Calculating the "push" to align to a vector

Development Programming & Scripting
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1

I know this should be simple but I am having a heck of a time wrapping my head around it. Maybe someone smarter than me can help.

I want to push my flying AI drone to face in the direction of a location. The pawn uses the same thrust system use by the player (axisup 1.0 means full speed look up, etc).

Once I have the Forward vector for the pawn and the direction vector for the target, what is the math to determine the -1 to +1 push value for pitch and yaw? I have tried several things unsuccessfully and I know I am missing something simple. The solutions I find involve simply rotating the actor, which I don’t want to do.

Thanks.

2

Hey @mmcmain
You can use FindLookAtRotation and split the rotation to use these values for your input. Your Start is your current location and your target is your location + direction. Then you would have to check how much pitch/yaw you can get like 10degree/1second with +1. So you would have to calculate how long you have to set an input to reach your target pitch/yaw. You could adjust these values (-1/+1) to reach pitch/yaw targets faster or slower.

3

Thank you for the swift reply.

This is where I started, but I must be using the data incorrectly.

This is what I have for findLookAtRotation:

FindLookAt
FindLookAt729×310 35.4 KB

And this is how I am using it for pitch:

Pitch
Pitch1571×445 95.8 KB

This is obviously wrong as my drone spins forever never looking at the target. Any thoughts on where my error might be?

4

Ok crap, I need to take my current facing into account. I guess I need to compute the relative rotation from my forward vector converted to a rotator? I will try that when I get back from dinner.

5

Hey @mmcmain
What happens if you use FindLookAtRotation and use SetWorldRotation for your Drone with these values? No lerp, no rotation over time , just direct input with the rotator. Which direction does your drone point at?

6

If I do that I get perfect orientation. So the rotator is correct. I just need to know how to use the value of that rotation to apply it to my current facing’s rotation through impulse rather than setting it directly.

7

I think I have it.

FindLookAt
FindLookAt1387×121 50.5 KB

Pitch
Pitch1494×562 131 KB

This makes it align correctly. Thank you for your help! Confirming that LookAtRotation was the correct approach let me keep stepping on weeds until I found the roots.

I need to clean up the lerping a bit and dot product pitch and yaw separately to smooth it out and prevent overshooting, but this is definitely makes the drone point at the correct spot.