ParaJVE : Parabellum's Java Vectrex Emulator   

Official Home of ParaJVE ... A travel through the programming of a freeware Vectrex emulator in java!

Tuesday, September 22, 2009  

Funny Bug

Just a quick post to show some odd ParaJVE rendering I've got last evening, due to combined bugs...

I was coding a kind of generator for the emulator, so that its GLSL shaders get automatically generated/compiled whenever some significant parameter is dynamically changed (such as the window size, or the filter kernel size and/or values).

The generated shaders obviously had a bug in the coordinates computation (that made the texture lookup fetch texels too far along the X axis).
This bug alone had nothing uncommon... until for some reason I forgot to clear the content of the back-buffer before each rendering loop. This then gave this strange feedback effect that I'd like to share :

It's even more amusing when you see it moving in real-time. But I guess you'll never see it alive, since I'm about to eradicate those nasty bugs... ;o) 

Labels: ,