// vr-MIP.diderot // // maximum intensity projection in Diderot // input string dataFile; // name of dataset input real stepSz = 0.1; // size of steps // e.g. 0.1 input vec3 eye; // location of eye point // e.g. txs: (25,15,10) // vox1,x: (-8,2,2) // vox1,y: (2,-8,2) // vox1,z: (2,2,-8) input vec3 orig; // location of pixel (0,0) // e.g. txs: (8.83877,2.5911,7.65275) // vox1,x: (0,3.4036,3.4036) // vox1,y: (0.596402,0,3.4036) // vox1,z: (3.4036,3.4036,0) input vec3 cVec; // vector between pixels horizontally // e.g. txs: (-0.0151831,0.0278357,0) // vox1,x: (0,-0.014036,0) // vox1,y: (0.014036,0,0) // vox1,z: (-0.014036,0,0) input vec3 rVec; // vector between pixels vertically // e.g. txs: (0.0074887,0.00408474,-0.0305383) // vox1,x: (0,0,-0.014036) // vox1,y: (0,0,-0.014036) // vox1,z: (0,-0.014036,0) image(3)[] img = load (dataFile); //field#1(3)[] F = convolve (bspln3, img); field#2(3)[] F = img ⊛ bspln3; actor RayCast (int row, int col) { vec3 pos = orig + real(row)*rVec + real(col)*cVec; vec3 dir = (pos - eye)/|pos - eye|; real t = 0.0; output real maxval = -∞; update { pos = pos + stepSz*dir; if (inside (pos,F)) { real val = F@pos; maxval = max(val, maxval); } if (t > 20.0) stabilize; t = t + stepSz; } /* render: output maxval */ } initially [ RayCast(r, c) | r in 0..199, c in 0..199 ];