I'm trying to model a stream of water as particles (e.g. from a garden hose). The water is fairly turbulent with a lot of air bubbles - refraction is not likely to be an issue. What I'm trying to do is display the droplets as semitransparent with a blurred background - similar to Vista's glass effects. I'm using OpenGL and GLSL with a custom engine. If possible, I'd like to avoid doing a glReadPixels() call, as that would slow things down a lot. I'm thinking of maybe doing a two-pass render - render once (without the water) into a framebuffer object, make a texture off of that, and then use that texture to do the blurring on the GPU. Does this seem like a reasonable way of doing things? If so, I'm looking for implementation suggestions, and if not, what am I doing wrong?