blob: 62da59139f969a67fa5d25db9b666de180c20188 [file] [log] [blame]
* Copyright 2013 Google Inc.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
#ifndef SkGpuBlurUtils_DEFINED
#define SkGpuBlurUtils_DEFINED
#include "src/gpu/GrRenderTargetContext.h"
#include "src/gpu/effects/GrTextureDomain.h"
class GrContext;
class GrTexture;
struct SkRect;
namespace SkGpuBlurUtils {
* Applies a 2D Gaussian blur to a given texture. The blurred result is returned
* as a renderTargetContext in case the caller wishes to future draw into the result.
* The 'proxyOffset' is kept separate form 'srcBounds' because they exist in different
* coordinate spaces. 'srcBounds' exists in the content space of the special image, and
* 'proxyOffset' maps from the content space to the proxy's space.
* Note: one of sigmaX and sigmaY should be non-zero!
* @param context The GPU context
* @param src The source to be blurred.
* @param proxyOffset The offset from the top-left corner to valid texels in 'src', which
* should come from the subset of the owning SkSpecialImage.
* @param colorSpace Color space of the source (used for the renderTargetContext result,
* too).
* @param dstBounds The destination bounds, relative to the source texture.
* @param srcBounds The source bounds, relative to the source texture's offset. No pixels
* will be sampled outside of this rectangle.
* @param sigmaX The blur's standard deviation in X.
* @param sigmaY The blur's standard deviation in Y.
* @param mode The mode to handle samples outside bounds.
* @param fit backing fit for the returned render target context
* @return The renderTargetContext containing the blurred result.
sk_sp<GrRenderTargetContext> GaussianBlur(
GrRecordingContext* context,
sk_sp<GrTextureProxy> src,
const SkIPoint& proxyOffset,
sk_sp<SkColorSpace> colorSpace,
const SkIRect& dstBounds,
const SkIRect& srcBounds,
float sigmaX,
float sigmaY,
GrTextureDomain::Mode mode,
SkAlphaType at,
SkBackingFit fit = SkBackingFit::kApprox);