diff --git a/cuburn/code/iter.py b/cuburn/code/iter.py
index 33ac96c..7a867a2 100644
--- a/cuburn/code/iter.py
+++ b/cuburn/code/iter.py
@@ -92,6 +92,7 @@ void iter(mwc_st *msts, iter_info *infos, float4 *accbuf, float *denbuf) {
     while (nsamps > 0) {
         float xfsel = mwc_next_01(&rctx);
 
+        {{if packer.get("cp.chaos_used")==True}}
         {{for density_row_idx, prior_xform_idx in enumerate(features.std_xforms)}}
         {{for density_col_idx,  this_xform_idx in enumerate(features.std_xforms)}}
         if (last_xf_used == {{prior_xform_idx}} && 
@@ -101,6 +102,13 @@ void iter(mwc_st *msts, iter_info *infos, float4 *accbuf, float *denbuf) {
         } else
         {{endfor}}
         {{endfor}}
+        {{else}}
+        {{for density_col_idx,  this_xform_idx in enumerate(features.std_xforms)}}
+        if (xfsel < {{packer.get("cp.norm_density[%d]" % (density_col_idx))}}) {
+            apply_xf{{this_xform_idx}}(&x, &y, &color, &rctx);
+        } else
+        {{endfor}}
+        {{endif}}
         {
             //printf("%d ",last_xf_used);
             denbuf[0] = xfsel;
diff --git a/cuburn/render.py b/cuburn/render.py
index 3d98f84..5b7b403 100644
--- a/cuburn/render.py
+++ b/cuburn/render.py
@@ -46,14 +46,19 @@ class Genome(object):
         # Chaos support
         num_std_xf = len(dens)
         self.chaos_densities = np.zeros( (num_std_xf,num_std_xf) )
+        self.chaos_used = False
         for r in range(num_std_xf):
             chaos_row = np.array([ctypes_genome.chaos[r][c] for c in range(num_std_xf)])
+            if np.any(chaos_row != 1.0):
+                self.chaos_used = True
             chaos_row = chaos_row * dens
             chaos_row /= np.sum(chaos_row)
             chaos_row = [np.sum(chaos_row[:i+1]) for i in range(len(dens))]
             self.chaos_densities[r,:] = chaos_row
         ###############
 
+        dens /= np.sum(dens)
+        self.norm_density = [np.sum(dens[:i+1]) for i in range(len(dens))]
         self.camera_transform = self.calc_camera_transform()
 
     scale = property(lambda cp: 2.0 ** cp.zoom)