#version 330

uniform sampler2D color;

in vec2 P;
in vec2 uv;
out vec3 pixel;

void main()
{
	// retrieve input pixel
	pixel = texture( color, uv ).rgb;
	// darken towards edges
	float dx = P.x - 0.5, dy = P.y - 0.5;
	float distance = sqrt( dx * dx + dy * dy );
	float scale = 1 - max( 0, distance * 1.8 - 0.8 );
	pixel *= scale;
}

// EOF