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Tutorial:Cosine

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Some sine and cosine program. Check it out. More of example code, but useful anyway.

Note that this is code for Fenix versions 0.93 and up. Should the code work for other versions as well, be so kind to note this here.

[edit] Example code

Program cosine;
Const
    seconds       = 2.3;
    ball_width    = 20;
    ball_height   = 20;
    screen_width  = 320;
    screen_height = 200;
    screen_depth  = 8;
    screen_fps    = 60;
    cos_factor    = 2000;
    sin_factor    = 4000;
    timer_spawn   = 0;
    timer_ball    = 1;
Begin

    // make the movement a bit more smooth
    set_fps(screen_fps,0);

    // spawn a ball process every <seconds> seconds with random colors.
    timer[timer_spawn]= seconds*100;
    Repeat
        if(timer[timer_spawn]>=seconds*100)
            timer[timer_spawn]-=seconds*100;
            x = new_map(ball_width,ball_height,screen_depth);
            map_clear(0,x,rgb(rand(0,255),rand(0,255),rand(0,255)));
            ball(x);
        end
        frame;
    Until(key(_esc))

    // kill all other remaining processes and exit
    let_me_alone();
    exit();

End

Process ball(graph)
Private
    int start_time;
Begin

    // remember starting time
    start_time = timer[timer_ball];

    // position the ball according to the passed time (timer[timer_ball])
    Loop
        x = screen_width /2 + cos((timer[timer_ball]-start_time)*cos_factor)
                              * (screen_width /2-ball_width /2);
        y = screen_height/2 + sin((timer[timer_ball]-start_time)*sin_factor)
                              * (screen_height/2-ball_height/2);
        frame;
    End

End

Used in example: set_fps(), new_map(), map_clear(), rand(), key(), let_me_alone(), cos(), sin(), timer, x, y

This will result in something like: