converted GrRectBlurEffect to SkSL

Bug: skia:
Change-Id: I3a8e16fd2792e6fb5711815d8aad46ae30c2872e
Reviewed-on: https://skia-review.googlesource.com/59163
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

1 files changed, 100 insertions, 0 deletions

diff --git a/src/gpu/effects/GrRectBlurEffect.h b/src/gpu/effects/GrRectBlurEffect.h
new file mode 100644
index 0000000000..7a8bc2c005
--- /dev/null
+++ b/src/gpu/effects/GrRectBlurEffect.h
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/*
+ * This file was autogenerated from GrRectBlurEffect.fp; do not modify.
+ */
+#ifndef GrRectBlurEffect_DEFINED
+#define GrRectBlurEffect_DEFINED
+#include "SkTypes.h"
+#if SK_SUPPORT_GPU
+
+#include "GrResourceProvider.h"
+#include "../effects/SkBlurMask.h"
+#include "GrFragmentProcessor.h"
+#include "GrCoordTransform.h"
+#include "GrColorSpaceXform.h"
+class GrRectBlurEffect : public GrFragmentProcessor {
+public:
+    static sk_sp<GrTextureProxy> CreateBlurProfileTexture(GrResourceProvider* resourceProvider,
+                                                          float sigma) {
+        unsigned int profileSize = SkScalarCeilToInt(6 * sigma);
+
+        static const GrUniqueKey::Domain kDomain = GrUniqueKey::GenerateDomain();
+        GrUniqueKey key;
+        GrUniqueKey::Builder builder(&key, kDomain, 1);
+        builder[0] = profileSize;
+        builder.finish();
+
+        sk_sp<GrTextureProxy> blurProfile(
+                resourceProvider->findOrCreateProxyByUniqueKey(key, kTopLeft_GrSurfaceOrigin));
+        if (!blurProfile) {
+            GrSurfaceDesc texDesc;
+            texDesc.fOrigin = kTopLeft_GrSurfaceOrigin;
+            texDesc.fWidth = profileSize;
+            texDesc.fHeight = 1;
+            texDesc.fConfig = kAlpha_8_GrPixelConfig;
+
+            std::unique_ptr<uint8_t[]> profile(SkBlurMask::ComputeBlurProfile(sigma));
+
+            blurProfile = GrSurfaceProxy::MakeDeferred(resourceProvider, texDesc, SkBudgeted::kYes,
+                                                       profile.get(), 0);
+            if (!blurProfile) {
+                return nullptr;
+            }
+
+            SkASSERT(blurProfile->origin() == kTopLeft_GrSurfaceOrigin);
+            resourceProvider->assignUniqueKeyToProxy(key, blurProfile.get());
+        }
+
+        return blurProfile;
+    }
+    SkRect rect() const { return fRect; }
+    float sigma() const { return fSigma; }
+
+    static std::unique_ptr<GrFragmentProcessor> Make(GrResourceProvider* resourceProvider,
+                                                     const SkRect& rect, float sigma) {
+        int doubleProfileSize = SkScalarCeilToInt(12 * sigma);
+
+        if (doubleProfileSize >= rect.width() || doubleProfileSize >= rect.height()) {
+            // if the blur sigma is too large so the gaussian overlaps the whole
+            // rect in either direction, fall back to CPU path for now.
+            return nullptr;
+        }
+
+        sk_sp<GrTextureProxy> blurProfile(CreateBlurProfileTexture(resourceProvider, sigma));
+        if (!blurProfile) {
+            return nullptr;
+        }
+
+        return std::unique_ptr<GrFragmentProcessor>(
+                new GrRectBlurEffect(rect, sigma, std::move(blurProfile)));
+    }
+    GrRectBlurEffect(const GrRectBlurEffect& src);
+    std::unique_ptr<GrFragmentProcessor> clone() const override;
+    const char* name() const override { return "RectBlurEffect"; }
+
+private:
+    GrRectBlurEffect(SkRect rect, float sigma, sk_sp<GrTextureProxy> blurProfile)
+            : INHERITED(kGrRectBlurEffect_ClassID,
+                        (OptimizationFlags)kCompatibleWithCoverageAsAlpha_OptimizationFlag)
+            , fRect(rect)
+            , fSigma(sigma)
+            , fBlurProfile(std::move(blurProfile)) {
+        this->addTextureSampler(&fBlurProfile);
+    }
+    GrGLSLFragmentProcessor* onCreateGLSLInstance() const override;
+    void onGetGLSLProcessorKey(const GrShaderCaps&, GrProcessorKeyBuilder*) const override;
+    bool onIsEqual(const GrFragmentProcessor&) const override;
+    GR_DECLARE_FRAGMENT_PROCESSOR_TEST
+    SkRect fRect;
+    float fSigma;
+    TextureSampler fBlurProfile;
+    typedef GrFragmentProcessor INHERITED;
+};
+#endif
+#endif