VARKON Version 1.15 1997-10-24

gettopp - Procedure

Get topological patch from GM


Description

Reads topological patch data from GM.

Syntax

gettopp(sur_id, iu, iv, geo_type, u1, u2, v1, v2)

REF	sur_id;
INT	iu;
INT	iv;
INT	geo_type;
FLOAT	u1;
FLOAT	v1;
FLOAT	u2;
FLOAT	v2;

Principal parameters

sur_id	- Global identity of surface to which the patch belongs
iu	- Patch number in U direction
iv	- Patch number in V direction
geo_type	- The kind of corresponding geometrical patch
u1	- Start parameter value in U direction
u2	- End parameter value in U direction
v1	- Start parameter value in V direction
v2	- End parameter value in V direction

Optional parameters

None.

Comments

The patch address for the start patch is (iu,iv)= (1,1).

Patch parameter values are normally u1= 0.0, v1= 1.0, v1= 0.0 and v2= 1.0 but values may be different for trimmed patches.

Geometrical patches may be of the following types:

0 = Null patch
1 = Non rational bicubic
2 = Rational bicubic
3 = Conic lofting
4 = Plane facett
5 = Topological
6 = Procedural
7 = Coons
8 = Consurf