随笔-341  评论-2670  文章-0  trackbacks-0
    明天得开始研究别人是怎么处理材质的了。目前使用的方法是(反射来源×反射基准)×折射比率+(光源×材质颜色)×(1-折射比率)+[(折射来源+底面反射)×衰减+(1-衰减)]×透明物体内部颜色


    等材质完全做完之后,目前的渲染算法就可以为GI服务了。

    最后是计算混合的代码:
  1 VBool VL_RayRenderer::GetSample(IVL_RayGeometry::UnmanagedList& Objects , VRayPoint Position , VRayVector Direction , IVL_RayGeometry*& Geometry , VL_RayObjectSample& Sample)
  2 {
  3     VBool Available=false;
  4     for(VInt i=0;i<Objects.GetCount();i++)
  5     {
  6         VL_RayObjectSample TempSample;
  7         if(Objects[i]->GetNearestSample(Position,Direction,true,TempSample))
  8         {
  9             if(!Available)
 10             {
 11                 Geometry=Objects[i];
 12                 Sample=TempSample;
 13                 Available=true;
 14             }
 15             else if(TempSample.DirectionScale<=Sample.DirectionScale)
 16             {
 17                 Geometry=Objects[i];
 18                 Sample=TempSample;
 19             }
 20         }
 21     }
 22     return Available;
 23 }
 24 
 25 VRayColor VL_RayRenderer::GetRefractionColor(IVL_RayGeometry::UnmanagedList& Objects , IVL_RayGeometry* Object , VRayPoint Position , VRayVector Direction , VInt ReflectionCounter)
 26 {
 27     VL_RayObjectSample Sample;
 28     if(Object->GetNearestSample(Position,Direction,false,Sample))
 29     {
 30         VDouble RefractionLength=(Sample.Position-Position).Length();
 31         VDouble InternalRatio=1-pow(Sample.RefractionIndex,-RefractionLength);
 32         VDouble OutRatio=0;
 33         VRayColor OutColor(0,0,0);
 34         VRayColor ReflectionColor(0,0,0);
 35         /*折射*/
 36         {
 37             VDouble SinB,CosB;
 38             VRayVector OutDirection=(-Sample.Normal).Refract(Sample.RefractionSinRatio,Direction,SinB,CosB);
 39             OutRatio=pow(CosB,Sample.RefractionRefindex);
 40             if(OutRatio>=Zero)
 41             {
 42                 VRayVector OutPosition=Sample.Position+OutDirection.Normalize().Scale(ReflectionOffsetScale);
 43                 OutColor=GetSampleColor(Objects,OutPosition,OutDirection,ReflectionCounter);
 44             }
 45         }
 46         /*反射*/
 47         {
 48             VBool ReflectionEnabled=Sample.ReflectionEnabled && ReflectionCounter>0 && !(1-OutRatio>=Zero);
 49             if(ReflectionEnabled)
 50             {
 51                 VRayVector ReflectionDirection=Sample.Normal.Reflect(Direction);
 52                 VRayVector ReflectionPosition=Sample.Position+ReflectionDirection.Normalize().Scale(ReflectionOffsetScale);
 53                 ReflectionColor=GetRefractionColor(Objects,Object,ReflectionPosition,ReflectionDirection,ReflectionCounter-1);
 54             }
 55         }
 56         /*混合*/
 57         OutColor=(OutColor.Scale(1-Sample.RefractionFaceRatio)+Sample.Color.Scale(Sample.RefractionFaceRatio));
 58         VRayColor MixColor=OutColor.Scale(OutRatio)+ReflectionColor.Scale(1-OutRatio);
 59         /*衰减*/
 60         return Sample.RefractionInternal.Scale(InternalRatio)+(MixColor*Sample.RefractionInternal).Scale(1-InternalRatio);
 61     }
 62     else
 63     {
 64         return VRayColor(0,0,0);
 65     }
 66 }
 67 
 68 VRayColor VL_RayRenderer::GetSampleColor(IVL_RayGeometry::UnmanagedList& Objects , VRayPoint Position , VRayVector Direction , VInt ReflectionCounter)
 69 {
 70     IVL_RayGeometry* Geometry=0;
 71     VL_RayObjectSample Sample;
 72     if(GetSample(Objects,Position,Direction,Geometry,Sample))
 73     {
 74         VRayColor Light(0,0,0);
 75         VRayColor Reflection(0,0,0);
 76         VRayColor Refraction(0,0,0);
 77         /*光源*/
 78         for(VInt i=0;i<Lights.GetCount();i++)
 79         {
 80             VRayColor LightColor=Lights[i]->GetLight(Sample.Position);
 81             VRayVector LightDirection=Lights[i]->GetDirection(Sample.Position).Normalize();
 82             if(LightDirection.Length()<Zero)
 83             {
 84                 Light+=LightColor;
 85             }
 86             else
 87             {
 88                 VBool Skip=false;
 89                 VL_RayObjectSample LookBackSample;
 90                 if(GetSample(Objects,Sample.Position-LightDirection.Normalize().Scale(ReflectionOffsetScale),-LightDirection,Geometry,LookBackSample))
 91                 {
 92                     VRayColor LookBackColor=Lights[i]->GetLight(LookBackSample.Position);
 93                     if(LookBackColor.R+LookBackColor.G+LookBackColor.B>Zero)
 94                     {
 95                         Skip=true;
 96                     }
 97                 }
 98                 if(!Skip)
 99                 {
100                     VDouble Scale=Sample.Normal.Normalize()*(-LightDirection);
101                     if(Scale>0)
102                     {
103                         Light+=LightColor.Scale(Scale);
104                     }
105                 }
106             }
107         }
108         /*反射*/
109         if(ReflectionCounter>0 && Sample.ReflectionEnabled)
110         {
111             VRayVector ReflectedDirection=Sample.Normal.Reflect(Direction.Scale(-Sample.DirectionScale));
112             VRayVector ReflectedPosition=Sample.Position+ReflectedDirection.Normalize().Scale(ReflectionOffsetScale);
113             Reflection=GetSampleColor(Objects,ReflectedPosition,ReflectedDirection,ReflectionCounter-1);
114         }
115         /*折射*/
116         if(Sample.RefractionEnabled)
117         {
118             VRayVector RefractionDirection=Sample.Normal.Refract(1/Sample.RefractionSinRatio,Direction);
119             if(RefractionDirection.Length()>Zero)
120             {
121                 VRayPoint RefractionPosition=Sample.Position+RefractionDirection.Normalize().Scale(ReflectionOffsetScale);
122                 Refraction=GetRefractionColor(Objects,Geometry,RefractionPosition,RefractionDirection,ReflectionCounter);
123                 Refraction=Sample.Color.Scale(Sample.RefractionFaceRatio)+Refraction.Scale(1-Sample.RefractionFaceRatio);
124             }
125         }
126         /*混合*/
127         return
128             (Light*Sample.Color).Scale(1-Sample.ReflectionRatio)+
129             (Reflection*Sample.ReflectionBase).Scale(Sample.ReflectionRatio)+
130             Refraction;
131     }
132     else
133     {
134         return VRayColor(0,0,0);
135     }
136 }
137 
138 void VL_RayRenderer::Render(IVL_RayGeometry::UnmanagedList& Objects , IVL_RayRenderingInformation* Information)
139 {
140     VL_WinBitmap::Ptr Buffer=new VL_WinBitmap(Information->GetBufferWidth(),Information->GetBufferHeight(),VL_WinBitmap::vbb24Bits,true);
141     VInt BufferWidth=Buffer->GetWidth();
142     VInt BufferHeight=Buffer->GetHeight();
143     for(VInt Y=0;Y<BufferHeight;Y++)
144     {
145         VByte* ScanLine=Buffer->GetScanLines()[Y];
146         for(VInt X=0;X<BufferWidth;X++)
147         {
148             VByte* Pixel=&ScanLine[X*3];
149             VDouble XRatio=(VDouble)(X*2-BufferWidth)/BufferWidth;
150             VDouble YRatio=(VDouble)(Y*2-BufferHeight)/BufferHeight;
151             VRayVector RenderingDirection=(FScreenCenter-FPosition)+FScreenRightVector.Scale(XRatio)+FScreenDownVector.Scale(YRatio);
152             VRayColor RenderingColor=GetSampleColor(Objects,FPosition,RenderingDirection,MaxReflectionLevelCount);
153             Pixel[0]=RangeColorChannel(RenderingColor.B);
154             Pixel[1]=RangeColorChannel(RenderingColor.G);
155             Pixel[2]=RangeColorChannel(RenderingColor.R);
156         }
157         Information->OnRendering(Buffer,Y+1);
158     }
159     Information->OnFinished(Buffer);
160 }
posted on 2009-01-22 06:02 陈梓瀚(vczh) 阅读(2083) 评论(2)  编辑 收藏 引用 所属分类: 3D

评论:
# re: 实现透明物体折射 2009-01-22 18:19 | abettor
太帅了!  回复  更多评论
  
# re: 实现透明物体折射 2009-04-15 07:25 | 小蚂蚁
GI是什么东西,你自己的写的图形引擎?  回复  更多评论
  

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