Animation.h

#pragma once
 
#include <string>
 
struct Animation //todo for now just add a bool hasFinished (useful for scripts) and much later may need onStop(when game paused)
{                   // todo also we might need to have setReps/getReps and replace "play_once" with "play_n_times" where we pass 1 more value to call
    typedef enum {
        ANIMTYPE_NONE = 0, // just one animation
        ANIMTYPE_PLAY_N_TIMES = 1, // just iterates over the images one time. it holds the final image when finished.
        ANIMTYPE_LOOPED = 2, // going over the images again and again.
        ANIMTYPE_BACK_FORTH = 3  // iterate from index=0 to maxframe and back again. keeps holding the first image afterwards.
    } animType;
 
    int indexX = 0; // initial position in source texture
    int indexY = 0;
 
 
 
    size_t total_frames = 0;
    float speed = 1.0f;
    animType type = animType::ANIMTYPE_NONE;
    int reps = 0;
 
    int frame_times_played = 0;
    int cur_frame_index = 0;
    float cur_frame_index_f = 0;
    int times_played = 0;
 
    int flow_direction = 1;
 
    bool finished = false;
 
    Animation() 
    {
        
    }
 
    Animation(int ix, int iy , size_t f, float s, const std::string _type, int _reps = 0) // Animation frames look the next number of frames from the index
    {
        indexX = ix;
        indexY = iy;
        total_frames = f;
        speed = s;
 
        type = _type == "play_n_times" ? ANIMTYPE_PLAY_N_TIMES :
            _type == "back_forth" ? ANIMTYPE_BACK_FORTH :
            _type == "looped" ? ANIMTYPE_LOOPED :
            ANIMTYPE_NONE;
        reps = _reps;
    }
 
    Animation(int ix, int iy, size_t f, float s, const animType _type, int _reps = 0) // Animation frames look the next number of frames from the index
    {
        indexX = ix;
        indexY = iy;
        total_frames = f;
        speed = s;
 
        type = _type;
        reps = _reps;
    }
 
    void advanceFrame(float deltaTime) {
        unsigned short prev_frame_index = cur_frame_index;
 
        switch (type) {
        case Animation::animType::ANIMTYPE_LOOPED:
        case Animation::animType::ANIMTYPE_PLAY_N_TIMES:
            cur_frame_index_f += speed * deltaTime;
            cur_frame_index = static_cast<unsigned short>(cur_frame_index_f);
 
            // Check if the frame index has changed - indicates how long we have
            // stayed on the same frame
            if (prev_frame_index != cur_frame_index) {
                frame_times_played = 1;
            }
            else {
                frame_times_played++;
            }
 
            if (cur_frame_index > total_frames - 1) //essentially when we see that now we reach a frame out of total frames we reset it
            {
                times_played++;
                if (reps && times_played >= reps) {
                    finished = true;
                }               
            }
            break;
 
        case Animation::animType::ANIMTYPE_BACK_FORTH:
            if (flow_direction == 1) {
                cur_frame_index_f += speed * deltaTime;
 
                if (cur_frame_index_f > total_frames) {
                    cur_frame_index_f -= speed;
                    flow_direction = -1;
                }
                cur_frame_index = static_cast<unsigned short>(cur_frame_index_f);
            }
            else if (flow_direction == -1) {
                if (cur_frame_index > 0) {
                    cur_frame_index_f -= speed * deltaTime;
                    cur_frame_index = static_cast<unsigned short>(cur_frame_index_f);
                }
                else {
                    times_played++;
                    flow_direction = 1;
                    resetFrameIndex();
                    if (reps && times_played >= reps) {
                        finished = true;
                    }
                }
            }
            // Check if the frame index has changed
            if (prev_frame_index != cur_frame_index) {
                frame_times_played = 1;
            }
            else {
                frame_times_played++;
            }
            break;
 
        case Animation::animType::ANIMTYPE_NONE:
            break;
        }
    }
 
    void resetFrameIndex() {
        cur_frame_index = 0;
        cur_frame_index_f = 0;
        frame_times_played = 0;
    }
 
    bool hasFinished() {
        return finished;
    }
};