pick(3G)pick(3G)NAMEpick - puts the system in picking mode
C SPECIFICATION
void pick(buffer, numnames)
short buffer[];
long numnames;
PARAMETERS
buffer expects the array to use for storing names.
numnames expects the maximum number of names to store. This must not
exceed the number of elements in buffer.
DESCRIPTIONpick facilitates the cursor as a pointing object. When you draw an image
in picking mode, nothing is drawn. It places a special viewing matrix on
the stack, which discards everything in the image that does not intersect
a small region around the cursor origin.
The graphical items that intersect the picking region are hits and store
the contents of the name stack in buffer. Picking does not work if you
issue a new viewport in picking mode.
SEE ALSO
endpick, endselect, gselect, picksize, pushname, popname, loadname
NOTE
This routine is available only in immediate mode.
In order to pick a large point or a wide line in picking mode, the
selecting region must intersect the displayed point center or the
displayed line center respectively. The displayed point center is the
imaginary point of size 1 specified by the same vertex as the displayed
point. The displayed line center is the imaginary line of width 1
specified by the same vertices as the displayed line. In case of a very
large point or very wide line, you may want to consider drawing a filled
circle or a filled rectangle respectively instead.
Page 1
