diff --git a/src/experimental/reaction_diffusion.scad b/src/experimental/reaction_diffusion.scad
index e2970765..cecfb8f3 100644
--- a/src/experimental/reaction_diffusion.scad
+++ b/src/experimental/reaction_diffusion.scad
@@ -18,13 +18,13 @@ function init(x, y, n, ix, iy, in) =
 		]
 	];
 
-function gray_scott(u, v, feel, kill, Du, Dv, space_x, space_y) =
+function gray_scott(u, v, feel, kill, Du, Dv, uy_ly, rx_lx, space_x, space_y) =
     let(
 		nuv = [
 			for(y = [0:space_y - 1])
 			let(
-				uy = (y + 1 + space_y) % space_y,
-				ly = (y - 1 + space_y) % space_y,
+				uy = uy_ly[y][0],
+				ly = uy_ly[y][1],
 				row_u = u[y],
 				row_v = v[y],
 				row_uu = u[uy],
@@ -35,36 +35,46 @@ function gray_scott(u, v, feel, kill, Du, Dv, space_x, space_y) =
 			[
 				for(x = [0:space_x - 1])
 				let(
+					rx = rx_lx[x][0],
+					lx = rx_lx[x][1],
 					cu = row_u[x],
 					cv = row_v[x],
-					rx = (x + 1 + space_x) % space_x,
-					lx = (x - 1 + space_x) % space_x,
 					reaction = cu * (cv ^ 2)
 				)
                 [
-					Du * (row_uu[x] + row_u[rx] + row_ul[x] + row_u[lx] - 4 * cu) - reaction + feel * (1 - cu), 
-					Dv * (row_vu[x] + row_v[rx] + row_vl[x] + row_v[lx] - 4 * cv) + reaction - (feel + kill) * cv
+					cu + Du * (row_uu[x] + row_u[rx] + row_ul[x] + row_u[lx] - 4 * cu) - reaction + feel * (1 - cu), 
+					cv + Dv * (row_vu[x] + row_v[rx] + row_vl[x] + row_v[lx] - 4 * cv) + reaction - (feel + kill) * cv
 				]
 			]
 		]
 	)
 	[
-	    u + [for(row = nuv) [for(uv = row) uv[0]]], 
-		v + [for(row = nuv) [for(uv = row) uv[1]]]
+	    [for(row = nuv) [for(uv = row) uv[0]]], 
+		[for(row = nuv) [for(uv = row) uv[1]]]
 	];
 	
-function _reaction_diffusion(feel, kill, generation, u, v, Du, Dv, space_x, space_y) = 
+function _reaction_diffusion(feel, kill, generation, u, v, Du, Dv, uy_ly, rx_lx, space_x, space_y) = 
     generation == 0 ? [u, v] :
-	let(nuv = gray_scott(u, v, feel, kill, Du, Dv, space_x, space_y))
-	_reaction_diffusion(feel, kill, generation - 1, nuv[0], nuv[1], Du, Dv, space_x, space_y);
+	let(nuv = gray_scott(u, v, feel, kill, Du, Dv, uy_ly, rx_lx, space_x, space_y))
+	_reaction_diffusion(feel, kill, generation - 1, nuv[0], nuv[1], Du, Dv, uy_ly, rx_lx, space_x, space_y);
 	
 function reaction_diffusion(
     feel, kill, generation, space_size = [50, 50], init_size = [10, 10], init_u = 0.5, init_v = 0.25, Du = 0.2, Dv = 0.1) =
 	let(
-		u = init(space_size[0], space_size[1], 1, init_size[0], init_size[1], init_u),
-		v = init(space_size[0], space_size[1], 0, init_size[0], init_size[1], init_v)
+		space_x =  space_size.x,
+		space_y = space_size.y,
+		u = init(space_x, space_y, 1, init_size.x, init_size.y, init_u),
+		v = init(space_x, space_y, 0, init_size.x, init_size.y, init_v),
+		uy_ly = [
+			for(y = [0:space_y - 1])
+			[(y + 1 + space_y) % space_y, (y - 1 + space_y) % space_y]
+		],
+		rx_lx = [
+			for(x = [0:space_x - 1]) 
+			[(x + 1 + space_x) % space_x, (x - 1 + space_x) % space_x]
+		]
 	)
-	_reaction_diffusion(feel, kill, generation, u, v, Du, Dv, space_size[0], space_size[1]);
+	_reaction_diffusion(feel, kill, generation, u, v, Du, Dv, uy_ly, rx_lx, space_x, space_y);
 
 
 /*