| /* |
| * Copyright 2019 Google LLC |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "src/core/SkImageFilterTypes.h" |
| |
| #include "include/core/SkImage.h" |
| #include "include/core/SkPicture.h" |
| #include "include/core/SkShader.h" |
| #include "include/core/SkTileMode.h" |
| #include "src/core/SkColorFilterBase.h" |
| #include "src/core/SkImageFilter_Base.h" |
| #include "src/core/SkMatrixPriv.h" |
| #include "src/core/SkRectPriv.h" |
| #include "src/core/SkSpecialSurface.h" |
| |
| namespace skif { |
| |
| namespace { |
| |
| // This exists to cover up issues where infinite precision would produce integers but float |
| // math produces values just larger/smaller than an int and roundOut/In on bounds would produce |
| // nearly a full pixel error. One such case is crbug.com/1313579 where the caller has produced |
| // near integer CTM and uses integer crop rects that would grab an extra row/column of the |
| // input image when using a strict roundOut. |
| static constexpr float kRoundEpsilon = 1e-3f; |
| |
| // Both [I]Vectors and Sk[I]Sizes are transformed as non-positioned values, i.e. go through |
| // mapVectors() not mapPoints(). |
| SkIVector map_as_vector(int32_t x, int32_t y, const SkMatrix& matrix) { |
| SkVector v = SkVector::Make(SkIntToScalar(x), SkIntToScalar(y)); |
| matrix.mapVectors(&v, 1); |
| return SkIVector::Make(SkScalarRoundToInt(v.fX), SkScalarRoundToInt(v.fY)); |
| } |
| |
| SkVector map_as_vector(SkScalar x, SkScalar y, const SkMatrix& matrix) { |
| SkVector v = SkVector::Make(x, y); |
| matrix.mapVectors(&v, 1); |
| return v; |
| } |
| |
| SkRect map_rect(const SkMatrix& matrix, const SkRect& rect) { |
| return rect.isEmpty() ? SkRect::MakeEmpty() : matrix.mapRect(rect); |
| } |
| |
| SkIRect map_rect(const SkMatrix& matrix, const SkIRect& rect) { |
| if (rect.isEmpty()) { |
| return SkIRect::MakeEmpty(); |
| } |
| // Unfortunately, there is a range of integer values such that we have 1px precision as an int, |
| // but less precision as a float. This can lead to non-empty SkIRects becoming empty simply |
| // because of float casting. If we're already dealing with a float rect or having a float |
| // output, that's what we're stuck with; but if we are starting form an irect and desiring an |
| // SkIRect output, we go through efforts to preserve the 1px precision for simple transforms. |
| if (matrix.isScaleTranslate()) { |
| double l = (double)matrix.getScaleX()*rect.fLeft + (double)matrix.getTranslateX(); |
| double r = (double)matrix.getScaleX()*rect.fRight + (double)matrix.getTranslateX(); |
| double t = (double)matrix.getScaleY()*rect.fTop + (double)matrix.getTranslateY(); |
| double b = (double)matrix.getScaleY()*rect.fBottom + (double)matrix.getTranslateY(); |
| return {sk_double_saturate2int(sk_double_floor(std::min(l, r) + kRoundEpsilon)), |
| sk_double_saturate2int(sk_double_floor(std::min(t, b) + kRoundEpsilon)), |
| sk_double_saturate2int(sk_double_ceil(std::max(l, r) - kRoundEpsilon)), |
| sk_double_saturate2int(sk_double_ceil(std::max(t, b) - kRoundEpsilon))}; |
| } else { |
| return skif::RoundOut(matrix.mapRect(SkRect::Make(rect))); |
| } |
| } |
| |
| bool inverse_map_rect(const SkMatrix& matrix, const SkRect& rect, SkRect* out) { |
| if (rect.isEmpty()) { |
| *out = SkRect::MakeEmpty(); |
| return true; |
| } |
| return SkMatrixPriv::InverseMapRect(matrix, out, rect); |
| } |
| |
| bool inverse_map_rect(const SkMatrix& matrix, const SkIRect& rect, SkIRect* out) { |
| if (rect.isEmpty()) { |
| *out = SkIRect::MakeEmpty(); |
| return true; |
| } |
| // This is a specialized inverse equivalent to the 1px precision preserving map_rect above. |
| if (matrix.isScaleTranslate()) { |
| // A scale-translate matrix with a 0 scale factor is not invertible. |
| if (matrix.getScaleX() == 0.f || matrix.getScaleY() == 0.f) { |
| return false; |
| } |
| double l = (rect.fLeft - (double)matrix.getTranslateX()) / (double)matrix.getScaleX(); |
| double r = (rect.fRight - (double)matrix.getTranslateX()) / (double)matrix.getScaleX(); |
| double t = (rect.fTop - (double)matrix.getTranslateY()) / (double)matrix.getScaleY(); |
| double b = (rect.fBottom - (double)matrix.getTranslateY()) / (double)matrix.getScaleY(); |
| |
| *out = {sk_double_saturate2int(sk_double_floor(std::min(l, r) + kRoundEpsilon)), |
| sk_double_saturate2int(sk_double_floor(std::min(t, b) + kRoundEpsilon)), |
| sk_double_saturate2int(sk_double_ceil(std::max(l, r) - kRoundEpsilon)), |
| sk_double_saturate2int(sk_double_ceil(std::max(t, b) - kRoundEpsilon))}; |
| return true; |
| } else { |
| SkRect mapped; |
| if (inverse_map_rect(matrix, SkRect::Make(rect), &mapped)) { |
| *out = skif::RoundOut(mapped); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| } |
| |
| // If m is epsilon within the form [1 0 tx], this returns true and sets out to [tx, ty] |
| // [0 1 ty] |
| // [0 0 1 ] |
| // TODO: Use this in decomposeCTM() (and possibly extend it to support is_nearly_scale_translate) |
| // to be a little more forgiving on matrix types during layer configuration. |
| bool is_nearly_integer_translation(const LayerSpace<SkMatrix>& m, |
| LayerSpace<SkIPoint>* out=nullptr) { |
| float tx = SkScalarRoundToScalar(sk_ieee_float_divide(m.rc(0,2), m.rc(2,2))); |
| float ty = SkScalarRoundToScalar(sk_ieee_float_divide(m.rc(1,2), m.rc(2,2))); |
| SkMatrix expected = SkMatrix::MakeAll(1.f, 0.f, tx, |
| 0.f, 1.f, ty, |
| 0.f, 0.f, 1.f); |
| for (int i = 0; i < 9; ++i) { |
| if (!SkScalarNearlyEqual(expected.get(i), m.get(i), kRoundEpsilon)) { |
| return false; |
| } |
| } |
| |
| if (out) { |
| *out = LayerSpace<SkIPoint>({(int) tx, (int) ty}); |
| } |
| return true; |
| } |
| |
| // Assumes 'image' is decal-tiled, so everything outside the image bounds but inside dstBounds is |
| // transparent black, in which case the returned special image may be smaller than dstBounds. |
| std::pair<sk_sp<SkSpecialImage>, LayerSpace<SkIPoint>> extract_subset( |
| const SkSpecialImage* image, |
| LayerSpace<SkIPoint> origin, |
| const LayerSpace<SkIRect>& dstBounds) { |
| LayerSpace<SkIRect> imageBounds(SkIRect::MakeXYWH(origin.x(), origin.y(), |
| image->width(), image->height())); |
| if (!imageBounds.intersect(dstBounds)) { |
| return {nullptr, {}}; |
| } |
| |
| // Offset the image subset directly to avoid issues negating (origin). With the prior |
| // intersection (bounds - origin) will be >= 0, but (bounds + (-origin)) may not, (e.g. |
| // origin is INT_MIN). |
| SkIRect subset = { imageBounds.left() - origin.x(), |
| imageBounds.top() - origin.y(), |
| imageBounds.right() - origin.x(), |
| imageBounds.bottom() - origin.y() }; |
| SkASSERT(subset.fLeft >= 0 && subset.fTop >= 0 && |
| subset.fRight <= image->width() && subset.fBottom <= image->height()); |
| |
| return {image->makeSubset(subset), imageBounds.topLeft()}; |
| } |
| |
| bool fills_layer_bounds(const SkColorFilter* colorFilter) { |
| return colorFilter && as_CFB(colorFilter)->affectsTransparentBlack(); |
| } |
| |
| // AutoSurface manages an SkSpecialSurface and canvas state to draw to a layer-space bounding box, |
| // and then snap it into a FilterResult. It provides operators to be used directly as a canvas, |
| // assuming surface creation succeeded. Usage: |
| // |
| // AutoSurface surface{ctx, dstBounds, renderInParameterSpace}; // if true, concats layer matrix |
| // if (surface) { |
| // surface->drawFoo(...); |
| // } |
| // return surface.snap(); // Automatically handles failed allocations |
| class AutoSurface { |
| public: |
| AutoSurface(const Context& ctx, |
| const LayerSpace<SkIRect>& dstBounds, |
| bool renderInParameterSpace, |
| const SkSurfaceProps* props = nullptr) |
| : fSurface(nullptr) |
| , fDstBounds(dstBounds) { |
| // We don't intersect by ctx.desiredOutput() and only use the Context to make the surface. |
| // It is assumed the caller has already accounted for the desired output, or it's a |
| // situation where the desired output shouldn't apply (e.g. this surface will be transformed |
| // to align with the actual desired output via FilterResult metadata). |
| fSurface = ctx.makeSurface(SkISize(fDstBounds.size()), props); |
| if (!fSurface) { |
| return; |
| } |
| |
| // Configure the canvas |
| SkCanvas* canvas = fSurface->getCanvas(); |
| // skbug.com/5075: GPU-backed special surfaces don't reset their contents. |
| canvas->clear(SK_ColorTRANSPARENT); |
| canvas->translate(-fDstBounds.left(), -fDstBounds.top()); // dst's origin adjustment |
| |
| if (renderInParameterSpace) { |
| canvas->concat(ctx.mapping().layerMatrix()); |
| } |
| } |
| |
| explicit operator bool() const { return SkToBool(fSurface); } |
| |
| SkCanvas* canvas() { SkASSERT(fSurface); return fSurface->getCanvas(); } |
| SkCanvas* operator->() { SkASSERT(fSurface); return fSurface->getCanvas(); } |
| |
| // NOTE: This pair is equivalent to a FilterResult but we keep it this way for use by resolve(), |
| // which wants them separate while the legacy imageAndOffset() function is around. |
| std::pair<sk_sp<SkSpecialImage>, LayerSpace<SkIPoint>> snap() { |
| if (fSurface) { |
| return {fSurface->makeImageSnapshot(), fDstBounds.topLeft()}; |
| } else { |
| return {nullptr, {}}; |
| } |
| } |
| |
| private: |
| sk_sp<SkSpecialSurface> fSurface; |
| LayerSpace<SkIRect> fDstBounds; |
| }; |
| |
| } // anonymous namespace |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| SkIRect RoundOut(SkRect r) { return r.makeInset(kRoundEpsilon, kRoundEpsilon).roundOut(); } |
| |
| SkIRect RoundIn(SkRect r) { return r.makeOutset(kRoundEpsilon, kRoundEpsilon).roundIn(); } |
| |
| sk_sp<SkSpecialSurface> Context::makeSurface(const SkISize& size, |
| const SkSurfaceProps* props) const { |
| if (!props) { |
| props = &fInfo.fSurfaceProps; |
| } |
| |
| SkImageInfo imageInfo = SkImageInfo::Make(size, |
| fInfo.fColorType, |
| kPremul_SkAlphaType, |
| sk_ref_sp(fInfo.fColorSpace)); |
| |
| #if defined(SK_GANESH) |
| if (fGaneshContext) { |
| // FIXME: Context should also store a surface origin that matches the source origin |
| return SkSpecialSurface::MakeRenderTarget(fGaneshContext, |
| imageInfo, |
| *props, |
| fGaneshOrigin); |
| } else |
| #endif |
| #if defined(SK_GRAPHITE) |
| if (fGraphiteRecorder) { |
| return SkSpecialSurface::MakeGraphite(fGraphiteRecorder, imageInfo, *props); |
| } else |
| #endif |
| { |
| return SkSpecialSurface::MakeRaster(imageInfo, *props); |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| // Mapping |
| |
| bool Mapping::decomposeCTM(const SkMatrix& ctm, const SkImageFilter* filter, |
| const skif::ParameterSpace<SkPoint>& representativePt) { |
| SkMatrix remainder, layer; |
| SkSize decomposed; |
| using MatrixCapability = SkImageFilter_Base::MatrixCapability; |
| MatrixCapability capability = |
| filter ? as_IFB(filter)->getCTMCapability() : MatrixCapability::kComplex; |
| if (capability == MatrixCapability::kTranslate) { |
| // Apply the entire CTM post-filtering |
| remainder = ctm; |
| layer = SkMatrix::I(); |
| } else if (ctm.isScaleTranslate() || capability == MatrixCapability::kComplex) { |
| // Either layer space can be anything (kComplex) - or - it can be scale+translate, and the |
| // ctm is. In both cases, the layer space can be equivalent to device space. |
| remainder = SkMatrix::I(); |
| layer = ctm; |
| } else if (ctm.decomposeScale(&decomposed, &remainder)) { |
| // This case implies some amount of sampling post-filtering, either due to skew or rotation |
| // in the original matrix. As such, keep the layer matrix as simple as possible. |
| layer = SkMatrix::Scale(decomposed.fWidth, decomposed.fHeight); |
| } else { |
| // Perspective, which has a non-uniform scaling effect on the filter. Pick a single scale |
| // factor that best matches where the filter will be evaluated. |
| SkScalar scale = SkMatrixPriv::DifferentialAreaScale(ctm, SkPoint(representativePt)); |
| if (SkScalarIsFinite(scale) && !SkScalarNearlyZero(scale)) { |
| // Now take the sqrt to go from an area scale factor to a scaling per X and Y |
| // FIXME: It would be nice to be able to choose a non-uniform scale. |
| scale = SkScalarSqrt(scale); |
| } else { |
| // The representative point was behind the W = 0 plane, so don't factor out any scale. |
| // NOTE: This makes remainder and layer the same as the MatrixCapability::Translate case |
| scale = 1.f; |
| } |
| |
| remainder = ctm; |
| remainder.preScale(SkScalarInvert(scale), SkScalarInvert(scale)); |
| layer = SkMatrix::Scale(scale, scale); |
| } |
| |
| SkMatrix invRemainder; |
| if (!remainder.invert(&invRemainder)) { |
| // Under floating point arithmetic, it's possible to decompose an invertible matrix into |
| // a scaling matrix and a remainder and have the remainder be non-invertible. Generally |
| // when this happens the scale factors are so large and the matrix so ill-conditioned that |
| // it's unlikely that any drawing would be reasonable, so failing to make a layer is okay. |
| return false; |
| } else { |
| fParamToLayerMatrix = layer; |
| fLayerToDevMatrix = remainder; |
| fDevToLayerMatrix = invRemainder; |
| return true; |
| } |
| } |
| |
| bool Mapping::adjustLayerSpace(const SkMatrix& layer) { |
| SkMatrix invLayer; |
| if (!layer.invert(&invLayer)) { |
| return false; |
| } |
| fParamToLayerMatrix.postConcat(layer); |
| fDevToLayerMatrix.postConcat(layer); |
| fLayerToDevMatrix.preConcat(invLayer); |
| return true; |
| } |
| |
| // Instantiate map specializations for the 6 geometric types used during filtering |
| template<> |
| SkRect Mapping::map<SkRect>(const SkRect& geom, const SkMatrix& matrix) { |
| return map_rect(matrix, geom); |
| } |
| |
| template<> |
| SkIRect Mapping::map<SkIRect>(const SkIRect& geom, const SkMatrix& matrix) { |
| return map_rect(matrix, geom); |
| } |
| |
| template<> |
| SkIPoint Mapping::map<SkIPoint>(const SkIPoint& geom, const SkMatrix& matrix) { |
| SkPoint p = SkPoint::Make(SkIntToScalar(geom.fX), SkIntToScalar(geom.fY)); |
| matrix.mapPoints(&p, 1); |
| return SkIPoint::Make(SkScalarRoundToInt(p.fX), SkScalarRoundToInt(p.fY)); |
| } |
| |
| template<> |
| SkPoint Mapping::map<SkPoint>(const SkPoint& geom, const SkMatrix& matrix) { |
| SkPoint p; |
| matrix.mapPoints(&p, &geom, 1); |
| return p; |
| } |
| |
| template<> |
| IVector Mapping::map<IVector>(const IVector& geom, const SkMatrix& matrix) { |
| return IVector(map_as_vector(geom.fX, geom.fY, matrix)); |
| } |
| |
| template<> |
| Vector Mapping::map<Vector>(const Vector& geom, const SkMatrix& matrix) { |
| return Vector(map_as_vector(geom.fX, geom.fY, matrix)); |
| } |
| |
| template<> |
| SkISize Mapping::map<SkISize>(const SkISize& geom, const SkMatrix& matrix) { |
| SkIVector v = map_as_vector(geom.fWidth, geom.fHeight, matrix); |
| return SkISize::Make(v.fX, v.fY); |
| } |
| |
| template<> |
| SkSize Mapping::map<SkSize>(const SkSize& geom, const SkMatrix& matrix) { |
| SkVector v = map_as_vector(geom.fWidth, geom.fHeight, matrix); |
| return SkSize::Make(v.fX, v.fY); |
| } |
| |
| template<> |
| SkMatrix Mapping::map<SkMatrix>(const SkMatrix& m, const SkMatrix& matrix) { |
| // If 'matrix' maps from the C1 coord space to the C2 coord space, and 'm' is a transform that |
| // operates on, and outputs to, the C1 coord space, we want to return a new matrix that is |
| // equivalent to 'm' that operates on and outputs to C2. This is the same as mapping the input |
| // from C2 to C1 (matrix^-1), then transforming by 'm', and then mapping from C1 to C2 (matrix). |
| SkMatrix inv; |
| SkAssertResult(matrix.invert(&inv)); |
| inv.postConcat(m); |
| inv.postConcat(matrix); |
| return inv; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| // LayerSpace<T> |
| |
| LayerSpace<SkRect> LayerSpace<SkMatrix>::mapRect(const LayerSpace<SkRect>& r) const { |
| return LayerSpace<SkRect>(map_rect(fData, SkRect(r))); |
| } |
| |
| LayerSpace<SkIRect> LayerSpace<SkMatrix>::mapRect(const LayerSpace<SkIRect>& r) const { |
| return LayerSpace<SkIRect>(map_rect(fData, SkIRect(r))); |
| } |
| |
| bool LayerSpace<SkMatrix>::inverseMapRect(const LayerSpace<SkRect>& r, |
| LayerSpace<SkRect>* out) const { |
| SkRect mapped; |
| if (inverse_map_rect(fData, SkRect(r), &mapped)) { |
| *out = LayerSpace<SkRect>(mapped); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| bool LayerSpace<SkMatrix>::inverseMapRect(const LayerSpace<SkIRect>& r, |
| LayerSpace<SkIRect>* out) const { |
| SkIRect mapped; |
| if (inverse_map_rect(fData, SkIRect(r), &mapped)) { |
| *out = LayerSpace<SkIRect>(mapped); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| // FilterResult |
| |
| sk_sp<SkSpecialImage> FilterResult::imageAndOffset(const Context& ctx, SkIPoint* offset) const { |
| auto [image, origin] = this->resolve(ctx, fLayerBounds); |
| *offset = SkIPoint(origin); |
| return image; |
| } |
| |
| bool FilterResult::isCropped(const LayerSpace<SkMatrix>& xtraTransform, |
| const LayerSpace<SkIRect>& dstBounds) const { |
| // Tiling and color-filtering can completely fill 'fLayerBounds' in which case its edge is |
| // a transition from possibly non-transparent to definitely transparent color. |
| bool fillsLayerBounds = fills_layer_bounds(fColorFilter.get()); |
| if (!fillsLayerBounds) { |
| // When that's not the case, 'fLayerBounds' may still be important if it crops the |
| // edges of the original transformed image itself. |
| LayerSpace<SkIRect> imageBounds = fTransform.mapRect( |
| LayerSpace<SkIRect>{SkIRect::MakeWH(fImage->width(), fImage->height())}); |
| fillsLayerBounds = !fLayerBounds.contains(imageBounds); |
| } |
| |
| if (fillsLayerBounds) { |
| // Some content (either the image itself, or tiling/color-filtering) can produce |
| // non-transparent output beyond 'fLayerBounds'. 'fLayerBounds' can only be ignored if the |
| // desired output is completely contained within it (i.e. the edges of 'fLayerBounds' are |
| // not visible). |
| // NOTE: For the identity transform, this is equal to !fLayerBounds.contains(dstBounds) |
| return !SkRectPriv::QuadContainsRect(SkMatrix(xtraTransform), |
| SkIRect(fLayerBounds), |
| SkIRect(dstBounds)); |
| } else { |
| // No part of the sampled and color-filtered image would produce non-transparent pixels |
| // outside of 'fLayerBounds' so 'fLayerBounds' can be ignored. |
| return false; |
| } |
| } |
| |
| FilterResult FilterResult::applyCrop(const Context& ctx, |
| const LayerSpace<SkIRect>& crop) const { |
| LayerSpace<SkIRect> tightBounds = crop; |
| // TODO(michaelludwig): Intersecting to the target output is only valid when the crop has |
| // decal tiling (the only current option). |
| if (!fImage || |
| !tightBounds.intersect(ctx.desiredOutput()) || |
| !tightBounds.intersect(fLayerBounds)) { |
| // The desired output would be filled with transparent black. There should never be a |
| // color filter acting on an empty image that could change that assumption. |
| SkASSERT(fImage || !fColorFilter); |
| return {}; |
| } |
| |
| LayerSpace<SkIPoint> origin; |
| if (!fills_layer_bounds(fColorFilter.get()) && |
| is_nearly_integer_translation(fTransform, &origin)) { |
| // We can lift the crop to earlier in the order of operations and apply it to the image |
| // subset directly. This does not rely on resolve() to call extract_subset() because it |
| // will still render a new image if there's a color filter. As such, we have to preserve |
| // the current color filter on the new FilterResult. |
| // NOTE: Even though applying a crop never renders a new image, moving the crop into the |
| // image dimensions allows future operations like applying a transform or color filter to |
| // be composed without rendering a new image since there is no longer an intervening crop. |
| FilterResult restrictedOutput = extract_subset(fImage.get(), origin, tightBounds); |
| restrictedOutput.fColorFilter = fColorFilter; |
| return restrictedOutput; |
| } else { |
| // Otherwise cropping is the final operation to the FilterResult's image and can always be |
| // applied by adjusting the layer bounds. |
| FilterResult restrictedOutput = *this; |
| restrictedOutput.fLayerBounds = tightBounds; |
| return restrictedOutput; |
| } |
| } |
| |
| FilterResult FilterResult::applyColorFilter(const Context& ctx, |
| sk_sp<SkColorFilter> colorFilter) const { |
| static const LayerSpace<SkMatrix> kIdentity{SkMatrix::I()}; |
| |
| // A null filter is the identity, so it should have been caught during image filter DAG creation |
| SkASSERT(colorFilter); |
| |
| // Color filters are applied after the transform and image sampling, but before the fLayerBounds |
| // crop. We can compose 'colorFilter' with any previously applied color filter regardless |
| // of the transform/sample state, so long as it respects the effect of the current crop. |
| LayerSpace<SkIRect> newLayerBounds = fLayerBounds; |
| if (as_CFB(colorFilter)->affectsTransparentBlack()) { |
| if (!fImage || !newLayerBounds.intersect(ctx.desiredOutput())) { |
| // The current image's intersection with the desired output is fully transparent, but |
| // the new color filter converts that into a non-transparent color. The desired output |
| // is filled with this color. |
| // TODO: When kClamp is supported, we can allocate a smaller surface |
| sk_sp<SkSpecialSurface> surface = ctx.makeSurface(SkISize(ctx.desiredOutput().size())); |
| if (!surface) { |
| return {}; |
| } |
| |
| SkPaint paint; |
| paint.setColor4f(SkColors::kTransparent, /*colorSpace=*/nullptr); |
| paint.setColorFilter(std::move(colorFilter)); |
| surface->getCanvas()->drawPaint(paint); |
| return {surface->makeImageSnapshot(), ctx.desiredOutput().topLeft()}; |
| } |
| |
| if (this->isCropped(kIdentity, ctx.desiredOutput())) { |
| // Since 'colorFilter' modifies transparent black, the new result's layer bounds must |
| // be the desired output. But if the current image is cropped we need to resolve the |
| // image to avoid losing the effect of the current 'fLayerBounds'. |
| FilterResult filtered = this->resolve(ctx, ctx.desiredOutput()); |
| return filtered.applyColorFilter(ctx, std::move(colorFilter)); |
| } |
| |
| // otherwise we can fill out to the desired output without worrying about losing the crop. |
| newLayerBounds = ctx.desiredOutput(); |
| } else { |
| if (!fImage || !newLayerBounds.intersect(ctx.desiredOutput())) { |
| // The color filter does not modify transparent black, so it remains transparent |
| return {}; |
| } |
| // otherwise a non-transparent affecting color filter can always be lifted before any crop |
| // because it does not change the "shape" of the prior FilterResult. |
| } |
| |
| // If we got here we can compose the new color filter with the previous filter and the prior |
| // layer bounds are either soft-cropped to the desired output, or we fill out the desired output |
| // when the new color filter affects transparent black. We don't check if the entire composed |
| // filter affects transparent black because earlier floods are restricted by the layer bounds. |
| FilterResult filtered = *this; |
| filtered.fLayerBounds = newLayerBounds; |
| filtered.fColorFilter = SkColorFilters::Compose(std::move(colorFilter), fColorFilter); |
| return filtered; |
| } |
| |
| static bool compatible_sampling(const SkSamplingOptions& currentSampling, |
| bool currentXformWontAffectNearest, |
| SkSamplingOptions* nextSampling, |
| bool nextXformWontAffectNearest) { |
| // Both transforms could perform non-trivial sampling, but if they are similar enough we |
| // assume performing one non-trivial sampling operation with the concatenated transform will |
| // not be visually distinguishable from sampling twice. |
| // TODO(michaelludwig): For now ignore mipmap policy, SkSpecialImages are not supposed to be |
| // drawn with mipmapping, and the majority of filter steps produce images that are at the |
| // proper scale and do not define mip levels. The main exception is the ::Image() filter |
| // leaf but that doesn't use this system yet. |
| if (currentSampling.isAniso() && nextSampling->isAniso()) { |
| // Assume we can get away with one sampling at the highest anisotropy level |
| *nextSampling = SkSamplingOptions::Aniso(std::max(currentSampling.maxAniso, |
| nextSampling->maxAniso)); |
| return true; |
| } else if (currentSampling.isAniso() && nextSampling->filter == SkFilterMode::kLinear) { |
| // Assume we can get away with the current anisotropic filter since the next is linear |
| *nextSampling = currentSampling; |
| return true; |
| } else if (nextSampling->isAniso() && currentSampling.filter == SkFilterMode::kLinear) { |
| // Mirror of the above, assume we can just get away with next's anisotropic filter |
| return true; |
| } else if (currentSampling.useCubic && (nextSampling->filter == SkFilterMode::kLinear || |
| (nextSampling->useCubic && |
| currentSampling.cubic.B == nextSampling->cubic.B && |
| currentSampling.cubic.C == nextSampling->cubic.C))) { |
| // Assume we can get away with the current bicubic filter, since the next is the same |
| // or a bilerp that can be upgraded. |
| *nextSampling = currentSampling; |
| return true; |
| } else if (nextSampling->useCubic && currentSampling.filter == SkFilterMode::kLinear) { |
| // Mirror of the above, assume we can just get away with next's cubic resampler |
| return true; |
| } else if (currentSampling.filter == SkFilterMode::kLinear && |
| nextSampling->filter == SkFilterMode::kLinear) { |
| // Assume we can get away with a single bilerp vs. the two |
| return true; |
| } else if (nextSampling->filter == SkFilterMode::kNearest && currentXformWontAffectNearest) { |
| // The next transform and nearest-neighbor filtering isn't impacted by the current transform |
| SkASSERT(currentSampling.filter == SkFilterMode::kLinear); |
| return true; |
| } else if (currentSampling.filter == SkFilterMode::kNearest && nextXformWontAffectNearest) { |
| // The next transform doesn't change the nearest-neighbor filtering of the current transform |
| SkASSERT(nextSampling->filter == SkFilterMode::kLinear); |
| *nextSampling = currentSampling; |
| return true; |
| } else { |
| // The current or next sampling is nearest neighbor, and will produce visible texels |
| // oriented with the current transform; assume this is a desired effect and preserve it. |
| return false; |
| } |
| } |
| |
| FilterResult FilterResult::applyTransform(const Context& ctx, |
| const LayerSpace<SkMatrix> &transform, |
| const SkSamplingOptions &sampling) const { |
| if (!fImage) { |
| // Transformed transparent black remains transparent black. |
| SkASSERT(!fColorFilter); |
| return {}; |
| } |
| |
| // Extract the sampling options that matter based on the current and next transforms. |
| // We make sure the new sampling is bilerp (default) if the new transform doesn't matter |
| // (and assert that the current is bilerp if its transform didn't matter). Bilerp can be |
| // maximally combined, so simplifies the logic in compatible_sampling(). |
| const bool currentXformIsInteger = is_nearly_integer_translation(fTransform); |
| const bool nextXformIsInteger = is_nearly_integer_translation(transform); |
| |
| SkASSERT(!currentXformIsInteger || fSamplingOptions == kDefaultSampling); |
| SkSamplingOptions nextSampling = nextXformIsInteger ? kDefaultSampling : sampling; |
| |
| // Determine if the image is being visibly cropped by the layer bounds, in which case we can't |
| // merge this transform with any previous transform (unless the new transform is an integer |
| // translation in which case any visible edge is aligned with the desired output and can be |
| // resolved by intersecting the transformed layer bounds and the output bounds). |
| bool isCropped = !nextXformIsInteger && this->isCropped(transform, ctx.desiredOutput()); |
| |
| FilterResult transformed; |
| if (!isCropped && compatible_sampling(fSamplingOptions, currentXformIsInteger, |
| &nextSampling, nextXformIsInteger)) { |
| // We can concat transforms and 'nextSampling' will be either fSamplingOptions, |
| // sampling, or a merged combination depending on the two transforms in play. |
| transformed = *this; |
| } else { |
| // We'll have to resolve this FilterResult first before 'transform' and 'sampling' can be |
| // correctly evaluated. 'nextSampling' will always be 'sampling'. |
| LayerSpace<SkIRect> tightBounds; |
| if (transform.inverseMapRect(ctx.desiredOutput(), &tightBounds)) { |
| transformed = this->resolve(ctx, tightBounds); |
| } |
| |
| if (!transformed.fImage) { |
| // Transform not invertible or resolve failed to create an image |
| return {}; |
| } |
| } |
| |
| transformed.fSamplingOptions = nextSampling; |
| transformed.fTransform.postConcat(transform); |
| // Rebuild the layer bounds and then restrict to the current desired output. The original value |
| // of fLayerBounds includes the image mapped by the original fTransform as well as any |
| // accumulated soft crops from desired outputs of prior stages. To prevent discarding that info, |
| // we map fLayerBounds by the additional transform, instead of re-mapping the image bounds. |
| transformed.fLayerBounds = transform.mapRect(transformed.fLayerBounds); |
| if (!transformed.fLayerBounds.intersect(ctx.desiredOutput())) { |
| // The transformed output doesn't touch the desired, so it would just be transparent black. |
| // TODO: This intersection only applies when the tile mode is kDecal. |
| return {}; |
| } |
| |
| return transformed; |
| } |
| |
| std::pair<sk_sp<SkSpecialImage>, LayerSpace<SkIPoint>> FilterResult::resolve( |
| const Context& ctx, |
| LayerSpace<SkIRect> dstBounds) const { |
| // The layer bounds is the final clip, so it can always be used to restrict 'dstBounds'. Even |
| // if there's a non-decal tile mode or transparent-black affecting color filter, those floods |
| // are restricted to fLayerBounds. |
| if (!fImage || !dstBounds.intersect(fLayerBounds)) { |
| return {nullptr, {}}; |
| } |
| |
| // If we have any extra effect to apply, there's no point in trying to extract a subset. |
| // TODO: Also factor in a non-decal tile mode |
| const bool subsetCompatible = !fColorFilter; |
| |
| // TODO(michaelludwig): If we get to the point where all filter results track bounds in |
| // floating point, then we can extend this case to any S+T transform. |
| LayerSpace<SkIPoint> origin; |
| if (subsetCompatible && is_nearly_integer_translation(fTransform, &origin)) { |
| return extract_subset(fImage.get(), origin, dstBounds); |
| } // else fall through and attempt a draw |
| |
| // Don't use context properties to avoid DMSAA on internal stages of filter evaluation. |
| SkSurfaceProps props = {}; |
| AutoSurface surface{ctx, dstBounds, /*renderInParameterSpace=*/false, &props}; |
| if (surface) { |
| this->draw(surface.canvas()); |
| } |
| return surface.snap(); |
| } |
| |
| void FilterResult::draw(SkCanvas* canvas) const { |
| if (!fImage) { |
| return; |
| } |
| |
| // When this is called by resolve(), the surface and canvas matrix are such that this clip is |
| // trivially a no-op, but including the clip means draw() works correctly in other scenarios. |
| canvas->clipIRect(SkIRect(fLayerBounds)); |
| |
| SkPaint paint; |
| paint.setAntiAlias(true); |
| paint.setBlendMode(SkBlendMode::kSrcOver); |
| paint.setColorFilter(fColorFilter); |
| |
| canvas->concat(SkMatrix(fTransform)); // src's origin is embedded in fTransform |
| |
| // If we are an integer translate, the default bilinear sampling *should* be equivalent to |
| // nearest-neighbor. Going through the direct image-drawing path tends to detect this |
| // and reduce sampling automatically. When we have to use an image shader, this isn't |
| // detected and some GPUs' linear filtering doesn't exactly match nearest-neighbor and can |
| // lead to leaks beyond the image's subset. Detect and reduce sampling explicitly. |
| SkSamplingOptions sampling = fSamplingOptions; |
| if (sampling == kDefaultSampling && is_nearly_integer_translation(fTransform)) { |
| sampling = {}; |
| } |
| |
| if (fills_layer_bounds(fColorFilter.get())) { |
| paint.setShader(fImage->asShader(SkTileMode::kDecal, sampling, SkMatrix::I())); |
| canvas->drawPaint(paint); |
| } else { |
| fImage->draw(canvas, 0.f, 0.f, sampling, &paint); |
| } |
| } |
| |
| sk_sp<SkShader> FilterResult::asShader(const Context& ctx, |
| const SkSamplingOptions& xtraSampling, |
| SkEnumBitMask<ShaderFlags> flags) const { |
| if (!fImage) { |
| return nullptr; |
| } |
| // Even if flags don't force resolving the filter result to an axis-aligned image, if the |
| // extra sampling to be applied is not compatible with the accumulated transform and sampling, |
| // or if the logical image is cropped by the layer bounds, the FilterResult will need to be |
| // resolved to an image before we wrap it as an SkShader. When checking if cropped, we use the |
| // FilterResult's layer bounds instead of the context's desired output, assuming that the layer |
| // bounds reflect the bounds of the coords a parent shader will pass to eval(). |
| const bool currentXformIsInteger = is_nearly_integer_translation(fTransform); |
| const bool nextXformIsInteger = |
| !(flags & ShaderFlags::kNonLinearSampling) && |
| (!(flags & ShaderFlags::kSampleInParameterSpace) || |
| is_nearly_integer_translation(LayerSpace<SkMatrix>(ctx.mapping().layerMatrix()))); |
| |
| SkSamplingOptions sampling = xtraSampling; |
| const bool needsResolve = |
| flags & ShaderFlags::kForceResolveInputs || |
| !compatible_sampling(fSamplingOptions, currentXformIsInteger, |
| &sampling, nextXformIsInteger) || |
| this->isCropped(LayerSpace<SkMatrix>(SkMatrix::I()), fLayerBounds); |
| |
| // Downgrade to nearest-neighbor if the sequence of sampling doesn't do anything |
| if (sampling == kDefaultSampling && nextXformIsInteger && |
| (needsResolve || currentXformIsInteger)) { |
| sampling = {}; |
| } |
| |
| sk_sp<SkShader> shader; |
| if (needsResolve) { |
| // The resolve takes care of fTransform (sans origin), fColorFilter, and fLayerBounds |
| auto [pixels, origin] = this->resolve(ctx, fLayerBounds); |
| if (pixels) { |
| shader = pixels->asShader(SkTileMode::kDecal, sampling, |
| SkMatrix::Translate(origin.x(), origin.y())); |
| } |
| } else { |
| // Since we didn't need to resolve, we know the content being sampled isn't cropped by |
| // fLayerBounds. fTransform and fColorFilter are handled in the shader directly. |
| shader = fImage->asShader(SkTileMode::kDecal, sampling, SkMatrix(fTransform)); |
| if (shader && fColorFilter) { |
| shader = shader->makeWithColorFilter(fColorFilter); |
| } |
| } |
| |
| if (shader && (flags & ShaderFlags::kSampleInParameterSpace)) { |
| // The FilterResult is meant to be sampled in layer space, but the shader this is feeding |
| // into is being sampled in parameter space. Add the inverse of the layerMatrix() (i.e. |
| // layer to parameter space) as a local matrix to convert from the parameter-space coords |
| // of the outer shader to the layer-space coords of the FilterResult). |
| SkMatrix layerToParam; |
| if (!ctx.mapping().layerMatrix().invert(&layerToParam)) { |
| return nullptr; |
| } |
| shader = shader->makeWithLocalMatrix(layerToParam); |
| } |
| |
| return shader; |
| } |
| |
| FilterResult FilterResult::MakeFromPicture(const Context& ctx, |
| sk_sp<SkPicture> pic, |
| ParameterSpace<SkRect> cullRect) { |
| if (!pic) { |
| return {}; |
| } |
| |
| LayerSpace<SkIRect> dstBounds = ctx.mapping().paramToLayer(cullRect).roundOut(); |
| if (!dstBounds.intersect(ctx.desiredOutput())) { |
| return {}; |
| } |
| |
| // Given the standard usage of the picture image filter (i.e., to render content at a fixed |
| // resolution that, most likely, differs from the screen's) disable LCD text by removing any |
| // knowledge of the pixel geometry. |
| // TODO: Should we just generally do this for layers with image filters? Or can we preserve it |
| // for layers that are still axis-aligned? |
| SkSurfaceProps props = ctx.surfaceProps().cloneWithPixelGeometry(kUnknown_SkPixelGeometry); |
| AutoSurface surface{ctx, dstBounds, /*renderInParameterSpace=*/true, &props}; |
| if (surface) { |
| surface->clipRect(SkRect(cullRect)); |
| surface->drawPicture(std::move(pic)); |
| } |
| return surface.snap(); |
| } |
| |
| FilterResult FilterResult::MakeFromShader(const Context& ctx, |
| sk_sp<SkShader> shader, |
| bool dither) { |
| if (!shader) { |
| return {}; |
| } |
| |
| AutoSurface surface{ctx, ctx.desiredOutput(), /*renderInParameterSpace=*/true}; |
| if (surface) { |
| SkPaint paint; |
| paint.setShader(shader); |
| paint.setDither(dither); |
| surface->drawPaint(paint); |
| } |
| return surface.snap(); |
| } |
| |
| FilterResult FilterResult::MakeFromImage(const Context& ctx, |
| sk_sp<SkImage> image, |
| const SkRect& srcRect, |
| const ParameterSpace<SkRect>& dstRect, |
| const SkSamplingOptions& sampling) { |
| if (!image) { |
| return {}; |
| } |
| |
| // Check for direct conversion to an SkSpecialImage and then FilterResult. Eventually this |
| // whole function should be replaceable with: |
| // FilterResult(fImage, fSrcRect, fDstRect).applyTransform(mapping.layerMatrix(), fSampling); |
| SkIRect srcSubset = RoundOut(srcRect); |
| if (SkRect::Make(srcSubset) == srcRect) { |
| // Construct an SkSpecialImage from the subset directly instead of drawing. |
| auto specialImage = SkSpecialImage::MakeFromImage( |
| ctx.getContext(), srcSubset, std::move(image), ctx.surfaceProps()); |
| |
| // Treat the srcRect's top left as "layer" space since we are folding the src->dst transform |
| // and the param->layer transform into a single transform step. |
| skif::FilterResult subset{std::move(specialImage), |
| skif::LayerSpace<SkIPoint>(srcSubset.topLeft())}; |
| SkMatrix transform = SkMatrix::Concat(ctx.mapping().layerMatrix(), |
| SkMatrix::RectToRect(srcRect, SkRect(dstRect))); |
| return subset.applyTransform(ctx, skif::LayerSpace<SkMatrix>(transform), sampling); |
| } |
| |
| // For now, draw the src->dst subset of image into a new image. |
| LayerSpace<SkIRect> dstBounds = ctx.mapping().paramToLayer(dstRect).roundOut(); |
| if (!dstBounds.intersect(ctx.desiredOutput())) { |
| return {}; |
| } |
| |
| AutoSurface surface{ctx, dstBounds, /*renderInParameterSpace=*/true}; |
| if (surface) { |
| SkPaint paint; |
| paint.setAntiAlias(true); |
| surface->drawImageRect(image, srcRect, SkRect(dstRect), sampling, &paint, |
| SkCanvas::kStrict_SrcRectConstraint); |
| } |
| return surface.snap(); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| // FilterResult::Builder |
| |
| FilterResult::Builder::Builder(const Context& context) : fContext(context) {} |
| FilterResult::Builder::~Builder() = default; |
| |
| SkSpan<sk_sp<SkShader>> FilterResult::Builder::createInputShaders( |
| SkEnumBitMask<ShaderFlags> flags, |
| const SkSamplingOptions& sampling) { |
| fInputShaders.reserve(fInputs.size()); |
| for (const FilterResult& input : fInputs) { |
| fInputShaders.push_back(input.asShader(fContext, sampling, flags)); |
| } |
| return SkSpan<sk_sp<SkShader>>(fInputShaders); |
| } |
| |
| LayerSpace<SkIRect> FilterResult::Builder::outputBounds(SkEnumBitMask<ShaderFlags> flags) const { |
| LayerSpace<SkIRect> output = LayerSpace<SkIRect>::Empty(); |
| if (flags & ShaderFlags::kOutputFillsInputUnion) { |
| // The union of all inputs' layer bounds |
| if (fInputs.size() > 0) { |
| output = fInputs[0].layerBounds(); |
| for (int i = 1; i < fInputs.size(); ++i) { |
| output.join(fInputs[i].layerBounds()); |
| } |
| } |
| } else { |
| // Pessimistically assume output fills the full desired bounds |
| output = fContext.desiredOutput(); |
| } |
| |
| // Intersect against desired output now since a Builder never has to produce an image larger |
| // than its context's desired output. |
| if (!output.intersect(fContext.desiredOutput())) { |
| return LayerSpace<SkIRect>::Empty(); |
| } |
| return output; |
| } |
| |
| FilterResult FilterResult::Builder::drawShader(sk_sp<SkShader> shader, |
| SkEnumBitMask<ShaderFlags> flags, |
| const LayerSpace<SkIRect>& outputBounds) const { |
| SkASSERT(!outputBounds.isEmpty()); // Should have been rejected before we created shaders |
| if (!shader) { |
| return {}; |
| } |
| |
| AutoSurface surface{fContext, outputBounds, flags & ShaderFlags::kSampleInParameterSpace}; |
| if (surface) { |
| SkPaint paint; |
| paint.setShader(std::move(shader)); |
| surface->drawPaint(paint); |
| } |
| return surface.snap(); |
| } |
| |
| FilterResult FilterResult::Builder::merge() { |
| if (fInputs.empty()) { |
| return {}; |
| } else if (fInputs.size() == 1) { |
| return fInputs[0]; |
| } |
| |
| const LayerSpace<SkIRect> outputBounds = |
| this->outputBounds(ShaderFlags::kOutputFillsInputUnion); |
| AutoSurface surface{fContext, outputBounds, /*renderInParameterSpace=*/false}; |
| if (surface) { |
| for (const FilterResult& input : fInputs) { |
| surface->save(); |
| input.draw(surface.canvas()); |
| surface->restore(); |
| } |
| } |
| return surface.snap(); |
| } |
| |
| } // end namespace skif |
