SCN

SCN() allows you to execute code between the drawing of each scan line; for example, to manipulate the palette. This makes it theoretically possible to use a different palette for every scan line.

Parameters:

scanLine The next scan line to be drawn (0..135)

Usage:

function SCN(scanLine)
  -- your code here
end

Example:

The following example displays all 256 possible shades of gray. This can be done with any color.

-- title:  256 shades of gray
-- author: Marcuss2, fixed by nesbox
-- desc:   Showoff of grayscale
-- script: lua
-- input:  mouse

ADDR = 0x3FC0
palette = 0

function addLight()
 for i=0, 15 do
  for j=0, 2 do
   poke(ADDR+(i*3)+j, palette)
  end
  palette = palette + 1
 end	
end

function SCN(scnline)
 if scnline % 8 == 0 then
  addLight()
 end
end

function init()
 for i=0, 16 do
  rect(i*15, 0, 15, 240, i)
 end
end

init()

function TIC()
 palette = 0
end