2D particles

How to make 2D particle system? Looks like it is not possible right now?

I have a 3D game and want to add screen space 2D particle effects. Please do not tell me to create regular 3D particle system and then render it with orthogonal camera, this is not true 2D particles.

For example I want to have equal speed for all particles… Maybe I can use 3D system and prevent move particles in Z axis some way?

With a regular system, you could force the particles to emit on a plane by changing the shape they emit from - cubes and cones can be flattened and there are lots of velocity/speed settings to explore. The particles would be in 3D space, but in 2D relative to themselves. You could even render the particles with a separate camera on top of the regular 3D, so they’d be ‘always on top.’

You could use GUI calls in OnGUI, and essentially roll your own basic particle system like I used to do back in BASIC days. Ha. GUI.DrawTexture lets you draw textures on top of the regular rendering. It’s a little bit more time-consuming for the processor, but up to a point it won’t be noticeable.

Use cone shape and set angel to 90 of cone. Thats it!