OpenSpace/modules/autonavigation/transferfunctions.cpp

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 * OpenSpace                                                                             *
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 * Copyright (c) 2014-2019                                                               *
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#include <modules/autonavigation/transferfunctions.h>

#include <ghoul/glm.h>

namespace openspace::autonavigation::transferfunctions {

double linear(double t) { return t; };

double step(double t) { return (t > 0.5); };

double circularEaseOut(double p){
    return sqrt((2 - p) * p);
}

double cubicEaseIn(double t) { return (t*t*t); };

double cubicEaseOut(double t) {
    double p = 1 - t;
    return (p*p*p);
};

double cubicEaseInOut(double t) {
    if (t < 0.5) {
        return 4 * t * t * t;
    }
    else {
        double f = ((2 * t) - 2);
        return 0.5 * f * f * f + 1;
    }
};

double quadraticEaseInOut(double t) {
    if (t < 0.5) {
        return 2 * t * t;
    }
    else {
        return (-2 * t * t) + (4 * t) - 1;
    }
}

double exponentialEaseInOut(double t) {
    if (t == 0.0 || t == 1.0) return t;

    if (t < 0.5) {
        return 0.5 * glm::pow(2, (20 * t) - 10);
    }
    else {
        return -0.5 * glm::pow(2, (-20 * t) + 10) + 1;
    }
};

} // namespace