diff --git a/project/inc_cp437.glsl b/project/inc_cp437.glsl
index 240667b..ece0e9c 100644
--- a/project/inc_cp437.glsl
+++ b/project/inc_cp437.glsl
@@ -302,7 +302,7 @@ bool char(vec2 pos, int code)
     ivec2 subpos = pos2 % 4;
     int v = int(pow(2., subpos.y * 4. + subpos.x));
     int d = int(pos2.y * .25) * 2 + int(pos2.x * .25);
-    return (cp437[code * 4 + d] & v) > 0.;
+    return (cp437[code * 4 + d] & v) > 0;
 }
 
 float char_at(vec2 uv, vec2 pos, int code)
@@ -360,6 +360,7 @@ float write_20(vec2 uv, vec2 pos, int str[20])
 
 float write_int(vec2 uv, vec2 pos, int value, int magnitude)
 {
+    value = max(0, value);
     int i;
     int m = 1;
     float d = 0.;
@@ -374,6 +375,7 @@ float write_int(vec2 uv, vec2 pos, int value, int magnitude)
 
 float write_int_left(vec2 uv, vec2 pos, int value, int magnitude)
 {
+    value = max(0, value);
     int i;
     int m = 1;
     float d = 0.;