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Thread: need help with using trig functions

  1. #1
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    Default need help with using trig functions

    First off I'm new here so I'd like to say nice to meet you all . Now down to business, I'm working on a (2d, birds i view) game but I'm having trouble with interacting with the avatar. I would like to make it so the avatar faces the mouse cursor (so it rotates so the front always is facing the mouse). This is what I have but the code just has the avatar spinning constantly. (Note: I changed some variable names and some of the syntax to make it easier to understand my code without knowledge of the game engine I'm using so any var names or brackets/parenthesis problems aren't an issue.) Thanks in advance for the any help!

    if (mousesX >= avatarsX)
            {
                if(mousesY >= avatarsY)
                    angle = (int)(Math.atan((mousesY - avatarsY) / (mousesX -avatarsX)));
                else
                    angle = (int)(Math.atan((avatarsY - mousesY) / (mousesX - avatarsX)));
            }
            else
            {
                if(mousesY >= avatarsY)
                    angle = (int)(Math.atan(mousesY -avatarsY)/(avatarsX - mousesX));
                else
                    angle = (int)(Math.atan((avatarsY - mousesY) / (avatarsX - mousesX));
     
            }
     
             if(angle != oldAngle)
            {(
                setImage(rotate(getImage() , angle + oldAngle + (180 - (angle + oldAngle)))); //rotate(image, int) rotates image (in this case the avitar)  by int degrees clockwise. setImage(image) displays image (the avatar) and getImage() returns the avatars image
     
                oldAngle += angle;
            }
     
            if (oldAngle == 360)
                oldAngle -= 360;


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: need help with using trig functions

    Can you make a small complete program that compiles, executes and shows the problem?
    If you don't understand my answer, don't ignore it, ask a question.

  3. #3
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    Default Re: need help with using trig functions

    Sorry, I'm not quite sure what you mean. Are you asking to upload an example program that reproduces the problem?

  4. #4
    Super Moderator Norm's Avatar
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    Default Re: need help with using trig functions

    Yes, something that could be used for testing the code.
    If you don't understand my answer, don't ignore it, ask a question.

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