1 uniform sampler3D vol_tex;

2 uniform sampler1D xfer_tex;

3

4 void main()

5 {

6 vec3 tc = gl_TexCoord[0].xyz;

7 float max_manh_dist = max(tc.x, max(tc.y, tc.z));

8 float min_manh_dist = min(tc.x, min(tc.y, tc.z));

9 float border = step(0.0, min_manh_dist) * (1.0 - step(1.0, max_manh_dist));

10

11 vec4 voxel = texture3D(vol_tex, gl_TexCoord[0].xyz);

12 vec4 color = texture1D(xfer_tex, voxel.a);

13

14 float alpha = color.a * border;

15 if(alpha < 0.001) discard;

16

17 gl_FragColor.rgb = voxel.rgb;

18 gl_FragColor.a = alpha;

19 }