src/cv/tmesh.cal

{ SCCSid "$SunId$ LBL" }

{
        Interpolate triangle-mesh values using barycentric coordinates.

        A1              = Major axis (0==X, 1==Y, 2==Z)
        A2 through A10  = Surface normal perturbation matrix
or:
        A2 through A7   = Lookup in 2-dimensional pattern or texture
}
                                        { Get dominant coordinates }
bu = select(arg(1)+1, Py, Pz, Px);
bv = select(arg(1)+1, Pz, Px, Py);
                                        { Compute variables }
v1 = bu*arg( 2) + bv*arg( 3) + arg( 4);
v2 = bu*arg( 5) + bv*arg( 6) + arg( 7);
v3 = bu*arg( 8) + bv*arg( 9) + arg(10);
                                        { Surface normal perturbation }
nf = 1/sqrt(v1*v1 + v2*v2 + v3*v3);
dx = v1*nf - Nx;
dy = v2*nf - Ny;
dz = v3*nf - Nz;
                                        { Lookup table index }
u = v1;
v = v2;
Revision:	2.3
Committed:	Wed Jun 15 15:07:05 1994 UTC (30 years, 11 months ago) by greg
Branch:	MAIN
Changes since 2.2:	+6 -11 lines
Log Message:	further reduced complexity and size of barycentric calculation
#	User	Rev	Content
1	greg	2.1	{ SCCSid "$SunId$ LBL" }
2
3			{
4			Interpolate triangle-mesh values using barycentric coordinates.
5
6	greg	2.2	A1 = Major axis (0==X, 1==Y, 2==Z)
7	greg	2.3	A2 through A10 = Surface normal perturbation matrix
8	greg	2.1	or:
9	greg	2.3	A2 through A7 = Lookup in 2-dimensional pattern or texture
10	greg	2.1	}
11	greg	2.3	{ Get dominant coordinates }
12	greg	2.2	bu = select(arg(1)+1, Py, Pz, Px);
13			bv = select(arg(1)+1, Pz, Px, Py);
14	greg	2.1	{ Compute variables }
15	greg	2.3	v1 = buarg( 2) + bvarg( 3) + arg( 4);
16			v2 = buarg( 5) + bvarg( 6) + arg( 7);
17			v3 = buarg( 8) + bvarg( 9) + arg(10);
18	greg	2.1	{ Surface normal perturbation }
19			nf = 1/sqrt(v1v1 + v2v2 + v3*v3);
20			dx = v1*nf - Nx;
21			dy = v2*nf - Ny;
22			dz = v3*nf - Nz;
23			{ Lookup table index }
24			u = v1;
25			v = v2;