bdiscoe@tybalt.caltech.edu (Ben W. Discoe) (11/07/89)
I'm writing a structed graphics program that allows unlimited zoom
(simply changing scaling factors) and until recently could count on the
automatic clipping the graphics library does using the Layer limits.
However, when I start to draw line WAY off the screen (>several thousand
pixels) two things start happening:
1) the lines become jagged when they appear on the screen
2) eventually the machine dies or the program freezes in a state
of intense CPU usage.
I realize what I should do is test the endpoints of each line I draw
and not draw the ones too far off, however, I'd like to know a few things:
1) What are the exact limits to the gfx lib clipping?
2) Does is make a difference if the number you pass "Draw()"
is great than a WORD variable will allow?
3) Why does the machine die? Does it have to do with the line
drawing being done in hardware?
I couldn't find anything in the RKMs about this and I hope it isn't a
case of RTFM. Thanks much,
Ben "struggling starving student stereotype"owl@drycas.club.cc.cmu.edu (11/08/89)
In article <12540@cit-vax.Caltech.Edu>, bdiscoe@tybalt.caltech.edu (Ben W. Discoe) writes: > [...] > However, when I start to draw line WAY off the screen (>several thousand > pixels) two things start happening: > > 1) the lines become jagged when they appear on the screen > 2) eventually the machine dies or the program freezes in a state > of intense CPU usage. I had the same thing happen, in a function drawing program ... > I realize what I should do is test the endpoints of each line I draw > and not draw the ones too far off, however, I'd like to know a few things: > > 1) What are the exact limits to the gfx lib clipping? > 2) Does is make a difference if the number you pass "Draw()" > is great than a WORD variable will allow? Yes ... If you keep your values inside the limits for a WORD all will work well. > I couldn't find anything in the RKMs about this and I hope it isn't a > case of RTFM. Thanks much, > Ben "struggling starving student stereotype" David Gay Now at: dg3i+@andrew.cmu.edu after hopping across the pond ...