Patch Routines.

patchbasis(tbasis, ubasis)

Define the t and u basis matrices of a patch.

```    Fortran:
subroutine patchbasis(tbasis, ubasis)
real tbasis(4, 4), ubasis(4, 4)
C:
patchbasis(tbasis, ubasis)
float     tbasis[4][4], ubasis[4][4];

Pascal:
procedure PatchBasis(tbasis, ubasis: Matrix44_t)
```

patchprecision(tseg, useg)

Set the minimum number of line segments making up curves in a patch.

```    Fortran:
subroutine patchprecision(tseg, useg)
integer tseg, useg
C:
patchprecision(tseg, useg)
int     tseg, useg;

Pascal:
procedure PatchPrecision(tseg, useg: integer)
```

patchcurves(nt, nu)

Set the number of curves making up a patch.

```    Fortran:
subroutine patchcurves(nt, nu)
integer nt, nu
C:
patchcurves(nt, nu)
int     nt, nu;

Pascal:
procedure PatchCurves(nt, nu: integer)
```

rpatch(gx, gy, gz, gw)

Draws a rational patch in the current basis, according to the geometry matrices gx, gy, gz, and gw.

```    Fortran:
subroutine rpatch(gx, gy, gz, gw)
real  gx(4,4), gy(4,4), gz(4,4), gw(4,4)
C:
rpatch(gx, gy, gz, gw)
float  gx[4][4], gy[4][4], gz[4][4], gw[4][4];

Pascal:
procedure Rpatch(gx, gy, gz, gw: Matrix44_t)
```

patch(gx, gy, gz)

Draws a patch in the current basis, according to the geometry matrices gx, gy, and gz.

```    Fortran:
subroutine patch(gx, gy, gz)
real  gx(4,4), gy(4,4), gz(4,4)
C:
patch(gx, gy, gz)
float  gx[4][4], gy[4][4], gz[4][4];

Pascal:
procedure Patch(gx, gy, gz: Matrix44_t)
```