Get normals from depth buffer

float3 PS_Gbuffer(float4 pos : SV_POSITION, float2 uv : TEXCOORD) : SV_TARGET {
    float z = ReShade::GetLinearizedDepth(uv);
    float dx = BUFFER_RCP_WIDTH;
    float dy = BUFFER_RCP_HEIGHT;
    float dzdx = (ReShade::GetLinearizedDepth(uv + float2(dx, 0.0)) - ReShade::GetLinearizedDepth(uv + float2(-dx, 0.0))) / (2.0 * dx);
    float dzdy = (ReShade::GetLinearizedDepth(uv + float2(0.0, dy)) - ReShade::GetLinearizedDepth(uv + float2(0.0, -dy))) / (2.0 * dy);
    float3 d = float3(dzdx, -dzdy, z);
    float3 n = normalize(d);
    return n;
    /*float3 lightDirection = float3(1.0, -2.0, 3.0);
    float shading = 0.5 + 0.5 * dot(n, normalize(lightDirection));
    return shading;*/
}