1 |
greg |
2.5 |
{ RCSid: $Id: tmesh.cal,v 2.4 2003/02/22 02:07:23 greg Exp $ } |
2 |
greg |
2.1 |
{ |
3 |
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Interpolate triangle-mesh values using barycentric coordinates. |
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5 |
greg |
2.2 |
A1 = Major axis (0==X, 1==Y, 2==Z) |
6 |
greg |
2.3 |
A2 through A10 = Surface normal perturbation matrix |
7 |
greg |
2.1 |
or: |
8 |
greg |
2.3 |
A2 through A7 = Lookup in 2-dimensional pattern or texture |
9 |
greg |
2.1 |
} |
10 |
greg |
2.3 |
{ Get dominant coordinates } |
11 |
greg |
2.2 |
bu = select(arg(1)+1, Py, Pz, Px); |
12 |
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bv = select(arg(1)+1, Pz, Px, Py); |
13 |
greg |
2.1 |
{ Compute variables } |
14 |
greg |
2.3 |
v1 = bu*arg( 2) + bv*arg( 3) + arg( 4); |
15 |
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v2 = bu*arg( 5) + bv*arg( 6) + arg( 7); |
16 |
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v3 = bu*arg( 8) + bv*arg( 9) + arg(10); |
17 |
greg |
2.1 |
{ Surface normal perturbation } |
18 |
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nf = 1/sqrt(v1*v1 + v2*v2 + v3*v3); |
19 |
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dx = v1*nf - Nx; |
20 |
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dy = v2*nf - Ny; |
21 |
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dz = v3*nf - Nz; |
22 |
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{ Lookup table index } |
23 |
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u = v1; |
24 |
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v = v2; |