uniform sampler2D texture0;

void main()
{

	float distance = length(gl_TexCoord[0].xy - vec2(0.5,0.5)) * 2.0;
	
	float strength = 0.1;
	float intensity = strength / (distance * distance) - strength;
	gl_FragColor = vec4(gl_Color.r, gl_Color.g, gl_Color.b, intensity);
}