Convert from rand() to C++11 random

microsoft · May 30, 2021 · 4ca2c5c · 4ca2c5c
1 parent 67dd58e
commit 4ca2c5c
Show file tree

Hide file tree

Showing 6 changed files with 20 additions and 2 deletions.
diff --git a/UVAtlas/isochart/UVAtlasRepacker.cpp b/UVAtlas/isochart/UVAtlasRepacker.cpp
@@ -125,6 +125,8 @@ CUVAtlasRepacker::CUVAtlasRepacker(std::vector<UVAtlasVertex>* pvVertexArray,
     m_pOurChartNumber(pChartNumber),
     m_pOurIterationTimes(pIterationTimes)
 {
+    std::random_device randomDevice;
+    m_randomEngine.seed(randomDevice());
 }
 
 /***************************************************************************\
@@ -1301,6 +1303,8 @@ void CUVAtlasRepacker::PutChart(uint32_t index)
 
     m_triedInternalSpace = int(1e8f);
 
+    std::uniform_int_distribution<> dis(0, 1);
+
     for (uint32_t i = 0; i < m_iRotateNum; i++)
     {
         // for every position of chart, first do tessellation on it
@@ -1318,7 +1322,7 @@ void CUVAtlasRepacker::PutChart(uint32_t index)
         else if (m_currAspectRatio < m_AspectRatio)
             PutSide = 1;
         else
-            PutSide = int(floorf(float(rand()) + 0.5f));
+            PutSide = dis(m_randomEngine);
 
         if (PutSide == 0) // put on left or right side
         {

diff --git a/UVAtlas/isochart/UVAtlasRepacker.h b/UVAtlas/isochart/UVAtlasRepacker.h
@@ -311,6 +311,8 @@ namespace IsochartRepacker
         size_t* m_pOurIterationTimes;
 
         Isochart::CCallbackSchemer m_callbackSchemer;
+
+        std::mt19937_64 m_randomEngine;
     };
 
 }
diff --git a/UVAtlas/isochart/isochartengine.cpp b/UVAtlas/isochart/isochartengine.cpp
@@ -42,6 +42,8 @@ CIsochartEngine::CIsochartEngine() :
 #endif
     m_dwOptions(_OPTION_ISOCHART_DEFAULT)
 {
+    std::random_device randomDevice;
+    m_randomEngine.seed(randomDevice());
 }
 
 CIsochartEngine::~CIsochartEngine()

diff --git a/UVAtlas/isochart/isochartengine.h b/UVAtlas/isochart/isochartengine.h
@@ -80,6 +80,13 @@ namespace Isochart
             const uint32_t* pdwFaceAdjacentArrayIn) noexcept override;
 
         HRESULT CreateEngineMutex();
+
+        float UniformRand(float maxValue) const
+        {
+            std::uniform_real_distribution<float> dis(0.f, maxValue);
+            return dis(m_randomEngine);
+        }
+
     private:
         enum EngineState
         {
@@ -248,6 +255,8 @@ namespace Isochart
 
         unsigned int m_dwOptions;
 
+        mutable std::mt19937_64 m_randomEngine;
+
         friend CIsochartMesh;
     };
 

diff --git a/UVAtlas/isochart/meshoptimizestretch.cpp b/UVAtlas/isochart/meshoptimizestretch.cpp
@@ -1820,7 +1820,7 @@ bool CIsochartMesh::OptimizeVertexStretchAroundCenter(
     while (iteration < optimizeInfo.dwRandOptOneVertTimes)
     {
         // 1. Get a new random position in the optimizing circle range
-        float fAngle = float(rand()) * 2.f * XM_PI / RAND_MAX;
+        float fAngle = m_IsochartEngine.UniformRand(2.f * XM_PI);
         vertInfo.end.x =
             vertInfo.center.x + vertInfo.fRadius * cosf(fAngle);
         vertInfo.end.y =

diff --git a/UVAtlas/pch.h b/UVAtlas/pch.h
@@ -91,6 +91,7 @@
 #include <functional>
 #include <memory>
 #include <new>
+#include <random>
 #include <utility>
 #include <vector>
 #include <queue>