// zslice2 

int dataSize = 11;
int imgSize = 200;
vec3 orig = [0.0, 0.0, 5.0];
vec3 cVec = [0.0, 1.0, 0.0];
vec3 rVec = [1.0, 0.0, 0.0];
// HEY (bug), next line causes:
//  uncaught exception Fail [Fail: Error in compiling zslice2.diderot]
//  raised at driver/main.sml:31.39-31.76
// but is this not valid syntax for creating field in one shot?
//field#2(3)[] F = (load("../data/zimg112.nrrd")) ⊛ bspln3;
// It is valid syntax, but there is a bug in the conversion from HighIL to MidIL

image(3)[] img = load("../data/zimg112.nrrd");
//field#2(3)[] F = img ⊛ bspln3;
//field#2(3)[] F = img ⊛ ctmr;
//field#0(3)[] F = img ⊛ tent;
field#1(3)[] F = img ⊛ c1tent;

strand RayCast (int row, int col)
{
    real rr = lerp(-0.5, real(dataSize)-0.5, -0.5, real(row), real(imgSize)-0.5);
    real cc = lerp(-0.5, real(dataSize)-0.5, -0.5, real(col), real(imgSize)-0.5);
    vec3 pos = orig + rr*rVec + cc*cVec;
    output real val = -∞; 

    update
    {
        if (inside (pos,F)) {
          val = F@pos;
	}
        stabilize;
    }
}

initially [ RayCast(r, c) | r in 0..(imgSize-1), c in 0..(imgSize-1) ];