#version 120
uniform sampler2D DIFFUSE;
uniform sampler2D MASK;
uniform float intensity = 1.0;

void main()
{
    vec2 UV =  gl_TexCoord[0].st;
    vec4 col4 = texture2D(DIFFUSE, UV, 0.0);
    vec4 colmask = texture2D(MASK, UV, 0.0);
    vec3 col = col4.xyz;

    float a = 1 - pow(1 - col4.a, 3);
    colmask.a = 1 - pow(1 - colmask.a, 3);


    float fa = a * colmask.a;

    float intens = clamp(intensity, 0, 1);
    float intensity2 = intensity - 1.0;
    intensity2 = clamp(intensity2, 0, 0.6);

    fa += colmask.a * intensity2;
    fa = clamp(fa, 0, 1);

    fa = clamp(fa - (1.0 - intens), 0, 1) / intens;

    col *= fa;

    gl_FragColor = vec4(col, fa);
}