After reading Prince’s explanation of the song: (via NME.com)
“When there’s blood in the sky – red and blue = purple … purple rain pertains to the end of the world and being with the one you love and letting your faith/god guide you through the purple rain.”
I decided to make a simple PurpleGenerator:
And have background drawn with an alpha setting of
40 (out of 255), to create a fading effect:
Click + Drag… generates the new rain drops that location.