uniform vec4 vViewPosition;
uniform float BumpDepth; 
uniform vec4 lightPos;

attribute vec3 rm_Tangent; 
attribute vec3 rm_Binormal;

varying vec3 TexCoord;
varying vec3 tanEyeVec;
varying vec3 tanLightVec;

void main( void )
{
    // Project position into screen space 
   // and pass through texture coordinate
    gl_Position = ftransform();
    TexCoord    = vec3(gl_MultiTexCoord0.xy, 1.0);

   // Transform the eye vector into tangent space.
   // Adjust the slope in tangent space based on bump depth
   vec3 eyeVec = (vViewPosition.xyz - gl_Vertex.xyz);
   tanEyeVec.x = dot(rm_Tangent, eyeVec);
   tanEyeVec.y = dot(rm_Binormal, eyeVec);
   tanEyeVec.z = -1.0/BumpDepth * dot(gl_Normal, eyeVec);
   
   // Transform the light vector into tangent space.
   // We will use this later for tangent-space normal mapping
   vec3 lightVec = (lightPos.xzy - gl_Vertex.xzy);
   tanLightVec.x = dot(rm_Tangent, lightVec);
   tanLightVec.y = dot(rm_Binormal, lightVec);
   tanLightVec.z = dot(gl_Normal, lightVec);
    
}

#define NUM_ITERATIONS 2

uniform sampler2D colorSampler;
uniform sampler3D heightSampler;
uniform sampler2D normalSampler; 
// this is the depth of 3dTexture divided by the width of the 3dTexture
// 8/256 in my case
uniform float normalizationFactor; 

varying vec3 TexCoord;
varying vec3 tanEyeVec;
varying vec3 tanLightVec;

void main( void )
{
   // Normalize the offset vector in texture space.
   // The normalization factor ensures we are normalized with respect
   // to a distance which is defined in terms of pixels.
   vec3 offset = normalize(tanEyeVec);
   offset *= normalizationFactor;
   vec3 texCoord = TexCoord;
   // March a ray
   
   for (int i = 0; i < NUM_ITERATIONS; i++) {
      float distance2Trace = texture3D(heightSampler, texCoord).r;
      texCoord += distance2Trace * offset;
   }
   
   // Compute derivatives of unperturbed texcoords.
   // This is because the offset texcoords will have discontinuities
   // which lead to incorrect filtering.
   //vec2 dx = dFdx(TexCoord.xy);
   //vec2 dy = dFdy(TexCoord.xy);
   // Do bump-mapped lighting in tangent space.
   // ‘normalTex’ stores tangent-space normals remapped 
   // into the range [0, 1].
   vec3 tanNormal = 2.0 * texture2D(normalSampler, texCoord.xy).xyz - 1.0;
   //vec3 tanNormal = 2.0 * texture2D(normalSampler, texCoord.xy, dx, dy) - 1.0;
   vec3 tanLightVecN = normalize(tanLightVec);
   float diffuse = dot(tanNormal, tanLightVecN);
   // Multiply diffuse lighting by texture color
   //gl_FragColor = diffuse * texture2D(colorSampler, texCoord.xy, dx, dy);
   gl_FragColor = diffuse * texture2D(colorSampler, texCoord.xy);
    
}

# stone-dismap.tai# AtlasCreationTool.exe -nomipmap -volume -o stone-dismap## <filename>		<atlas filename>, <atlas idx>, <atlas type>, <woffset>, <hoffset>, <depth offset>, <width>, <height>## Texture <filename> can be found in texture atlas <atlas filename>, i.e., # stone-dismap<idx>.dds of <atlas type> type with texture coordinates boundary given by:#   A = ( <woffset>, <hoffset> )#   B = ( <woffset> + <width>, <hoffset> + <height> )## where coordinates (0,0) and (1,1) of the original texture map correspond# to coordinates A and B, respectively, in the texture atlas.# If the atlas is a volume texture then <depth offset> is the w-coordinate# to use the access the appropriate slice in the volume atlas.heightMap00.png		stone-dismap0.dds, 0, Volume, 0.000000, 0.000000, 0.062500, 1.000000, 1.000000heightMap01.png		stone-dismap0.dds, 0, Volume, 0.000000, 0.000000, 0.187500, 1.000000, 1.000000heightMap02.png		stone-dismap0.dds, 0, Volume, 0.000000, 0.000000, 0.312500, 1.000000, 1.000000heightMap03.png		stone-dismap0.dds, 0, Volume, 0.000000, 0.000000, 0.437500, 1.000000, 1.000000heightMap04.png		stone-dismap0.dds, 0, Volume, 0.000000, 0.000000, 0.562500, 1.000000, 1.000000heightMap05.png		stone-dismap0.dds, 0, Volume, 0.000000, 0.000000, 0.687500, 1.000000, 1.000000heightMap06.png		stone-dismap0.dds, 0, Volume, 0.000000, 0.000000, 0.812500, 1.000000, 1.000000heightMap07.png		stone-dismap0.dds, 0, Volume, 0.000000, 0.000000, 0.937500, 1.000000, 1.000000