https://git.spwbk.site/swatson/rs-rl/raw/master/resources/backing.fs
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#version 330 core
out vec4 FragColor;

in vec2 TexCoords;

uniform sampler2D screenTexture;

void main()
{
    vec3 col = texture(screenTexture, TexCoords).rgb;
    FragColor = vec4(col, 1.0);
}