Compton Custom Shader Case 4

gistfile1.glsl

uniform float opacity;
uniform bool invert_color;
uniform sampler2D tex;

void main() {
	vec4 c = texture2D(tex, gl_TexCoord[0]);
	float eps = 0.004f;
	float eps1 = 1.0f / 255.0f;
	if (invert_color)
		c = vec4(vec3(c.a, c.a, c.a) - vec3(c), c.a);
	// Some Greybird Background Colors: 0xF4F4F4 (Menu bk), 0xFEFEFE (Textbox bk), 0xCECECE (Grey bk)
	if((c.r > 0.807+eps1-eps && c.r < 0.807+eps1+eps &&
	    c.g > 0.807+eps1-eps && c.g < 0.807+eps1+eps &&
	    c.b > 0.807+eps1-eps && c.b < 0.807+eps1+eps) ||
	   (c.r > 0.953+eps1-eps && c.r < 0.953+eps1+eps &&
	    c.g > 0.953+eps1-eps && c.g < 0.953+eps1+eps &&
	    c.b > 0.953+eps1-eps && c.b < 0.953+eps1+eps) ||
	   (c.r > 0.988+eps1-eps && c.r < 0.988+eps1+eps &&
	    c.g > 0.988+eps1-eps && c.g < 0.988+eps1+eps &&
	    c.b > 0.988+eps1-eps && c.b < 0.988+eps1+eps)
	   )
	{ c *= opacity; }
	else {  }
	gl_FragColor = c;
}