 
 		    if ((nuv.x >= -markEdge) && (nuv.x <= markEdge))
 		    {
-		    	float v = noise(screenPos) + 1.;
+		    	float n = noise(screenPos);
+		    	float v = n > .3 ? n + 1.: 0.;
 		        c += float4(v, v, v, v);
 		    }
 
 		    if (nuv.y > -markEdge && nuv.y < markEdge)
 		    {
-		    	float v = noise(screenPos) + 1.;
+		    	float n = noise(screenPos);
+		    	float v = n > .3 ? n + 1.: 0.;
 		        c += float4(v, v, v, v);
 		    }
 

		}

		float4 plot (float2 uv, float2 screenPos, float y, float absScoreResult)
		{
			const float edge = 0.025 * absScoreResult;
			
			if (isnan(y))
				return float4(0., 0., 0., 0.);
		
		    float dist = abs(uv.y - y);
			
			if (isnan(dist))
				return float4(0., 0., 0., 0.);

		    if (dist < edge)
		    {
		    	float v = noise(screenPos) + 1.;
		        return float4(v, v, v, v);
		    }



		float noise (float2 p)
		{
			p *= 800.;
		    float2 i = floor(p);
		    float2 f = frac(p);
		    f *= f * (3.0 - 2.0 * f);
