//#version 420 // Keep it for editor detection

/*
** Contrast, saturation, brightness
** Code of this function is from TGM's shader pack
** http://irrlicht.sourceforge.net/phpBB2/viewtopic.php?t=21057
** TGM's author comment about the license (included in the previous link)
** "do with it, what you want! its total free!
** (but would be nice, if you say that you used my shaders  :wink: ) but not necessary"
*/

#ifdef FRAGMENT_SHADER

in vec4 PSin_p;
in vec2 PSin_t;
in vec4 PSin_c;

layout(location = 0) out vec4 SV_Target0;

// For all settings: 1.0 = 100% 0.5=50% 1.5 = 150%
vec4 ContrastSaturationBrightness(vec4 color)
{
    const float sat = SB_SATURATION / 50.0;
    const float brt = SB_BRIGHTNESS / 50.0;
    const float con = SB_CONTRAST / 50.0;

    // Increase or decrease these values to adjust r, g and b color channels separately
    const float AvgLumR = 0.5;
    const float AvgLumG = 0.5;
    const float AvgLumB = 0.5;

    const vec3 LumCoeff = vec3(0.2125, 0.7154, 0.0721);

    vec3 AvgLumin = vec3(AvgLumR, AvgLumG, AvgLumB);
    vec3 brtColor = color.rgb * brt;
    float dot_intensity = dot(brtColor, LumCoeff);
    vec3 intensity = vec3(dot_intensity, dot_intensity, dot_intensity);
    vec3 satColor = mix(intensity, brtColor, sat);
    vec3 conColor = mix(AvgLumin, satColor, con);

    color.rgb = conColor;
    return color;
}


void ps_main()
{
    vec4 c = texture(TextureSampler, PSin_t);
    SV_Target0 = ContrastSaturationBrightness(c);
}


#endif