elli - nesbox/TIC-80 GitHub Wiki

This was added to the API in version 0.90.

elli(x, y, a, b, color)

Parameters

• x, y : the coordinates of the ellipse's center
• a : the horizontal radius of the ellipse in pixels
• b : the vertical radius of the ellipse in pixels
• color: the index of the desired color in the current palette

Description

This function draws a filled ellipse centered at x, y using palette index color and radii a and b. It uses the Bresenham algorithm.

See also:

• ellib - draw only the boundary of the ellipse

Example

-- title:  ellipse example
-- author: paul59
-- script: lua

local CX,CY=120,68
local RED,GREEN=2,6
local MIN,MAX=8,48

local hrad,vrad=16,16

function TIC()

	if btn(0) and vrad<MAX then vrad=vrad+1 end
	if btn(1) and vrad>MIN then vrad=vrad-1 end
	if btn(2) and hrad<MAX then hrad=hrad+1 end
	if btn(3) and hrad>MIN then hrad=hrad-1 end

	cls(0)
	print('Use the cursor keys to adjust size',24,2,13)
	--draw filled ellipse
	elli(CX,CY,hrad,vrad,RED)
	--draw outline ellipse
	--swap the horizontal and vertical radii
	ellib(CX,CY,vrad,hrad,GREEN)
end