#ifdef GL_ES
// Set default precision to medium
precision mediump int;
precision mediump float;
#endif

uniform mat3 n_matrix;
uniform sampler2D texture;

uniform struct Light {
	vec3 position;
	vec3 intensities;
} light;

uniform bool b_transparent;
uniform bool b_light;

varying vec2 v_texcoord;
varying vec3 v_position;
varying vec3 v_normal;

void main()
{
	// variables
	float brightness;

	if(b_light == true)
	{
		// calculate normals in worldspace
		vec3 normal = normalize(n_matrix * v_normal);

		//get the surface - light vector (cause this is a candel)
		vec3 surfaceToLight = light.position - v_position;

		// calculate the brightness depending on the angle
		brightness = dot(normal, surfaceToLight) / (length(surfaceToLight) * length(normal));
		brightness = clamp(brightness, 0, 1);
	}
	else
	{
		brightness = 1;
		light.intensities = vec3(1,1,1);
	}

	// get fragment color from texture
	vec4 surfaceColor = vec4(texture2D(texture, v_texcoord));

	// if not transparent, ignore alpha value and set it to 1
	if(!b_transparent)
		surfaceColor.a = 1.0f;

	// pass the data to ogl
	gl_FragColor = vec4(brightness * light.intensities * surfaceColor.rgb, surfaceColor.a);
}