opengl-core

OpenGL core profile and extension bindings for Ruby 2.x.

$ gem install opengl-core

And in your script:

require 'opengl-core'

Job done, have fun. If you're a bad person and don't install your gems per user, you may need to throw a sudo in there.

Installing from source is a bit involved just because you need to generate the OpenGL bindings before using them. To do this, simply clone the repository and navigate to its root directory in a terminal. Once there, run gen_from_xml.rb:

$ ./gen_from_xml.rb

This will pull down the Khronos GL XML spec files and proceed to generate the appropriate OpenGL function bindings for the OpenGL core profile (3.2 and up, no deprecated functions). If you'd like to generate bindings for non-core functions, open gen_from_xml.rb in your text editor and change the GEN_GL3_AND_UP constant's value to false. Attempting to use functions that don't exist for a given context will result in errors, so keep that in mind.

Once the functions have been generated, you can proceed to build and install the gem as per usual:

$ gem build opengl-core.gemspec
$ gem install opengl-core-_._._.gem

Afterward, all GL enums and commands will be under the Gl module (note the lowercase L). Just require 'opengl-core' and you should be on your way. You don't have to statically link to the GL libraries, they will be loaded at runtime on first use.

In an effort to make working with OpenGL simpler in Ruby, an additional project, opengl-aux, was started using aux classes/functions previously included in opengl-core. opengl-aux provides Ruby-friendlier (still not necessarily friendliest) classes and functions to help people uncomfortable working with raw OpenGL bindings.

Your system's GL library and functions are loaded on a first-use basis, so the first time you call glClear, the function will be loaded. This may change in the future, but it's worth being aware of it. Later down the road I'll probably add a function to load all possible GL symbols.

Bear in mind, also, that the GL commands are currently all just providing more or less the same functionality they would in C or C++. This means that they do expect pointers and such. You can allocate these using Fiddle::Pointer.malloc and so on. However, in addition to this, each GL function is an alias of its raw function. So, in the module, you have both glClear and glClear__, the latter being the raw function and the former being a wrapper around it that can be overridden.

Have a patch to contribute? Just submit a pull request on GitHub and describe the contents of the patch as clearly as possible. Any contributions must be licensed under the same license as the rest of opengl-core.

opengl-core has received contributions and other help from the following people:

• Noel Cower
• Nogbit
• Justin Scott
• John Woods

For a complete overview of each contribution, you can clone the repository and use git shortlog.

The OpenGL bindings are licensed under a simplified BSD license. This is to keep things simple for the both of us, but if you need it simpler, just contact me and we'll work something out.

Copyright (c) 2013 - 2014, opengl-core project contributors.
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer. 
2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution. 

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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