[ ] g_central_glow (didn't we had this one before?! I checked, it's just missing as an option in gui_2.py, maybe it was not working properly?)
[ ] g_shooting_star: add option for size change (shrinking, growing) while flying through the cube
[ ] e_quadrant_cut: "cut" quadrants out (set brightness to 0), could be nice with g_central_glow or any other more blurred generators
[x] g_cube_edges: turn on random edges of a cube (could mix nicely with g_cube) or let a snake run along the cube edges
[x] maybe introduce a g_rain again?
[ ] global effects for channel mixing options: Not only sum the channels (Mix=A+B), maybe also remove B from A (Mix=A-B), since they have different colors, channel B changes the color of A, not only setting it to 0