o3de/Gems/Atom/Feature/Common/Assets/Shaders/SplashScreen/SplashScreenPass.azsl

/*
 * Copyright (c) Contributors to the Open 3D Engine Project.
 * For complete copyright and license terms please see the LICENSE at the root of this distribution.
 *
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 */

#include <Atom/Features/PostProcessing/FullscreenVertexUtil.azsli>
#include <Atom/Features/SrgSemantics.azsli>

ShaderResourceGroup PassSrg : SRG_PerPass_WithFallback
{
    Sampler m_imageSampler
    {
        AddressU = Clamp;
        AddressV = Clamp;
        AddressW = Clamp;
    };

    Texture2D<float4> m_splashScreenImage;

    struct SplashScreenParams
    {
        float m_fadingFactor;
    } m_splashScreenParams;
}

struct VSInput
{
    uint m_vertexIndex : SV_VertexID;
};

struct VSOutput
{
    float4 m_position : SV_Position;
    float2 m_uv : UV0;
};

struct PSOutput
{
    float4 m_color : SV_Target0;
};

VSOutput MainVS(VSInput vsInput)
{
    VSOutput OUT;

    float4 posTex = GetVertexPositionAndTexCoords(vsInput.m_vertexIndex);
    OUT.m_position = float4(posTex.x, posTex.y, 0.0, 1.0);
    OUT.m_uv = float2(posTex.z, posTex.w);
    return OUT;
}

PSOutput MainPS(VSOutput psInput)
{
    PSOutput OUT;

    float4 color = PassSrg::m_splashScreenImage.Sample(PassSrg::m_imageSampler, psInput.m_uv);
    OUT.m_color = float4(color.rgb * PassSrg::m_splashScreenParams.m_fadingFactor, color.a);

    return OUT;
}