disappearing objects

OpenGL OpenGL: Basic Coding
1

i am writing a shooter and i encountered a
funny problem - as i move further away from objects i draw they start disappearing on me.

when i’m close to the objects they look fine,
but as i move away, edges start disappearing then faces disappear until finally the entire object disappears -
did anyone encounter such a problem or might have an idea what’s wrong with my program.

thanks
alan.

2

They are probably being culled at the far clip plane. Set the value for the high clip plane to a higher number.

j

3

thanks, but that’s not it.

you see, first i draw the walls of the game and then i draw the detailed objects that are in the game - only the detail objects have this problem - the walls that are behind the objects are not effected for some reason - so it’s not the clipping plane.

any other ideas???

alan

4

Hmmmm… That is strange.

Maybe polygon draw mode, or something like that?

Other than something like that, I have no idea.

Maybe a screenshot would help.

j

5

i don’t know how to get screenshots,

the wierd thing is that the polygons don’t disappear at once, they don’t “blink” out of existance, the polygons paritally disappear, then reappear , then disappear again.
wierd huh???

i know the problem is with my drawing function, because i tried drawing a regular cube next to my objects from outside the drawing function - and the cube stayed intact!!!

by the way, if you can tell me how i can get a screenshot, i’d be more than happy send it to you.

thanks for trying to help,
but it looks like a long day of dubugging for me.

alan

6

never mind - i solved my problem.

i don’t know why it works, but it works.
(i simply moved the draw of the detailed objects to be the last thing drawn - and it solved it - i don’t know why it made a difference because i used a depth buffer and it shouldn’t have mattered).

thanks alan

7

[QUOTE]Originally posted by alan:
[b]i don’t know how to get screenshots,

If you are using windoze (perhaps Linux as well?) then shift-printscreen will copy a bmp of your screen to the clipboard. Then paste it into any bmp viewer, paint for example.

8

Probably that was z-aliasing. AFAIK With nearplane=1,farplane=100 75=85. So detailed objects might be not well-rendered.