Round poly now perfectly fits radius

round_polygon.scad

@@ -14,7 +14,7 @@ oct = [
     [corn,-corn]
 ];
 
-function scale_xy(xy, m) = let(nz_xy = sign(xy == 0 ? 1 : xy) * max(abs(xy), 0.0000001)) [ for (i = m) [i.x * nz_xy, i.y * nz_xy]];
+function scale_xy(shape, xy, allow_zero = false) = let(s = allow_zero ? xy : sign(xy == 0 ? 1 : xy) * max(abs(xy), 0.0001)) [ for (i = shape) [i.x * s, i.y * s]];
 
 function normalize(vec) = vec / norm(vec);
 
@@ -28,14 +28,13 @@ module round_poly(shape, radius, sharpness = 0){
     corner_r = lerp(radius, 0, sharpness);
     corner_offset = lerp(0, radius, sharpness);
     
-    
     minkowski(){
-        polygon(add_radius(scale_xy(0, shape),corner_offset));
+        polygon(add_radius(scale_xy(shape,0),corner_offset));
         circle(max(corner_r, 0.0001));
     }
 }
 
 
-radius = 3;
+radius = 1;
 
 round_poly(oct,radius, $t);