<@include gpu/Config.slh@>
<$VERSION_HEADER$>
//  Generated on <$_SCRIBE_DATE$>
//
//  forward_model.frag
//  fragment shader
//
//  Created by Sam Gateau on 2/15/2016.
//  Copyright 2014 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 gpu/Transform.slh@>
<@include graphics/Material.slh@>
<@include graphics/MaterialTextures.slh@>
<@include render-utils/ShaderConstants.h@>
<@include ForwardGlobalLight.slh@>

<$declareEvalSkyboxGlobalColor()$>


<$declareStandardCameraTransform()$>

<$declareMaterialTextures(ALBEDO, ROUGHNESS, _SCRIBE_NULL, METALLIC, EMISSIVE, OCCLUSION)$>

layout(location=RENDER_UTILS_ATTR_POSITION_ES) in vec4 _positionES;
layout(location=RENDER_UTILS_ATTR_TEXCOORD01) in vec4 _texCoord01;
#define _texCoord0 _texCoord01.xy
#define _texCoord1 _texCoord01.zw
layout(location=RENDER_UTILS_ATTR_NORMAL_WS) in vec3 _normalWS;
layout(location=RENDER_UTILS_ATTR_COLOR) in vec4 _color;

layout(location=0) out vec4 _fragColor0;

void main(void) {
    Material mat = getMaterial();
    BITFIELD matKey = getMaterialKey(mat);
    <$fetchMaterialTexturesCoord0(matKey, _texCoord0, albedoTex, roughnessTex, _SCRIBE_NULL, metallicTex, emissiveTex)$>
    <$fetchMaterialTexturesCoord1(matKey, _texCoord1, occlusionTex)$>

    float opacity = 1.0;
    <$evalMaterialOpacity(albedoTex.a, opacity, matKey, opacity)$>;
    <$discardTransparent(opacity)$>;

    vec3 albedo = getMaterialAlbedo(mat);
    <$evalMaterialAlbedo(albedoTex, albedo, matKey, albedo)$>;
    albedo *= _color.rgb;

    float roughness = getMaterialRoughness(mat);
    <$evalMaterialRoughness(roughnessTex, roughness, matKey, roughness)$>;

    vec3 emissive = getMaterialEmissive(mat);
    <$evalMaterialEmissive(emissiveTex, emissive, matKey, emissive)$>;

    float metallic = getMaterialMetallic(mat);
    <$evalMaterialMetallic(metallicTex, metallic, matKey, metallic)$>;
    vec3 fresnel = getFresnelF0(metallic, albedo);

    vec3 fragPosition = _positionES.xyz;
    vec3 fragNormal = normalize(_normalWS);

    TransformCamera cam = getTransformCamera();

    vec4 color = vec4(evalSkyboxGlobalColor(
        cam._viewInverse,
        1.0,
        occlusionTex,
        fragPosition,
        fragNormal,
        albedo,
        fresnel,
        metallic,
        roughness),
        opacity);
    color.rgb += emissive * isEmissiveEnabled();

    _fragColor0 = color;
}