Ballistic Physics in TGB
by Tyler Slabinski · in Technical Issues · 05/10/2009 (8:08 pm) · 9 replies
After looking through this site, I am still completely stumped on how to make accurate ballistic physics. Currently, my projectile acts like this:
That is not a 'perfect' representation, but it does show the problem. In real life, projectiles go farther at 45 degrees than 90. But I do not understand how this works (I have not entered trigonometry classes yet). Here are my variables:
%speedX (the projectile's linearVelocityX at launch)
%speedY (the projectile's linearVelocityY at launch)
%angle (the angle the projectile is heading at launch)
and here is my code:
Does anyone know what the actual equation is for this?
Here is how the degrees are handles at the moment:
That is not a 'perfect' representation, but it does show the problem. In real life, projectiles go farther at 45 degrees than 90. But I do not understand how this works (I have not entered trigonometry classes yet). Here are my variables:
%speedX (the projectile's linearVelocityX at launch)
%speedY (the projectile's linearVelocityY at launch)
%angle (the angle the projectile is heading at launch)
and here is my code:
if (%angle > 90)
{
%speedX = 90 - (%angle - 90);
}
else
{
%speedX = %angle;
}
%speedY = (%angle - 45)r * -1;Does anyone know what the actual equation is for this?
Here is how the degrees are handles at the moment:
#2
You'll have to adjust the +/- of the %angle to work just right.
What's going on there is basically that cos(angle) is the ratio of the x component to the hypotenuse (which is your total velocity). Likewise for sin and the y component.
05/11/2009 (12:07 pm)
%angle = 45; %totalspeed = 100; %speedx = cos(%angle) * %totalspeed; // cos(45) ~= 0.7071 %speedy = sin(%angle) * %totalspeed; // sin(45) also 0.7071
You'll have to adjust the +/- of the %angle to work just right.
What's going on there is basically that cos(angle) is the ratio of the x component to the hypotenuse (which is your total velocity). Likewise for sin and the y component.
#3
05/11/2009 (12:35 pm)
Ahh, thanks... I wish I was in trigonometry now, I seem to need plenty of help in it. Yet I believe that is all I need...
#4
That is basically what you told me to put in. Yet it seems the projectile shoots in a random direction. If the angle is even slightly off, it shoots almost the exact other way.
05/11/2009 (12:52 pm)
Well... Here is basically my code:function convertVelocity()
{
//Get the power for how far the projectile will go.
$speedX = mCos($angle) * $power;
//Get the height for the projectile.
$speedY = mSin($angle) * $power;
}That is basically what you told me to put in. Yet it seems the projectile shoots in a random direction. If the angle is even slightly off, it shoots almost the exact other way.
#5
%radians = (%angle / 180) * 3.141;
Then do mCos(%radians) instead of %angle.
Radians are a just a different way to describe an angle than degrees. There are 2*pi rads in a circle (which is 360degrees). It's not uncommon for Cos() and Sin() to work with radians.
05/11/2009 (1:15 pm)
Ok, you need to convert your angle to radians.%radians = (%angle / 180) * 3.141;
Then do mCos(%radians) instead of %angle.
Radians are a just a different way to describe an angle than degrees. There are 2*pi rads in a circle (which is 360degrees). It's not uncommon for Cos() and Sin() to work with radians.
#6
05/11/2009 (1:27 pm)
Ahh, well I will just get rid of my mRadToDeg function. I used it because I use degrees easier.
#7
The highlighted ones are currently the only ones correct.
05/11/2009 (2:05 pm)
This is how it acts now:The highlighted ones are currently the only ones correct.
#8
05/12/2009 (12:59 pm)
Bump
#9
05/14/2009 (3:16 pm)
Bump 
Torque Owner Tyler Slabinski