<@include gpu/Config.slh@>
<$VERSION_HEADER$>
//  Generated on <$_SCRIBE_DATE$>
//
//  overlay3D_translucent.slf
//  fragment shader
//
//  Created by Sam Gateau on 6/16/15.
//  Copyright 2015 High Fidelity, Inc.
//
//  Distributed under the Apache License, Version 2.0.
//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//

<@include model/Light.slh@>
<$declareLightBuffer()$>
<$declareLightAmbientBuffer()$>

<@include LightingModel.slh@>

<@include LightDirectional.slh@>
<$declareLightingDirectional()$>

<@include gpu/Transform.slh@>
<$declareStandardCameraTransform()$>

vec4 evalGlobalColor(float shadowAttenuation, vec3 position, vec3 normal, vec3 albedo, float metallic, vec3 fresnel, float roughness, float opacity) {

    // Need the light now
    Light light = getLight();
    vec3 lightDirection = getLightDirection(light);
    vec3 lightIrradiance = getLightIrradiance(light);

    LightAmbient ambient = getLightAmbient();

    TransformCamera cam = getTransformCamera();
    vec3 fragNormal;
    <$transformEyeToWorldDir(cam, normal, fragNormal)$>
    vec3 fragEyeVectorView = normalize(-position);
    vec3 fragEyeDir;
    <$transformEyeToWorldDir(cam, fragEyeVectorView, fragEyeDir)$>

    vec3 color = opacity * albedo * getLightColor(light) * getLightAmbientIntensity(ambient);

    // Directional
    vec3 directionalDiffuse;
    vec3 directionalSpecular;
    evalLightingDirectional(directionalDiffuse, directionalSpecular, lightDirection, lightIrradiance, fragEyeDir, fragNormal, roughness, metallic, fresnel, albedo, shadowAttenuation);
    color += directionalDiffuse;
    color += directionalSpecular / opacity;

    return vec4(color, opacity);
}

uniform sampler2D originalTexture;

in vec2 _texCoord0;
in vec4 _position;
in vec3 _normal;
in vec3 _color;
in float _alpha;

out vec4 _fragColor;

void main(void) {
    vec4 albedo = texture(originalTexture, _texCoord0);

    vec3 fragPosition = _position.xyz;
    vec3 fragNormal = normalize(_normal);
    vec3 fragAlbedo = albedo.rgb * _color;
    float fragMetallic = 0.0;
    vec3 fragSpecular = vec3(0.1);
    float fragRoughness = 0.9;
    float fragOpacity = albedo.a * _alpha;

    vec4 color =  evalGlobalColor(1.0,
        fragPosition,
        fragNormal,
        fragAlbedo,
        fragMetallic,
        fragSpecular,
        fragRoughness,
        fragOpacity);

    // Apply standard tone mapping
    _fragColor = vec4(pow(color.xyz, vec3(1.0 / 2.2)), color.w);
}