diff --git a/src/experimental/_impl/_tiles_wfc_impl.scad b/src/experimental/_impl/_tiles_wfc_impl.scad
index 157c79ac..95ef3626 100644
--- a/src/experimental/_impl/_tiles_wfc_impl.scad
+++ b/src/experimental/_impl/_tiles_wfc_impl.scad
@@ -73,10 +73,11 @@ function _replaceStatesAt(wf, x, y, states) =
 		m_replace(wf_eigenstates(wf), x, y, states)
 	];
 
-function wf_not_collapsed_coords(wf) = 
-    let(eigenstates = wf_eigenstates(wf), we = wf_width(wf) - 1, he = wf_height(wf) - 1, rx = [0:we])
+function wf_not_collapsed_coords(wf, notCollaspedCoords) = 
+    let(eigenstates = wf_eigenstates(wf))
     [
-		for(y = [0:he], x = rx)
+		for(coord = notCollaspedCoords)
+		let(y = coord.y, x = coord.x)
 		if(len(eigenstates[y][x]) != 1) [x, y]
 	];
 
@@ -172,7 +173,7 @@ function generate(nbr_dirs, compatibilities, wf, notCollaspedCoords, collapsing_
 		weights = coord_weights[2],
 		nwf = propagate(nbr_dirs, compatibilities, wf_collapse(wf, coord_weights.x, coord_weights.y, weights), coord_weights)
 	)
-	generate(nbr_dirs, compatibilities, nwf, wf_not_collapsed_coords(nwf), collapsing_method);
+	generate(nbr_dirs, compatibilities, nwf, wf_not_collapsed_coords(nwf, notCollaspedCoords), collapsing_method);
 
 function neighbor_dirs(x, y, width, height) = [
 	if(x > 0)          [-1,  0],   // left
diff --git a/src/experimental/tile_wfc.scad b/src/experimental/tile_wfc.scad
index 0bd1147e..fcb8aea8 100644
--- a/src/experimental/tile_wfc.scad
+++ b/src/experimental/tile_wfc.scad
@@ -7,9 +7,11 @@ function tile_wfc(size, sample, method = "length") =
     let(
         w = size.x,
         h = size.y,
+        rangey = [0:h - 1],
+        rangex = [0:w - 1],
         nbr_dirs = [
-            for(y = [0:h - 1])
-            [for(x = [0:w - 1]) neighbor_dirs(x, y, w, h)]
+            for(y = rangey)
+            [for(x = rangex) neighbor_dirs(x, y, w, h)]
         ],
         // random start
         x = floor(rand(w * 0.25, w * 0.75)),
@@ -17,15 +19,20 @@ function tile_wfc(size, sample, method = "length") =
 		compatibilities = compatibilities_of_tiles(sample),
         wf = wave_function(w, h, weights_of_tiles(sample)),
         all_weights = wf_weights(wf),
-        states = wf_eigenstates_at(wf, x, y),
-		weights = [for(state = states) get_state_weight(all_weights, state)],
+		weights = [for(state = wf_eigenstates_at(wf, x, y)) get_state_weight(all_weights, state)],
         first_collasped_propagated = propagate(
 			nbr_dirs,
 			compatibilities,
 			wf_collapse(wf, x, y, weights), 
             [x, y]
         ),
-        notCollapsedCoords = wf_not_collapsed_coords(first_collasped_propagated)
+        fstp_states = wf_eigenstates(wf),
+        notCollapsedCoords =     [
+            for(y = rangey)
+            let(y_states = fstp_states[y])
+                for(x = rangex) 
+                if(len(y_states[x]) != 1) [x, y]
+        ]
     )
     generate(nbr_dirs, compatibilities, first_collasped_propagated, notCollapsedCoords, collapsing(method));