Generate Signed Distance Field directly from vector path

src/gpu/GrDistanceFieldGenFromVector.h

+/*
+ * Copyright 2017 ARM Ltd.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrDistanceFieldGenFromVector_DEFINED
+#define GrDistanceFieldGenFromVector_DEFINED
+
+#include "SkPath.h"
+
+class SkMatrix;
+
+#ifndef SK_USE_LEGACY_DISTANCE_FIELDS
+    #define SK_USE_LEGACY_DISTANCE_FIELDS
+#endif
+
+/** Given a vector path, generate the associated distance field.
+
+ *  @param distanceField     The distance field to be generated. Should already be allocated
+ *                           by the client with the padding defined in "SkDistanceFieldGen.h".
+ *  @param path              The path we're using to generate the distance field.
+ *  @param matrix            Transformation matrix for path.
+ *  @param width             Width of the distance field.
+ *  @param height            Height of the distance field.
+ *  @param rowBytes          Size of each row in the distance field, in bytes.
+ */
+bool GrGenerateDistanceFieldFromPath(unsigned char* distanceField,
+                                     const SkPath& path, const SkMatrix& viewMatrix,
+                                     int width, int height, size_t rowBytes);
+
+inline bool IsDistanceFieldSupportedFillType(SkPath::FillType fFillType)
+{
+        return (SkPath::kEvenOdd_FillType == fFillType ||
+            SkPath::kInverseEvenOdd_FillType == fFillType);
+}
+
+#endif