refactor

examples/dragon/dragon_scales.scad

@@ -0,0 +1,66 @@
+use <shape_circle.scad>;
+use <shear.scad>;
+use <polyhedron_hull.scad>;
+use <ptf/ptf_rotate.scad>;
+use <experimental/convex_hull3.scad>;
+
+function one_body_scale(body_r, body_fn, scale_fn, scale_tilt_a) =  
+    let(
+	    scale_r = PI * body_r / body_fn,
+		double_scale_r = scale_r * 2,
+		shape_scale = shape_circle(scale_r, $fn = scale_fn),
+		scale_pts = concat(
+			[[0, 0, scale_r / 2 + body_r]], 
+			[
+				for(p = shape_scale) 
+					ptf_rotate([p[0], p[1] * 2.01, body_r], [scale_tilt_a, 0, 0])
+			], 
+			[for(p = shape_scale) [p[0], p[1] * 2.01, 0]]
+		)
+	)
+    convex_hull3(scale_pts);
+
+
+module dragon_body_scales(body_r, body_fn, one_scale_points_faces) {
+	double_scale_r = PI * body_r / body_fn * 2;
+
+	module ring_scales() {
+	    a_step = 360 / body_fn;
+		for(a = [0:body_fn - 1]) {
+			rotate([0, a * a_step, 0])
+			polyhedron(
+			     one_scale_points_faces[0], 
+				 one_scale_points_faces[1]
+		    );
+		}
+	}
+	
+	a = 180 / body_fn;
+	for(y = [0:1]) {
+		translate([0, y * double_scale_r])
+		rotate([0, (y % 2) * a])
+		    ring_scales();
+	}	
+}
+
+module tail_scales(ang, leng, radius, height, thickness) {
+    module one_scale() {
+        rotate([0, ang, 0]) 
+        shear(sx = [0, -1.5])
+        linear_extrude(thickness, center = true) 
+        scale([leng, 1]) 
+            circle(1);    
+    }
+
+    for(a = [0:30:330]) {
+        hull() {
+            rotate(a) 
+            translate([radius, 0, height]) 
+                one_scale();
+                
+            rotate(a + 15) 
+            translate([radius, 0, height + 1.75]) 
+                one_scale();
+        }
+    }
+}