PSPE - GE progress

December 20th, 2012, 00:47 Posted By: wraggster

Hlide here

Oh god, even nvidia opengl 4.x may be so picky when dealing with their new extensions. How many times i was puzzled by a black screen because of a lack of clear documentation about how to use such features.

About transform-feedback: i finally get a working version but i decided to put it aside for two reasons. First, it is not clear it is the fastest way to decode vertices because there are some overheads about setting it. Second, you can easily waste time to find a bug if you change something in the shader. So i wrote a software version of vertex decoder using c++ template. It's probably the fastest decoder amongst the existing ones but also the fatest as it generates a very big binary and makes compilation time a nightmare. Transform-feedback version may be back as an alternative but not so soon.

I started to write the renderer part using two extensions only available from OpenGL 4.x. One was quite picky until i finally understand how it must be correctly used. The goal is to have all the GE pixel operations done in the same way through the fragment shader, including: texture mapping, color doubling, color addition, fogging, scissoring, depth range test, color test, alpha test, stencil test, depth test, blending, dithering, color clamping, logical operations, color and alpha masking. You cannot do all those through the usual opengl pixel operations.

Honestly, i never expected for OpenGL to be so fastidious to code that I may be discouraged a great number of times because you can easily break something you thought acquired without knowing why.

http://www.pspe4all.com/news.php

There are 0 comments - Join In and Discuss Here