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diff --git a/include/core/SkRandom.h b/include/core/SkRandom.h
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+++ b/include/core/SkRandom.h
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+/*
+ * Copyright (C) 2006 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef SkRandom_DEFINED
+#define SkRandom_DEFINED
+
+#include "Sk64.h"
+#include "SkScalar.h"
+
+/** \class SkRandom
+
+    Utility class that implements pseudo random 32bit numbers using a fast
+    linear equation. Unlike rand(), this class holds its own seed (initially
+    set to 0), so that multiple instances can be used with no side-effects.
+*/
+class SkRandom {
+public:
+    SkRandom() : fSeed(0) {}
+    SkRandom(uint32_t seed) : fSeed(seed) {}
+
+    /** Return the next pseudo random number as an unsigned 32bit value.
+    */
+    uint32_t nextU() { uint32_t r = fSeed * kMul + kAdd; fSeed = r; return r; }
+
+    /** Return the next pseudo random number as a signed 32bit value.
+    */
+    int32_t nextS() { return (int32_t)this->nextU(); }
+
+    /** Return the next pseudo random number as an unsigned 16bit value.
+    */
+    U16CPU nextU16() { return this->nextU() >> 16; }
+
+    /** Return the next pseudo random number as a signed 16bit value.
+    */
+    S16CPU nextS16() { return this->nextS() >> 16; }
+
+    /** Return the next pseudo random number, as an unsigned value of
+        at most bitCount bits.
+        @param bitCount The maximum number of bits to be returned
+    */
+    uint32_t nextBits(unsigned bitCount) {
+        SkASSERT(bitCount > 0 && bitCount <= 32);
+        return this->nextU() >> (32 - bitCount);
+    }
+
+    /** Return the next pseudo random unsigned number, mapped to lie within
+        [min, max] inclusive.
+    */
+    uint32_t nextRangeU(uint32_t min, uint32_t max) {
+        SkASSERT(min <= max);
+        return min + this->nextU() % (max - min + 1);
+    }
+
+    /** Return the next pseudo random number expressed as an unsigned SkFixed
+        in the range [0..SK_Fixed1).
+    */
+    SkFixed nextUFixed1() { return this->nextU() >> 16; }
+
+    /** Return the next pseudo random number expressed as a signed SkFixed
+        in the range (-SK_Fixed1..SK_Fixed1).
+    */
+    SkFixed nextSFixed1() { return this->nextS() >> 15; }
+
+    /** Return the next pseudo random number expressed as a SkScalar
+        in the range [0..SK_Scalar1).
+    */
+    SkScalar nextUScalar1() { return SkFixedToScalar(this->nextUFixed1()); }
+
+    /** Return the next pseudo random number expressed as a SkScalar
+        in the range (-SK_Scalar1..SK_Scalar1).
+    */
+    SkScalar nextSScalar1() { return SkFixedToScalar(this->nextSFixed1()); }
+
+    /** Return the next pseudo random number as a signed 64bit value.
+    */
+    void next64(Sk64* a) {
+        SkASSERT(a);
+        a->set(this->nextS(), this->nextU());
+    }
+
+    /** Set the seed of the random object. The seed is initialized to 0 when the
+        object is first created, and is updated each time the next pseudo random
+        number is requested.
+    */
+    void setSeed(int32_t seed) { fSeed = (uint32_t)seed; }
+
+private:
+    //  See "Numerical Recipes in C", 1992 page 284 for these constants
+    enum {
+        kMul = 1664525,
+        kAdd = 1013904223
+    };
+    uint32_t fSeed;
+};
+
+#endif
+