clip

clip Unsets the clipping region (draws to the full screen)

clip(x, y, width, height) Sets the clipping region

Parameters

x, y : coordinates of the top left of the clipping region
width : width of the clipping region in pixels
height : height of the clipping region in pixels

Description

This function limits drawing to a clipping region or 'viewport' defined by x,y, width, and height. Any pixels falling outside of this area will not be drawn.

Calling clip() with no parameters will reset the drawing area to the entire screen.

Example

clip_demo

-- clip example
-- author: paul59
-- script: lua

t=0
x=96
y=24
local BLACK=0
local BLUE=13
local c=false

function TIC()

	if btn(0) then y=y-1 end
	if btn(1) then y=y+1 end
	if btn(2) then x=x-1 end
	if btn(3) then x=x+1 end
	cls(BLUE)

	if c then
		cls(BLACK)
		-- limit drawing to a 100 pixel wide/high
		-- region, with top left at 60,20
		clip(60,20,100,100)
		-- cls() is also affected by
		-- the clipping region
		cls(BLUE)
	else
		-- reset to entire screen
		clip()
	end

	spr(1+t%60//30*2,x,y,14,3,0,0,2,2)
	print("Press 'Up' To",76,84)
	print("Toggle Clipping",72,94)
	if btnp(0) then c=not c end

	t=t+1

end