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can someone tell me why this always fails?
it isn't garenteed to always reach 63,63 even through i floor it.

 
function main()
	domain=true

	while domain do
	 cls()
		spr(16,4,0,15,2)

		for i=0,8 do star() end
		yield()

	end
end

function star()
 dostar=true
 inst  =
 {
  sx=rnd(127),
  sy=127,
  ex=63,
  ey=63,
 }

	while dostar do
		local dx=flr(inst.sx)==flr(inst.ex)
		local dy=flr(inst.sy)==flr(inst.ey)
		rectfill(0,0,127,24,0)
		print(tostr(dx)..","..tostr(dy),0,0,7)
		if dx and dy then	
			dostar=false
		else
		 pset (inst.sx,inst.sy,7)
		 print(flr(inst.sx).."/"..flr(inst.ex),0,8,7)
		 print(flr(inst.sy).."/"..flr(inst.ey),0,16,7)
			inst.sx+=(inst.ex-inst.sx)*mainstarspd
			inst.sy+=(inst.ey-inst.sy)*mainstarspd
		end
		yield()
	end
end



Try printing out these two values:

 
print((inst.ex-inst.sx)*mainstarspd)
print((inst.ey-inst.sy)*mainstarspd)

I suspect one of the values is small enough that the multiply underflows and the result is a 0 offset that keeps you from arriving at the end value.

Remember (or discover now) that PICO-8 uses signed 16.16-bit fixed point math. You only have 16 bits of fractional precision. If you were, for instance, to square any number less than than 1/256 (0x.01), you'd get 0.

@Felice i can't print it out without it flowing offscreen or clearing over the previus number.

it updates too fast.



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