add twisted_maze

examples/twisted_maze.scad

@@ -0,0 +1,65 @@
+include <hull_polyline3d.scad>;
+include <rotate_p.scad>;
+include <square_maze.scad>;
+
+rows = 8;
+columns = 16;
+block_width = 2;
+wall_thickness = 1;   
+angle = 90;
+// $fn = 24;
+
+function block_walls(block, block_width) = 
+    let(
+        loc = [get_x(block) - 1, get_y(block) - 1] * block_width,
+        wall_type = get_wall_type(block),
+        upper_wall = wall_type == UPPER_WALL || wall_type == UPPER_RIGHT_WALL ? [[0, block_width] + loc, [block_width, block_width] + loc] : [],
+        right_wall = wall_type == RIGHT_WALL || wall_type == UPPER_RIGHT_WALL ? [[block_width, block_width] + loc, [block_width, 0] + loc] : []
+    )
+    concat(
+        upper_wall, 
+        right_wall
+    ); 
+  
+function maze_walls(blocks, rows, columns, block_width, left_border = true, bottom_border = true) = 
+    let(
+        left_walls = left_border ? [for(y = [0:rows - 1]) [[0, block_width * (y + 1)], [0, block_width * y]]] : [],
+        buttom_walls = bottom_border ? [for(x = [0:columns - 1]) [[block_width * x, 0], [block_width * (x + 1), 0]]] : []
+    )
+     concat(
+        [
+            for(block = blocks) 
+            let(pts = block_walls(block, block_width))
+            if(pts != []) pts
+        ]
+        , left_walls, buttom_walls
+    );
+    
+function x_twist(walls, angle, rows, columns, block_width) = 
+    let(
+        y_offset = rows * block_width / 2,
+        y_centered = [
+            for(wall_pts = walls) 
+                [for(pt = wall_pts) [pt[0], pt[1], 0] + [0, -y_offset, 0]]
+        ],
+        a_step = angle / columns
+    )
+    [
+        for(wall_pts = y_centered)    
+           [
+               for(pt = wall_pts)
+                   rotate_p(pt, [pt[0] * a_step, 0, 0]) + [0, y_offset, 0]
+           ]
+    ];
+
+blocks = go_maze( 
+    1, 1,   // starting point
+    starting_maze(rows, columns),  
+    rows, columns
+);
+    
+walls = maze_walls(blocks, rows, columns, block_width);
+
+for(wall_pts = x_twist(walls, angle, rows, columns, block_width)) {   
+   hull_polyline3d(wall_pts, wall_thickness);
+}