anchor.diff:  		vec4 color1 = texture3D( texture1, v_texcoord );
   		if( color1.r > u_lowerThreshold1 && color1.r <= u_upperThreshold1 )
   		{
  +		    color1.r = ( color1.r - u_lowerThreshold1 ) / ( u_upperThreshold1 - u_lowerThreshold1 );
   			color.rgb =  mix( color.rgb, colormap( color1.rgb, u_colormap1 ), u_alpha1 );
   		}
   	}
  
positive.code: 		vec4 color0 = texture3D( texture0, v_texcoord );
  		if( color0.r > u_lowerThreshold0 && color0.r <= u_upperThreshold0 )
  		{
  			color = vec4( colormap( color0.rgb, u_colormap0 ), 1.0 );
  		}
  	}
  
negative.code: 		vec4 color2 = texture3D( texture2, v_texcoord );
  		if( color2.r > u_lowerThreshold2 && color2.r <= u_upperThreshold2 )
  		{
  		    color2.r = ( color2.r - u_lowerThreshold2 ) / ( u_upperThreshold2 - u_lowerThreshold2 );
  			color.rgb =  mix( color.rgb, colormap( color2.rgb, u_colormap2 ), u_alpha2 );
  		}
  	}
  