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Accessing a Units net movement speed?

by Stephen Zepp · in RTS Starter Kit · 11/11/2004 (9:20 pm) · 5 replies

I'm playing around with making all units that are in a formation move at the same speed (slowest unit in the formation's speed).

I've added mMoveSpeedLimit to RTSUnit, pack/unpacked it (I think properly), and modified RTSUnit::processTick() to set the v like so:
v = getMin( (mMoveSpeedLimit > 0.0f) ? mMoveSpeedLimit : 5000.0f,
                           data->mMoveSpeed * mNetModifier.mMoveSpeed) * TickSec;
            else
              v = getMin( (mMoveSpeedLimit > 0.0f ) ? mMoveSpeedLimit : 5000.0f, mMoveVelocity) * TickSec;

The intended purpose of that code is to use the normal calculations if mMoveSpeedLimit is 0.0f, otherwise cap it at mMoveSpeedLimit.

I wrote access/console methods to allow script to find the lowest mMoveSpeed of a selection, and as I issue each move command I set the mMoveSpeedLimit to that value.

What I don't quite understand is I guess the use of mMoveSpeed, as opposed to data(block)->mMoveSpeed. It appears that RTSUnit->mMoveSpeed is clamped between 0.0f and 1.0f.

Is there a reason to clamp it, and why do we refer to the datablock's movement speed instead of the RTSUnits mMoveSpeed when performing the move?
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Torque 3D Owner Stephen Zepp
#1
11/11/2004 (9:58 pm)
I got this working (configurable on the move call via script), and will post a set of changes tomorrow (need sleep!).

I'm still curious however what RTSUnit->mMoveSpeed is intended for, since it's clamped down so tightly. As far as I can tell, the movement code only uses the mMovementSpeed (modifed my the NetModifier.moveSpeed), so I think I'm missing why RTSUnit has the var as well.

Associate Kyle Carter
#2
11/12/2004 (10:15 am)
It might be a holdover from the AI code, or maybe it's meant to let you scale down unit speeds... I'll add it to my list of Stuff To Look At. Good eye! :)

Torque 3D Owner Stephen Zepp
#3
11/12/2004 (11:19 am)
Yeah, I was treating my mMoveSpeedLimit the same in all ways as mMoveSpeed. After I triple checked and found out that mMoveSpeed wasn't actually used anywhere, I treated mMoveSpeedLimit as parallel in function to mDataBlock->mMoveSpeed (let it be bigger than 1.0f), and it worked like a champ.

Not only are my various squads in formations now, but they even stay in formation as they move, instead of random paths and speeds to their individual destinations...quite fun!

Torque Owner Josh Williams
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#4
11/12/2004 (11:58 am)
Coolness Stephen. :)

Yes, RTSUnit.mMoveSpeed is left over cruft. Woops! You could either remove it, or make it useful by relying on it instead of the db value. If it's removed, it will save a very slight bit of network traffic. If it's made useful, you can easily set individual unit speeds (without having to use a modifier). I'd probably just remove it myself.

Re: your formation stuff... great! Thanks for posting it in here too, I love to see sharing like that. Hopefully we'll get a whole bunch of this kind of stuff going.

Associate Kyle Carter
#5
11/17/2004 (3:50 pm)
Ok, I blasted it. Thanks for looking into this, guys. The moveSpeedLimit is a great idea, but I don't really want to introduce new functionality in this release, mostly fix brokenness. Next release, though...