Blending pixelation

I’m playing around with making lots of particles. Here, I’m trying to achieve a fire effect through particle blending (possibly not the best way to go about doing it, but I’m a newbie :P) but along the areas where the particles are changing color there is horrible pixelation. I’m using source blending GL_SRC_ALPHA and destination blending GL_ONE. I’ve sorted and drawn the particles from back to front relative to the viewpoint and depth writing is off. I thought this might be poor blending on the part of my video card, but I’ve played openGL games and I’ve never noticed such horrible pixelation. Any way to get rid of this?

It looks like you might be using an 8-bit visual instead of a 24-bit visual. If you only have 8-bit color, you can see dithering like that.

try with glEnable(GL_POINT_SMOOTH)