I'm able to rotate my sprite with:

    if(key[KEY_Q])
      _angle--;
    if(key[KEY_E])
      _angle++;

rotate_sprite(buffer, _sprite, _position.X, _position.Y, itofix(_angle));

I have a vector for the position of the sprite. Using the above to rotate, how can I get the direction vector so when I move forward it moves the direction that the sprite is rotated? I'd sure it's fairly easy and I just can't find anything.

Or, based on the angle, how can I get the direction vector?

You should have a velocity on the x and y axis for the sprite, and then do this:

vx = cos(angle) * speed;
vy = sin(angle) * speed;

Where speed is the speed by which the sprite should be moving. Then you update the x and y values by the vx,vy values:

_position.X += vx;
_position.Y += vy;

And youre done!

Oh ok. I do have a velocity, and I also have a direction vector, but it seems since I have the angle variable I don't need the direction vector. Thanks.

Also, that would call cos() and sin() each cycle. I imagine I could call those and store the value in a variable only when I rotate right?

What variables do I need these declared as? I'm getting errors about fixed and such and when I make the angle 'fix' and the vectors float or anything else I get strange results.

I have my angle init to 0 and when I use that to move forward it moves right. ie I have it so when you press the W key it sets the speed value to > 0 to start the movement.

1. Yes you could calculate the new position only when the ship is rotated. That is a good idea.

2. Well sin() and cos() take floats. So you could make _angle a float and then use ftofix() when calling rotate_sprite().

3. Hmm... Dont know about this one. Try starting with 90 degrees.

OK, I must be missing something. Here is my player code, would be great if someone could take a look and let me know what I'm doing wrong.

The sprite does rotate, but the direction of moving doesn't work correctly.

For your move() function doesn't seem to be truly using your _velocity. I would suggest something similar to:

  void move()
  {
    _velocity.X = cos(_angle) * _speed;
    _velocity.Y = sin(_angle) * _speed;

    _position.X += _velocity.X;
    _position.Y += _velocity.Y;
  }

Could you also explain

and say WHAT isn't working?

I must be missing something. That looks the same except you have ) after speed which shouldn't compile since there is no matching (.

I don't know what isn't working or what it's doing. I just know it's not moving it in the right direction. When my guy is facing up, and I try to move (I don't rotate yet) then he goes right.

[EDIT]

OK, something that seems odd. When the angle is 0, cos(angle) is returning a 1, and that gets multiplies by the speed which is .5 making the _velocity.X = to .5, which isn't right I'm thinking, because that makes my image go right, when the image I have visually is pointing up.

What direction is your BITMAP *_sprite stored? You may need to rotate the sprite's image by 90 degrees. The "unturned" direction should be facing right when you have _angle=0.0, it should be facing up when _angle=PI/2 (or in the case of Allegro rotations, 128/2, or 64.0).

And the ")" artifact was something that happened when copying/pasting; sorry. I'll edit my post and fix that typo.

EDIT: Sorry; I guess I had not correctly read your code post, so I had re-keyed what you already had.

So please disregard that first bit; I thought your math was wrong, but it turns out, you were correct all along. The relevant thing is that I think your sprite is simply turned 90 degrees. What direction does it go if you use your Q/E keys and accelerate? Does it go "straight" and even rotate correctly, but simply have the bitmap facing the wrong direction?

My bitmap is stored normally I guess. I created a top down bitmap where you are looking directly down on a person. So you see hit head, shoulders, adn a gun that is pointing "up" or forward.

When angle is 0 the image is facing up. In my code I init angle to 0, and it uses that in rotate_sprite. So if angle is 0 it seems rotate_sprite just draws it normally (up), but moving makes it go right. So how do I rotate my bitmap yet not the angle? Seems I need the bitmap to be facing right at first.

When I move and rotate, sometimes it seems to go the right away and sometimes it doesn't. Seems odd.

[EDIT]

Ok, I rotated the image in the paint editor so now it starts out looking right. So now if I move forward and don't rotate it works by moving right and looks visually right. BUT, if I press Q once then move again the character starts moving up/left, when visually he should move up/right.

Hmm maybe it's because the sprite is rotating around the top/left corner instead of the center of the sprite? I assume rotate_sprite() is doing the rotation around the center of the sprite, and my cos()/sin() is doing it around the top/left of teh sprite.

[EDIT] Nevermind, I read wrong