Aliasing problems with postprocessing addons

[kaspar.wtf]

Hey, I’ve just started trying some post processing addons such as ofxBloom and ofxPostProcessing but every time I get some aliasing problems when using the addons. Here are two pictures to compare.

I’ve tried using different versions of openGL and get the same issue, does anybody know where this could come from ? thanks

[roymacdonald]

Hi, which filter are you applying in the images you share? It could be several different
things.

[edapx]

I do not know the addons you mentioned, but check the sample resolution of the FBO.

FXAA (or similar antialiasing) using GLSL 1.5 / GL 3+

hey @ivaylopg, i’m assuming you are using the ofGLProgrammableRenderer to get GLSL 1.50, but the solution I’m going to suggest should work independently of your renderer: render to a multi-sampled framebuffer (FBO), then draw the multi-sampled FBO to your screen. To activate Anti-Aliasing for an ofFbo you would allocate the ofFbo (let’s call it, say, myFbo) with numSamples set to 4, for example. That would give you 4xMSAA. Note that .numSamples is part of ofFbo::Settings, so get an ofFbo Settin…

This is some code that I have around in an old project

ofFbo::Settings settings;
// https://forum.openframeworks.cc/t/fxaa-or-similar-antialiasing-using-glsl-1-5-gl-3/16282/6
settings.numSamples = 4; // try 8 if your GPU supports it.
settings.useDepth = false; // set it to true if you are going to use meshes and need the depth, otherwise false is ok for raymarching
settings.width = ofGetWidth();
settings.height = ofGetHeight();
fbo.allocate(settings);

[edapx]

BTW, ofxPostProcessing it has a fxaa pass, have you tried it?

[kaspar.wtf]

aw its completely my bad, I thought I had tried different versions of GL but I hadn’t. It works fine with GL2 but not with GL3.2 the dev mentioned “Add support for ofGLProgrammableRenderer with version 150 shaders” in the todo list, I’m really sorry for wasting your time