From 4708f039fcff5ec72f1b7d0a9f26dbacc8f97a98 Mon Sep 17 00:00:00 2001
From: Justin Lin <caterpillar@openhome.cc>
Date: Sun, 1 Sep 2019 11:58:44 +0800
Subject: [PATCH] hex_maze_stereographic_projection

---
 .../hex_maze_stereographic_projection.scad    | 173 ++++++++++++++++++
 1 file changed, 173 insertions(+)
 create mode 100644 examples/hex_maze_stereographic_projection.scad

diff --git a/examples/hex_maze_stereographic_projection.scad b/examples/hex_maze_stereographic_projection.scad
new file mode 100644
index 00000000..811c5e58
--- /dev/null
+++ b/examples/hex_maze_stereographic_projection.scad
@@ -0,0 +1,173 @@
+include <line2d.scad>;
+include <polyline2d.scad>;
+include <stereographic_extrude.scad>;
+include <maze.scad>;
+
+x_cells = 5;
+cell_radius = 20;
+wall_thickness = 12;
+fn = 24;
+shadow = "YES"; // [YES, NO]
+wall_height = 1;
+
+// create a maze
+module hex_maze(y_cells, x_cells, maze_vector, cell_radius, wall_thickness) {
+
+	// style : upper/rights/right
+	module cell(x_cell, y_cell, style) {
+		module upper_wall() {
+			polyline2d(
+				[for(a = [240:60:300]) 
+					[cell_radius * cos(a), cell_radius * sin(a)]], 
+				wall_thickness,
+                startingStyle = "CAP_ROUND", endingStyle = "CAP_ROUND"
+			);
+		}
+		
+		module down_wall() {
+			polyline2d(
+				[for(a = [60:60:120]) 
+					[cell_radius * cos(a), cell_radius * sin(a)]], 
+				wall_thickness,
+                startingStyle = "CAP_ROUND", endingStyle = "CAP_ROUND"
+			);
+		}
+		
+		module up_left_wall() {
+			polyline2d( 
+				[for(a = [180:60:270]) 
+					[cell_radius * cos(a), cell_radius * sin(a)]], 
+				wall_thickness,
+                startingStyle = "CAP_ROUND", endingStyle = "CAP_ROUND"
+			);  
+		}
+		
+		module down_left_wall() {
+			polyline2d( 
+				[for(a = [120:60:180]) 
+					[cell_radius * cos(a), cell_radius * sin(a)]], 
+				wall_thickness,
+                startingStyle = "CAP_ROUND", endingStyle = "CAP_ROUND"
+			);  	
+		}
+		
+		module up_right_wall() {
+			polyline2d( 
+				[for(a = [300:60:360]) 
+					[cell_radius * cos(a), cell_radius * sin(a)]], 
+				wall_thickness,
+                startingStyle = "CAP_ROUND", endingStyle = "CAP_ROUND"
+			);  
+		}
+		
+		module down_right_wall() {
+			polyline2d(
+				[for(a = [0:60:60]) 
+					[cell_radius * cos(a), cell_radius * sin(a)]], 
+				wall_thickness,
+                startingStyle = "CAP_ROUND", endingStyle = "CAP_ROUND"
+			); 
+		}
+		
+		module right_walls() {
+			up_right_wall();
+			down_right_wall();
+		}
+		
+		module cell_border_wall() {
+			if(y_cell == 0 && x_cell % 2 == 0) {
+				if(x_cell != 0) {
+					up_left_wall();
+				}
+				up_right_wall();
+			}
+			
+			if(x_cell == 0) {
+				up_left_wall();
+				down_left_wall();
+			}
+			
+			if(y_cell == (y_cells - 1)) {
+				down_wall();
+				if(x_cell % 2 != 0) {
+				    down_left_wall();
+				}
+			}		
+		}
+		
+		module cell_inner_wall() {
+			if(style == "upper") {
+				upper_wall();
+			} else if(style == "rights") {
+				right_walls();
+			} else if(style == "right") {
+				if(x_cell % 2 == 0) {
+					up_right_wall();
+				} else {
+					down_right_wall();
+				}
+			}
+		}
+		
+		module cell_wall() {
+			cell_inner_wall();
+			cell_border_wall();
+		}
+
+		grid_h = 2 * cell_radius * sin(60);
+		grid_w = cell_radius + cell_radius * cos(60);
+
+		translate([grid_w * x_cell, grid_h * y_cell + (x_cell % 2 == 0 ? 0 : grid_h / 2), 0]) 
+			cell_wall();
+	}
+	
+	// create the wall of maze
+
+	for(i = [0:len(maze_vector) - 1]) {
+		cord = maze_vector[i];
+		x = (cord[0] - 1) ;
+		y = (cord[1] - 1);
+		v = cord[3];
+		
+		if(v == 1 || v == 3) {
+			cell(x, y, "upper");
+			 
+		}
+		if(v == 2 || v == 3) {
+			cell(x, y, "rights");
+		}  
+		if(v == 0 || v == 1) {
+			cell(x, y, "right"); 
+		}
+	}  
+}
+
+module hex_maze_stereographic_projection(x_cells, cell_radius, wall_thickness, fn, wall_height, shadow) {
+    y_cells = round(0.866 * x_cells - 0.211);
+
+    grid_h = 2 * cell_radius * sin(60);
+    grid_w = cell_radius + cell_radius * cos(60);	
+    
+    square_w = grid_w * (x_cells - 1) + cell_radius * 2 + wall_thickness * 2;
+    square_h = grid_h * y_cells + grid_h / 2 + wall_thickness * 2;
+    square_offset_x = square_w / 2 -cell_radius - wall_thickness;
+    square_offset_y = square_h / 2 -grid_h / 2 - wall_thickness;
+    
+    pyramid_height = square_w / sqrt(2);
+  
+    // create a maze     
+    maze_vector = go_maze(1, 1, y_cells, x_cells, init_maze(y_cells, x_cells));
+
+    stereographic_extrude(square_w, $fn = fn) 
+	    translate([grid_w - square_w / 2, grid_h - square_w / 2, 0]) 
+		    hex_maze(y_cells, x_cells, maze_vector, cell_radius, wall_thickness);
+
+	if(shadow == "YES") {
+		color("black") linear_extrude(wall_height) 
+		    translate([grid_w - square_w / 2, grid_h - square_w / 2, 0]) 
+			    hex_maze(y_cells, x_cells, maze_vector, cell_radius, wall_thickness);
+    }
+        
+}
+
+hex_maze_stereographic_projection(x_cells, cell_radius, wall_thickness, fn, wall_height, shadow);
\ No newline at end of file