diff --git a/examples/maze/cube_maze.scad b/examples/maze/cube_maze.scad
index 8212f4db..462ec430 100644
--- a/examples/maze/cube_maze.scad
+++ b/examples/maze/cube_maze.scad
@@ -21,7 +21,7 @@ module cube_maze(maze_rows, block_width, wall_thickness, inner_cube, travel_all)
         module one_maze() {
             translate([origin, origin, half_cube_size]) 
             linear_extrude(wall_thickness) 
-                square_maze([1, 1], maze_rows, block_width, wall_thickness);
+                square_maze(maze_rows, block_width, wall_thickness);
         }
 
         one_maze();  
diff --git a/examples/maze/heart_maze.scad b/examples/maze/heart_maze.scad
index a6fa74c5..8d82c95b 100644
--- a/examples/maze/heart_maze.scad
+++ b/examples/maze/heart_maze.scad
@@ -60,9 +60,9 @@ module heart_to_heart_wall(radius, length, angle, thickness) {
 
 module heart_maze(maze, radius, cblocks, levels, thickness = 1) {    
 	function no_wall(block) = get_wall_type(block) == "NO_WALL";
-	function upper_wall(block) = get_wall_type(block) == "UPPER_WALL";
+	function top_wall(block) = get_wall_type(block) == "TOP_WALL";
 	function right_wall(block) = get_wall_type(block) == "RIGHT_WALL";
-	function upper_right_wall(block) = get_wall_type(block) == "UPPER_RIGHT_WALL";
+	function top_right_wall(block) = get_wall_type(block) == "TOP_RIGHT_WALL";
 
 	function get_x(block) = mz_square_get(block, "x"); 
 	function get_y(block) = mz_square_get(block, "y");
@@ -80,12 +80,12 @@ module heart_maze(maze, radius, cblocks, levels, thickness = 1) {
 		  
 			for(i = [0:len(maze) - 1]) { 
 				block = maze[i];
-				cr = get_x(block); 
-				cc = get_y(block) - 1;    
+				cr = get_x(block) + 1; 
+				cc = get_y(block);    
 				
 				angle = cc * arc_angle;
 				 
-				if(upper_wall(block) || upper_right_wall(block)) { 
+				if(top_wall(block) || top_right_wall(block)) { 
 				    heart_to_heart_wall(r * cr, r, cc * arc_angle , thickness);
 				} 
 			}
@@ -95,10 +95,10 @@ module heart_maze(maze, radius, cblocks, levels, thickness = 1) {
 	        // road to the next level
 			for(i = [0:len(maze) - 1]) { 
 				block = maze[i];
-				cr = get_x(block); 
-				cc = get_y(block) - 1;   
+				cr = get_x(block) + 1; 
+				cc = get_y(block);   
 				
-				if(no_wall(block) || upper_wall(block)) { 
+				if(no_wall(block) || top_wall(block)) { 
 				    ring_heart_sector(r * (cr + 1), (cc + 0.5) * arc_angle , thickness, thickness * 0.75);
 				}  
 			}
diff --git a/examples/maze/maze_masking.scad b/examples/maze/maze_masking.scad
index d8d3efe0..04a4e45a 100644
--- a/examples/maze/maze_masking.scad
+++ b/examples/maze/maze_masking.scad
@@ -3,7 +3,7 @@ use <maze/mz_square_walls.scad>;
 use <maze/mz_square_initialize.scad>;
 use <voxel/vx_contour.scad>;
 
-start = [2, 2];
+start = [1, 1];
 mask = [
 	[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
 	[0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0],
diff --git a/examples/maze/pyramid_maze.scad b/examples/maze/pyramid_maze.scad
index dcf24584..76dc023e 100644
--- a/examples/maze/pyramid_maze.scad
+++ b/examples/maze/pyramid_maze.scad
@@ -17,7 +17,7 @@ module pyramid_maze(maze_rows, block_width, wall_thickness) {
     intersection() {
         linear_extrude(leng * 2) 
         translate([-half_leng, -half_leng]) 
-            square_maze([1, 1], maze_rows, block_width, wall_thickness);
+            square_maze(maze_rows, block_width, wall_thickness);
 
         pyramid(leng + wall_thickness);
     }
diff --git a/examples/maze/random_scala.scad b/examples/maze/random_scala.scad
index 3508361c..95322251 100644
--- a/examples/maze/random_scala.scad
+++ b/examples/maze/random_scala.scad
@@ -21,7 +21,7 @@ module random_scala(rows, columns, start, width, height) {
 random_scala(
     rows = 2, 
     columns = 3,
-    start = [1, 1],
+    start = [0, 0],
     width = .5,
     height = .25
 );
\ No newline at end of file
diff --git a/examples/maze/regular_polygon_maze.scad b/examples/maze/regular_polygon_maze.scad
index 27a98fa6..9fe2bf47 100644
--- a/examples/maze/regular_polygon_maze.scad
+++ b/examples/maze/regular_polygon_maze.scad
@@ -26,7 +26,7 @@ module ring_regular_polygon_sector(radius, angle, thickness, width, sides) {
 }
 
 module regular_polygon_to_polygon_wall(radius, length, angle, thickness, sides) {
-    intersection() {
+   intersection() {
         difference() {
 		    circle(radius + length, $fn = sides);
 			circle(radius, $fn = sides);
@@ -38,9 +38,9 @@ module regular_polygon_to_polygon_wall(radius, length, angle, thickness, sides)
 
 module regular_polygon_maze(radius, cblocks, levels, thickness = 1, sides) {    
 	function no_wall(block) = get_wall_type(block) == "NO_WALL";
-	function upper_wall(block) = get_wall_type(block) == "UPPER_WALL";
+	function top_wall(block) = get_wall_type(block) == "TOP_WALL";
 	function right_wall(block) = get_wall_type(block) == "RIGHT_WALL";
-	function upper_right_wall(block) = get_wall_type(block) == "UPPER_RIGHT_WALL";
+	function top_right_wall(block) = get_wall_type(block) == "TOP_RIGHT_WALL";
 
 	function get_x(block) = mz_square_get(block, "x"); 
 	function get_y(block) = mz_square_get(block, "y");
@@ -62,12 +62,12 @@ module regular_polygon_maze(radius, cblocks, levels, thickness = 1, sides) {
 		  
 			for(i = [0:len(maze) - 1]) { 
 				block = maze[i];
-				cr = get_x(block); 
-				cc = get_y(block) - 1;    
+				cr = get_x(block) + 1; 
+				cc = get_y(block);    
 				
 				angle = cc * arc_angle;
 				 
-				if(upper_wall(block) || upper_right_wall(block)) { 
+				if(top_wall(block) || top_right_wall(block)) { 
 				    regular_polygon_to_polygon_wall(r * cr, r, cc * arc_angle , thickness, sides);
 				} 
 			}
@@ -80,10 +80,10 @@ module regular_polygon_maze(radius, cblocks, levels, thickness = 1, sides) {
 	        // road to the next level
 			for(i = [0:len(maze) - 1]) { 
 				block = maze[i];
-				cr = get_x(block); 
-				cc = get_y(block) - 1;   
+				cr = get_x(block) + 1; 
+				cc = get_y(block);   
 				
-				if(no_wall(block) || upper_wall(block)) { 
+				if(no_wall(block) || top_wall(block)) { 
 				    ring_regular_polygon_sector(r * (cr + 1), (cc + 0.5) * arc_angle , thickness, thickness * 0.75 , sides);
 				}  
 			}
diff --git a/examples/maze/senbon_torii.scad b/examples/maze/senbon_torii.scad
index a40d54a3..151460d1 100644
--- a/examples/maze/senbon_torii.scad
+++ b/examples/maze/senbon_torii.scad
@@ -2,7 +2,7 @@ use <maze/mz_hamiltonian.scad>;
 
 rows = 2;
 columns = 2;
-start = [1, 1];
+start = [0, 0];
 width = .5;
 height = .05;
 test_torii = "FALSE"; // [TRUE, FALSE]
diff --git a/examples/maze/step_pyramid_maze.scad b/examples/maze/step_pyramid_maze.scad
index 0947fb50..36eb72a6 100644
--- a/examples/maze/step_pyramid_maze.scad
+++ b/examples/maze/step_pyramid_maze.scad
@@ -40,7 +40,7 @@ module step_pyramid_maze(maze_rows, block_width, stairs_width) {
             
             translate([-(maze_rows * block_width) / 2, -(maze_rows * block_width) / 2, 0]) 
             difference() {
-                square_maze([1, 1], maze_rows, block_width, stairs_width);
+                square_maze(maze_rows, block_width, stairs_width);
 
                 // entry
                 translate([0, stairs_width]) 
diff --git a/examples/maze/stereographic_square_maze.scad b/examples/maze/stereographic_square_maze.scad
index a6d316dc..b69a7c7c 100644
--- a/examples/maze/stereographic_square_maze.scad
+++ b/examples/maze/stereographic_square_maze.scad
@@ -13,7 +13,7 @@ module stereographic_projection_maze2(maze_rows, block_width, wall_thickness, fn
     
     module maze() {
         translate([-block_width * maze_rows / 2, -block_width * maze_rows / 2, 0]) 
-            square_maze([1, 1], maze_rows, block_width, wall_thickness);
+            square_maze(maze_rows, block_width, wall_thickness);
     }
     
     stereographic_extrude(shadow_side_leng = length, $fn = fn)
diff --git a/src/maze/_impl/_mz_blocks_impl.scad b/src/maze/_impl/_mz_blocks_impl.scad
index 33832467..f3fd5057 100644
--- a/src/maze/_impl/_mz_blocks_impl.scad
+++ b/src/maze/_impl/_mz_blocks_impl.scad
@@ -2,7 +2,7 @@ use <_mz_comm.scad>;
 
 // find out the index of a block with the position (x, y)
 function indexOf(x, y, maze, i = 0) =
-    i > len(maze) ? -1 : (
+    i == len(maze) ? -1 : (
         [get_x(maze[i]), get_y(maze[i])] == [x, y] ? i : 
             indexOf(x, y, maze, i + 1)
     );
@@ -12,8 +12,8 @@ function visited(x, y, maze) = maze[indexOf(x, y, maze)][3];
 
 // is (x, y) visitable?
 function visitable(x, y, maze, rows, columns) = 
-    y > 0 && y <= rows &&     // y bound
-    x > 0 && x <= columns &&  // x bound
+    y >= 0 && y < rows &&     // y bound
+    x >= 0 && x < columns &&  // x bound
     !visited(x, y, maze);     // unvisited
 
 // setting (x, y) as being visited
@@ -58,23 +58,13 @@ function rand_dirs(c, seed) =
 _next_x_table = [1, 0, -1, 0];
 function next_x(x, dir, columns, wrapping) = 
     let(nx = x + _next_x_table[dir])
-    wrapping ? 
-        nx < 1 ? nx + columns : (
-            nx > columns ? nx % columns : nx
-        )
-        :
-        nx;
+    wrapping ? (nx < 0 ? nx + columns : nx % columns) : nx;
     
 // get y value by dir
 _next_y_table = [0, 1, 0, -1];
 function next_y(y, dir, rows, wrapping) = 
     let(ny = y + _next_y_table[dir])
-    wrapping ? 
-        ny < 1 ? ny + rows : (
-            ny > rows ? ny % rows : ny
-        )
-        :
-        ny;
+    wrapping ? (ny < 0 ? ny + rows : ny % rows) : ny;
     
 // go right and carve the right wall
 function carve_right(x, y, maze) = [
@@ -94,7 +84,7 @@ function carve_top(x, y, maze) = [
 function carve_left(x, y, maze, columns) = 
     let(
         x_minus_one = x - 1,
-        nx = x_minus_one < 1 ? x_minus_one + columns : x_minus_one
+        nx = x_minus_one < 0 ? x_minus_one + columns : x_minus_one
     )
     [for(b = maze) [get_x(b), get_y(b)] == [nx, y] ? [nx, y, 1, 0] : b]; 
 
@@ -102,7 +92,7 @@ function carve_left(x, y, maze, columns) =
 function carve_bottom(x, y, maze, rows) = 
     let(
         y_minus_one = y - 1,
-        ny = y_minus_one < 1 ? y_minus_one + rows : y_minus_one
+        ny = y_minus_one < 0 ? y_minus_one + rows : y_minus_one
     )
     [for(b = maze) [get_x(b), get_y(b)] == [x, ny] ? [x, ny, 2, 0] : b]; 
 
diff --git a/src/maze/_impl/_mz_hamiltonian_impl.scad b/src/maze/_impl/_mz_hamiltonian_impl.scad
index 4b7a6885..110d4a62 100644
--- a/src/maze/_impl/_mz_hamiltonian_impl.scad
+++ b/src/maze/_impl/_mz_hamiltonian_impl.scad
@@ -2,22 +2,22 @@ use <../../util/has.scad>;
 
 function _mz_hamiltonian_top(x, y) =
     let(
-        nx = (x - 1) * 2,
-        ny = (y - 1) * 2
+        nx = x * 2,
+        ny = y * 2
     )
     [[nx, ny + 2], [nx + 1, ny + 2], [nx + 2, ny + 2]];
 
 function _mz_hamiltonian_right(x, y) =
     let(
-        nx = (x - 1) * 2,
-        ny = (y - 1) * 2
+        nx = x * 2,
+        ny = y * 2
     )
     [[nx + 2, ny + 2], [nx + 2, ny + 1], [nx + 2, ny]];
     
 function _mz_hamiltonian_top_right(x, y) =
     let(
-        nx = (x - 1) * 2,
-        ny = (y - 1) * 2
+        nx = x * 2,
+        ny = y * 2
     )
     [[nx, ny + 2], [nx + 1, ny + 2], [nx + 2, ny + 2], [nx + 2, ny + 1], [nx + 2, ny]];
 
diff --git a/src/maze/_impl/_mz_hex_walls.scad b/src/maze/_impl/_mz_hex_walls.scad
index 3fb0d0ec..0e153a79 100644
--- a/src/maze/_impl/_mz_hex_walls.scad
+++ b/src/maze/_impl/_mz_hex_walls.scad
@@ -33,8 +33,8 @@ function _row_wall(cell_radius, x_cell, y_cell) =
     
 function _build_cell(cell_radius, block) = 
     let(
-        x = _get_x(block) - 1,
-        y = _get_y(block) - 1,
+        x = _get_x(block),
+        y = _get_y(block),
         walls = concat(
             _row_wall(cell_radius, x, y),
             [_is_top_wall(block) || _is_top_right_wall(block) ? _top(cell_radius) : []],
diff --git a/src/maze/_impl/_mz_initialize.scad b/src/maze/_impl/_mz_initialize.scad
index b365a28c..f6c20953 100644
--- a/src/maze/_impl/_mz_initialize.scad
+++ b/src/maze/_impl/_mz_initialize.scad
@@ -2,8 +2,8 @@ use <_mz_comm.scad>;
 
 // create a starting maze for being visited later.
 function _rc_maze(rows, columns) =  [
-    for(y = [1:rows]) 
-        for(x = [1:columns]) 
+    for(y = [0:rows - 1]) 
+        for(x = [0:columns - 1]) 
             block(
                 x, y, 
                 // all blocks have top and right walls
@@ -19,9 +19,9 @@ function _mz_mask(mask) =
         columns = len(mask[0])
     )
     [
-        for(y = [1:rows])
-            for(x = [1:columns])
-                mask[rows - y][x - 1] == 0 ?
+        for(y = [0:rows - 1])
+            for(x = [0:columns - 1])
+                mask[rows - y - 1][x] == 0 ?
                     block(
                         x, y, 						
                         4, // mask
@@ -31,8 +31,7 @@ function _mz_mask(mask) =
                     block(
                         x, y, 
                         // all blocks have top and right walls
-                        3, 
-                        // unvisited
+                        3, // unvisited
                         false 
                     )
     ];
\ No newline at end of file
diff --git a/src/maze/_impl/_mz_square_walls_impl.scad b/src/maze/_impl/_mz_square_walls_impl.scad
index d63ee2bd..26961f25 100644
--- a/src/maze/_impl/_mz_square_walls_impl.scad
+++ b/src/maze/_impl/_mz_square_walls_impl.scad
@@ -2,7 +2,7 @@ use <_mz_comm.scad>;
 
 function _square_walls(block, block_width) = 
     let(
-        loc = [get_x(block) - 1, get_y(block) - 1] * block_width,
+        loc = [get_x(block), get_y(block)] * block_width,
         top = top_wall(block) || top_right_wall(block) ? [[0, block_width] + loc, [block_width, block_width] + loc] : [],
         right = right_wall(block) || top_right_wall(block) ? [[block_width, block_width] + loc, [block_width, 0] + loc] : []
     )
diff --git a/src/maze/mz_hamiltonian.scad b/src/maze/mz_hamiltonian.scad
index 4b5c17dc..ed533281 100644
--- a/src/maze/mz_hamiltonian.scad
+++ b/src/maze/mz_hamiltonian.scad
@@ -28,4 +28,4 @@ function mz_hamiltonian(rows, columns, start, seed) =
         ),
         dot_pts = dedup(sort(all, by = "vt"), sorted = true)
     )
-    _mz_hamiltonian_travel(dot_pts, start + [-1, -1], rows * columns * 4);
\ No newline at end of file
+    _mz_hamiltonian_travel(dot_pts, start, rows * columns * 4);
\ No newline at end of file
diff --git a/src/maze/mz_square_blocks.scad b/src/maze/mz_square_blocks.scad
index 1644aa2c..cf51a9d7 100644
--- a/src/maze/mz_square_blocks.scad
+++ b/src/maze/mz_square_blocks.scad
@@ -1,7 +1,7 @@
 use <_impl/_mz_blocks_impl.scad>;
 use <mz_square_initialize.scad>;
 
-function mz_square_blocks(rows, columns, start = [1, 1], maze, x_wrapping = false, y_wrapping = false, seed) = 
+function mz_square_blocks(rows, columns, start = [0, 0], maze, x_wrapping = false, y_wrapping = false, seed) = 
     go_maze( 
         start[0], start[1],   // starting point
         is_undef(maze) ? mz_square_initialize(rows, columns) : maze,