With this shader you can create a feel of depth in space. You need to use a sprite sheet for this shader. Exact sprite picked by distance from camera, so that you can bind it to any value from graph editor.
1. Extract sprite sheets with any row, column count
2. Fog Color for far particles
3. Near camera smooth showing, so that particles don't cover whole screen
4. Debug sprite sheet, when texture not specified
For bokeh effect there is a tool for Photoshop.
Spark AR block assets