float srgb2linear(float x) {
    // sRGB to linear conversion
    float lower = x / 12.92;
    float upper = pow((x + 0.055f) / 1.055f, 2.4f);

    return mix(lower, upper, step(0.04045f, x));
}

float linear2srgb(float x) {
    // Linear to sRGB conversion.
    float lower = 12.92 * x;
    float upper = 1.055 * pow(x, 1.0f / 2.4f) - 0.055f;

    return mix(lower, upper, step(0.0031308f, x));
}