ec3ed6a5eb
I have manually examined all of these diffs and restored a few files that seem to require manual adjustment. The following files still need to be modified manually, in a separate CL: android_sample/SampleApp/AndroidManifest.xml android_sample/SampleApp/res/layout/layout.xml android_sample/SampleApp/res/menu/sample.xml android_sample/SampleApp/res/values/strings.xml android_sample/SampleApp/src/com/skia/sampleapp/SampleApp.java android_sample/SampleApp/src/com/skia/sampleapp/SampleView.java experimental/CiCarbonSampleMain.c experimental/CocoaDebugger/main.m experimental/FileReaderApp/main.m experimental/SimpleCocoaApp/main.m experimental/iOSSampleApp/Shared/SkAlertPrompt.h experimental/iOSSampleApp/Shared/SkAlertPrompt.m experimental/iOSSampleApp/SkiOSSampleApp-Base.xcconfig experimental/iOSSampleApp/SkiOSSampleApp-Debug.xcconfig experimental/iOSSampleApp/SkiOSSampleApp-Release.xcconfig gpu/src/android/GrGLDefaultInterface_android.cpp gyp/common.gypi gyp_skia include/ports/SkHarfBuzzFont.h include/views/SkOSWindow_wxwidgets.h make.bat make.py src/opts/memset.arm.S src/opts/memset16_neon.S src/opts/memset32_neon.S src/opts/opts_check_arm.cpp src/ports/SkDebug_brew.cpp src/ports/SkMemory_brew.cpp src/ports/SkOSFile_brew.cpp src/ports/SkXMLParser_empty.cpp src/utils/ios/SkImageDecoder_iOS.mm src/utils/ios/SkOSFile_iOS.mm src/utils/ios/SkStream_NSData.mm tests/FillPathTest.cpp Review URL: http://codereview.appspot.com/4816058 git-svn-id: http://skia.googlecode.com/svn/trunk@1982 2bbb7eff-a529-9590-31e7-b0007b416f81
104 lines
3.1 KiB
C++
104 lines
3.1 KiB
C++
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/*
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* Copyright 2006 The Android Open Source Project
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*
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* Use of this source code is governed by a BSD-style license that can be
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* found in the LICENSE file.
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*/
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#ifndef SkRandom_DEFINED
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#define SkRandom_DEFINED
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#include "Sk64.h"
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#include "SkScalar.h"
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/** \class SkRandom
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Utility class that implements pseudo random 32bit numbers using a fast
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linear equation. Unlike rand(), this class holds its own seed (initially
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set to 0), so that multiple instances can be used with no side-effects.
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*/
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class SkRandom {
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public:
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SkRandom() : fSeed(0) {}
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SkRandom(uint32_t seed) : fSeed(seed) {}
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/** Return the next pseudo random number as an unsigned 32bit value.
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*/
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uint32_t nextU() { uint32_t r = fSeed * kMul + kAdd; fSeed = r; return r; }
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/** Return the next pseudo random number as a signed 32bit value.
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*/
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int32_t nextS() { return (int32_t)this->nextU(); }
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/** Return the next pseudo random number as an unsigned 16bit value.
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*/
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U16CPU nextU16() { return this->nextU() >> 16; }
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/** Return the next pseudo random number as a signed 16bit value.
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*/
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S16CPU nextS16() { return this->nextS() >> 16; }
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/** Return the next pseudo random number, as an unsigned value of
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at most bitCount bits.
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@param bitCount The maximum number of bits to be returned
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*/
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uint32_t nextBits(unsigned bitCount) {
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SkASSERT(bitCount > 0 && bitCount <= 32);
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return this->nextU() >> (32 - bitCount);
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}
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/** Return the next pseudo random unsigned number, mapped to lie within
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[min, max] inclusive.
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*/
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uint32_t nextRangeU(uint32_t min, uint32_t max) {
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SkASSERT(min <= max);
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return min + this->nextU() % (max - min + 1);
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}
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/** Return the next pseudo random number expressed as an unsigned SkFixed
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in the range [0..SK_Fixed1).
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*/
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SkFixed nextUFixed1() { return this->nextU() >> 16; }
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/** Return the next pseudo random number expressed as a signed SkFixed
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in the range (-SK_Fixed1..SK_Fixed1).
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*/
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SkFixed nextSFixed1() { return this->nextS() >> 15; }
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/** Return the next pseudo random number expressed as a SkScalar
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in the range [0..SK_Scalar1).
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*/
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SkScalar nextUScalar1() { return SkFixedToScalar(this->nextUFixed1()); }
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/** Return the next pseudo random number expressed as a SkScalar
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in the range (-SK_Scalar1..SK_Scalar1).
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*/
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SkScalar nextSScalar1() { return SkFixedToScalar(this->nextSFixed1()); }
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/** Return the next pseudo random number as a signed 64bit value.
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*/
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void next64(Sk64* a) {
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SkASSERT(a);
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a->set(this->nextS(), this->nextU());
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}
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/** Set the seed of the random object. The seed is initialized to 0 when the
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object is first created, and is updated each time the next pseudo random
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number is requested.
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*/
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void setSeed(int32_t seed) { fSeed = (uint32_t)seed; }
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private:
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// See "Numerical Recipes in C", 1992 page 284 for these constants
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enum {
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kMul = 1664525,
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kAdd = 1013904223
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};
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uint32_t fSeed;
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};
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#endif
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