pawn wip

diff --git a/pawn.scad b/pawn.scad
new file mode 100644 (file)
index 0000000..805c5f3
--- /dev/null
+++ b/pawn.scad
@@ -0,0 +1,57 @@
+// -*- C -*-
+
+// shape parameters
+
+r1 =  3;
+r2 =  6; a2 = 30;
+r3 = r2;
+r4 =  8; a4 = 30;
+r5 = 12;
+h6 =  5; a6 = 5;
+
+// coordinates
+
+                       z1 =  0;
+h2 = r2 * sin(a2);     z2 = z1 - h2;
+h3 = r3 * sin(a2);     z3 = z2 - h3;
+h4 = r4 * sin(a4);     z4 = z3 - h4;
+h5 = r5 * sin(a4-a6);  z5 = z4 - h5;
+                       z6 = z5 - h6;
+
+x1 =  0 - r1;
+x2 = x1 + r2 * (1-cos(a2));
+x3 = x2 + r3 * (1-cos(a2));
+x4 = x3 - r4 * (1-cos(a4));
+x5 = x4 - r5 * (1-cos(a4-a6));
+x6 = x5 - h6 * tan(a6);
+
+$fa=1;
+$fs=0.1;
+
+module ConvexSegment(xc, zc, r, zmin, zmax){
+  intersection(){
+    translate([xc,zc]) circle(r=r);
+    translate([-50,zmin-0.01]) square([55,zmax-zmin+0.02]);
+  }
+}
+
+module PawnTemplate(){
+  intersection(){
+    union(){
+      ConvexSegment(x1 + r1, z1, r1, z1, 50);
+      ConvexSegment(x1 + r2, z1, r2, z2, z1);
+      translate([x5 + r5 * cos(a6), z5]) circle(r=r5);
+      polygon([[x6,z6-1],
+              [x5,z5],
+              [1,z5],
+              [1,z6-1]]);
+      difference(){
+       translate([-50,z4]) square([52,z2-z4]);
+//     circle(
+      }
+    }
+    translate([-100,z6]) square([100.1, 200]);
+  }
+}
+
+PawnTemplate();