset();
	void reset(const SkImageInfo& info, const void* addr, size_t rowBytes,
	SkColorTable* ctable = NULL);
	void reset(const SkImageInfo& info) {
	this->reset(info, NULL, 0, NULL);
	}

	// overrides the colorspace in the SkImageInfo of the pixmap
	void setColorSpace(sk_sp<SkColorSpace>);

	/**
	* If supported, set this pixmap to point to the pixels in the specified mask and return true.
	* On failure, return false and set this pixmap to empty.
	*/
	bool SK_WARN_UNUSED_RESULT reset(const SkMask&);

	/**
	* Computes the intersection of area and this pixmap. If that intersection is non-empty,
	* set subset to that intersection and return true.
	*
	* On failure, return false and ignore the subset parameter.
	*/
	bool SK_WARN_UNUSED_RESULT extractSubset(SkPixmap* subset, const SkIRect& area) const;

	const SkImageInfo& info() const { return fInfo; }
	size_t rowBytes() const { return fRowBytes; }
	const void* addr() const { return fPixels; }
	SkColorTable* ctable() const { return fCTable; }

	int width() const { return fInfo.width(); }
	int height() const { return fInfo.height(); }
	SkColorType colorType() const { return fInfo.colorType(); }
	SkAlphaType alphaType() const { return fInfo.alphaType(); }
	SkColorSpace* colorSpace() const { return fInfo.colorSpace(); }
	bool isOpaque() const { return fInfo.isOpaque(); }

	SkIRect bounds() const { return SkIRect::MakeWH(this->width(), this->height()); }

	/**
	* Return the rowbytes expressed as a number of pixels (like width and height).
	*/
	int rowBytesAsPixels() const { return int(fRowBytes >> this->shiftPerPixel()); }

	/**
	* Return the shift amount per pixel (i.e. 0 for 1-byte per pixel, 1 for 2-bytes per pixel
	* colortypes, 2 for 4-bytes per pixel colortypes). Return 0 for kUnknown_SkColorType.
	*/
	int shiftPerPixel() const { return fInfo.shiftPerPixel(); }

	uint64_t getSize64() const { return sk_64_mul(fInfo.height(), fRowBytes); }
	uint64_t getSafeSize64() const { return fInfo.getSafeSize64(fRowBytes); }
	size_t getSafeSize() const { return fInfo.getSafeSize(fRowBytes); }

	/**
	* This will brute-force return true if all of the pixels in the pixmap
	* are opaque. If there are no pixels, or encounters an error, returns false.
	*/
	bool computeIsOpaque() const;

	/**
	* Converts the pixel at the specified coordinate to an unpremultiplied
	* SkColor. Note: this ignores any SkColorSpace information, and may return
	* lower precision data than is actually in the pixel. Alpha only
	* colortypes (e.g. kAlpha_8_SkColorType) return black with the appropriate
	* alpha set. The value is undefined for kUnknown_SkColorType or if x or y
	* are out of bounds, or if the pixtap does not have any pixels.
	*/
	SkColor getColor(int x, int y) const;

	const void* addr(int x, int y) const {
	return (const char*)fPixels + fInfo.computeOffset(x, y, fRowBytes);
	}
	const uint8_t* addr8() const {
	SkASSERT(1 == SkColorTypeBytesPerPixel(fInfo.colorType()));
	return reinterpret_cast<const uint8_t*>(fPixels);
	}
	const uint16_t* addr16() const {
	SkASSERT(2 == SkColorTypeBytesPerPixel(fInfo.colorType()));
	return reinterpret_cast<const uint16_t*>(fPixels);
	}
	const uint32_t* addr32() const {
	SkASSERT(4 == SkColorTypeBytesPerPixel(fInfo.colorType()));
	return reinterpret_cast<const uint32_t*>(fPixels);
	}
	const uint64_t* addr64() const {
	SkASSERT(8 == SkColorTypeBytesPerPixel(fInfo.colorType()));
	return reinterpret_cast<const uint64_t*>(fPixels);
	}
	const uint16_t* addrF16() const {
	SkASSERT(8 == SkColorTypeBytesPerPixel(fInfo.colorType()));
	SkASSERT(kRGBA_F16_SkColorType == fInfo.colorType());
	return reinterpret_cast<const uint16_t*>(fPixels);
	}

	// Offset by the specified x,y coordinates

	const uint8_t* addr8(int x, int y) const {
	SkASSERT((unsigned)x < (unsigned)fInfo.width());
	SkASSERT((unsigned)y < (unsigned)fInfo.height());
	return (const uint8_t)((const char)this->addr8() + y * fRowBytes + (x << 0));
	}
	const uint16_t* addr16(int x, int y) const {
	SkASSERT((unsigned)x < (unsigned)fInfo.width());
	SkASSERT((unsigned)y < (unsigned)fInfo.height());
	return (const uint16_t)((const char)this->addr16() + y * fRowBytes + (x << 1));
	}
	const uint32_t* addr32(int x, int y) const {
	SkASSERT((unsigned)x < (unsigned)fInfo.width());
	SkASSERT((unsigned)y < (unsigned)fInfo.height());
	return (const uint32_t)((const char)this->addr32() + y * fRowBytes + (x << 2));
	}
	const uint64_t* addr64(int x, int y) const {
	SkASSERT((unsigned)x < (unsigned)fInfo.width());
	SkASSERT((unsigned)y < (unsigned)fInfo.height());
	return (const uint64_t)((const char)this->addr64() + y * fRowBytes + (x << 3));
	}
	const uint16_t* addrF16(int x, int y) const {
	SkASSERT(kRGBA_F16_SkColorType == fInfo.colorType());
	return reinterpret_cast<const uint16_t*>(this->addr64(x, y));
	}

	// Writable versions

	void* writable_addr() const { return const_cast<void*>(fPixels); }
	void* writable_addr(int x, int y) const {
	return const_cast<void*>(this->addr(x, y));
	}
	uint8_t* writable_addr8(int x, int y) const {
	return const_cast<uint8_t*>(this->addr8(x, y));
	}
	uint16_t* writable_addr16(int x, int y) const {
	return const_cast<uint16_t*>(this->addr16(x, y));
	}
	uint32_t* writable_addr32(int x, int y) const {
	return const_cast<uint32_t*>(this->addr32(x, y));
	}
	uint64_t* writable_addr64(int x, int y) const {
	return const_cast<uint64_t*>(this->addr64(x, y));
	}
	uint16_t* writable_addrF16(int x, int y) const {
	return reinterpret_cast<uint16_t*>(writable_addr64(x, y));
	}

	// copy methods

	bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
	int srcX, int srcY) const;
	bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes) const {
	return this->readPixels(dstInfo, dstPixels, dstRowBytes, 0, 0);
	}
	bool readPixels(const SkPixmap& dst, int srcX, int srcY) const {
	return this->readPixels(dst.info(), dst.writable_addr(), dst.rowBytes(), srcX, srcY);
	}
	bool readPixels(const SkPixmap& dst) const {
	return this->readPixels(dst.info(), dst.writable_addr(), dst.rowBytes(), 0, 0);
	}

	/**
	* Copy the pixels from this pixmap into the dst pixmap, converting as needed into dst's
	* colortype/alphatype. If the conversion cannot be performed, false is returned.
	*
	* If dst's dimensions differ from the src dimension, the image will be scaled, applying the
	* specified filter-quality.
	*/
	bool scalePixels(const SkPixmap& dst, SkFilterQuality) const;

	/**
	* Returns true if pixels were written to (e.g. if colorType is kUnknown_SkColorType, this
	* will return false). If subset does not intersect the bounds of this pixmap, returns false.
	*/
	bool erase(SkColor, const SkIRect& subset) const;

	bool erase(SkColor color) const { return this->erase(color, this->bounds()); }
	bool erase(const SkColor4f&, const SkIRect* subset = nullptr) const;

	private:
	const void* fPixels;
	SkColorTable* fCTable;
	size_t fRowBytes;
	SkImageInfo fInfo;
	};

	#endif