<@include gpu/Config.slh@>
<$VERSION_HEADER$>
//  Generated on <$_SCRIBE_DATE$>
//
//  ssao_buildNormals.frag
//
//  Created by Olivier Prat on 09/19/18.
//  Copyright 2018 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 ssao.slh@>
<$declareAmbientOcclusion()$>
<$declareFetchDepthPyramidMap()$>

layout(location=0) in vec2 varTexCoord0;

layout(location=0) out vec4 outFragColor;

void main(void) {
    // Pixel being shaded
    vec2 fragCoord = gl_FragCoord.xy; 
    ivec2 fragPixelPos = ivec2(fragCoord.xy);
    vec2 fragUVPos = varTexCoord0;

    // Stereo side info based on the real viewport size of this pass
    ivec2 sideNormalsSize = ivec2( getNormalsSideSize() );
    ivec4 side = getStereoSideInfoFromWidth(fragPixelPos.x, sideNormalsSize.x);

    vec2 deltaDepthUV = vec2(1.0) / getDepthTextureSideSize(0);

    // From now on, fragUVPos is the UV pos in the side
    fragUVPos = getSideUVFromFramebufferUV(side, fragUVPos);

    // The position and normal of the pixel fragment in Eye space
    vec3 fragPositionES = buildPosition(side, fragUVPos);
    vec3 fragNormalES = buildNormal(side, fragUVPos, fragPositionES, deltaDepthUV);

    outFragColor = vec4(packNormal(fragNormalES), 1.0);
}