P3 RGB pixel panel

Great! Just committed:

>g=Graphics.createArrayBuffer(64,32,4,{interleavex:true})
=Graphics: { 
  buffer: new ArrayBuffer(1024)
 }
>g.setPixel(0,0,7);print(g.buffer) 
new Uint8Array([7, 0, 0, 0, 0, 0, ....
=undefined
>g.setPixel(0,16,7);print(g.buffer) 
new Uint8Array([119, 0, 0, 0, 0,....

Hopefully that'll work for you - and who knows, maybe it'll end up being useful for something else later on :)