| 2 |
|
{ |
| 3 |
|
Compute patterns for ambient position markers |
| 4 |
|
} |
| 5 |
+ |
odd(n) : .5*n - floor(.5*n) - .25; |
| 6 |
+ |
posangle(a) : if(-a, a + 2*PI, a) / DEGREE; |
| 7 |
|
{ Relative hit point } |
| 8 |
|
rpx = Px - arg(1); |
| 9 |
|
rpy = Py - arg(2); |
| 12 |
|
{ Calculation of directional gradient pattern } |
| 13 |
|
ndx = arg(4); ndy = arg(5); ndz = arg(6); |
| 14 |
|
dgx = arg(7); dgy = arg(8); dgz = arg(9); |
| 15 |
< |
dg = sqrt(dgx*dgx + dgy*dgy + dgz*dgz); |
| 16 |
< |
dux = (ndy*dgz - ndz*dgy)/dg; |
| 17 |
< |
duy = (ndz*dgx - ndx*dgz)/dg; |
| 18 |
< |
duz = (ndx*dgy - ndy*dgx)/dg; |
| 19 |
< |
dsine = (dux*rpx + duy*rpy + duz*rpz)/sqrt(rpx*rpx + rpy*rpy + rpz*rpz); |
| 18 |
< |
dirfunc = bound(0, 1 + dg*dsine, 2); |
| 15 |
> |
rdx = ndy*rpz - ndz*rpy; |
| 16 |
> |
rdy = ndz*rpx - ndx*rpz; |
| 17 |
> |
rdz = ndx*rpy - ndy*rpx; |
| 18 |
> |
dgrad = (rdx*dgx + rdy*dgy + rdz*dgz)/sqrt(rpx*rpx + rpy*rpy + rpz*rpz); |
| 19 |
> |
dirfunc = bound(0, 1 + dgrad, 2); |
| 20 |
|
|
| 21 |
|
{ Calculation of positional gradient pattern } |
| 22 |
|
pgx = arg(4); pgy = arg(5); pgz = arg(6); |
| 23 |
|
posfunc = bound(0, 1 + (pgx*rpx + pgy*rpy + pgz*rpz), 2); |
| 24 |
+ |
{ corral flags and associated pattern } |
| 25 |
+ |
ux = arg(4); uy = arg(5); uz = arg(6); |
| 26 |
+ |
cflags = arg(7); |
| 27 |
+ |
vx = Ny*uz - Nz*uy; |
| 28 |
+ |
vy = Nz*ux - Nx*uz; |
| 29 |
+ |
vz = Nx*uy - Ny*ux; |
| 30 |
+ |
cflg(i) = if(odd(floor( cflags / 2^i )), 1, -1); |
| 31 |
+ |
corralled = cflg(floor(32/360*posangle( |
| 32 |
+ |
atan2(rpx*vx+rpy*vy+rpz*vz, rpx*ux+rpy*uy+rpz*uz) ))); |
| 33 |
|
|
| 34 |
|
{ Calculation of ellipse stencil for base } |
| 35 |
|
usx = arg(4); usy = arg(5); usz = arg(6); |
