[FIXED] Get position of end of angle?

General Discussions
#1

Hey guys, I am once again here because I am stumped on something. In my game, I want to calculate the position of the end of the arm, if you can imagine this, I have the arm rotation angle (from the center of the body), and I have the distance of the arm. Can someone point me in the right direction or give me some pseudo code.

#2

you need to use some trigonometry for this. it will probably involve using cos and sin. you have the length of the arm, which is the hypotenuse , and you have 2 angles. 1 being the arm angle, and the other being the 90 degrees of the triangle you are using for calculation. you can use these knows values to work out the other 2 sides of the triangle, these other 2 sides will be what you add to the x and y position of the body to get the position of the arm.

thats probably not explained well, but thats what you use to work with angles like that in 2d.

#3

or just have a quick read of this 8)
instead of moving the object *speed, move it *armLength

#4

simply if I have the origin 0,0 and angle 50 to calculate the endx endy position at a specific radius I use x = radius * sin(angle) y = radius * cos(angle) fairly simple to perform and to explain it if you think of combining the cosine and sine graphics you end up with a circle.

#5 
int x = Math.sin(armAngle);
int y = Math.cos(armAngle);
#6

All of the previous answers tended to be right :smiley:

int armX = armSourceX + armLength * Math.cos(angle);
int armY = armSourceY + armLength * Math.sin(angle);

lrn2trig

#7

Do you mean this thread?

#8

Dude this is simple, simple stuff. Everyone here has posted correct information. Agro has the most complete answer at this point, but if it still not enough:

As you might notice, this is basically Agro’s answer.

Now you also see why it is indeed a radius. (A radius is a distance)

#9

A few things, you should be able to apply the previous formulas without any problems (apart from converting to radians) , I said radius because the function you are using is a circlular function and it would generally be the radius.

#10

I know the topic title says that you’ve already fixed your issue, but if you want my take on this issue: