GL_POINTS在粒子模拟中相互模糊

Question

I have a fire simulation, containing a large number of textured GL_POINTS . Each particle has a transparent background, and when facing the fire from certain angles, the blending works correctly. However, viewing it from other angles shows the backgrounds, which should be transparent, obscuring particles rendered behind others. See picture below.

As you can see, there appears to be a lot of black boxes in the way of the particle. How can I avoid this? The blend function I am using is GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA . Using GL_ONE as the second argument to glBlendFunc gives very similar results.

Answer 1

http://www.opengl-tutorial.org/intermediate-tutorials/billboards-particles/particles-instancing/#The_main_simulation_loop

There you can find the exact same problem and its solution. You indeed have to sort the particles as Gigo suggested. The reason is that alpha blending only looks right if the colors are mixed from back to front.

You can, however avoid sorting if you really want to. There are algorithms for 3d transparency that are a bit more efficient. See: http://www.opengl-tutorial.org/intermediate-tutorials/tutorial-10-transparency/#Order_Independent_Transparency