Functions | |
void | Edit_Grid (HC_KEY key, const char *type, const HC_POINT *origin, const HC_POINT *ref1, const HC_POINT *ref2, int count1, int count2) |
void Edit_Grid | ( | HC_KEY | key, | |
const char * | type, | |||
const HC_POINT * | origin, | |||
const HC_POINT * | ref1, | |||
const HC_POINT * | ref2, | |||
int | count1, | |||
int | count2 | |||
) |
Edits a grid object as it sits in the database.
key | - Key to a grid object. | |
type | - Special constant (see below). | |
origin | - An x-y-z triplet for the coordinates of the "start point" of the grid. (A simple array of three elements may also be used in most languages.) Passed by reference always. | |
ref1 | - An x-y-z triplet for the coordinates of the first point "to the right of" origin. See below for details. Passed by reference always. | |
ref2 | - An x-y-z triplet for the coordinates of the first point "above" origin. See below for details. Passed by reference always. | |
count1 | - The number of grid units along the ref1 dimension. | |
count2 | - The number of grid units along the ref2 dimension. |
quadrilateral
A quadrilateral unit is formed as:
(origin, ref1, ref1 + ref2 - origin, ref2).
If count1 is positive, the number of units is laid down along the ref1 axis starting at origin. If it is negative, the number of units is laid down along the ref1 axis and an additional count1 number of units is laid down along the negative ref1 axis. The entire count1 assembly is duplicated along the ref2 axis. If count2 is negative, the repetitions go both ways from the origin.
If both count1 and count2 are zero, the quadrilateral grid is infinite in extent. The system will make the appropriate optimizations when the grid is seen in perspective.
radial
A "pie wedge" is formed as (origin, ref1, ref2). The pie wedge is drawn radially count1 times, and circumferentially count2 times.
If count1 is given as zero, the radial grid is infinite in extent. The system will make the appropriate optimizations when the grid is seen in perspective.
Grids are grouped with shells and meshes for rendering purposes. The rendition of the interior of the grid can be adjusted with changes to face Pattern. The edges can be adjusted with Edge Pattern and Weight. The vertices can be adjusted with Marker Size and Symbol. The faces, edges, and markers can all be controlled with Visibility and Selectability.
When not using 3-D "hidden surface" mode, the routine Bring_To_Front() can be helpful in forcing geometries to be drawn reliably on top of a grid.