# Q why do I get: uninitialized constant GLUT::BITMAP\_8\_BY\_13

**URL:** <https://www.ruby-forum.com/t/q-why-do-i-get-uninitialized-constant-glut-bitmap-8-by-13/117708>\
**Category:** Ruby\
**Created:** [October 19, 2007, 4:14pm UTC](https://www.ruby-forum.com/t/q-why-do-i-get-uninitialized-constant-glut-bitmap-8-by-13/117708 "2007-10-19T16:14:22Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Steffen\_winther\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ad7895/32.png) [@Steffen\_winther\_S](https://www.ruby-forum.com/u/Steffen_winther_S)\
**Post date:** [October 19, 2007, 4:14pm UTC](https://www.ruby-forum.com/t/q-why-do-i-get-uninitialized-constant-glut-bitmap-8-by-13/117708/1 "2007-10-19T16:14:22Z")

</div>

Hi

Doing a little open GL from Ruby fails on my production server (Ubuntu)  
but not on my labtop (Fedora) even though runby-opengl is installed  
without any complaints on both machines.

On Ubuntu I get this error running my script:

# ./gxaamta-stdin.rb:392:in `render’: uninitialized constant

GLUT::BITMAP\_8\_BY\_13 (NameError)  
…

# ruby -v

ruby 1.8.2 (2004-12-25) [i686-linux]

# gem -v

0.9.4

# gem list --local

\*\*\* LOCAL GEMS \*\*\*

mkrf (0.2.2)  
Generate Rakefiles to Build C Extensions to Ruby

needle (1.3.0)  
Needle is a Dependency Injection/Inversion of Control container for  
Ruby. It supports both type-2 (setter) and type-3 (constructor)  
injection. It takes advantage of the dynamic nature of Ruby to  
provide a rich and flexible approach to injecting dependencies.

rake (0.7.3)  
Ruby based make-like utility.

ruby-opengl (0.40.1)  
OpenGL Interface for Ruby

sources (0.0.1)  
This package provides download sources for remote gem installation

Only different is on my laptop I have:  
$ ruby -v  
ruby 1.8.6 (2007-09-24 patchlevel 111) [i386-linux]  
[stws@labtop ruby]$ gem -v  
0.9.4  
$ gem list --local  
… same as above

looking into /usr/lib/ruby/gems/1.8/gems/ruby-opengl-0.40.1, I find  
BITMAP\_\* in lib/glut.so on both machines, only why doesn’t it seem to be  
on my Ubuntu, any clues/hints very welcome?

BTW Where are a compiled gem found and loaded by ruby’ require  
statement?

---

<div class="post-metadata">

**Author:** ![Steffen\_winther\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ad7895/32.png) [@Steffen\_winther\_S](https://www.ruby-forum.com/u/Steffen_winther_S)\
**Post date:** [October 19, 2007, 8:25pm UTC](https://www.ruby-forum.com/t/q-why-do-i-get-uninitialized-constant-glut-bitmap-8-by-13/117708/2 "2007-10-19T20:25:04Z")

</div>

On 10/19/07, Steffen winther Soerensen [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> Hi
> 
> Doing a little open GL from Ruby fails on my production server (Ubuntu)  
> but not on my labtop (Fedora) even though runby-opengl is installed  
> without any complaints on both machines.

I am able to run ruby-opengl examples on my Ubuntu desktop.

Linux 2.6.20-16-generic #2 SMP Sun Sep 23 19:50:39 UTC 2007 i686  
GNU/Linux

ruby 1.8.6 (2007-03-13 patchlevel 0) [i686-linux]

The example I ran start as follows:  
#!/usr/bin/env ruby -rubygems

# Name: nehe\_lesson05.rb

# Purpose: An implementation of NeHe’s OpenGL Lesson #05

# using ruby-opengl ([http://nehe.gamedev.net/](http://nehe.gamedev.net/))

# 

require “gl”  
require “glu”  
require “glut”  
require “mathn”

# Add GL and GLUT namespaces in to make porting easier

include Gl  
include Glu  
include Glut

Prasad