radians and turning angles in lamen's terms
Posted: Wed Apr 19, 2006 9:59 pm
This is for all of us who haven't taken trigonometry or calculus yet (my schools' messed up). For whatever reason the mathematicians decided they needed something really confusing to describe parts of a circle because everyone was getting used to the degree system. So what they did was they decided to use pi and put some random number over it and whatnot. I'm sure there's a viable explanation for all this, and I'm sure someone will point it out later, with the original equation, but we don't need it right now. The reason you need to know this is that it frequently comes up in values in halo modding; apparently they liked to use radians instead of degrees to describe angles. why don't you need the equation for this? I have a shortcut. I'm looking right now at the L and R Turning angles of the passenger camera for the warthog. I want to make it double, so that you can see in a circle. Of course, I never thought "just make it be the driver's value (0), and it'll move like that," but hey, it was worth it. So, I took out a calculator and doubled the value they have put in for each (1.57079637). guess what I get? 3.1415927. For those of you who don't know, that is the first 7 correct digits of pi and a rounded last digit. What does this mean? It means that for almost all (but probably all) aspects that deal with angles or turning angles, etc. in tags have a value 3.141592653589793238626... you get the picture, that equals 180 degrees. This can be shortened to 3.1415927, with unnoticeable differences (so long as the original value wasn't extremely tiny. this denotes a smaller radian scale that sometimes crops up). This helps with cameras and yaw, pitch, and roll most. Now that we have this all straightened out, you can effectively broaden or shrink a camera's range of movement, reposition a turret to face backwards on spawn with ease, and even completely reconfigure a boarding marker to turn the boarder upside-down! just remember that 1.57079637 is 90 degrees, 3.1415927 is 180, and 6.28318548 is 360 degrees, and you're golden!
edit: also, if you aren't getting the effect you desire, you are ignoring the value that was already in there. The radians used by the bungie team seem to be much much smaller than that of regular radians in some places. However, like 540 degrees in one direction being the same as 180 degrees in one direction, big values work. If you can't factor in the original value but want something to be completely reversed, just take the reciprocal of the original value. it helps to do this with a computer calculator, because it has no limit or a larger limit on how much you can type in. Put in 1, then divided by, and then the original number. if you have an original number with something like E-10 in it (which you probably will), you are going to count out 10 decimal places from the decimal point to the right, filling the last one in with the number before the E. You will get a really huge number, but it will work every time.
hope this helps someone.
edit: also, if you aren't getting the effect you desire, you are ignoring the value that was already in there. The radians used by the bungie team seem to be much much smaller than that of regular radians in some places. However, like 540 degrees in one direction being the same as 180 degrees in one direction, big values work. If you can't factor in the original value but want something to be completely reversed, just take the reciprocal of the original value. it helps to do this with a computer calculator, because it has no limit or a larger limit on how much you can type in. Put in 1, then divided by, and then the original number. if you have an original number with something like E-10 in it (which you probably will), you are going to count out 10 decimal places from the decimal point to the right, filling the last one in with the number before the E. You will get a really huge number, but it will work every time.
hope this helps someone.
You keep moving higher and higher on my imaginary list of 1337 people. 