From: "Christopher Nelson" <paradox AT gye DOT satnet DOT net>
To: <djgpp AT delorie DOT com>
Subject: Re: Calculating direction to shoot in
Date: Sat, 1 May 1999 20:27:53 -0600
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Reply-To: djgpp AT delorie DOT com

>I am programming a 2d space game. The game is seen from aboce and the
>player can rotate his ship so that he can travel in any direction, not
>just up, down, left and right. The problem is: How do I calculate the
>direction/angle the computer controlled enemies have to shoot in to hit
>the player? For example: The player is at coordinates (101, 254) and the
>enemy is at (235, 456). How can I calculate the angle between them?


if i remember correctly, you should be able to take the arctangent of the
slope between the two vectors, and that will give your angle.

e.g. angle = arctan((456-254)/(235-101));

in other words, the angle is equal to the arc tangent of the slope.

slope = rise / run

rise = (253-101);
run = (456-254);

it's something like this anyway.  :-)

    -={C}=-