| /* |
| * 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 "src/core/SkGpuBlurUtils.h" |
| |
| #include "include/core/SkBitmap.h" |
| #include "include/core/SkRect.h" |
| |
| #if SK_SUPPORT_GPU |
| #include "include/gpu/GrRecordingContext.h" |
| #include "src/gpu/GrCaps.h" |
| #include "src/gpu/GrRecordingContextPriv.h" |
| #include "src/gpu/SkGr.h" |
| #include "src/gpu/effects/GrGaussianConvolutionFragmentProcessor.h" |
| #include "src/gpu/effects/GrMatrixConvolutionEffect.h" |
| #include "src/gpu/effects/GrTextureEffect.h" |
| |
| #if SK_GPU_V1 |
| |
| using Direction = GrGaussianConvolutionFragmentProcessor::Direction; |
| |
| static void fill_in_2D_gaussian_kernel(float* kernel, int width, int height, |
| SkScalar sigmaX, SkScalar sigmaY) { |
| const float twoSigmaSqrdX = 2.0f * SkScalarToFloat(SkScalarSquare(sigmaX)); |
| const float twoSigmaSqrdY = 2.0f * SkScalarToFloat(SkScalarSquare(sigmaY)); |
| |
| // SkGpuBlurUtils::GaussianBlur() should have detected the cases where a 2D blur |
| // degenerates to a 1D on X or Y, or to the identity. |
| SkASSERT(!SkGpuBlurUtils::IsEffectivelyZeroSigma(sigmaX) && |
| !SkGpuBlurUtils::IsEffectivelyZeroSigma(sigmaY)); |
| SkASSERT(!SkScalarNearlyZero(twoSigmaSqrdX) && !SkScalarNearlyZero(twoSigmaSqrdY)); |
| |
| const float sigmaXDenom = 1.0f / twoSigmaSqrdX; |
| const float sigmaYDenom = 1.0f / twoSigmaSqrdY; |
| const int xRadius = width / 2; |
| const int yRadius = height / 2; |
| |
| float sum = 0.0f; |
| for (int x = 0; x < width; x++) { |
| float xTerm = static_cast<float>(x - xRadius); |
| xTerm = xTerm * xTerm * sigmaXDenom; |
| for (int y = 0; y < height; y++) { |
| float yTerm = static_cast<float>(y - yRadius); |
| float xyTerm = sk_float_exp(-(xTerm + yTerm * yTerm * sigmaYDenom)); |
| // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian |
| // is dropped here, since we renormalize the kernel below. |
| kernel[y * width + x] = xyTerm; |
| sum += xyTerm; |
| } |
| } |
| // Normalize the kernel |
| float scale = 1.0f / sum; |
| for (int i = 0; i < width * height; ++i) { |
| kernel[i] *= scale; |
| } |
| } |
| |
| /** |
| * Draws 'dstRect' into 'surfaceFillContext' evaluating a 1D Gaussian over 'srcView'. The src rect |
| * is 'dstRect' offset by 'dstToSrcOffset'. 'mode' and 'bounds' are applied to the src coords. |
| */ |
| static void convolve_gaussian_1d(GrSurfaceFillContext* sfc, |
| GrSurfaceProxyView srcView, |
| const SkIRect srcSubset, |
| SkIVector dstToSrcOffset, |
| const SkIRect& dstRect, |
| SkAlphaType srcAlphaType, |
| Direction direction, |
| int radius, |
| float sigma, |
| SkTileMode mode) { |
| SkASSERT(radius && !SkGpuBlurUtils::IsEffectivelyZeroSigma(sigma)); |
| auto wm = SkTileModeToWrapMode(mode); |
| auto srcRect = dstRect.makeOffset(dstToSrcOffset); |
| // NOTE: This could just be GrMatrixConvolutionEffect with one of the dimensions set to 1 |
| // and the appropriate kernel already computed, but there's value in keeping the shader simpler. |
| // TODO(michaelludwig): Is this true? If not, is the shader key simplicity worth it two have |
| // two convolution effects? |
| std::unique_ptr<GrFragmentProcessor> conv = |
| GrGaussianConvolutionFragmentProcessor::Make(std::move(srcView), |
| srcAlphaType, |
| direction, |
| radius, |
| sigma, |
| wm, |
| srcSubset, |
| &srcRect, |
| *sfc->caps()); |
| sfc->fillRectToRectWithFP(srcRect, dstRect, std::move(conv)); |
| } |
| |
| static std::unique_ptr<GrSurfaceDrawContext> convolve_gaussian_2d(GrRecordingContext* context, |
| GrSurfaceProxyView srcView, |
| GrColorType srcColorType, |
| const SkIRect& srcBounds, |
| const SkIRect& dstBounds, |
| int radiusX, |
| int radiusY, |
| SkScalar sigmaX, |
| SkScalar sigmaY, |
| SkTileMode mode, |
| sk_sp<SkColorSpace> finalCS, |
| SkBackingFit dstFit) { |
| SkASSERT(radiusX && radiusY); |
| SkASSERT(!SkGpuBlurUtils::IsEffectivelyZeroSigma(sigmaX) && |
| !SkGpuBlurUtils::IsEffectivelyZeroSigma(sigmaY)); |
| // Create the sdc with default SkSurfaceProps. Gaussian blurs will soon use a |
| // GrSurfaceFillContext, at which point the SkSurfaceProps won't exist anymore. |
| auto surfaceDrawContext = GrSurfaceDrawContext::Make( |
| context, srcColorType, std::move(finalCS), dstFit, dstBounds.size(), SkSurfaceProps(), |
| 1, GrMipmapped::kNo, srcView.proxy()->isProtected(), srcView.origin()); |
| if (!surfaceDrawContext) { |
| return nullptr; |
| } |
| |
| SkISize size = SkISize::Make(SkGpuBlurUtils::KernelWidth(radiusX), |
| SkGpuBlurUtils::KernelWidth(radiusY)); |
| SkIPoint kernelOffset = SkIPoint::Make(radiusX, radiusY); |
| GrPaint paint; |
| auto wm = SkTileModeToWrapMode(mode); |
| |
| // GaussianBlur() should have downsampled the request until we can handle the 2D blur with |
| // just a uniform array. |
| SkASSERT(size.area() <= GrMatrixConvolutionEffect::kMaxUniformSize); |
| float kernel[GrMatrixConvolutionEffect::kMaxUniformSize]; |
| fill_in_2D_gaussian_kernel(kernel, size.width(), size.height(), sigmaX, sigmaY); |
| auto conv = GrMatrixConvolutionEffect::Make(context, std::move(srcView), srcBounds, |
| size, kernel, 1.0f, 0.0f, kernelOffset, wm, true, |
| *surfaceDrawContext->caps()); |
| |
| paint.setColorFragmentProcessor(std::move(conv)); |
| paint.setPorterDuffXPFactory(SkBlendMode::kSrc); |
| |
| // 'dstBounds' is actually in 'srcView' proxy space. It represents the blurred area from src |
| // space that we want to capture in the new RTC at {0, 0}. Hence, we use its size as the rect to |
| // draw and it directly as the local rect. |
| surfaceDrawContext->fillRectToRect(nullptr, std::move(paint), GrAA::kNo, SkMatrix::I(), |
| SkRect::Make(dstBounds.size()), SkRect::Make(dstBounds)); |
| |
| return surfaceDrawContext; |
| } |
| |
| static std::unique_ptr<GrSurfaceDrawContext> convolve_gaussian(GrRecordingContext* context, |
| GrSurfaceProxyView srcView, |
| GrColorType srcColorType, |
| SkAlphaType srcAlphaType, |
| SkIRect srcBounds, |
| SkIRect dstBounds, |
| Direction direction, |
| int radius, |
| float sigma, |
| SkTileMode mode, |
| sk_sp<SkColorSpace> finalCS, |
| SkBackingFit fit) { |
| using namespace SkGpuBlurUtils; |
| SkASSERT(radius > 0 && !SkGpuBlurUtils::IsEffectivelyZeroSigma(sigma)); |
| // Logically we're creating an infinite blur of 'srcBounds' of 'srcView' with 'mode' tiling |
| // and then capturing the 'dstBounds' portion in a new RTC where the top left of 'dstBounds' is |
| // at {0, 0} in the new RTC. |
| // |
| // Create the sdc with default SkSurfaceProps. Gaussian blurs will soon use a |
| // GrSurfaceFillContext, at which point the SkSurfaceProps won't exist anymore. |
| auto dstSurfaceDrawContext = GrSurfaceDrawContext::Make( |
| context, srcColorType, std::move(finalCS), fit, dstBounds.size(), SkSurfaceProps(), 1, |
| GrMipmapped::kNo, srcView.proxy()->isProtected(), srcView.origin()); |
| if (!dstSurfaceDrawContext) { |
| return nullptr; |
| } |
| // This represents the translation from 'dstSurfaceDrawContext' coords to 'srcView' coords. |
| auto rtcToSrcOffset = dstBounds.topLeft(); |
| |
| auto srcBackingBounds = SkIRect::MakeSize(srcView.proxy()->backingStoreDimensions()); |
| // We've implemented splitting the dst bounds up into areas that do and do not need to |
| // use shader based tiling but only for some modes... |
| bool canSplit = mode == SkTileMode::kDecal || mode == SkTileMode::kClamp; |
| // ...but it's not worth doing the splitting if we'll get HW tiling instead of shader tiling. |
| bool canHWTile = |
| srcBounds.contains(srcBackingBounds) && |
| !context->priv().caps()->reducedShaderMode() && // this mode always uses shader tiling |
| !(mode == SkTileMode::kDecal && !context->priv().caps()->clampToBorderSupport()); |
| if (!canSplit || canHWTile) { |
| auto dstRect = SkIRect::MakeSize(dstBounds.size()); |
| convolve_gaussian_1d(dstSurfaceDrawContext.get(), std::move(srcView), srcBounds, |
| rtcToSrcOffset, dstRect, srcAlphaType, direction, radius, sigma, mode); |
| return dstSurfaceDrawContext; |
| } |
| |
| // 'left' and 'right' are the sub rects of 'srcBounds' where 'mode' must be enforced. |
| // 'mid' is the area where we can ignore the mode because the kernel does not reach to the |
| // edge of 'srcBounds'. |
| SkIRect mid, left, right; |
| // 'top' and 'bottom' are areas of 'dstBounds' that are entirely above/below 'srcBounds'. |
| // These are areas that we can simply clear in the dst in kDecal mode. If 'srcBounds' |
| // straddles the top edge of 'dstBounds' then 'top' will be inverted and we will skip |
| // processing for the rect. Similar for 'bottom'. The positional/directional labels above refer |
| // to the Direction::kX case and one should think of these as 'left' and 'right' for |
| // Direction::kY. |
| SkIRect top, bottom; |
| if (Direction::kX == direction) { |
| top = {dstBounds.left(), dstBounds.top() , dstBounds.right(), srcBounds.top() }; |
| bottom = {dstBounds.left(), srcBounds.bottom(), dstBounds.right(), dstBounds.bottom()}; |
| |
| // Inset for sub-rect of 'srcBounds' where the x-dir kernel doesn't reach the edges, clipped |
| // vertically to dstBounds. |
| int midA = std::max(srcBounds.top() , dstBounds.top() ); |
| int midB = std::min(srcBounds.bottom(), dstBounds.bottom()); |
| mid = {srcBounds.left() + radius, midA, srcBounds.right() - radius, midB}; |
| if (mid.isEmpty()) { |
| // There is no middle where the bounds can be ignored. Make the left span the whole |
| // width of dst and we will not draw mid or right. |
| left = {dstBounds.left(), mid.top(), dstBounds.right(), mid.bottom()}; |
| } else { |
| left = {dstBounds.left(), mid.top(), mid.left() , mid.bottom()}; |
| right = {mid.right(), mid.top(), dstBounds.right(), mid.bottom()}; |
| } |
| } else { |
| // This is the same as the x direction code if you turn your head 90 degrees CCW. Swap x and |
| // y and swap top/bottom with left/right. |
| top = {dstBounds.left(), dstBounds.top(), srcBounds.left() , dstBounds.bottom()}; |
| bottom = {srcBounds.right(), dstBounds.top(), dstBounds.right(), dstBounds.bottom()}; |
| |
| int midA = std::max(srcBounds.left() , dstBounds.left() ); |
| int midB = std::min(srcBounds.right(), dstBounds.right()); |
| mid = {midA, srcBounds.top() + radius, midB, srcBounds.bottom() - radius}; |
| |
| if (mid.isEmpty()) { |
| left = {mid.left(), dstBounds.top(), mid.right(), dstBounds.bottom()}; |
| } else { |
| left = {mid.left(), dstBounds.top(), mid.right(), mid.top() }; |
| right = {mid.left(), mid.bottom() , mid.right(), dstBounds.bottom()}; |
| } |
| } |
| |
| auto convolve = [&](SkIRect rect) { |
| // Transform rect into the render target's coord system. |
| rect.offset(-rtcToSrcOffset); |
| convolve_gaussian_1d(dstSurfaceDrawContext.get(), srcView, srcBounds, rtcToSrcOffset, rect, |
| srcAlphaType, direction, radius, sigma, mode); |
| }; |
| auto clear = [&](SkIRect rect) { |
| // Transform rect into the render target's coord system. |
| rect.offset(-rtcToSrcOffset); |
| dstSurfaceDrawContext->clearAtLeast(rect, SK_PMColor4fTRANSPARENT); |
| }; |
| |
| // Doing mid separately will cause two draws to occur (left and right batch together). At |
| // small sizes of mid it is worse to issue more draws than to just execute the slightly |
| // more complicated shader that implements the tile mode across mid. This threshold is |
| // very arbitrary right now. It is believed that a 21x44 mid on a Moto G4 is a significant |
| // regression compared to doing one draw but it has not been locally evaluated or tuned. |
| // The optimal cutoff is likely to vary by GPU. |
| if (!mid.isEmpty() && mid.width()*mid.height() < 256*256) { |
| left.join(mid); |
| left.join(right); |
| mid = SkIRect::MakeEmpty(); |
| right = SkIRect::MakeEmpty(); |
| // It's unknown whether for kDecal it'd be better to expand the draw rather than a draw and |
| // up to two clears. |
| if (mode == SkTileMode::kClamp) { |
| left.join(top); |
| left.join(bottom); |
| top = SkIRect::MakeEmpty(); |
| bottom = SkIRect::MakeEmpty(); |
| } |
| } |
| |
| if (!top.isEmpty()) { |
| if (mode == SkTileMode::kDecal) { |
| clear(top); |
| } else { |
| convolve(top); |
| } |
| } |
| |
| if (!bottom.isEmpty()) { |
| if (mode == SkTileMode::kDecal) { |
| clear(bottom); |
| } else { |
| convolve(bottom); |
| } |
| } |
| |
| if (mid.isEmpty()) { |
| convolve(left); |
| } else { |
| convolve(left); |
| convolve(right); |
| convolve(mid); |
| } |
| return dstSurfaceDrawContext; |
| } |
| |
| // Expand the contents of 'src' to fit in 'dstSize'. At this point, we are expanding an intermediate |
| // image, so there's no need to account for a proxy offset from the original input. |
| static std::unique_ptr<GrSurfaceDrawContext> reexpand(GrRecordingContext* context, |
| std::unique_ptr<GrSurfaceContext> src, |
| const SkRect& srcBounds, |
| SkISize dstSize, |
| sk_sp<SkColorSpace> colorSpace, |
| SkBackingFit fit) { |
| GrSurfaceProxyView srcView = src->readSurfaceView(); |
| if (!srcView.asTextureProxy()) { |
| return nullptr; |
| } |
| |
| GrColorType srcColorType = src->colorInfo().colorType(); |
| SkAlphaType srcAlphaType = src->colorInfo().alphaType(); |
| |
| src.reset(); // no longer needed |
| |
| // Create the sdc with default SkSurfaceProps. Gaussian blurs will soon use a |
| // GrSurfaceFillContext, at which point the SkSurfaceProps won't exist anymore. |
| auto dstSurfaceDrawContext = GrSurfaceDrawContext::Make( |
| context, srcColorType, std::move(colorSpace), fit, dstSize, SkSurfaceProps(), 1, |
| GrMipmapped::kNo, srcView.proxy()->isProtected(), srcView.origin()); |
| if (!dstSurfaceDrawContext) { |
| return nullptr; |
| } |
| |
| GrPaint paint; |
| auto fp = GrTextureEffect::MakeSubset(std::move(srcView), srcAlphaType, SkMatrix::I(), |
| GrSamplerState::Filter::kLinear, srcBounds, srcBounds, |
| *context->priv().caps()); |
| paint.setColorFragmentProcessor(std::move(fp)); |
| paint.setPorterDuffXPFactory(SkBlendMode::kSrc); |
| |
| dstSurfaceDrawContext->fillRectToRect(nullptr, std::move(paint), GrAA::kNo, SkMatrix::I(), |
| SkRect::Make(dstSize), srcBounds); |
| |
| return dstSurfaceDrawContext; |
| } |
| |
| static std::unique_ptr<GrSurfaceDrawContext> two_pass_gaussian(GrRecordingContext* context, |
| GrSurfaceProxyView srcView, |
| GrColorType srcColorType, |
| SkAlphaType srcAlphaType, |
| sk_sp<SkColorSpace> colorSpace, |
| SkIRect srcBounds, |
| SkIRect dstBounds, |
| float sigmaX, |
| float sigmaY, |
| int radiusX, |
| int radiusY, |
| SkTileMode mode, |
| SkBackingFit fit) { |
| SkASSERT(radiusX || radiusY); |
| std::unique_ptr<GrSurfaceDrawContext> dstSurfaceDrawContext; |
| if (radiusX > 0) { |
| SkBackingFit xFit = radiusY > 0 ? SkBackingFit::kApprox : fit; |
| // Expand the dstBounds vertically to produce necessary content for the y-pass. Then we will |
| // clip these in a tile-mode dependent way to ensure the tile-mode gets implemented |
| // correctly. However, if we're not going to do a y-pass then we must use the original |
| // dstBounds without clipping to produce the correct output size. |
| SkIRect xPassDstBounds = dstBounds; |
| if (radiusY) { |
| xPassDstBounds.outset(0, radiusY); |
| if (mode == SkTileMode::kRepeat || mode == SkTileMode::kMirror) { |
| int srcH = srcBounds.height(); |
| int srcTop = srcBounds.top(); |
| if (mode == SkTileMode::kMirror) { |
| srcTop -= srcH; |
| srcH *= 2; |
| } |
| |
| float floatH = srcH; |
| // First row above the dst rect where we should restart the tile mode. |
| int n = sk_float_floor2int_no_saturate((xPassDstBounds.top() - srcTop)/floatH); |
| int topClip = srcTop + n*srcH; |
| |
| // First row above below the dst rect where we should restart the tile mode. |
| n = sk_float_ceil2int_no_saturate( |
| (xPassDstBounds.bottom() - srcBounds.bottom())/floatH); |
| int bottomClip = srcBounds.bottom() + n*srcH; |
| |
| xPassDstBounds.fTop = std::max(xPassDstBounds.top(), topClip); |
| xPassDstBounds.fBottom = std::min(xPassDstBounds.bottom(), bottomClip); |
| } else { |
| if (xPassDstBounds.fBottom <= srcBounds.top()) { |
| if (mode == SkTileMode::kDecal) { |
| return nullptr; |
| } |
| xPassDstBounds.fTop = srcBounds.top(); |
| xPassDstBounds.fBottom = xPassDstBounds.fTop + 1; |
| } else if (xPassDstBounds.fTop >= srcBounds.bottom()) { |
| if (mode == SkTileMode::kDecal) { |
| return nullptr; |
| } |
| xPassDstBounds.fBottom = srcBounds.bottom(); |
| xPassDstBounds.fTop = xPassDstBounds.fBottom - 1; |
| } else { |
| xPassDstBounds.fTop = std::max(xPassDstBounds.fTop, srcBounds.top()); |
| xPassDstBounds.fBottom = std::min(xPassDstBounds.fBottom, srcBounds.bottom()); |
| } |
| int leftSrcEdge = srcBounds.fLeft - radiusX ; |
| int rightSrcEdge = srcBounds.fRight + radiusX; |
| if (mode == SkTileMode::kClamp) { |
| // In clamp the column just outside the src bounds has the same value as the |
| // column just inside, unlike decal. |
| leftSrcEdge += 1; |
| rightSrcEdge -= 1; |
| } |
| if (xPassDstBounds.fRight <= leftSrcEdge) { |
| if (mode == SkTileMode::kDecal) { |
| return nullptr; |
| } |
| xPassDstBounds.fLeft = xPassDstBounds.fRight - 1; |
| } else { |
| xPassDstBounds.fLeft = std::max(xPassDstBounds.fLeft, leftSrcEdge); |
| } |
| if (xPassDstBounds.fLeft >= rightSrcEdge) { |
| if (mode == SkTileMode::kDecal) { |
| return nullptr; |
| } |
| xPassDstBounds.fRight = xPassDstBounds.fLeft + 1; |
| } else { |
| xPassDstBounds.fRight = std::min(xPassDstBounds.fRight, rightSrcEdge); |
| } |
| } |
| } |
| dstSurfaceDrawContext = convolve_gaussian( |
| context, std::move(srcView), srcColorType, srcAlphaType, srcBounds, xPassDstBounds, |
| Direction::kX, radiusX, sigmaX, mode, colorSpace, xFit); |
| if (!dstSurfaceDrawContext) { |
| return nullptr; |
| } |
| srcView = dstSurfaceDrawContext->readSurfaceView(); |
| SkIVector newDstBoundsOffset = dstBounds.topLeft() - xPassDstBounds.topLeft(); |
| dstBounds = SkIRect::MakeSize(dstBounds.size()).makeOffset(newDstBoundsOffset); |
| srcBounds = SkIRect::MakeSize(xPassDstBounds.size()); |
| } |
| |
| if (!radiusY) { |
| return dstSurfaceDrawContext; |
| } |
| |
| return convolve_gaussian(context, std::move(srcView), srcColorType, srcAlphaType, srcBounds, |
| dstBounds, Direction::kY, radiusY, sigmaY, mode, colorSpace, fit); |
| } |
| #endif // SK_GPU_V1 |
| |
| namespace SkGpuBlurUtils { |
| |
| #if SK_GPU_V1 |
| std::unique_ptr<GrSurfaceDrawContext> GaussianBlur(GrRecordingContext* context, |
| GrSurfaceProxyView srcView, |
| GrColorType srcColorType, |
| SkAlphaType srcAlphaType, |
| sk_sp<SkColorSpace> colorSpace, |
| SkIRect dstBounds, |
| SkIRect srcBounds, |
| float sigmaX, |
| float sigmaY, |
| SkTileMode mode, |
| SkBackingFit fit) { |
| SkASSERT(context); |
| TRACE_EVENT2("skia.gpu", "GaussianBlur", "sigmaX", sigmaX, "sigmaY", sigmaY); |
| |
| if (!srcView.asTextureProxy()) { |
| return nullptr; |
| } |
| |
| int maxRenderTargetSize = context->priv().caps()->maxRenderTargetSize(); |
| if (dstBounds.width() > maxRenderTargetSize || dstBounds.height() > maxRenderTargetSize) { |
| return nullptr; |
| } |
| |
| int radiusX = SigmaRadius(sigmaX); |
| int radiusY = SigmaRadius(sigmaY); |
| // Attempt to reduce the srcBounds in order to detect that we can set the sigmas to zero or |
| // to reduce the amount of work to rescale the source if sigmas are large. TODO: Could consider |
| // how to minimize the required source bounds for repeat/mirror modes. |
| if (mode == SkTileMode::kClamp || mode == SkTileMode::kDecal) { |
| SkIRect reach = dstBounds.makeOutset(radiusX, radiusY); |
| SkIRect intersection; |
| if (!intersection.intersect(reach, srcBounds)) { |
| if (mode == SkTileMode::kDecal) { |
| return nullptr; |
| } else { |
| if (reach.fLeft >= srcBounds.fRight) { |
| srcBounds.fLeft = srcBounds.fRight - 1; |
| } else if (reach.fRight <= srcBounds.fLeft) { |
| srcBounds.fRight = srcBounds.fLeft + 1; |
| } |
| if (reach.fTop >= srcBounds.fBottom) { |
| srcBounds.fTop = srcBounds.fBottom - 1; |
| } else if (reach.fBottom <= srcBounds.fTop) { |
| srcBounds.fBottom = srcBounds.fTop + 1; |
| } |
| } |
| } else { |
| srcBounds = intersection; |
| } |
| } |
| |
| if (mode != SkTileMode::kDecal) { |
| // All non-decal tile modes are equivalent for one pixel width/height src and amount to a |
| // single color value repeated at each column/row. Applying the normalized kernel to that |
| // column/row yields that same color. So no blurring is necessary. |
| if (srcBounds.width() == 1) { |
| sigmaX = 0.f; |
| radiusX = 0; |
| } |
| if (srcBounds.height() == 1) { |
| sigmaY = 0.f; |
| radiusY = 0; |
| } |
| } |
| |
| // If we determined that there is no blurring necessary in either direction then just do a |
| // a draw that applies the tile mode. |
| if (!radiusX && !radiusY) { |
| // Create the sdc with default SkSurfaceProps. Gaussian blurs will soon use a |
| // GrSurfaceFillContext, at which point the SkSurfaceProps won't exist anymore. |
| auto result = GrSurfaceDrawContext::Make(context, srcColorType, std::move(colorSpace), fit, |
| dstBounds.size(), SkSurfaceProps(), 1, |
| GrMipmapped::kNo, |
| srcView.proxy()->isProtected(), srcView.origin()); |
| if (!result) { |
| return nullptr; |
| } |
| GrSamplerState sampler(SkTileModeToWrapMode(mode), GrSamplerState::Filter::kNearest); |
| auto fp = GrTextureEffect::MakeSubset(std::move(srcView), |
| srcAlphaType, |
| SkMatrix::I(), |
| sampler, |
| SkRect::Make(srcBounds), |
| SkRect::Make(dstBounds), |
| *context->priv().caps()); |
| result->fillRectToRectWithFP(dstBounds, SkIRect::MakeSize(dstBounds.size()), std::move(fp)); |
| return result; |
| } |
| |
| if (sigmaX <= kMaxSigma && sigmaY <= kMaxSigma) { |
| SkASSERT(radiusX <= GrGaussianConvolutionFragmentProcessor::kMaxKernelRadius); |
| SkASSERT(radiusY <= GrGaussianConvolutionFragmentProcessor::kMaxKernelRadius); |
| // For really small blurs (certainly no wider than 5x5 on desktop GPUs) it is faster to just |
| // launch a single non separable kernel vs two launches. |
| const int kernelSize = (2 * radiusX + 1) * (2 * radiusY + 1); |
| if (radiusX > 0 && radiusY > 0 && |
| kernelSize <= GrMatrixConvolutionEffect::kMaxUniformSize && |
| !context->priv().caps()->reducedShaderMode()) { |
| // Apply the proxy offset to src bounds and offset directly |
| return convolve_gaussian_2d(context, std::move(srcView), srcColorType, srcBounds, |
| dstBounds, radiusX, radiusY, sigmaX, sigmaY, mode, |
| std::move(colorSpace), fit); |
| } |
| // This will automatically degenerate into a single pass of X or Y if only one of the |
| // radii are non-zero. |
| return two_pass_gaussian(context, std::move(srcView), srcColorType, srcAlphaType, |
| std::move(colorSpace), srcBounds, dstBounds, sigmaX, sigmaY, |
| radiusX, radiusY, mode, fit); |
| } |
| |
| GrColorInfo colorInfo(srcColorType, srcAlphaType, colorSpace); |
| auto srcCtx = GrSurfaceContext::Make(context, srcView, colorInfo); |
| SkASSERT(srcCtx); |
| |
| float scaleX = sigmaX > kMaxSigma ? kMaxSigma/sigmaX : 1.f; |
| float scaleY = sigmaY > kMaxSigma ? kMaxSigma/sigmaY : 1.f; |
| // We round down here so that when we recalculate sigmas we know they will be below |
| // kMaxSigma (but clamp to 1 do we don't have an empty texture). |
| SkISize rescaledSize = {std::max(sk_float_floor2int(srcBounds.width() *scaleX), 1), |
| std::max(sk_float_floor2int(srcBounds.height()*scaleY), 1)}; |
| // Compute the sigmas using the actual scale factors used once we integerized the |
| // rescaledSize. |
| scaleX = static_cast<float>(rescaledSize.width()) /srcBounds.width(); |
| scaleY = static_cast<float>(rescaledSize.height())/srcBounds.height(); |
| sigmaX *= scaleX; |
| sigmaY *= scaleY; |
| |
| // When we are in clamp mode any artifacts in the edge pixels due to downscaling may be |
| // exacerbated because of the tile mode. The particularly egregious case is when the original |
| // image has transparent black around the edges and the downscaling pulls in some non-zero |
| // values from the interior. Ultimately it'd be better for performance if the calling code could |
| // give us extra context around the blur to account for this. We don't currently have a good way |
| // to communicate this up stack. So we leave a 1 pixel border around the rescaled src bounds. |
| // We populate the top 1 pixel tall row of this border by rescaling the top row of the original |
| // source bounds into it. Because this is only rescaling in x (i.e. rescaling a 1 pixel high |
| // row into a shorter but still 1 pixel high row) we won't read any interior values. And similar |
| // for the other three borders. We'll adjust the source/dest bounds rescaled blur so that this |
| // border of extra pixels is used as the edge pixels for clamp mode but the dest bounds |
| // corresponds only to the pixels inside the border (the normally rescaled pixels inside this |
| // border). |
| // Moreover, if we clamped the rescaled size to 1 column or row then we still have a sigma |
| // that is greater than kMaxSigma. By using a pad and making the src 3 wide/tall instead of |
| // 1 we can recurse again and do another downscale. Since mirror and repeat modes are trivial |
| // for a single col/row we only add padding based on sigma exceeding kMaxSigma for decal. |
| int padX = mode == SkTileMode::kClamp || |
| (mode == SkTileMode::kDecal && sigmaX > kMaxSigma) ? 1 : 0; |
| int padY = mode == SkTileMode::kClamp || |
| (mode == SkTileMode::kDecal && sigmaY > kMaxSigma) ? 1 : 0; |
| // Create the sdc with default SkSurfaceProps. Gaussian blurs will soon use a |
| // GrSurfaceFillContext, at which point the SkSurfaceProps won't exist anymore. |
| auto rescaledSDC = GrSurfaceDrawContext::Make( |
| srcCtx->recordingContext(), |
| colorInfo.colorType(), |
| colorInfo.refColorSpace(), |
| SkBackingFit::kApprox, |
| {rescaledSize.width() + 2*padX, rescaledSize.height() + 2*padY}, |
| SkSurfaceProps(), |
| 1, |
| GrMipmapped::kNo, |
| srcCtx->asSurfaceProxy()->isProtected(), |
| srcCtx->origin()); |
| if (!rescaledSDC) { |
| return nullptr; |
| } |
| if ((padX || padY) && mode == SkTileMode::kDecal) { |
| rescaledSDC->clear(SkPMColor4f{0, 0, 0, 0}); |
| } |
| if (!srcCtx->rescaleInto(rescaledSDC.get(), |
| SkIRect::MakeSize(rescaledSize).makeOffset(padX, padY), |
| srcBounds, |
| SkSurface::RescaleGamma::kSrc, |
| SkSurface::RescaleMode::kRepeatedLinear)) { |
| return nullptr; |
| } |
| if (mode == SkTileMode::kClamp) { |
| SkASSERT(padX == 1 && padY == 1); |
| // Rather than run a potentially multi-pass rescaler on single rows/columns we just do a |
| // single bilerp draw. If we find this quality unacceptable we should think more about how |
| // to rescale these with better quality but without 4 separate multi-pass downscales. |
| auto cheapDownscale = [&](SkIRect dstRect, SkIRect srcRect) { |
| rescaledSDC->drawTexture(nullptr, |
| srcCtx->readSurfaceView(), |
| srcAlphaType, |
| GrSamplerState::Filter::kLinear, |
| GrSamplerState::MipmapMode::kNone, |
| SkBlendMode::kSrc, |
| SK_PMColor4fWHITE, |
| SkRect::Make(srcRect), |
| SkRect::Make(dstRect), |
| GrAA::kNo, |
| GrQuadAAFlags::kNone, |
| SkCanvas::SrcRectConstraint::kFast_SrcRectConstraint, |
| SkMatrix::I(), |
| nullptr); |
| }; |
| auto [dw, dh] = rescaledSize; |
| // The are the src rows and columns from the source that we will scale into the dst padding. |
| float sLCol = srcBounds.left(); |
| float sTRow = srcBounds.top(); |
| float sRCol = srcBounds.right() - 1; |
| float sBRow = srcBounds.bottom() - 1; |
| |
| int sx = srcBounds.left(); |
| int sy = srcBounds.top(); |
| int sw = srcBounds.width(); |
| int sh = srcBounds.height(); |
| |
| // Downscale the edges from the original source. These draws should batch together (and with |
| // the above interior rescaling when it is a single pass). |
| cheapDownscale(SkIRect::MakeXYWH( 0, 1, 1, dh), |
| SkIRect::MakeXYWH( sLCol, sy, 1, sh)); |
| cheapDownscale(SkIRect::MakeXYWH( 1, 0, dw, 1), |
| SkIRect::MakeXYWH( sx, sTRow, sw, 1)); |
| cheapDownscale(SkIRect::MakeXYWH(dw + 1, 1, 1, dh), |
| SkIRect::MakeXYWH( sRCol, sy, 1, sh)); |
| cheapDownscale(SkIRect::MakeXYWH( 1, dh + 1, dw, 1), |
| SkIRect::MakeXYWH( sx, sBRow, sw, 1)); |
| |
| // Copy the corners from the original source. These would batch with the edges except that |
| // at time of writing we recognize these can use kNearest and downgrade the filter. So they |
| // batch with each other but not the edge draws. |
| cheapDownscale(SkIRect::MakeXYWH( 0, 0, 1, 1), |
| SkIRect::MakeXYWH(sLCol, sTRow, 1, 1)); |
| cheapDownscale(SkIRect::MakeXYWH(dw + 1, 0, 1, 1), |
| SkIRect::MakeXYWH(sRCol, sTRow, 1, 1)); |
| cheapDownscale(SkIRect::MakeXYWH(dw + 1,dh + 1, 1, 1), |
| SkIRect::MakeXYWH(sRCol, sBRow, 1, 1)); |
| cheapDownscale(SkIRect::MakeXYWH( 0, dh + 1, 1, 1), |
| SkIRect::MakeXYWH(sLCol, sBRow, 1, 1)); |
| } |
| srcView = rescaledSDC->readSurfaceView(); |
| // Drop the contexts so we don't hold the proxies longer than necessary. |
| rescaledSDC.reset(); |
| srcCtx.reset(); |
| |
| // Compute the dst bounds in the scaled down space. First move the origin to be at the top |
| // left since we trimmed off everything above and to the left of the original src bounds during |
| // the rescale. |
| SkRect scaledDstBounds = SkRect::Make(dstBounds.makeOffset(-srcBounds.topLeft())); |
| scaledDstBounds.fLeft *= scaleX; |
| scaledDstBounds.fTop *= scaleY; |
| scaledDstBounds.fRight *= scaleX; |
| scaledDstBounds.fBottom *= scaleY; |
| // Account for padding in our rescaled src, if any. |
| scaledDstBounds.offset(padX, padY); |
| // Turn the scaled down dst bounds into an integer pixel rect. |
| auto scaledDstBoundsI = scaledDstBounds.roundOut(); |
| |
| SkIRect scaledSrcBounds = SkIRect::MakeSize(srcView.dimensions()); |
| auto sdc = GaussianBlur(context, |
| std::move(srcView), |
| srcColorType, |
| srcAlphaType, |
| colorSpace, |
| scaledDstBoundsI, |
| scaledSrcBounds, |
| sigmaX, |
| sigmaY, |
| mode, |
| fit); |
| if (!sdc) { |
| return nullptr; |
| } |
| // We rounded out the integer scaled dst bounds. Select the fractional dst bounds from the |
| // integer dimension blurred result when we scale back up. |
| scaledDstBounds.offset(-scaledDstBoundsI.left(), -scaledDstBoundsI.top()); |
| return reexpand(context, std::move(sdc), scaledDstBounds, dstBounds.size(), |
| std::move(colorSpace), fit); |
| } |
| #endif // SK_GPU_V1 |
| |
| bool ComputeBlurredRRectParams(const SkRRect& srcRRect, const SkRRect& devRRect, |
| SkScalar sigma, SkScalar xformedSigma, |
| SkRRect* rrectToDraw, |
| SkISize* widthHeight, |
| SkScalar rectXs[kBlurRRectMaxDivisions], |
| SkScalar rectYs[kBlurRRectMaxDivisions], |
| SkScalar texXs[kBlurRRectMaxDivisions], |
| SkScalar texYs[kBlurRRectMaxDivisions]) { |
| unsigned int devBlurRadius = 3*SkScalarCeilToInt(xformedSigma-1/6.0f); |
| SkScalar srcBlurRadius = 3.0f * sigma; |
| |
| const SkRect& devOrig = devRRect.getBounds(); |
| const SkVector& devRadiiUL = devRRect.radii(SkRRect::kUpperLeft_Corner); |
| const SkVector& devRadiiUR = devRRect.radii(SkRRect::kUpperRight_Corner); |
| const SkVector& devRadiiLR = devRRect.radii(SkRRect::kLowerRight_Corner); |
| const SkVector& devRadiiLL = devRRect.radii(SkRRect::kLowerLeft_Corner); |
| |
| const int devLeft = SkScalarCeilToInt(std::max<SkScalar>(devRadiiUL.fX, devRadiiLL.fX)); |
| const int devTop = SkScalarCeilToInt(std::max<SkScalar>(devRadiiUL.fY, devRadiiUR.fY)); |
| const int devRight = SkScalarCeilToInt(std::max<SkScalar>(devRadiiUR.fX, devRadiiLR.fX)); |
| const int devBot = SkScalarCeilToInt(std::max<SkScalar>(devRadiiLL.fY, devRadiiLR.fY)); |
| |
| // This is a conservative check for nine-patchability |
| if (devOrig.fLeft + devLeft + devBlurRadius >= devOrig.fRight - devRight - devBlurRadius || |
| devOrig.fTop + devTop + devBlurRadius >= devOrig.fBottom - devBot - devBlurRadius) { |
| return false; |
| } |
| |
| const SkVector& srcRadiiUL = srcRRect.radii(SkRRect::kUpperLeft_Corner); |
| const SkVector& srcRadiiUR = srcRRect.radii(SkRRect::kUpperRight_Corner); |
| const SkVector& srcRadiiLR = srcRRect.radii(SkRRect::kLowerRight_Corner); |
| const SkVector& srcRadiiLL = srcRRect.radii(SkRRect::kLowerLeft_Corner); |
| |
| const SkScalar srcLeft = std::max<SkScalar>(srcRadiiUL.fX, srcRadiiLL.fX); |
| const SkScalar srcTop = std::max<SkScalar>(srcRadiiUL.fY, srcRadiiUR.fY); |
| const SkScalar srcRight = std::max<SkScalar>(srcRadiiUR.fX, srcRadiiLR.fX); |
| const SkScalar srcBot = std::max<SkScalar>(srcRadiiLL.fY, srcRadiiLR.fY); |
| |
| int newRRWidth = 2*devBlurRadius + devLeft + devRight + 1; |
| int newRRHeight = 2*devBlurRadius + devTop + devBot + 1; |
| widthHeight->fWidth = newRRWidth + 2 * devBlurRadius; |
| widthHeight->fHeight = newRRHeight + 2 * devBlurRadius; |
| |
| const SkRect srcProxyRect = srcRRect.getBounds().makeOutset(srcBlurRadius, srcBlurRadius); |
| |
| rectXs[0] = srcProxyRect.fLeft; |
| rectXs[1] = srcProxyRect.fLeft + 2*srcBlurRadius + srcLeft; |
| rectXs[2] = srcProxyRect.fRight - 2*srcBlurRadius - srcRight; |
| rectXs[3] = srcProxyRect.fRight; |
| |
| rectYs[0] = srcProxyRect.fTop; |
| rectYs[1] = srcProxyRect.fTop + 2*srcBlurRadius + srcTop; |
| rectYs[2] = srcProxyRect.fBottom - 2*srcBlurRadius - srcBot; |
| rectYs[3] = srcProxyRect.fBottom; |
| |
| texXs[0] = 0.0f; |
| texXs[1] = 2.0f*devBlurRadius + devLeft; |
| texXs[2] = 2.0f*devBlurRadius + devLeft + 1; |
| texXs[3] = SkIntToScalar(widthHeight->fWidth); |
| |
| texYs[0] = 0.0f; |
| texYs[1] = 2.0f*devBlurRadius + devTop; |
| texYs[2] = 2.0f*devBlurRadius + devTop + 1; |
| texYs[3] = SkIntToScalar(widthHeight->fHeight); |
| |
| const SkRect newRect = SkRect::MakeXYWH(SkIntToScalar(devBlurRadius), |
| SkIntToScalar(devBlurRadius), |
| SkIntToScalar(newRRWidth), |
| SkIntToScalar(newRRHeight)); |
| SkVector newRadii[4]; |
| newRadii[0] = { SkScalarCeilToScalar(devRadiiUL.fX), SkScalarCeilToScalar(devRadiiUL.fY) }; |
| newRadii[1] = { SkScalarCeilToScalar(devRadiiUR.fX), SkScalarCeilToScalar(devRadiiUR.fY) }; |
| newRadii[2] = { SkScalarCeilToScalar(devRadiiLR.fX), SkScalarCeilToScalar(devRadiiLR.fY) }; |
| newRadii[3] = { SkScalarCeilToScalar(devRadiiLL.fX), SkScalarCeilToScalar(devRadiiLL.fY) }; |
| |
| rrectToDraw->setRectRadii(newRect, newRadii); |
| return true; |
| } |
| |
| // TODO: it seems like there should be some synergy with SkBlurMask::ComputeBlurProfile |
| // TODO: maybe cache this on the cpu side? |
| int CreateIntegralTable(float sixSigma, SkBitmap* table) { |
| // The texture we're producing represents the integral of a normal distribution over a |
| // six-sigma range centered at zero. We want enough resolution so that the linear |
| // interpolation done in texture lookup doesn't introduce noticeable artifacts. We |
| // conservatively choose to have 2 texels for each dst pixel. |
| int minWidth = 2 * sk_float_ceil2int(sixSigma); |
| // Bin by powers of 2 with a minimum so we get good profile reuse. |
| int width = std::max(SkNextPow2(minWidth), 32); |
| |
| if (!table) { |
| return width; |
| } |
| |
| if (!table->tryAllocPixels(SkImageInfo::MakeA8(width, 1))) { |
| return 0; |
| } |
| *table->getAddr8(0, 0) = 255; |
| const float invWidth = 1.f / width; |
| for (int i = 1; i < width - 1; ++i) { |
| float x = (i + 0.5f) * invWidth; |
| x = (-6 * x + 3) * SK_ScalarRoot2Over2; |
| float integral = 0.5f * (std::erf(x) + 1.f); |
| *table->getAddr8(i, 0) = SkToU8(sk_float_round2int(255.f * integral)); |
| } |
| |
| *table->getAddr8(width - 1, 0) = 0; |
| table->setImmutable(); |
| return table->width(); |
| } |
| |
| |
| void Compute1DGaussianKernel(float* kernel, float sigma, int radius) { |
| SkASSERT(radius == SigmaRadius(sigma)); |
| if (SkGpuBlurUtils::IsEffectivelyZeroSigma(sigma)) { |
| // Calling SigmaRadius() produces 1, just computing ceil(sigma)*3 produces 3 |
| SkASSERT(KernelWidth(radius) == 1); |
| std::fill_n(kernel, 1, 0.f); |
| kernel[0] = 1.f; |
| return; |
| } |
| |
| // If this fails, kEffectivelyZeroSigma isn't big enough to prevent precision issues |
| SkASSERT(!SkScalarNearlyZero(2.f * sigma * sigma)); |
| |
| const float sigmaDenom = 1.0f / (2.f * sigma * sigma); |
| int size = KernelWidth(radius); |
| float sum = 0.0f; |
| for (int i = 0; i < size; ++i) { |
| float term = static_cast<float>(i - radius); |
| // Note that the constant term (1/(sqrt(2*pi*sigma^2)) of the Gaussian |
| // is dropped here, since we renormalize the kernel below. |
| kernel[i] = sk_float_exp(-term * term * sigmaDenom); |
| sum += kernel[i]; |
| } |
| // Normalize the kernel |
| float scale = 1.0f / sum; |
| for (int i = 0; i < size; ++i) { |
| kernel[i] *= scale; |
| } |
| } |
| |
| void Compute1DLinearGaussianKernel(float* kernel, float* offset, float sigma, int radius) { |
| // Given 2 adjacent gaussian points, they are blended as: Wi * Ci + Wj * Cj. |
| // The GPU will mix Ci and Cj as Ci * (1 - x) + Cj * x during sampling. |
| // Compute W', x such that W' * (Ci * (1 - x) + Cj * x) = Wi * Ci + Wj * Cj. |
| // Solving W' * x = Wj, W' * (1 - x) = Wi: |
| // W' = Wi + Wj |
| // x = Wj / (Wi + Wj) |
| auto get_new_weight = [](float* new_w, float* offset, float wi, float wj) { |
| *new_w = wi + wj; |
| *offset = wj / (wi + wj); |
| }; |
| |
| // Create a temporary standard kernel. |
| int size = KernelWidth(radius); |
| std::unique_ptr<float[]> temp_kernel(new float[size]); |
| Compute1DGaussianKernel(temp_kernel.get(), sigma, radius); |
| |
| // Note that halfsize isn't just size / 2, but radius + 1. This is the size of the output array. |
| int halfsize = LinearKernelWidth(radius); |
| int halfradius = halfsize / 2; |
| int low_index = halfradius - 1; |
| |
| // Compute1DGaussianKernel produces a full 2N + 1 kernel. Since the kernel can be mirrored, |
| // compute only the upper half and mirror to the lower half. |
| |
| int index = radius; |
| if (radius & 1) { |
| // If N is odd, then use two samples. |
| // The centre texel gets sampled twice, so halve its influence for each sample. |
| // We essentially sample like this: |
| // Texel edges |
| // v v v v |
| // | | | | |
| // \-----^---/ Lower sample |
| // \---^-----/ Upper sample |
| get_new_weight(&kernel[halfradius], &offset[halfradius], |
| temp_kernel[index] * 0.5f, temp_kernel[index + 1]); |
| kernel[low_index] = kernel[halfradius]; |
| offset[low_index] = -offset[halfradius]; |
| index++; |
| low_index--; |
| } else { |
| // If N is even, then there are an even number of texels on either side of the centre texel. |
| // Sample the centre texel directly. |
| kernel[halfradius] = temp_kernel[index]; |
| offset[halfradius] = 0.0f; |
| } |
| index++; |
| |
| // Every other pair gets one sample. |
| for (int i = halfradius + 1; i < halfsize; index += 2, i++, low_index--) { |
| get_new_weight(&kernel[i], &offset[i], temp_kernel[index], temp_kernel[index + 1]); |
| offset[i] += static_cast<float>(index - radius); |
| |
| // Mirror to lower half. |
| kernel[low_index] = kernel[i]; |
| offset[low_index] = -offset[i]; |
| } |
| } |
| |
| } // namespace SkGpuBlurUtils |
| |
| #endif |
