C++ SkRect::isetWH方法代码示例

void SkBitmapDevice::drawBitmapRect(const SkDraw& draw, const SkBitmap& bitmap,
                                    const SkRect* src, const SkRect& dst,
                                    const SkPaint& paint,
                                    SkCanvas::DrawBitmapRectFlags flags) {
    SkMatrix    matrix;
    SkRect      bitmapBounds, tmpSrc, tmpDst;
    SkBitmap    tmpBitmap;

    bitmapBounds.isetWH(bitmap.width(), bitmap.height());

    // Compute matrix from the two rectangles
    if (src) {
        tmpSrc = *src;
    } else {
        tmpSrc = bitmapBounds;
    }
    matrix.setRectToRect(tmpSrc, dst, SkMatrix::kFill_ScaleToFit);

    const SkRect* dstPtr = &dst;
    const SkBitmap* bitmapPtr = &bitmap;

    // clip the tmpSrc to the bounds of the bitmap, and recompute dstRect if
    // needed (if the src was clipped). No check needed if src==null.
    if (src) {
        if (!bitmapBounds.contains(*src)) {
            if (!tmpSrc.intersect(bitmapBounds)) {
                return; // nothing to draw
            }
            // recompute dst, based on the smaller tmpSrc
            matrix.mapRect(&tmpDst, tmpSrc);
            dstPtr = &tmpDst;
        }

        // since we may need to clamp to the borders of the src rect within
        // the bitmap, we extract a subset.
        SkIRect srcIR;
        tmpSrc.roundOut(&srcIR);
        if (!bitmap.extractSubset(&tmpBitmap, srcIR)) {
            return;
        }
        bitmapPtr = &tmpBitmap;

        // Since we did an extract, we need to adjust the matrix accordingly
        SkScalar dx = 0, dy = 0;
        if (srcIR.fLeft > 0) {
            dx = SkIntToScalar(srcIR.fLeft);
        }
        if (srcIR.fTop > 0) {
            dy = SkIntToScalar(srcIR.fTop);
        }
        if (dx || dy) {
            matrix.preTranslate(dx, dy);
        }

        SkRect extractedBitmapBounds;
        extractedBitmapBounds.isetWH(bitmapPtr->width(), bitmapPtr->height());
        if (extractedBitmapBounds == tmpSrc) {
            // no fractional part in src, we can just call drawBitmap
            goto USE_DRAWBITMAP;
        }
    } else {
        USE_DRAWBITMAP:
        // We can go faster by just calling drawBitmap, which will concat the
        // matrix with the CTM, and try to call drawSprite if it can. If not,
        // it will make a shader and call drawRect, as we do below.
        this->drawBitmap(draw, *bitmapPtr, matrix, paint);
        return;
    }

    // construct a shader, so we can call drawRect with the dst
    SkShader* s = SkShader::CreateBitmapShader(*bitmapPtr,
                                               SkShader::kClamp_TileMode,
                                               SkShader::kClamp_TileMode,
                                               &matrix);
    if (NULL == s) {
        return;
    }

    SkPaint paintWithShader(paint);
    paintWithShader.setStyle(SkPaint::kFill_Style);
    paintWithShader.setShader(s)->unref();

    // Call ourself, in case the subclass wanted to share this setup code
    // but handle the drawRect code themselves.
    this->drawRect(draw, *dstPtr, paintWithShader);
}

void SkBitmapDevice::drawBitmapRect(const SkDraw& draw, const SkBitmap& bitmap,
                                    const SkRect* src, const SkRect& dst,
                                    const SkPaint& paint, SkCanvas::SrcRectConstraint constraint) {
    SkMatrix    matrix;
    SkRect      bitmapBounds, tmpSrc, tmpDst;
    SkBitmap    tmpBitmap;

    bitmapBounds.isetWH(bitmap.width(), bitmap.height());

    // Compute matrix from the two rectangles
    if (src) {
        tmpSrc = *src;
    } else {
        tmpSrc = bitmapBounds;
    }
    matrix.setRectToRect(tmpSrc, dst, SkMatrix::kFill_ScaleToFit);

    LogDrawScaleFactor(SkMatrix::Concat(*draw.fMatrix, matrix), paint.getFilterQuality());

    const SkRect* dstPtr = &dst;
    const SkBitmap* bitmapPtr = &bitmap;

    // clip the tmpSrc to the bounds of the bitmap, and recompute dstRect if
    // needed (if the src was clipped). No check needed if src==null.
    if (src) {
        if (!bitmapBounds.contains(*src)) {
            if (!tmpSrc.intersect(bitmapBounds)) {
                return; // nothing to draw
            }
            // recompute dst, based on the smaller tmpSrc
            matrix.mapRect(&tmpDst, tmpSrc);
            dstPtr = &tmpDst;
        }
    }

    if (src && !src->contains(bitmapBounds) &&
        SkCanvas::kFast_SrcRectConstraint == constraint &&
        paint.getFilterQuality() != kNone_SkFilterQuality) {
        // src is smaller than the bounds of the bitmap, and we are filtering, so we don't know
        // how much more of the bitmap we need, so we can't use extractSubset or drawBitmap,
        // but we must use a shader w/ dst bounds (which can access all of the bitmap needed).
        goto USE_SHADER;
    }

    if (src) {
        // since we may need to clamp to the borders of the src rect within
        // the bitmap, we extract a subset.
        const SkIRect srcIR = tmpSrc.roundOut();
        if (!bitmap.extractSubset(&tmpBitmap, srcIR)) {
            return;
        }
        bitmapPtr = &tmpBitmap;

        // Since we did an extract, we need to adjust the matrix accordingly
        SkScalar dx = 0, dy = 0;
        if (srcIR.fLeft > 0) {
            dx = SkIntToScalar(srcIR.fLeft);
        }
        if (srcIR.fTop > 0) {
            dy = SkIntToScalar(srcIR.fTop);
        }
        if (dx || dy) {
            matrix.preTranslate(dx, dy);
        }

        SkRect extractedBitmapBounds;
        extractedBitmapBounds.isetWH(bitmapPtr->width(), bitmapPtr->height());
        if (extractedBitmapBounds == tmpSrc) {
            // no fractional part in src, we can just call drawBitmap
            goto USE_DRAWBITMAP;
        }
    } else {
        USE_DRAWBITMAP:
        // We can go faster by just calling drawBitmap, which will concat the
        // matrix with the CTM, and try to call drawSprite if it can. If not,
        // it will make a shader and call drawRect, as we do below.
        if (CanApplyDstMatrixAsCTM(matrix, paint)) {
            draw.drawBitmap(*bitmapPtr, matrix, dstPtr, paint);
            return;
        }
    }

    USE_SHADER:

    // Since the shader need only live for our stack-frame, pass in a custom allocator. This
    // can save malloc calls, and signals to SkMakeBitmapShader to not try to copy the bitmap
    // if its mutable, since that precaution is not needed (give the short lifetime of the shader).
    SkTBlitterAllocator allocator;
    // construct a shader, so we can call drawRect with the dst
    auto s = SkMakeBitmapShader(*bitmapPtr, SkShader::kClamp_TileMode, SkShader::kClamp_TileMode,
                                &matrix, kNever_SkCopyPixelsMode, &allocator);
    if (!s) {
        return;
    }
    // we deliberately add a ref, since the allocator wants to be the last owner
    s.get()->ref();

    SkPaint paintWithShader(paint);
    paintWithShader.setStyle(SkPaint::kFill_Style);
    paintWithShader.setShader(s);
//.........这里部分代码省略.........