How to set borders for the screen?

OpenGL OpenGL: Basic Coding
1

Hello!

I am programming with Borland C++ Builder5.

I have a 3D cube that i can move around with my Keys. So if i do that and the Cube reaches the border of the Screen(or Form in window-mode) it doesn’t stop and goes on until its gone.

So how can i set borders for my screen?
Is there a OpenGL-Function to set this?

Thanks for Help!!

2

The short answer to your question is no' - there is not border function such as you describe. This is perhaps a problem withcollision detection’ in that you must check to see whether or not the cube is still within the viewing frustum after you have moved its position.

Do a search on frustum intersections with cube on google or something.

3

Hi!

Thanks for your reply. I’ll have have a look at the frustum thing.

Thanks again!

4

If you want to keep it for going of the screen then setup a boundry like this.

example:

if ( cube_x > x_boundry_right) cube_x = x_boundry_right;
if ( cube_x < x_boundry_left) cube_x = x_boundry_left;

repeat check for y and z.

If you want to just bounce around the screen, then add a direction varible.

if (cube_x > x_boundry_right) cube_direction = Left; // if hit right boundry, move now to the left

hope this helps

Originally posted by Clouddancer:
[b]Hello!

I am programming with Borland C++ Builder5.

I have a 3D cube that i can move around with my Keys. So if i do that and the Cube reaches the border of the Screen(or Form in window-mode) it doesn’t stop and goes on until its gone.

So how can i set borders for my screen?
Is there a OpenGL-Function to set this?

Thanks for Help!![/b]

5

Hi!

Thanks for this input! I’ll have a look at it and try this out like that. hope i’ll get it running:-)