| /* |
| * Copyright 2013 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkAlphaThresholdFilter.h" |
| |
| #include "SkBitmap.h" |
| #include "SkReadBuffer.h" |
| #include "SkSpecialImage.h" |
| #include "SkWriteBuffer.h" |
| #include "SkRegion.h" |
| |
| #if SK_SUPPORT_GPU |
| #include "GrAlphaThresholdFragmentProcessor.h" |
| #include "GrContext.h" |
| #include "GrDrawContext.h" |
| #endif |
| |
| class SK_API SkAlphaThresholdFilterImpl : public SkImageFilter { |
| public: |
| SkAlphaThresholdFilterImpl(const SkRegion& region, SkScalar innerThreshold, |
| SkScalar outerThreshold, sk_sp<SkImageFilter> input, |
| const CropRect* cropRect = nullptr); |
| |
| SK_TO_STRING_OVERRIDE() |
| SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAlphaThresholdFilterImpl) |
| friend void SkAlphaThresholdFilter::InitializeFlattenables(); |
| |
| protected: |
| void flatten(SkWriteBuffer&) const override; |
| |
| sk_sp<SkSpecialImage> onFilterImage(SkSpecialImage* source, const Context&, |
| SkIPoint* offset) const override; |
| |
| #if SK_SUPPORT_GPU |
| sk_sp<GrTexture> createMaskTexture(GrContext*, const SkMatrix&, const SkIRect& bounds) const; |
| #endif |
| |
| private: |
| SkRegion fRegion; |
| SkScalar fInnerThreshold; |
| SkScalar fOuterThreshold; |
| typedef SkImageFilter INHERITED; |
| }; |
| |
| SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkAlphaThresholdFilter) |
| SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkAlphaThresholdFilterImpl) |
| SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END |
| |
| static SkScalar pin_0_1(SkScalar x) { |
| return SkMinScalar(SkMaxScalar(x, 0), 1); |
| } |
| |
| sk_sp<SkImageFilter> SkAlphaThresholdFilter::Make(const SkRegion& region, |
| SkScalar innerThreshold, |
| SkScalar outerThreshold, |
| sk_sp<SkImageFilter> input, |
| const SkImageFilter::CropRect* cropRect) { |
| innerThreshold = pin_0_1(innerThreshold); |
| outerThreshold = pin_0_1(outerThreshold); |
| if (!SkScalarIsFinite(innerThreshold) || !SkScalarIsFinite(outerThreshold)) { |
| return nullptr; |
| } |
| return sk_sp<SkImageFilter>(new SkAlphaThresholdFilterImpl(region, innerThreshold, |
| outerThreshold, |
| std::move(input), |
| cropRect)); |
| } |
| |
| sk_sp<SkFlattenable> SkAlphaThresholdFilterImpl::CreateProc(SkReadBuffer& buffer) { |
| SK_IMAGEFILTER_UNFLATTEN_COMMON(common, 1); |
| SkScalar inner = buffer.readScalar(); |
| SkScalar outer = buffer.readScalar(); |
| SkRegion rgn; |
| buffer.readRegion(&rgn); |
| return SkAlphaThresholdFilter::Make(rgn, inner, outer, common.getInput(0), |
| &common.cropRect()); |
| } |
| |
| SkAlphaThresholdFilterImpl::SkAlphaThresholdFilterImpl(const SkRegion& region, |
| SkScalar innerThreshold, |
| SkScalar outerThreshold, |
| sk_sp<SkImageFilter> input, |
| const CropRect* cropRect) |
| : INHERITED(&input, 1, cropRect) |
| , fRegion(region) |
| , fInnerThreshold(innerThreshold) |
| , fOuterThreshold(outerThreshold) { |
| } |
| |
| #if SK_SUPPORT_GPU |
| sk_sp<GrTexture> SkAlphaThresholdFilterImpl::createMaskTexture(GrContext* context, |
| const SkMatrix& inMatrix, |
| const SkIRect& bounds) const { |
| GrPixelConfig config; |
| if (context->caps()->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) { |
| config = kAlpha_8_GrPixelConfig; |
| } else { |
| config = kRGBA_8888_GrPixelConfig; |
| } |
| |
| sk_sp<GrDrawContext> drawContext(context->newDrawContext(SkBackingFit::kApprox, |
| bounds.width(), bounds.height(), |
| config)); |
| if (!drawContext) { |
| return nullptr; |
| } |
| |
| GrPaint grPaint; |
| grPaint.setPorterDuffXPFactory(SkXfermode::kSrc_Mode); |
| SkRegion::Iterator iter(fRegion); |
| drawContext->clear(nullptr, 0x0, true); |
| |
| GrFixedClip clip(SkIRect::MakeWH(bounds.width(), bounds.height())); |
| while (!iter.done()) { |
| SkRect rect = SkRect::Make(iter.rect()); |
| drawContext->drawRect(clip, grPaint, inMatrix, rect); |
| iter.next(); |
| } |
| |
| return drawContext->asTexture(); |
| } |
| #endif |
| |
| void SkAlphaThresholdFilterImpl::flatten(SkWriteBuffer& buffer) const { |
| this->INHERITED::flatten(buffer); |
| buffer.writeScalar(fInnerThreshold); |
| buffer.writeScalar(fOuterThreshold); |
| buffer.writeRegion(fRegion); |
| } |
| |
| sk_sp<SkSpecialImage> SkAlphaThresholdFilterImpl::onFilterImage(SkSpecialImage* source, |
| const Context& ctx, |
| SkIPoint* offset) const { |
| SkIPoint inputOffset = SkIPoint::Make(0, 0); |
| sk_sp<SkSpecialImage> input(this->filterInput(0, source, ctx, &inputOffset)); |
| if (!input) { |
| return nullptr; |
| } |
| |
| const SkIRect inputBounds = SkIRect::MakeXYWH(inputOffset.x(), inputOffset.y(), |
| input->width(), input->height()); |
| |
| SkIRect bounds; |
| if (!this->applyCropRect(ctx, inputBounds, &bounds)) { |
| return nullptr; |
| } |
| |
| #if SK_SUPPORT_GPU |
| if (source->isTextureBacked()) { |
| GrContext* context = source->getContext(); |
| |
| sk_sp<GrTexture> inputTexture(input->asTextureRef(context)); |
| SkASSERT(inputTexture); |
| |
| offset->fX = bounds.left(); |
| offset->fY = bounds.top(); |
| |
| bounds.offset(-inputOffset); |
| |
| SkMatrix matrix(ctx.ctm()); |
| matrix.postTranslate(SkIntToScalar(-bounds.left()), SkIntToScalar(-bounds.top())); |
| |
| sk_sp<GrTexture> maskTexture(this->createMaskTexture(context, matrix, bounds)); |
| if (!maskTexture) { |
| return nullptr; |
| } |
| |
| // SRGBTODO: handle sRGB here |
| sk_sp<GrFragmentProcessor> fp(GrAlphaThresholdFragmentProcessor::Make( |
| inputTexture.get(), |
| maskTexture.get(), |
| fInnerThreshold, |
| fOuterThreshold, |
| bounds)); |
| if (!fp) { |
| return nullptr; |
| } |
| |
| return DrawWithFP(context, std::move(fp), bounds, sk_ref_sp(input->getColorSpace())); |
| } |
| #endif |
| |
| SkBitmap inputBM; |
| |
| if (!input->getROPixels(&inputBM)) { |
| return nullptr; |
| } |
| |
| if (inputBM.colorType() != kN32_SkColorType) { |
| return nullptr; |
| } |
| |
| SkAutoLockPixels inputLock(inputBM); |
| |
| if (!inputBM.getPixels() || inputBM.width() <= 0 || inputBM.height() <= 0) { |
| return nullptr; |
| } |
| |
| |
| SkMatrix localInverse; |
| if (!ctx.ctm().invert(&localInverse)) { |
| return nullptr; |
| } |
| |
| SkImageInfo info = SkImageInfo::MakeN32(bounds.width(), bounds.height(), |
| kPremul_SkAlphaType); |
| |
| SkBitmap dst; |
| if (!dst.tryAllocPixels(info)) { |
| return nullptr; |
| } |
| |
| SkAutoLockPixels dstLock(dst); |
| |
| U8CPU innerThreshold = (U8CPU)(fInnerThreshold * 0xFF); |
| U8CPU outerThreshold = (U8CPU)(fOuterThreshold * 0xFF); |
| SkColor* dptr = dst.getAddr32(0, 0); |
| int dstWidth = dst.width(), dstHeight = dst.height(); |
| for (int y = 0; y < dstHeight; ++y) { |
| const SkColor* sptr = inputBM.getAddr32(bounds.fLeft, bounds.fTop+y); |
| |
| for (int x = 0; x < dstWidth; ++x) { |
| const SkColor& source = sptr[x]; |
| SkColor outputColor(source); |
| SkPoint position; |
| localInverse.mapXY((SkScalar)x + bounds.fLeft, (SkScalar)y + bounds.fTop, &position); |
| if (fRegion.contains((int32_t)position.x(), (int32_t)position.y())) { |
| if (SkColorGetA(source) < innerThreshold) { |
| U8CPU alpha = SkColorGetA(source); |
| if (alpha == 0) { |
| alpha = 1; |
| } |
| float scale = (float)innerThreshold / alpha; |
| outputColor = SkColorSetARGB(innerThreshold, |
| (U8CPU)(SkColorGetR(source) * scale), |
| (U8CPU)(SkColorGetG(source) * scale), |
| (U8CPU)(SkColorGetB(source) * scale)); |
| } |
| } else { |
| if (SkColorGetA(source) > outerThreshold) { |
| float scale = (float)outerThreshold / SkColorGetA(source); |
| outputColor = SkColorSetARGB(outerThreshold, |
| (U8CPU)(SkColorGetR(source) * scale), |
| (U8CPU)(SkColorGetG(source) * scale), |
| (U8CPU)(SkColorGetB(source) * scale)); |
| } |
| } |
| dptr[y * dstWidth + x] = outputColor; |
| } |
| } |
| |
| offset->fX = bounds.left(); |
| offset->fY = bounds.top(); |
| return SkSpecialImage::MakeFromRaster(SkIRect::MakeWH(bounds.width(), bounds.height()), |
| dst); |
| } |
| |
| #ifndef SK_IGNORE_TO_STRING |
| void SkAlphaThresholdFilterImpl::toString(SkString* str) const { |
| str->appendf("SkAlphaThresholdImageFilter: ("); |
| str->appendf("inner: %f outer: %f", fInnerThreshold, fOuterThreshold); |
| str->append(")"); |
| } |
| #endif |