diff --git a/solidify/level.c b/solidify/level.c
index 077fbce..43175d4 100644
--- a/solidify/level.c
+++ b/solidify/level.c
@@ -8,6 +8,9 @@
 #include "level.h"
 
 
+#define	NEAR	1
+
+
 static void draw_map(GtkWidget *widget, struct face *f)
 {
 	int x, y, z;
@@ -27,19 +30,21 @@ static void draw_map(GtkWidget *widget, struct face *f)
 				continue;
 			}
 			z0 = f->z_ref+f->fx*(x-f->sx/2)+f->fy*(y-f->sy/2);
-			if (fabs(z-z0) < 1) {
+			if (fabs(z-z0) < NEAR) {
 				*p++ = 255*fabs(z-z0);
 				*p++ = 255*fabs(z-z0);
 				*p++ = 255;
 				continue;
 			}
 			if (z < z0) {
-				z = 255.0*(z-z0)/(z0-f->a->min_z);
+				z = z > z0-2*NEAR ? 255*(z-z0)/NEAR :
+				    255.0*(z-z0)/(z0-f->a->min_z);
 				*p++ = 255;
 				*p++ = z;
 				*p++ = z;
 			} else {
-				z = 255.0*(z0-z)/(f->a->max_z-z0);
+				z = z < z0+2*NEAR ? 255*(z0-z)/NEAR :
+				    255.0*(z0-z)/(f->a->max_z-z0);
 				*p++ = z;
 				*p++ = 255;
 				*p++ = z;