SkBitmap.h

/*
 * Copyright 2006 The Android Open Source Project
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef SkBitmap_DEFINED
#define SkBitmap_DEFINED

#include "SkColor.h"
#include "SkColorTable.h"
#include "SkImageInfo.h"
#include "SkPixmap.h"
#include "SkPoint.h"
#include "SkRefCnt.h"

struct SkMask;
struct SkIRect;
struct SkRect;
class SkPaint;
class SkPixelRef;
class SkString;

class SK_API SkBitmap {
public:
    class SK_API Allocator;

    SkBitmap();

    SkBitmap(const SkBitmap& src);

    SkBitmap(SkBitmap&& src);

    ~SkBitmap();

    SkBitmap& operator=(const SkBitmap& src);

    SkBitmap& operator=(SkBitmap&& src);

    //  This method is not exported to java.
    void swap(SkBitmap& other);


    const SkImageInfo& info() const { return fInfo; }

    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(); }
    sk_sp<SkColorSpace> refColorSpace() const { return fInfo.refColorSpace(); }

    int bytesPerPixel() const { return fInfo.bytesPerPixel(); }

    int rowBytesAsPixels() const {
        return fRowBytes >> this->shiftPerPixel();
    }

    int shiftPerPixel() const { return this->fInfo.shiftPerPixel(); }


    bool empty() const { return fInfo.isEmpty(); }

    bool isNull() const { return nullptr == fPixelRef; }

    bool drawsNothing() const { return this->empty() || this->isNull(); }

    size_t rowBytes() const { return fRowBytes; }

    bool setAlphaType(SkAlphaType);

    void* getPixels() const { return fPixels; }

    size_t getSize() const { return fInfo.height() * fRowBytes; }

    size_t getSafeSize() const { return fInfo.getSafeSize(fRowBytes); }

    int64_t computeSize64() const {
        return sk_64_mul(fInfo.height(), fRowBytes);
    }

    int64_t computeSafeSize64() const {
        return fInfo.getSafeSize64(fRowBytes);
    }

    bool isImmutable() const;

    void setImmutable();

    bool isOpaque() const {
        return SkAlphaTypeIsOpaque(this->alphaType());
    }

    bool isVolatile() const;

    void setIsVolatile(bool);

    void reset();

    static bool ComputeIsOpaque(const SkBitmap& bm) {
        SkPixmap pmap;
        return bm.peekPixels(&pmap) && pmap.computeIsOpaque();
    }

    void getBounds(SkRect* bounds) const;
    void getBounds(SkIRect* bounds) const;

    SkIRect bounds() const { return fInfo.bounds(); }
    SkISize dimensions() const { return fInfo.dimensions(); }
    // Returns the bounds of this bitmap, offset by its pixelref origin.
    SkIRect getSubset() const {
        return SkIRect::MakeXYWH(fPixelRefOrigin.x(), fPixelRefOrigin.y(),
                                 fInfo.width(), fInfo.height());
    }

    bool setInfo(const SkImageInfo&, size_t rowBytes = 0);

    enum AllocFlags {
        kZeroPixels_AllocFlag   = 1 << 0,
    };
    bool SK_WARN_UNUSED_RESULT tryAllocPixels(const SkImageInfo& info, sk_sp<SkColorTable> ctable,
                                              uint32_t flags = 0);
    void allocPixels(const SkImageInfo& info, sk_sp<SkColorTable> ctable, uint32_t flags = 0) {
        if (!this->tryAllocPixels(info, std::move(ctable), flags)) {
            sk_throw();
        }
    }

    bool SK_WARN_UNUSED_RESULT tryAllocPixels(const SkImageInfo& info, size_t rowBytes);

    void allocPixels(const SkImageInfo& info, size_t rowBytes) {
        if (!this->tryAllocPixels(info, rowBytes)) {
            sk_throw();
        }
    }

    bool SK_WARN_UNUSED_RESULT tryAllocPixels(const SkImageInfo& info) {
        return this->tryAllocPixels(info, info.minRowBytes());
    }

    void allocPixels(const SkImageInfo& info) {
        this->allocPixels(info, info.minRowBytes());
    }

    bool SK_WARN_UNUSED_RESULT tryAllocN32Pixels(int width, int height, bool isOpaque = false) {
        SkImageInfo info = SkImageInfo::MakeN32(width, height,
                                            isOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
        return this->tryAllocPixels(info);
    }

    void allocN32Pixels(int width, int height, bool isOpaque = false) {
        SkImageInfo info = SkImageInfo::MakeN32(width, height,
                                            isOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
        this->allocPixels(info);
    }

    // TEMPORARY -- remove after updating Android BitmapTests.cpp:35
    void allocPixels(const SkImageInfo& info, std::nullptr_t, SkColorTable* ctable) {
        this->allocPixels(info, sk_ref_sp(ctable));
    }

    bool installPixels(const SkImageInfo&, void* pixels, size_t rowBytes, SkColorTable*,
                       void (*releaseProc)(void* addr, void* context), void* context);

    bool installPixels(const SkImageInfo& info, void* pixels, size_t rowBytes) {
        return this->installPixels(info, pixels, rowBytes, NULL, NULL, NULL);
    }

    bool installPixels(const SkPixmap&);

    bool installMaskPixels(const SkMask&);

    void setPixels(void* p, SkColorTable* ctable = NULL);

    bool SK_WARN_UNUSED_RESULT tryAllocPixels(SkColorTable* ctable = NULL) {
        return this->tryAllocPixels(NULL, ctable);
    }

    void allocPixels(SkColorTable* ctable = NULL) {
        this->allocPixels(NULL, ctable);
    }

    bool SK_WARN_UNUSED_RESULT tryAllocPixels(Allocator* allocator, SkColorTable* ctable);

    void allocPixels(Allocator* allocator, SkColorTable* ctable) {
        if (!this->tryAllocPixels(allocator, ctable)) {
            sk_throw();
        }
    }

    SkPixelRef* pixelRef() const { return fPixelRef.get(); }

    SkIPoint pixelRefOrigin() const { return fPixelRefOrigin; }

    void setPixelRef(sk_sp<SkPixelRef>, int dx, int dy);

    bool readyToDraw() const {
        return this->getPixels() != NULL &&
               (this->colorType() != kIndex_8_SkColorType || this->getColorTable());
    }

    SkColorTable* getColorTable() const;

    uint32_t getGenerationID() const;

    void notifyPixelsChanged() const;

    void eraseColor(SkColor c) const;

    void eraseARGB(U8CPU a, U8CPU r, U8CPU g, U8CPU b) const {
        this->eraseColor(SkColorSetARGB(a, r, g, b));
    }

    SK_ATTR_DEPRECATED("use eraseARGB or eraseColor")
    void eraseRGB(U8CPU r, U8CPU g, U8CPU b) const {
        this->eraseARGB(0xFF, r, g, b);
    }

    void erase(SkColor c, const SkIRect& area) const;

    // DEPRECATED
    void eraseArea(const SkIRect& area, SkColor c) const {
        this->erase(c, area);
    }

    SkColor getColor(int x, int y) const {
        SkPixmap pixmap;
        SkAssertResult(this->peekPixels(&pixmap));
        return pixmap.getColor(x, y);
    }

    void* getAddr(int x, int y) const;

    inline uint32_t* getAddr32(int x, int y) const;

    inline uint16_t* getAddr16(int x, int y) const;

    inline uint8_t* getAddr8(int x, int y) const;

    inline SkPMColor getIndex8Color(int x, int y) const;

    bool extractSubset(SkBitmap* dst, const SkIRect& subset) const;

    bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
                    int srcX, int srcY, SkTransferFunctionBehavior behavior) const;
    bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
                    int srcX, int srcY) const {
        return this->readPixels(dstInfo, dstPixels, dstRowBytes, srcX, srcY,
                SkTransferFunctionBehavior::kRespect);
    }
    bool readPixels(const SkPixmap& dst, int srcX, int srcY) const;
    bool readPixels(const SkPixmap& dst) const {
        return this->readPixels(dst, 0, 0);
    }

    bool writePixels(const SkPixmap& src, int dstX, int dstY) {
        return this->writePixels(src, dstX, dstY, SkTransferFunctionBehavior::kRespect);
    }
    bool writePixels(const SkPixmap& src) {
        return this->writePixels(src, 0, 0);
    }
    bool writePixels(const SkPixmap& src, int x, int y, SkTransferFunctionBehavior behavior);

#ifdef SK_BUILD_FOR_ANDROID
    bool hasHardwareMipMap() const {
        return (fFlags & kHasHardwareMipMap_Flag) != 0;
    }

    void setHasHardwareMipMap(bool hasHardwareMipMap) {
        if (hasHardwareMipMap) {
            fFlags |= kHasHardwareMipMap_Flag;
        } else {
            fFlags &= ~kHasHardwareMipMap_Flag;
        }
    }
#endif

    bool extractAlpha(SkBitmap* dst) const {
        return this->extractAlpha(dst, NULL, NULL, NULL);
    }

    bool extractAlpha(SkBitmap* dst, const SkPaint* paint,
                      SkIPoint* offset) const {
        return this->extractAlpha(dst, paint, NULL, offset);
    }

    bool extractAlpha(SkBitmap* dst, const SkPaint* paint, Allocator* allocator,
                      SkIPoint* offset) const;

    bool peekPixels(SkPixmap*) const;

    SkDEBUGCODE(void validate() const;)

    class Allocator : public SkRefCnt {
    public:
        virtual bool allocPixelRef(SkBitmap*, SkColorTable*) = 0;
    private:
        typedef SkRefCnt INHERITED;
    };

    class HeapAllocator : public Allocator {
    public:
        bool allocPixelRef(SkBitmap*, SkColorTable*) override;
    };

    SK_TO_STRING_NONVIRT()

private:
    enum Flags {
        kImageIsVolatile_Flag   = 0x02,
#ifdef SK_BUILD_FOR_ANDROID
        /* A hint for the renderer responsible for drawing this bitmap
         * indicating that it should attempt to use mipmaps when this bitmap
         * is drawn scaled down.
         */
        kHasHardwareMipMap_Flag = 0x08,
#endif
    };

    sk_sp<SkPixelRef>   fPixelRef;
    void*               fPixels;
    SkIPoint            fPixelRefOrigin;
    SkImageInfo         fInfo;
    uint32_t            fRowBytes;
    uint8_t             fFlags;

    /*  Unreference any pixelrefs or colortables
    */
    void freePixels();
    void updatePixelsFromRef();

    static void WriteRawPixels(SkWriteBuffer*, const SkBitmap&);
    static bool ReadRawPixels(SkReadBuffer*, SkBitmap*);

    friend class SkReadBuffer;        // unflatten, rawpixels
    friend class SkBinaryWriteBuffer; // rawpixels
};


inline uint32_t* SkBitmap::getAddr32(int x, int y) const {
    SkASSERT(fPixels);
    SkASSERT(4 == this->bytesPerPixel());
    SkASSERT((unsigned)x < (unsigned)this->width() && (unsigned)y < (unsigned)this->height());
    return (uint32_t*)((char*)fPixels + y * fRowBytes + (x << 2));
}

inline uint16_t* SkBitmap::getAddr16(int x, int y) const {
    SkASSERT(fPixels);
    SkASSERT(2 == this->bytesPerPixel());
    SkASSERT((unsigned)x < (unsigned)this->width() && (unsigned)y < (unsigned)this->height());
    return (uint16_t*)((char*)fPixels + y * fRowBytes + (x << 1));
}

inline uint8_t* SkBitmap::getAddr8(int x, int y) const {
    SkASSERT(fPixels);
    SkASSERT(1 == this->bytesPerPixel());
    SkASSERT((unsigned)x < (unsigned)this->width() && (unsigned)y < (unsigned)this->height());
    return (uint8_t*)fPixels + y * fRowBytes + x;
}

inline SkPMColor SkBitmap::getIndex8Color(int x, int y) const {
    SkASSERT(fPixels);
    SkASSERT(kIndex_8_SkColorType == this->colorType());
    SkASSERT((unsigned)x < (unsigned)this->width() && (unsigned)y < (unsigned)this->height());
    SkASSERT(this->getColorTable());
    return (*this->getColorTable())[*((const uint8_t*)fPixels + y * fRowBytes + x)];
}

#endif