[X] My Assistant

[Rohtie]

I have searched alot on google about how to make a bullet that goes with the angle of my turret.
This is the code i have for the bullet... There is something very wrong with it, the bullet seems like it wants to fly to somewhere random. I use sdl + opengl.

CODE

Bullet::Bullet(){
    speed = 2;
    //velocity
    xvel = 0;
    yvel = 0;
    //mouse coordinates
    mx = 0;
    my = 0;
    //offset
    x = SCREEN_HEIGHT/2;
    y = SCREEN_WIDTH/2;
    hyp = 0;
    shoot = 0;
    life = 100;
}

void Bullet::Hevent(){
    //If the mouse moved

    if( event.type == SDL_MOUSEMOTION ) {

    //Get the mouse offsets

    mx = event.motion.x;

    my = event.motion.y;
    }
    //if left mouse button was pressed
    if(event.type == SDL_MOUSEBUTTONDOWN){
    if(event.button.button == SDL_BUTTON_LEFT){
        //hyp = sqrt(pow(mx-x,2)+pow(my-y,2);
        //debug
        printf ("x: %d y: %d mousex: %d mousey: %d Angle: %f \n", x, y, mx, my, Angle);
        shoot = 1;
    }}
}

void Bullet::move(){
    int Radians;
    if(shoot == 1){
        Radians = Angle * PI / 180;
        xvel = speed * cos(Radians);
        yvel = speed * sin(Radians);
        x -= xvel;
        y -= yvel;

/*        xvel = floor(x * speed / hyp);
        yvel = floor(y * speed / hyp);
        x -= xvel;
        y -= yvel;*/
        life--;
    }
    if(life == 0){
        shoot = 0;
        life = 100;
    }
}

void Bullet::show(){
    //Move to offset

    glTranslatef( x, y, 0 );


    //Start quad

    glBegin( GL_QUADS );



    //Set color to white

        glColor4f( 1.0, 1.0, 1.0, 1.0 );



        //Draw bullet

        glVertex3f( 0, 0, 0 );

        glVertex3f( 5, 0, 0 );

        glVertex3f( 5, 5, 0 );

        glVertex3f( 0, 5, 0 );



    //End quad

    glEnd();



    //Reset

    glLoadIdentity();
}

It would be helpful if you give me some mathematic formulas or something simelar.

This post has been edited by Rohtie: 19 Apr, 2009 - 06:17 AM