INTRODUCTION

GFXL is my work on graphics. It contains some linear algebra classes and some GUI code which uses SDL. I intend to expand this work, making more useful libraries designed for real-time graphics programming and demos. My goal is a collection of modular libraries, but much of this work dovetails with working on a game engine.

This is all still experimental, so user beware. It is generally safe, but incomplete, and I have not yet switched over to an actual unit testing system. I do test for bugs, but you never know.

OVERVIEW

GFXL is an attempt to make a C++ friendly set of libraries that uses OpenGL and SDL under the hood to work with creating pretty pictures. While OpenGL and SDL already provide the raw functionality for that task, they are still a little clunky. They serve to smooth out the differences between systems, and OpenGL in particular is still very much concerned with nitpicky details that, while important, can distract from development and learning to program for graphics. Neither library is a point of entry for application code to start drawing things.

The first concern of GFXL is a core set of datatypes and utility classes. In order to provide a generic set of bindings, OpenGL thinks in terms of the lowest level abstractions possible and works like a verbose C. In contrast, GLSL speaks directly in the language of 3D graphics: linear algebra and multi-variate objects. GFXL implements a suite of types that provide syntactic support for these kinds of mathematical objects and deals with the details of mapping them to OpenGL and GLSL.

Component swizzling is among the most important functionality provided in terms of ease of use, and is implemented to resemble as close as possible a real feature of the language. The clarity swizzling provides in expressing vector and matrix algorithms is well worth the complexity. All primitive GLSL datatypes are represented in the code with the same names, designed to map to memory the way OpenGL and GLSL expect.

The utility classes implement safe and mindful ways of manipulating those mathematical objects. A suite of mathematical operators is provided which maintain accuracy and encapsulate the actual calculations to make optimization easier. GFXL also has its own type information system, used for debugging, testing, error reporting, and integration with how OpenGL handles memory.

Wherever possible, the datatypes and support classes shift error checking and catching firstly to preprocessing, then compilation, then runtime exceptions. C++ does not have bounds or type checking in certain compilation situations, and so some errors can only be caught at runtime (dimension mismatches for arbitrary arrays are an important instance of this).

The GUI related code is currently a wrapper for SDL 2.0 calls and structures. This will change, and it is not complete yet as I have not migrated the compilation settings from MinGW and Windows to GCC and Linux.