A lot to ask for....

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Started by Kheteris December 16, 2003 02:07 PM

8 comments, last by Kheteris 20 years, 4 months ago

122

Author

December 16, 2003 02:07 PM

Yo, in my program I have two boxes on the screen, but sometimes when I start up the program they don't appear... before I put up the code, does anyone know what I may be doing wrong? They appear sometimes...

Edit : Oh yeah, if you can't think of a reason, is there a way I could error trap it? something like...



if (GL_POLYGON == false)
    return 0;

I know that's wrong, but I think you get the idea

[edited by - Kheteris on December 16, 2003 3:12:33 PM]

Living Monstrosity

122

December 16, 2003 03:06 PM

Do you allocate memory for the boxes during runtime?
If so, the memory might nog be allocated correctly (or not at all).
Also be sure to set all variables to a default, for example if you create a float array : float a[100];, the data is not automatically set to 0.0f, so if you''d do this:

a[2]=100;
a[3]=75;
DrawRectangle(a[0],a[1],a[2],a[3]);

It might sometimes result in a rectangle from (0.0f,0.0f) to (100,75) and sometimes in a completely diffirent origin, so it might be an invalid rectangle.

- growl -

Kheteris

122

Author

December 17, 2003 03:21 PM

Well, I don''t use an array, but I do use variables, which the computer randomly selects (there is no default) and when they are constantly changing... could this be the problem?

glVertex3f(x+250,wspeed-30,z);

DarkNebula

150

December 17, 2003 03:26 PM

Well where is the camera pointing to? What''s the projection your using too.

- DarkNebula

Kheteris

122

Author

December 17, 2003 03:29 PM

it's just facing straight, it is 2d

edit: i see other objects aswell, but the boxes don't always appear

[edited by - kheteris on December 17, 2003 4:30:27 PM]

eldee

122

December 17, 2003 03:44 PM

quote:Original post by Kheteris
Well, I don''t use an array, but I do use variables, which the computer randomly selects (there is no default) and when they are constantly changing... could this be the problem?

glVertex3f(x+250,wspeed-30,z);

you realize that a.) 250 and 30 are not floats, and b.) 250 and 30 are going to be WAAAAAY offscreen if you''re using a standard projection matrix

-eldee;another space monkey;[ Forced Evolution Studios ]

Kheteris

122

Author

December 17, 2003 06:00 PM

With my projection they fit just fine

, and I can zoom in and out if I need to... but let me check w/ 250 and -30

Edit: [few hours after post] well I am unable to change it now but does someone believe that if I add .0f to the end it would possible end the randomness?

[edited by - Kheteris on December 17, 2003 9:44:00 PM]

RipTorn

722

December 17, 2003 09:21 PM

float + int = float, so I don''t think thats the problem.

I think Living Monstrosity is probably right. you need to make sure every variable you use is initalized. Make sure the likes of x and y are set to proper values. and if not sure, step-through debug it.

| - Project-X - | - adDeath - | - my windows XP theme - | - email me - |

Leyder Dylan

122

December 18, 2003 11:01 AM

What about the perspective of your window ?

// Calculate The Aspect Ratio Of The WindowgluPerspective(45.0f,(GLfloat) width / (GLfloat) height, 0.1f, 5000.0f);

Cuz if the last variable (5000.0f in this example) is at 10 and your vertice at 50 or more, your cube will be never visible.

========================
Leyder Dylan (dylan.leyder@slug-production.be.tf
http://users.skynet.be/fa550206/Slug-Production/Index.htm/

[edited by - Leyder Dylan on December 18, 2003 12:01:47 PM]

========================Leyder Dylan (dylan.leyder@slug-production.be.tf http://users.skynet.be/fa550206/Slug-Production/Index.htm/

Leyder Dylan

122

December 18, 2003 11:03 AM

Damned, I always forgot how to add source code in a post. How is it ?

Do I need to begin with and finish with (without the space)

My brain is overflowed ...

========================
Leyder Dylan (dylan.leyder@slug-production.be.tf
http://users.skynet.be/fa550206/Slug-Production/Index.htm/

========================Leyder Dylan (dylan.leyder@slug-production.be.tf http://users.skynet.be/fa550206/Slug-Production/Index.htm/

A lot to ask for....

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