TIC-80/Lua rotated filled ellipse

snippet.lua

// d1,d2: ellipse width/height
// r: rotation
function ellipf(x,y,d1,d2,r)
	-- i is the angle step. We increment this until we've passed 2*PI
	i=0.2
	
	for a=0,6.29+i,i do
		x1,y1=rotate(x,y,d1,d2,r,a)
		x2,y2=rotate(x,y,d1,d2,r,a+i)
		tri(x,y,x1,y1,x2,y2,2)
	end
end

function rotate(x,y,dx,dy,r,a)
	dx=math.cos(a)*dx
	dy=math.sin(a)*dy
 
	return
		x+dx*math.cos(r)-dy*math.sin(r),
		y+dx*math.sin(r)+dy*math.cos(r)
end