converted CircleEffect to SkSL

Bug: skia:
Change-Id: I93d117c22ae2b374294f6a5e961c497ac2c92b09
Reviewed-on: https://skia-review.googlesource.com/23301
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
diff --git a/src/gpu/effects/GrCircleEffect.cpp b/src/gpu/effects/GrCircleEffect.cpp
new file mode 100644
index 0000000..acd2a9b
--- /dev/null
+++ b/src/gpu/effects/GrCircleEffect.cpp
@@ -0,0 +1,88 @@
+/*
+ * 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 GrCircleEffect.fp; do not modify.
+ */
+#include "GrCircleEffect.h"
+#if SK_SUPPORT_GPU
+#include "glsl/GrGLSLColorSpaceXformHelper.h"
+#include "glsl/GrGLSLFragmentProcessor.h"
+#include "glsl/GrGLSLFragmentShaderBuilder.h"
+#include "glsl/GrGLSLProgramBuilder.h"
+#include "SkSLCPP.h"
+#include "SkSLUtil.h"
+class GrGLSLCircleEffect : public GrGLSLFragmentProcessor {
+public:
+    GrGLSLCircleEffect() {}
+    void emitCode(EmitArgs& args) override {
+        GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
+        const GrCircleEffect& _outer = args.fFp.cast<GrCircleEffect>();
+        (void) _outer;
+prevRadius = -1.0;
+        fCircleVar = args.fUniformHandler->addUniform(kFragment_GrShaderFlag, kVec4f_GrSLType, kDefault_GrSLPrecision, "circle");
+        fragBuilder->codeAppendf("vec2 prevCenter;\nfloat prevRadius = %f;\nfloat d;\nif (%d == 2 || %d == 3) {\n    d = (length((%s.xy - sk_FragCoord.xy) * %s.w) - 1.0) * %s.z;\n} else {\n    d = (1.0 - length((%s.xy - sk_FragCoord.xy) * %s.w)) * %s.z;\n}\nif ((%d == 1 || %d == 3) || %d == 4) {\n    d = clamp(d, 0.0, 1.0);\n} else {\n    d = d > 0.5 ? 1.0 : 0.0;\n}\n%s = %s * d;\n", prevRadius, _outer.edgeType(), _outer.edgeType(), args.fUniformHandler->getUniformCStr(fCircleVar), args.fUniformHandler->getUniformCStr(fCircleVar), args.fUniformHandler->getUniformCStr(fCircleVar), args.fUniformHandler->getUniformCStr(fCircleVar), args.fUniformHandler->getUniformCStr(fCircleVar), args.fUniformHandler->getUniformCStr(fCircleVar), _outer.edgeType(), _outer.edgeType(), _outer.edgeType(), args.fOutputColor, args.fInputColor ? args.fInputColor : "vec4(1)");
+    }
+private:
+    void onSetData(const GrGLSLProgramDataManager& pdman, const GrFragmentProcessor& _proc) override {
+        const GrCircleEffect& _outer = _proc.cast<GrCircleEffect>();
+        auto edgeType = _outer.edgeType();
+        (void) edgeType;
+        auto center = _outer.center();
+        (void) center;
+        auto radius = _outer.radius();
+        (void) radius;
+        UniformHandle& circle = fCircleVar;
+        (void) circle;
+
+    if (radius != prevRadius || center != prevCenter) {
+        SkScalar effectiveRadius = radius;
+        if (GrProcessorEdgeTypeIsInverseFill((GrPrimitiveEdgeType) edgeType)) {
+            effectiveRadius -= 0.5f;
+        } else {
+            effectiveRadius += 0.5f;
+        }
+        pdman.set4f(circle, center.fX, center.fY, effectiveRadius,
+                    SkScalarInvert(effectiveRadius));
+        prevCenter = center;
+        prevRadius = radius;
+    }
+    }
+SkPoint prevCenter;
+float prevRadius;
+    UniformHandle fCircleVar;
+};
+GrGLSLFragmentProcessor* GrCircleEffect::onCreateGLSLInstance() const {
+    return new GrGLSLCircleEffect();
+}
+void GrCircleEffect::onGetGLSLProcessorKey(const GrShaderCaps& caps, GrProcessorKeyBuilder* b) const {
+    b->add32(fEdgeType);
+}
+bool GrCircleEffect::onIsEqual(const GrFragmentProcessor& other) const {
+    const GrCircleEffect& that = other.cast<GrCircleEffect>();
+    (void) that;
+    if (fEdgeType != that.fEdgeType) return false;
+    if (fCenter != that.fCenter) return false;
+    if (fRadius != that.fRadius) return false;
+    return true;
+}
+GR_DEFINE_FRAGMENT_PROCESSOR_TEST(GrCircleEffect);
+#if GR_TEST_UTILS
+sk_sp<GrFragmentProcessor> GrCircleEffect::TestCreate(GrProcessorTestData* testData) {
+
+    SkPoint center;
+    center.fX = testData->fRandom->nextRangeScalar(0.f, 1000.f);
+    center.fY = testData->fRandom->nextRangeScalar(0.f, 1000.f);
+    SkScalar radius = testData->fRandom->nextRangeF(0.f, 1000.f);
+    GrPrimitiveEdgeType et;
+    do {
+        et = (GrPrimitiveEdgeType) testData->fRandom->nextULessThan(kGrProcessorEdgeTypeCnt);
+    } while (kHairlineAA_GrProcessorEdgeType == et);
+    return GrCircleEffect::Make(et, center, radius);
+}
+#endif
+#endif