C++ SkPixmap类代码示例

uint8_t*
SourceSurfaceSkia::GetData()
{
#ifdef USE_SKIA_GPU
  if (mImage->isTextureBacked()) {
    sk_sp<SkImage> raster;
    if (sk_sp<SkData> data = MakeSkData(nullptr, mSize, mStride)) {
      SkImageInfo info = MakeSkiaImageInfo(mSize, mFormat);
      if (mImage->readPixels(info, data->writable_data(), mStride, 0, 0, SkImage::kDisallow_CachingHint)) {
        raster = SkImage::MakeRasterData(info, data, mStride);
      }
    }
    if (raster) {
      mImage = raster;
    } else {
      gfxCriticalError() << "Failed making Skia raster image for GPU surface";
    }
  }
#endif
  SkPixmap pixmap;
  if (!mImage->peekPixels(&pixmap)) {
    gfxCriticalError() << "Failed accessing pixels for Skia raster image";
  }
  return reinterpret_cast<uint8_t*>(pixmap.writable_addr());
}

    bool onGetROPixels(SkBitmap* dst) const override {
        const auto desc = SkBitmapCacheDesc::Make(this->uniqueID(), this->width(), this->height());
        if (SkBitmapCache::Find(desc, dst)) {
            SkASSERT(dst->getGenerationID() == this->uniqueID());
            SkASSERT(dst->isImmutable());
            SkASSERT(dst->getPixels());
            return true;
        }

        SkPixmap pmap;
        SkImageInfo info = SkImageInfo::MakeN32(this->width(), this->height(),
                                                this->alphaType(), fColorSpace);
        auto rec = SkBitmapCache::Alloc(desc, info, &pmap);
        if (!rec) {
            return false;
        }
        sk_sp<SkColorSpace> colorSpace;
        if (GrPixelConfigIsSRGB(fTextureProxy->config())) {
            colorSpace = SkColorSpace::MakeSRGB();
        }
        sk_sp<GrSurfaceContext> sContext = fContext->contextPriv().makeWrappedSurfaceContext(
                fTextureProxy, std::move(colorSpace));
        if (!sContext) {
            return false;
        }

        if (!sContext->readPixels(info, pmap.writable_addr(), pmap.rowBytes(), 0, 0)) {
            return false;
        }

        SkBitmapCache::Add(std::move(rec), dst);
        fAddedRasterVersionToCache.store(true);
        return true;
    }

std::unique_ptr<SkEncoder> SkPngEncoder::Make(SkWStream* dst, const SkPixmap& src,
                                              const Options& options) {
    if (!SkPixmapIsValid(src)) {
        return nullptr;
    }

    std::unique_ptr<SkPngEncoderMgr> encoderMgr = SkPngEncoderMgr::Make(dst);
    if (!encoderMgr) {
        return nullptr;
    }

    if (!encoderMgr->setHeader(src.info(), options)) {
        return nullptr;
    }

    if (!encoderMgr->setColorSpace(src.info())) {
        return nullptr;
    }

    if (!encoderMgr->writeInfo(src.info())) {
        return nullptr;
    }

    encoderMgr->chooseProc(src.info());

    return std::unique_ptr<SkPngEncoder>(new SkPngEncoder(std::move(encoderMgr), src));
}

/**
 *  For the purposes of drawing bitmaps, if a matrix is "almost" translate
 *  go ahead and treat it as if it were, so that subsequent code can go fast.
 */
static bool just_trans_clamp(const SkMatrix& matrix, const SkPixmap& pixmap) {
    SkASSERT(matrix_only_scale_translate(matrix));

    if (matrix.getType() & SkMatrix::kScale_Mask) {
        SkRect dst;
        SkRect src = SkRect::Make(pixmap.bounds());

        // Can't call mapRect(), since that will fix up inverted rectangles,
        // e.g. when scale is negative, and we don't want to return true for
        // those.
        matrix.mapPoints(SkTCast<SkPoint*>(&dst),
                         SkTCast<const SkPoint*>(&src),
                         2);

        // Now round all 4 edges to device space, and then compare the device
        // width/height to the original. Note: we must map all 4 and subtract
        // rather than map the "width" and compare, since we care about the
        // phase (in pixel space) that any translate in the matrix might impart.
        SkIRect idst;
        dst.round(&idst);
        return idst.width() == pixmap.width() && idst.height() == pixmap.height();
    }
    // if we got here, we're either kTranslate_Mask or identity
    return true;
}

void SkLinearGradient::
LinearGradient4fContext::D32_BlitBW(BlitState* state, int x, int y, const SkPixmap& dst,
                                    int count) {
    // FIXME: ignoring coverage for now
    const LinearGradient4fContext* ctx =
        static_cast<const LinearGradient4fContext*>(state->fCtx);

    if (!dst.info().gammaCloseToSRGB()) {
        if (ctx->fColorsArePremul) {
            ctx->shadePremulSpan<DstType::L32, ApplyPremul::False>(
                x, y, dst.writable_addr32(x, y), count);
        } else {
            ctx->shadePremulSpan<DstType::L32, ApplyPremul::True>(
                x, y, dst.writable_addr32(x, y), count);
        }
    } else {
        if (ctx->fColorsArePremul) {
            ctx->shadePremulSpan<DstType::S32, ApplyPremul::False>(
                x, y, dst.writable_addr32(x, y), count);
        } else {
            ctx->shadePremulSpan<DstType::S32, ApplyPremul::True>(
                x, y, dst.writable_addr32(x, y), count);
        }
    }
}

void SkLinearGradient::
LinearGradient4fContext::D32_BlitBW(BlitState* state, int x, int y, const SkPixmap& dst,
                                    int count) {
    // FIXME: ignoring coverage for now
    const LinearGradient4fContext* ctx =
        static_cast<const LinearGradient4fContext*>(state->fCtx);

    if (dst.info().isLinear()) {
        if (ctx->fColorsArePremul) {
            ctx->shadePremulSpan<SkPMColor, kLinear_SkColorProfileType, ApplyPremul::False>(
                x, y, dst.writable_addr32(x, y), count);
        } else {
            ctx->shadePremulSpan<SkPMColor, kLinear_SkColorProfileType, ApplyPremul::True>(
                x, y, dst.writable_addr32(x, y), count);
        }
    } else {
        if (ctx->fColorsArePremul) {
            ctx->shadePremulSpan<SkPMColor, kSRGB_SkColorProfileType, ApplyPremul::False>(
                x, y, dst.writable_addr32(x, y), count);
        } else {
            ctx->shadePremulSpan<SkPMColor, kSRGB_SkColorProfileType, ApplyPremul::True>(
                x, y, dst.writable_addr32(x, y), count);
        }
    }
}

bool copy_to(SkBitmap* dst, SkColorType dstColorType, const SkBitmap& src) {
    SkPixmap srcPM;
    if (!src.peekPixels(&srcPM)) {
        return false;
    }

    SkBitmap tmpDst;
    SkImageInfo dstInfo = srcPM.info().makeColorType(dstColorType);
    if (!tmpDst.setInfo(dstInfo)) {
        return false;
    }

    if (!tmpDst.tryAllocPixels()) {
        return false;
    }

    SkPixmap dstPM;
    if (!tmpDst.peekPixels(&dstPM)) {
        return false;
    }

    if (!srcPM.readPixels(dstPM)) {
        return false;
    }

    dst->swap(tmpDst);
    return true;
}

std::unique_ptr<SkEncoder> SkJpegEncoder::Make(SkWStream* dst, const SkPixmap& src,
                                               const Options& options) {
    if (!SkPixmapIsValid(src, options.fBlendBehavior)) {
        return nullptr;
    }

    std::unique_ptr<SkJpegEncoderMgr> encoderMgr = SkJpegEncoderMgr::Make(dst);
    if (setjmp(encoderMgr->jmpBuf())) {
        return nullptr;
    }

    if (!encoderMgr->setParams(src.info(), options)) {
        return nullptr;
    }

    jpeg_set_quality(encoderMgr->cinfo(), options.fQuality, TRUE);
    jpeg_start_compress(encoderMgr->cinfo(), TRUE);

    sk_sp<SkData> icc = icc_from_color_space(src.info());
    if (icc) {
        // Create a contiguous block of memory with the icc signature followed by the profile.
        sk_sp<SkData> markerData =
                SkData::MakeUninitialized(kICCMarkerHeaderSize + icc->size());
        uint8_t* ptr = (uint8_t*) markerData->writable_data();
        memcpy(ptr, kICCSig, sizeof(kICCSig));
        ptr += sizeof(kICCSig);
        *ptr++ = 1; // This is the first marker.
        *ptr++ = 1; // Out of one total markers.
        memcpy(ptr, icc->data(), icc->size());

        jpeg_write_marker(encoderMgr->cinfo(), kICCMarker, markerData->bytes(), markerData->size());
    }

    return std::unique_ptr<SkJpegEncoder>(new SkJpegEncoder(std::move(encoderMgr), src));
}

static void call_proc_X(SkMorphologyImageFilter::Proc procX,
                        const SkPixmap& src, SkBitmap* dst,
                        int radiusX, const SkIRect& bounds) {
    procX(src.addr32(bounds.left(), bounds.top()), dst->getAddr32(0, 0),
          radiusX, bounds.width(), bounds.height(),
          src.rowBytesAsPixels(), dst->rowBytesAsPixels());
}

 static bool Supports(const SkPixmap& dst, const SkPixmap& src, const SkPaint& paint) {
     if (dst.colorType() != src.colorType()) {
         return false;
     }
     if (dst.info().profileType() != src.info().profileType()) {
         return false;
     }
     if (paint.getMaskFilter() || paint.getColorFilter() || paint.getImageFilter()) {
         return false;
     }
     if (0xFF != paint.getAlpha()) {
         return false;
     }
     SkXfermode::Mode mode;
     if (!SkXfermode::AsMode(paint.getXfermode(), &mode)) {
         return false;
     }
     if (SkXfermode::kSrc_Mode == mode) {
         return true;
     }
     if (SkXfermode::kSrcOver_Mode == mode && src.isOpaque()) {
         return true;
     }
     return false;
 }

bool SkLinearBitmapPipeline::ClonePipelineForBlitting(
    SkEmbeddableLinearPipeline* pipelineStorage,
    const SkLinearBitmapPipeline& pipeline,
    SkMatrix::TypeMask matrixMask,
    SkShader::TileMode xTileMode,
    SkShader::TileMode yTileMode,
    SkFilterQuality filterQuality,
    const SkPixmap& srcPixmap,
    float finalAlpha,
    SkXfermode::Mode xferMode,
    const SkImageInfo& dstInfo)
{
    if (xferMode == SkXfermode::kSrcOver_Mode
        && srcPixmap.info().alphaType() == kOpaque_SkAlphaType) {
        xferMode = SkXfermode::kSrc_Mode;
    }

    if (matrixMask & ~SkMatrix::kTranslate_Mask ) { return false; }
    if (filterQuality != SkFilterQuality::kNone_SkFilterQuality) { return false; }
    if (finalAlpha != 1.0f) { return false; }
    if (srcPixmap.info().colorType() != kRGBA_8888_SkColorType
        || dstInfo.colorType() != kRGBA_8888_SkColorType) { return false; }

    if (!srcPixmap.info().gammaCloseToSRGB() || !dstInfo.gammaCloseToSRGB()) {
        return false;
    }

    if (xferMode != SkXfermode::kSrc_Mode && xferMode != SkXfermode::kSrcOver_Mode) {
        return false;
    }

    pipelineStorage->init(pipeline, srcPixmap, xferMode, dstInfo);

    return true;
}

 SkSpecialImage_Raster(const SkIRect& subset,
                       const SkPixmap& pixmap,
                       RasterReleaseProc releaseProc,
                       ReleaseContext context,
                       const SkSurfaceProps* props)
     : INHERITED(subset, kNeedNewImageUniqueID_SpecialImage, props) {
     fBitmap.installPixels(pixmap.info(), pixmap.writable_addr(),
                           pixmap.rowBytes(), pixmap.ctable(),
                           releaseProc, context);
 }

bool SkPixmap::scalePixels(const SkPixmap& dst, SkFilterQuality quality) const {
    // Can't do anthing with empty src or dst
    if (this->width() <= 0 || this->height() <= 0 || dst.width() <= 0 || dst.height() <= 0) {
        return false;
    }

    // no scaling involved?
    if (dst.width() == this->width() && dst.height() == this->height()) {
        return this->readPixels(dst);
    }

    SkBitmap bitmap;
    if (!bitmap.installPixels(*this)) {
        return false;
    }
    bitmap.setIsVolatile(true); // so we don't try to cache it

    SkAutoTUnref<SkSurface> surface(SkSurface::NewRasterDirect(dst.info(), dst.writable_addr(),
                                                               dst.rowBytes()));
    if (!surface) {
        return false;
    }

    SkPaint paint;
    paint.setFilterQuality(quality);
    paint.setXfermodeMode(SkXfermode::kSrc_Mode);
    surface->getCanvas()->drawBitmapRect(bitmap, SkRect::MakeIWH(dst.width(), dst.height()),
                                         &paint);
    return true;
}

void draw(SkCanvas* canvas) {
    std::vector<int32_t> pixels;
    pixels.resize(image->height() * image->width() * 4);
    SkPixmap pixmap(SkImageInfo::Make(image->width(), image->height(), kN32_SkColorType,
            image->alphaType()), (const void*) &pixels.front(), image->width() * 4);
    image->readPixels(pixmap, 0, 0);
    SkDebugf("pixels address: 0x%llx\n", pixmap.addr());
    SkPixmap inset;
    if (pixmap.extractSubset(&inset, {128, 128, 512, 512})) {
         SkDebugf("inset address:  0x%llx\n", inset.addr());
    }
}

const void* SkSurface::peekPixels(SkImageInfo* info, size_t* rowBytes) {
    SkPixmap pm;
    if (this->peekPixels(&pm)) {
        if (info) {
            *info = pm.info();
        }
        if (rowBytes) {
            *rowBytes = pm.rowBytes();
        }
        return pm.addr();
    }
    return nullptr;
}