gficl

A common lisp library for simplifying the creation of opengl apps. This does not replace opengl functions, instead making things like framebuffer creation and vertex data loading easier and supplying linear algebra types and functions.

Check out the examples folder for a better idea.

Requirements

• A Common Lisp Implementation (tested with SBCL)
• Quicklisp (or any other way to load asdf systems and download nessecary libraries)
• The glfw C library - may be installed automatically by quicklisp

Building an Example

To check all the requirements are installed properly, run make. A portable executable version of one of the examples should be in bin/.

Using the Library

gficl-examples.asd shows you how you might use the library into your project.

Any opengl objects created by gficl inherit from GL-OBJECT and need to be manually freed after their resources are no longer needed. This is done by calling DELETE-GL on the object.

Any opengl objects crated by gficl with a resource that have an obvious way to be bound will have the function BIND-GL defined on them. (ie. shaders, textures, renderbuffers, framebuffers, vertex data...)

App Skeleton

The basic outline of an app using this library is a main loop that opens a window and updates and draws each frame.

(defun my-app ()
  (gficl:with-window
   (:title "My App" :width 500 :height 400 :resize-callback #'my-resize-fn)
   (my-setup-fn)
   (loop until (gficl:closed-p)
	 do (my-update-fn)
	 do (my-draw-fn))
   (my-cleanup-fn)))

where my-setup-fn and my-cleanup-fn would create and destroy any top level opengl resources you might need, such as shaders, framebuffers, vertex data, textures, etc.

my-resize-fn takes a width and height, and is called any time the window is resized. This can be used for recreating the framebuffers to match the screen size, or updating the projection matrix.