Author: Andrew Spear | Website: http://www.etheory.co.nz

The Actions

The basic idea is that we have to calculate the angle from the eye position to the mouse position and then rotate the eye by that angle. To do this we need to get out the old school text books and look up some trigonometry! Luckily I have already done this for you, remember this from your high school days ... ? ; if tanA = a/b ; then A = tan-1 (a/b) ... No? Well Macromedia did and they have added support for these functions and plenty more into Flash5. So basicly, we can calculate angle A if we get distances a and b, to get this we can use the following code to frame one of our movie:

a = eye._y-_ymouse;
b = eye._x-_xmouse;

Now, to turn those distances into angle A we can use this code:

angleA = Math.atan2(a, b);

The only problem is that this gives you the angel not in degrees but in “radians”, another way of measuring angles. To convert angleA into degrees we use this line:

degrees = angleA/(Math.pi/180);

Now we have the angle in degrees that the eye needs to rotate. All that remains is to rotate the eye by the angle “degrees” using this code:

setProperty ("eye", _rotation, degrees);

Now if you test your movie the left eye should turn around and follow your cursor where ever it goes. Finally you need to make a second copy of this entire code to make the second eye move also - you will need to change the value names to something different so they dont get mixed up. Here is the final code that should be in frame one of your actions layer:

a = eye._y-_ymouse;
b = eye._x-_xmouse;
angleA = Math.atan2(a, b);
degrees = angleA/(Math.pi/180);
setProperty ("eye", _rotation, degrees);

a2 = eye2._y-_ymouse;
b2 = eye2._x-_xmouse;
angleA2 = Math.atan2(a2, b2);
degrees2 = angleA2/(Math.pi/180);
setProperty ("eye2", _rotation, degrees2);

Now test your movie and see that it is working, if not check that it is the same as LookingFinal.fla which is also included with this tutorial and has the script working. But all that is just for starters...

» Level Advanced

Added: 2002-01-08 Rating: 9 Votes: 208 1 2 3 4 5 6 7 8 9 10 (10 being the highest) Thank you for voting! We have encountered an error. Please try again later. You've already voted.

» Author

Andrew is the creative director, technical director and general big boss man at eTheory - a web, multimedia and graphic design company based in New Zealand. He has a Diploma in Visual Communications and Design under his belt on top of a long history in html, php and mySQL.

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