<@include gpu/Config.slh@>
<$VERSION_HEADER$>
//  Generated on <$_SCRIBE_DATE$>
//
//  simple_transparent_textured_unlit_fade.frag
//  fragment shader
//
//  Created by Olivier Prat on 06/05/17.
//  Copyright 2017 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/Color.slh@>

<@include Fade.slh@>

<@include render-utils/ShaderConstants.h@>

// the albedo texture
LAYOUT(binding=0) uniform sampler2D originalTexture;

layout(location=RENDER_UTILS_ATTR_COLOR) in vec4 _color;
layout(location=RENDER_UTILS_ATTR_TEXCOORD01) in vec4 _texCoord01;
#define _texCoord0 _texCoord01.xy
#define _texCoord1 _texCoord01.zw
layout(location=RENDER_UTILS_ATTR_POSITION_WS) in vec4 _positionWS;

layout(location=0) out vec4 _fragColor0;

// Declare after all samplers to prevent sampler location mix up with originalTexture
<$declareFadeFragmentInstanced()$>

void main(void) {
    vec3 fadeEmissive;
    FadeObjectParams fadeParams;

    <$fetchFadeObjectParamsInstanced(fadeParams)$>
    applyFade(fadeParams, _positionWS.xyz, fadeEmissive);

    vec4 texel = texture(originalTexture, _texCoord0);
    texel = mix(texel, color_sRGBAToLinear(texel), float(_color.a <= 0.0));
    texel.rgb *= _color.rgb;
    texel.a *= abs(_color.a);

    _fragColor0 = vec4(texel.rgb + fadeEmissive, texel.a);
}