diff --git a/collisiontest.p8 b/collisiontest.p8
index 0a619ca..8bdbc26 100644
--- a/collisiontest.p8
+++ b/collisiontest.p8
@@ -114,7 +114,8 @@ end
 function _draw()
  cls(0)
 	rect(bx0,by0,bx1,by1,6)
-	line(lx0,ly0,lx1,ly1,2)
+	zot(lx1,ly1,5,lx1-lx0,ly1-ly0,10,9,8)
+	--line(lx0,ly0,lx1,ly1,2)
 	local cmin, cmax = collides()
 	if cmin then
 	 local dx,dy=lx1-lx0,ly1-ly0
@@ -122,7 +123,7 @@ function _draw()
 	      ly0 + dy*cmin,
 	      lx0 + dx*cmax,
 	      ly0 + dy*cmax,
-	      8)
+	      11)
 	 pset(lx0 + dx*cmin,
 	      ly0 + dy*cmin,
 	      12)
@@ -130,6 +131,29 @@ function _draw()
 	
 	pset(last_mx,last_my,7)
 end
+-->8
+function zot_one(x, y, r, ir, dx, dy, hot, warm)
+ local x0, y0 = x-dx, y-dy
+ local rx,ry,irx,iry=r*sgn(dx),r*sgn(dy),ir*sgn(dx),ir*sgn(dy)
+ if warm then
+  line(x0+irx,y0-ry,x+rx,y-iry,warm)
+  line(x0-rx,y0+iry,x-irx,y+ry,warm)
+  --line(x0-rx,y0-ry,x+rx,y+ry,warm)
+ end
+ line(x0,y0,x-rx,y-iry,hot)
+ line(x0,y0,x+irx,y-ry,hot)
+ --line(x0,y0,x+rx,y+ry,hot)
+end
+
+function zot(x,y,r,dx,dy,hot,warm,cold)
+ local x0,y0=x-dx,y-dy
+ if (cold) rectfill(x0-r,y0-r,x0+r,y0+r,cold)
+ for ir=-r,0 do
+  zot_one(x,y,r,ir,dx,dy,hot,warm)
+  zot_one(x,y,r,-ir,dx,dy,hot,warm)
+ end
+ rectfill(x-r,y-r,x+r,y+r,hot)
+end
 __gfx__
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