frag shader

#version 150

in vec3 v3LightDirection;
in vec3 v3Direction;
in vec3 c0;
in vec3 c1;

out vec4 color;


float getMiePhase(float fCos, float fCos2, float g, float g2)
{
	return 1.5 * ((1.0 - g2) / (2.0 + g2)) * (1.0 + fCos2) / pow(1.0 + g2 - 2.0 * g * fCos, 1.5);
}

// Calculates the Rayleigh phase function
float getRayleighPhase(float fCos2)
{
	return 0.75 + 0.75 * fCos2;
}
void main()
{
float g= -0.85;
float g2=g*g;

  float fCos = dot(v3LightDirection, v3Direction) / length(v3Direction);

  float fCos2 = fCos * fCos;

 vec3 ccolor =	getRayleighPhase(fCos2) * c0 +
					getMiePhase(fCos, fCos2, g, g2) * c1;

 	color = vec4(ccolor, 1.0);
	color.a = color.b; 
	//color= vec4(0,length(c0),length(c1),1);
}