File content as of revision 21:be18f33da757:

#include "Snake.h"
#include "math.h"
#include <complex>

Snake::Snake(float pos_x, float pos_y)
{
    moving = true;
    face = 0;
    hp = 4;
    hitbox.width = 6;
    hitbox.height = 5;
    position.x = pos_x;
    position.y = pos_y;
    sprite_size.width = 6;
    sprite_size.height = 9;
    sprite_size.offset_x = 0;
    sprite_size.offset_y = 4;
    frame.count = 0;
    frame.number = 0;
    frame.max = 6;
    velocity = 0;
}

void Snake::move(float player_x, float player_y)
{
    std::complex<double> pos_diff(player_x - position.x, player_y - position.y); // defining difference in position as a vector
    velocity = velocity_pattern[frame.number]; // Creating slithering effect, changing velocity of movement

    // Setting Face
    if (frame.number == 0) {
        if (abs(pos_diff.real()) > abs(pos_diff.imag())) {
            if (pos_diff.real() > 0) {
                face = 1;
            } else {
                face = 3;
            }
        } else {
            if (pos_diff.imag() > 0) {
                face = 0;
            } else {
                face = 2;
            }
        }
    }

    // Movement, Offset and  Update
    if (face == 0) {
        position.y += velocity;
    } else if (face == 1) {
        position.x += velocity;
    } else if (face == 2) {
        position.y -= velocity;
    } else if (face == 3) {
        position.x -= velocity;
    }

    undo_move_x(matrix_collision_test(position.x, prev_pos.y, 0));
    undo_move_y(matrix_collision_test(prev_pos.x, position.y, 0));

    frame.count++;
    if (frame.count >= 5) {
        frame.count = 0;
        frame.number++;
        if (frame.number >= frame.max) {
            frame.number = 0;
        }
    }
}

int * Snake::get_frame()
{
    return (int *) sprite_snake[face][frame.number];
}