C++ SkBitmap::getTexture方法代码示例

void SkDevice::writePixels(const SkBitmap& bitmap,
                           int x, int y,
                           SkCanvas::Config8888 config8888) {
    if (bitmap.isNull() || bitmap.getTexture()) {
        return;
    }
    const SkBitmap* sprite = &bitmap;
    // check whether we have to handle a config8888 that doesn't match SkPMColor
    if (SkBitmap::kARGB_8888_Config == bitmap.config() &&
        SkCanvas::kNative_Premul_Config8888 != config8888 &&
        kPMColorAlias != config8888) {

        // We're going to have to convert from a config8888 to the native config
        // First we clip to the device bounds.
        SkBitmap dstBmp = this->accessBitmap(true);
        SkIRect spriteRect = SkIRect::MakeXYWH(x, y,
                                               bitmap.width(), bitmap.height());
        SkIRect devRect = SkIRect::MakeWH(dstBmp.width(), dstBmp.height());
        if (!spriteRect.intersect(devRect)) {
            return;
        }

        // write directly to the device if it has pixels and is SkPMColor
        bool drawSprite;
        if (SkBitmap::kARGB_8888_Config == dstBmp.config() && !dstBmp.isNull()) {
            // we can write directly to the dst when doing the conversion
            dstBmp.extractSubset(&dstBmp, spriteRect);
            drawSprite = false;
        } else {
            // we convert to a temporary bitmap and draw that as a sprite
            dstBmp.setConfig(SkBitmap::kARGB_8888_Config,
                             spriteRect.width(),
                             spriteRect.height());
            if (!dstBmp.allocPixels()) {
                return;
            }
            drawSprite = true;
        }

        // copy pixels to dstBmp and convert from config8888 to native config.
        SkAutoLockPixels alp(bitmap);
        uint32_t* srcPixels = bitmap.getAddr32(spriteRect.fLeft - x,
                                               spriteRect.fTop - y);
        SkCopyConfig8888ToBitmap(dstBmp,
                                 srcPixels,
                                 bitmap.rowBytes(),
                                 config8888);

        if (drawSprite) {
            // we've clipped the sprite when we made a copy
            x = spriteRect.fLeft;
            y = spriteRect.fTop;
            sprite = &dstBmp;
        } else {
            return;
        }
    }

    SkPaint paint;
    paint.setXfermodeMode(SkXfermode::kSrc_Mode);
    SkRasterClip clip(SkIRect::MakeWH(fBitmap.width(), fBitmap.height()));
    SkDraw  draw;
    draw.fRC = &clip;
    draw.fClip = &clip.bwRgn();
    draw.fBitmap = &fBitmap; // canvas should have already called accessBitmap
    draw.fMatrix = &SkMatrix::I();
    this->drawSprite(draw, *sprite, x, y, paint);
}

bool SkDisplacementMapEffect::filterImageGPU(Proxy* proxy, const SkBitmap& src, const Context& ctx,
                                             SkBitmap* result, SkIPoint* offset) const {
    SkBitmap colorBM = src;
    SkIPoint colorOffset = SkIPoint::Make(0, 0);
    if (!this->filterInputGPU(1, proxy, src, ctx, &colorBM, &colorOffset)) {
        return false;
    }
    SkBitmap displacementBM = src;
    SkIPoint displacementOffset = SkIPoint::Make(0, 0);
    if (!this->filterInputGPU(0, proxy, src, ctx, &displacementBM, &displacementOffset)) {
        return false;
    }
    SkIRect bounds;
    // Since GrDisplacementMapEffect does bounds checking on color pixel access, we don't need to
    // pad the color bitmap to bounds here.
    if (!this->applyCropRect(ctx, colorBM, colorOffset, &bounds)) {
        return false;
    }
    SkIRect displBounds;
    if (!this->applyCropRect(ctx, proxy, displacementBM,
                             &displacementOffset, &displBounds, &displacementBM)) {
        return false;
    }
    if (!bounds.intersect(displBounds)) {
        return false;
    }
    GrTexture* color = colorBM.getTexture();
    GrTexture* displacement = displacementBM.getTexture();
    GrContext* context = color->getContext();

    GrSurfaceDesc desc;
    desc.fFlags = kRenderTarget_GrSurfaceFlag;
    desc.fWidth = bounds.width();
    desc.fHeight = bounds.height();
    desc.fConfig = kSkia8888_GrPixelConfig;

    SkAutoTUnref<GrTexture> dst(context->textureProvider()->createApproxTexture(desc));

    if (!dst) {
        return false;
    }

    SkVector scale = SkVector::Make(fScale, fScale);
    ctx.ctm().mapVectors(&scale, 1);

    GrPaint paint;
    SkMatrix offsetMatrix = GrCoordTransform::MakeDivByTextureWHMatrix(displacement);
    offsetMatrix.preTranslate(SkIntToScalar(colorOffset.fX - displacementOffset.fX),
                              SkIntToScalar(colorOffset.fY - displacementOffset.fY));

    paint.addColorFragmentProcessor(
        GrDisplacementMapEffect::Create(fXChannelSelector,
                                        fYChannelSelector,
                                        scale,
                                        displacement,
                                        offsetMatrix,
                                        color,
                                        colorBM.dimensions()))->unref();
    paint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode);
    SkIRect colorBounds = bounds;
    colorBounds.offset(-colorOffset);
    SkMatrix matrix;
    matrix.setTranslate(-SkIntToScalar(colorBounds.x()),
                        -SkIntToScalar(colorBounds.y()));

    SkAutoTUnref<GrDrawContext> drawContext(context->drawContext(dst->asRenderTarget()));
    if (!drawContext) {
        return false;
    }

    drawContext->drawRect(GrClip::WideOpen(), paint, matrix, SkRect::Make(colorBounds));
    offset->fX = bounds.left();
    offset->fY = bounds.top();
    GrWrapTextureInBitmap(dst, bounds.width(), bounds.height(), false, result);
    return true;
}