# How do you plot an arc?

You know those games where you input angle and velocity and shoot at each other? I am trying to make one but can't figure out the math to make the shots arc. I know that it is something to do with trigenometry (cos, sin, and tan) but I need help!

• : You know those games where you input angle and velocity and shoot at each other? I am trying to make one but can't figure out the math to make the shots arc. I know that it is something to do with trigenometry (cos, sin, and tan) but I need help!
:

Well..

Do like this:

' bullet coordinates
dim bulletX as double, bulletY as double
' bullet's speed in x and y direction
dim bSpeedX as double, bSpeedY as double
' angle and power
dim angle as double, power as double

print "Enter angle: "
input angle

print "Power : "
input power

bSpeedX = cos(angle * 3.141592 / 180) * power
bSpeedY = sin(angle * 3.141592 / 180) * power

' move bullet
bulletX = bulletX + bSpeedX
bulletY = bulletY + bSpeedY

That's it..

Now if you enter angle of 0(zero) and power of 10,
bullet will fly to the right 10 pixels a time.
cos and sin use radians, so you must convert angle from
degrees to radians (angle * PI / 180)

Hope that helped..