From 42650a7a1933ce056b9f850a24b606d24799d764 Mon Sep 17 00:00:00 2001
From: Justin Lin <caterpillar@openhome.cc>
Date: Tue, 3 Mar 2020 09:01:19 +0800
Subject: [PATCH] refactor

---
 src/function_grapher.scad | 92 ++++++++++++++++++++++-----------------
 1 file changed, 51 insertions(+), 41 deletions(-)

diff --git a/src/function_grapher.scad b/src/function_grapher.scad
index 7bd793fd..252336dd 100644
--- a/src/function_grapher.scad
+++ b/src/function_grapher.scad
@@ -162,52 +162,52 @@ module function_grapher(points, thickness, style = "FACES", slicing = "SLASH") {
         test_function_grapher_faces(pts, face_idxs);
     }
 
-    module tri_to_lines(tri1, tri2) {
-       polyline3d(concat(tri1, [tri1[0]]), thickness);
+    module tri_to_slash_lines(tri1, tri2) {
+        polyline3d(concat(tri1, [tri1[0]]), thickness);
+        if(tri2[0][0] == points[0][0][0]) {
+            polyline3d([tri2[0], tri2[2]], thickness);
+        }
 
-       if(slicing == "SLASH") {
-            if(tri2[0][0] == points[0][0][0]) {
-                polyline3d([tri2[0], tri2[2]], thickness);
-            }
-
-            if(tri2[1][1] == points[rows - 1][0][1]) {
-                polyline3d([tri2[1], tri2[2]], thickness);
-            }
-       }
-       else {
-            if(tri2[1][0] == points[0][columns - 1][0]) {
-                polyline3d([tri2[1], tri2[2]], thickness);
-            }
-
-            if(tri2[2][1] == points[rows - 1][columns - 1][1]) {
-                polyline3d([tri2[0], tri2[2]], thickness);
-            }
-       }
+        if(tri2[1][1] == points[rows - 1][0][1]) {
+            polyline3d([tri2[1], tri2[2]], thickness);
+        }
     }
 
-    module tri_to_hull_lines(tri1, tri2) {
+    module tri_to_backslash_lines(tri1, tri2) {
+        polyline3d(concat(tri1, [tri1[0]]), thickness);
+        if(tri2[1][0] == points[0][columns - 1][0]) {
+            polyline3d([tri2[1], tri2[2]], thickness);
+        }
+
+        if(tri2[2][1] == points[rows - 1][columns - 1][1]) {
+            polyline3d([tri2[0], tri2[2]], thickness);
+        }
+    }
+
+    module tri_to_slash_hull_lines(tri1, tri2) {
         hull_polyline3d(concat(tri1, [tri1[0]]), thickness);
 
-        if(slicing == "SLASH") {
-            if(tri2[0][0] == points[0][0][0]) {
-                hull_polyline3d([tri2[0], tri2[2]], thickness);
-            }
+        if(tri2[0][0] == points[0][0][0]) {
+            hull_polyline3d([tri2[0], tri2[2]], thickness);
+        }
 
-            if(tri2[1][1] == points[rows - 1][0][1]) {
-                hull_polyline3d([tri2[1], tri2[2]], thickness);
-            }
-       }
-       else {
-            if(tri2[1][0] == points[0][columns - 1][0]) {
-                hull_polyline3d([tri2[1], tri2[2]], thickness);
-            }
+        if(tri2[1][1] == points[rows - 1][0][1]) {
+            hull_polyline3d([tri2[1], tri2[2]], thickness);
+        }
+    }  
+
+    module tri_to_backslash_hull_lines(tri1, tri2) {
+        hull_polyline3d(concat(tri1, [tri1[0]]), thickness);
+
+        if(tri2[1][0] == points[0][columns - 1][0]) {
+            hull_polyline3d([tri2[1], tri2[2]], thickness);
+        }
+
+        if(tri2[2][1] == points[rows - 1][columns - 1][1]) {
+            hull_polyline3d([tri2[0], tri2[2]], thickness);
+        }
+    }        
 
-            if(tri2[2][1] == points[rows - 1][columns - 1][1]) {
-                hull_polyline3d([tri2[0], tri2[2]], thickness);
-            }
-       }
-    }    
-    
     module hull_pts(tri) {
        half_thickness = thickness / 2;
        hull() {
@@ -224,11 +224,21 @@ module function_grapher(points, thickness, style = "FACES", slicing = "SLASH") {
 
     module tri_to_graph(tri1, tri2) {
         if(style == "LINES") {
-            tri_to_lines(tri1, tri2);
+            if(slicing == "SLASH") {
+                tri_to_slash_lines(tri1, tri2);
+            }
+            else {
+                tri_to_backslash_lines(tri1, tri2);
+            }
         } else if(style == "HULL_FACES") {  // Warning: May be very slow!!
             tri_to_hull_faces(tri1, tri2);
         } else if(style == "HULL_LINES") {  // Warning: very very slow!!
-            tri_to_hull_lines(tri1, tri2);
+            if(slicing == "SLASH") {
+                tri_to_slash_hull_lines(tri1, tri2);
+            }
+            else {
+                tri_to_backslash_hull_lines(tri1, tri2);
+            }
         }
     }