Changeset 1700

Timestamp:

10/30/06 13:47:11 (18 years ago)

Author:

szirmay

Message:

 

File:

• GTP/trunk/App/Demos/Illum/Ogre/Media/materials/programs/GameTools_Localized_EnvMap.hlsl (modified) (2 diffs)

GTP/trunk/App/Demos/Illum/Ogre/Media/materials/programs/GameTools_Localized_EnvMap.hlsl

@@ -49 +49 @@
 #define LIN_ITERATIONCOUNT 5
 #define SECANT_ITERATIONCOUNT 0
-
+/*
 float3 Hit(float3 x, float3 R, samplerCUBE mp)
 {
@@ -71 +71 @@
                 float3 point = dir * dist;
                                 
+                if( dot(N, point) > d)//undershooting
+                {
+                        under = point;                  
+                }
+                else                            //overshooting
+                {
+                        over = point;                   
+                        i = LIN_ITERATIONCOUNT;
+                }       
+        }
+        
+        float3 dirUn = normalize(under);
+        float3 dirOv = normalize(over);
+        float tun = d / dot(N, dirUn);
+        float pun = tun / length(under);
+        float dun = length(tun * dirUn - x);
+        float tov = d / dot(N, dirOv);
+        float pov = tov / length(over);
+        float dov = length(tov * dirOv - x);
+        float tl = (d - dot(N, over)) / dot(N, under - over);
+        float3 l = over + tl * (under - over);
+        float dl = length(l - x);
+                
+        //secant iteration
+        for( int i = 0; i < SECANT_ITERATIONCOUNT; i++ )
+        {
+                float llp = length( l ) / readDistanceCubeMap( mp, l);          // |l|/|l’|
+                if ( llp < 0.999f )                                                                     // undershooting
+                {
+                        dun = dl; pun = llp;                                                    // last undershooting
+                        dl += ( dl - dov ) * ( 1 - llp ) / ( llp - pov );       // eq. 3
+                } else if ( llp > 1.001f )                                                      // overshooting
+                {
+                        dov = dl; pov = llp;                                                    // last overshooting
+                        dl += ( dl - dun ) * ( 1 - llp ) / ( llp - pun );// eq. 3
+                }
+                l = x + R * dl;                                                                         // ray equation
+        }
+        
+        return l;               
+        return over;    
+        return (under + over)/2.0;
+}
+*/
+float3 Hit(float3 x, float3 R, samplerCUBE mp)
+{
+        R = normalize(R);
+        float3 xNorm = normalize(x);
+        float3 dt = (R - xNorm) / (float) LIN_ITERATIONCOUNT;
+        float dx = length(cross(R,x));
+        
+        float3 pN = normalize(cross(R, xNorm));
+        float3 N = normalize(cross(pN,R));
+        float d = dot(x, N);    
+        
+        float3 under = xNorm * readDistanceCubeMap(mp, x);
+        float3 over = R * readDistanceCubeMap(mp, R);
+        
+        //linear iteration      
+        for(int i = 1; i < LIN_ITERATIONCOUNT; i++)
+        {
+                float3 ldir = normalize(xNorm + dt * i);
+                float lL = readDistanceCubeMap( mp, dir);
+                float3 l_ = dir * dist;
+                float alpha = (dot(x, l_) - dot(R, l_) * dot(x, R)) / (lL * lL - dot(R, l_) * dot(R, l_));
+                float d = dot(l_, R) * alpha - dot(x, R);
+                
                 if( dot(N, point) > d)//undershooting
                 {