3DPhysicsCharacterController -- choppy motion?

Author

Message

hendron

8

Years of Service

User Offline

Joined: 20th Dec 2015

Location:

Posted: 16th Jan 2020 00:23

Link

I'm experiencing choppy motion with the 3DPhysicsCharacterController, in that it appears to stutter a bit at regular time intervals. It seems to be related to the frame rate, as setting different sync rates changes the appearance of the motion, but it's never smooth. I've also found that moving the window changes it as well, similar to changing the sync rate. I'm getting the same issue in both Studio and Classic. Here's a snippet to test (it's especially noticeable when moving left and right).

+ Code Snippet

#constant SW = 1024
#constant SH = 768


SetWindowSize(SW,SH,0)
SetVirtualResolution(SW,SH)
SetSyncRate(60,0)
SetCameraPosition(1,0,128,-256)

ground = CreateObjectPlane(1024,1024)
RotateObjectGlobalX(ground,90)
SetObjectPosition(ground,0,-64,0)
SetObjectColor(ground,64,64,64,255)

player = CreateObjectBox(32,64,32)
SetObjectPosition(player,0,32,0)
FixObjectPivot(player)

Create3DPhysicsWorld()
Create3DPhysicsStaticPlane(0,1,0,-64)
ovec = CreateVector3(0,32,0)
rvec = CreateVector3(0,0,0)
Create3DPhysicsCharacterController(player,1,ovec,rvec,0.5)

repeat

	Step3DPhysicsWorld()
	
	move# = (GetRawKeyState(68) - GetRawKeyState(65))
	strafe# = (GetRawKeyState(87) - GetRawKeyState(83))
	Move3DPhysicsCharacterController(player,move#,strafe#,100.0) 

	Print("Move with WASD")
	Print(ScreenFPS())
	Sync()

until GetRawKeyState(27)

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 16th Jan 2020 00:52 Edited at: 16th Jan 2020 02:41

Link

It's very weird. Sometime it seems to go smoothly and sometimes it's choppy, sometimes it starts out choppy and then goes smooth.
If you keep going forward for a bit, then backward for a bit, eventually it smooths out. Not that it's any help though

This is a ragdoll demo that i have modified to use a box like yours. It appears to work without the choppy motion. Inside there somewhere is your answer

Back to top

Profile PM

hendron

8

Years of Service

User Offline

Joined: 20th Dec 2015

Location:

Posted: 16th Jan 2020 15:12

Link

Thanks blink0k. Unfortunately I'm seeing pretty much the same issue in the demo you linked to. Still getting a slight stutter at a regular time interval. From what I can tell, this only seems to be an issue with the CharacterController. Other physics objects I've tried seem to move as expected.

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 16th Jan 2020 21:21

Link

That's odd. I don't see any stutter at all

Back to top

Profile PM

hendron

8

Years of Service

User Offline

Joined: 20th Dec 2015

Location:

Posted: 16th Jan 2020 23:13 Edited at: 16th Jan 2020 23:16

Link

It's a very subtle stutter, but enough that I can't unsee it. But just to make sure, I took the demo you posted and added a routine to record the distance that the CharacterController moves on the x axis each frame for 120 frames (while only moving right) and then saved the results to a text file. Here's what I got:

0.533325
0.533340
0.533325
0.533340
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533333
0.533337
0.533325
0.533340
0.000000
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.000000
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.000000
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.000000
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340
0.533325
0.533340

+ Code Snippet

Most frames are consistent, but there is a pattern of 0.0 distances every 25 frames.

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 16th Jan 2020 23:32

Link

Why is it so obvious in your example and so subtle in the ragdoll?

Back to top

Profile PM

hendron

8

Years of Service

User Offline

Joined: 20th Dec 2015

Location:

Posted: 16th Jan 2020 23:36 Edited at: 16th Jan 2020 23:46

Link

I have no idea. What's really odd about my example (at least on my system) is that it changes if I move the window. It starts out very, very obvious. But if I move the window, it makes it behave basically the same as your demo. Very strange.

I added the same distance recording routine to my example... here's the result before moving the window:

1.666672
1.599998
1.533333
1.466667
1.400002
1.333336
1.266670
1.199997
1.133339
1.066666
1.000008
0.933327
0.866661
0.800003
0.733322
0.666672
0.599983
0.533333
0.466660
0.400002
0.333328
0.266670
0.199989
0.133339
0.000000
1.666664
1.599998
1.533340
0.000000
1.066666
1.000000
0.933333
0.866666
0.799999
0.733334
0.666667
0.600000
0.533333
0.466666
0.400000
0.333333
0.266666
0.200000
0.133333
0.000000
1.666666
1.600000
1.533331
1.466667
1.400000
1.333334
1.266666
1.199999
1.133331
1.066666
1.000000
0.933332
0.866665
0.799999
0.733334
0.666666
0.599998
0.533333
0.466667
0.400000
0.333332
0.266666
0.200001
0.133333
0.000000
1.666668
1.599998
1.533329
1.466667
1.399998
1.333332
1.266666
1.200001
1.133331
1.066666
1.000000
0.933331
0.866665
0.799999
0.733334
0.666664
0.600002
0.533333
0.466663
0.400002
0.333332
0.266666
0.200001
0.133335
0.000000
1.666664
1.599998
1.533333
1.466663
1.399998
1.333332
1.266666
1.199997
1.133331
1.066666
1.000000
0.933334
0.866669
0.799995
0.733337
0.666664
0.599998
0.533340
0.466660
0.399994
0.333336
0.266670
0.199997
0.133331
0.000000

+ Code Snippet

Very inconsistent.

After moving the window:

0.000000
1.666687
1.666656
1.666687
1.666687
1.666687
1.666687
1.666656
1.666687
1.666687
1.666656
1.666687
1.666687
1.666687
1.666687
1.666656
1.666687
1.666687
1.666656
1.666687
1.666687
1.666687
1.666687
1.666656
1.666687
0.000000
1.666687
1.666656
1.666687
1.666687
1.666687
1.666687
1.666687
1.666687
1.666687
1.666687
1.666687
1.666656
1.666687
1.666687
1.666656
1.666687
1.666687
1.666687
1.666687
1.666687
1.666687
1.666687
1.666687
1.666687
0.000000
1.666656
1.666687
1.666687
1.666656
1.666687
1.666687
1.666687
1.666687
1.666626
1.666687
1.666687
1.666656
1.666687
1.666718
1.666687
1.666687
1.666656
1.666687
1.666687
1.666656
1.666687
1.666687
1.666656
1.666672
1.666626
1.666672
1.666656
1.666656
1.666672
1.666656
1.666656
1.666687
1.666656
1.666656
1.666626
1.666687
1.666656
1.666656
1.666656
1.666656
1.666656
1.666656
1.666656
1.666656
0.000000
1.666656
1.666656
1.666656
1.666656
1.666687
1.666656
1.666656
1.666656
1.666656
1.666656
1.666656
1.666687
1.666656
1.666656
1.666626
1.666656
1.666656
1.666687
1.666656
1.666656
1.666656
1.666687
1.666656
1.666656

+ Code Snippet

The same kind of pattern of 0.0 distances every 25 or so frames.

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 17th Jan 2020 00:09 Edited at: 17th Jan 2020 00:16

Link

Try
#renderer "Basic"

Back to top

Profile PM

hendron

8

Years of Service

User Offline

Joined: 20th Dec 2015

Location:

Posted: 17th Jan 2020 00:57 Edited at: 17th Jan 2020 00:58

Link

Interesting... While it doesn't fix it, it does make it to where it has the 0 distance every 25 frames pattern without having to move the window first. I recorded a video of what I'm experiencing here, in case it's different on other machines.

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 17th Jan 2020 01:26

Link

Yes. Still has that stutter every 25 frames or so. It's very disappointing.
Always finding some glitch or other with 3D physics

Back to top

Profile PM

hendron

8

Years of Service

User Offline

Joined: 20th Dec 2015

Location:

Posted: 17th Jan 2020 01:47

Link

Indeed. I was hoping to use the CharacterController for simple player collisions against a mostly static environment, so I guess I will just have to use a sphere cast setup instead. Thanks for the help though, much appreciated.

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 17th Jan 2020 03:01 Edited at: 17th Jan 2020 03:01

Link

There is a pretty good Non_Physics FPS example here

Back to top

Profile PM

Virtual Nomad

Moderator

18

Years of Service

User Offline

Joined: 14th Dec 2005

Location: SF Bay Area, USA

Posted: 20th Jan 2020 17:39 Edited at: 20th Jan 2020 17:53

Link

Quote: "It's a very subtle stutter ... if I move the window. It starts out very, very obvious."

i recently experienced this when i went to record some 4x footage. it got bad, glitching sound, etc, too.
around the same time, Norton had been popping (wanting to "organize" things) which i closed along with all other applications that i was running and re-booted (i also had a pending windows update in there).
from the vid, you can see that the stuttering/glitching went away (aside from in-game/my fault "stuttering").
ie, i think that other things that were running were interrupting/fighting for attention/resources (which, sometimes, tend to do at regular intervals like you described above).
so, close everything, reboot and see if it helps?

My Itch.io Home.

Back to top

Profile PM Website

hendron

8

Years of Service

User Offline

Joined: 20th Dec 2015

Location:

Posted: 21st Jan 2020 00:37

Link

Thanks Virtual Nomad. I tried that and even tested it on my Macbook and got basically the same results. I haven't noticed the same problem with other physics object types, so it seems to me that this particular issue must be some kind of bug with the Character Controller.

Back to top

Profile PM

fubarpk

Retired Moderator

19

Years of Service

User Offline

Joined: 11th Jan 2005

Playing: AGK is my friend

Posted: 21st Jan 2020 03:00

Link

Create3DPhysicsWorld ( scaleFactor )

have you tried different scale factors

MerryChristmas Everyone
fubarpk on Itch...………...https://fubarpk.itch.io/
fubarpk on googleplay..https://play.google.com/store/apps/developer?id=fubarpk

Back to top

Profile PM Email Website

Stab in the Dark software

Valued Member

21

Years of Service

User Offline

Joined: 12th Dec 2002

Playing: Badges, I don't need no stinkin badges

Posted: 21st Jan 2020 13:32

Link

FYI: The Character controller was not originally designed to work on the static plane.
Try it on a box or terrain.

The coffee is lovely dark and deep,and I have code to write before I sleep.

Back to top

Profile PM Email Website

hendron

8

Years of Service

User Offline

Joined: 20th Dec 2015

Location:

Posted: 21st Jan 2020 17:11

Link

Thanks guys. I tried your suggestions (different scale factors and using a box instead of a static plane), but I'm still getting the same result. Here's an updated snippet that prints out the x-axis move distances over the last 60 frames.

#renderer "Basic"

#constant SW = 1280
#constant SH = 1024

SetWindowSize(SW,SH,0)
SetVirtualResolution(SW,SH)
SetSyncRate(60,0)
SetCameraPosition(1,0,128,-256)
UseNewDefaultFonts(1)
SetPrintSize(15)

ground = CreateObjectBox(1024,1024,1024)
SetObjectPosition(ground,0,-600,0)
SetObjectColor(ground,64,64,64,255)

player = CreateObjectBox(32,64,32)
SetObjectPosition(player,0,32,0)
FixObjectPivot(player)

Create3DPhysicsWorld()
Create3DPhysicsStaticBody(ground)
ovec = CreateVector3(0,32,0)
rvec = CreateVector3(0,0,0)
Create3DPhysicsCharacterController(player,1,ovec,rvec,0.5)

mPrintBuffer as float[60]
mIdx = 0

repeat
	
	oldX# = GetObjectX(player)
	
	Step3DPhysicsWorld()
	
	moveX# = GetObjectX(player) - oldX#

mPrintBuffer.insert(moveX#)
	mPrintBuffer.remove(0)
	
	move# = (GetRawKeyState(68) - GetRawKeyState(65))
	strafe# = (GetRawKeyState(87) - GetRawKeyState(83))
	Move3DPhysicsCharacterController(player,move#,strafe#,100.0) 
	
	Print("Move with WASD")
	Print("")
	Print("X Move Distance:")
	Print("--------------------")
	for i = 59 to 0 step -1
		z$ = ""
		if mPrintBuffer[i] = 0.0 then z$ = "   ZERO"
		print(str(mPrintBuffer[i],2) + z$)
	next i
	Print(ScreenFPS())
	Sync()

until GetRawKeyState(27)

+ Code Snippet

#renderer "Basic"

#constant SW = 1280
#constant SH = 1024


SetWindowSize(SW,SH,0)
SetVirtualResolution(SW,SH)
SetSyncRate(60,0)
SetCameraPosition(1,0,128,-256)
UseNewDefaultFonts(1)
SetPrintSize(15)

ground = CreateObjectBox(1024,1024,1024)
SetObjectPosition(ground,0,-600,0)
SetObjectColor(ground,64,64,64,255)

player = CreateObjectBox(32,64,32)
SetObjectPosition(player,0,32,0)
FixObjectPivot(player)

Create3DPhysicsWorld()
Create3DPhysicsStaticBody(ground)
ovec = CreateVector3(0,32,0)
rvec = CreateVector3(0,0,0)
Create3DPhysicsCharacterController(player,1,ovec,rvec,0.5)

mPrintBuffer as float[60]
mIdx = 0

repeat
	
	oldX# = GetObjectX(player)
	
	Step3DPhysicsWorld()
	
	moveX# = GetObjectX(player) - oldX#

	
	mPrintBuffer.insert(moveX#)
	mPrintBuffer.remove(0)
	
	move# = (GetRawKeyState(68) - GetRawKeyState(65))
	strafe# = (GetRawKeyState(87) - GetRawKeyState(83))
	Move3DPhysicsCharacterController(player,move#,strafe#,100.0) 
	
	Print("Move with WASD")
	Print("")
	Print("X Move Distance:")
	Print("--------------------")
	for i = 59 to 0 step -1
		z$ = ""
		if mPrintBuffer[i] = 0.0 then z$ = "   ZERO"
		print(str(mPrintBuffer[i],2) + z$)
	next i
	Print(ScreenFPS())
	Sync()

until GetRawKeyState(27)

My results:

Attachments

Login to view attachments

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 21st Jan 2020 21:16

Link

Me too

Back to top

Profile PM

Sorry your browser is not supported!

AppGameKit Studio Chat / 3DPhysicsCharacterController -- choppy motion?

Attachments