Huge performance drop -> UDK March 2012

[spyzor]

Hello everyone,


Like in the title, I'm experiencing a huge performance drop with not sot much on the display. I'm testing on an iPad 1

So basicaly I'm doing a shooter with a top down view.

I tested also the game just by changing the gametype (so my code is not used) and I still have the issue.



Ok so in the game I have no background at the moment but each time I try to add something there is a huge drop of fps when it's been displayed.

For example I made a simple shader with only diffuse, nothing else but it's a quite large BSP. When I'm over it the fps are low, but when I move away where there is no bsp just my ship then the fps are just fine.

Another test I made is to make a smaller BSP (like 5/6 times the ship), if there is the default shader no problem, but when I put a shader with some transparency (additive or alphacomposite) I have the fps drop.

I also made some test just by exporting a plane out of max and give him a material in additive but I had the same issue. I think as soon as it's "big" I have the fps drop.




Previously I made an app where we were able to visit a loft and I had a lot more textures and assets but everything was in a quite small world.

I started the scene with a default scene provided with udk but removed the fog, the skydome and some other feature to have the less possible activated.


Anybody have an idea what I might do wrong?

[MrRipGames]

Hi,

Do you have activated "Gamma Correction" in World Properties ?
BSP= decreased performance. Prefer staticmeshes (right click on your BSP and convert to staticmeshe)
And limit the draw calls.

An screenshot of your scene is an good idea for understand the possible problem

[XilenceX]

There will be a performance drop when you add BSPs no matter what version of UDK u use.

[Pegasus Programmer]

Another test I made is to make a smaller BSP (like 5/6 times the ship), if there is the default shader no problem, but when I put a shader with some transparency (additive or alphacomposite) I have the fps drop.

Transparency / Translucency is always more expensive. The thing behind the translucent object has to be drawn instead of being culled out so thats one piece of your puzzle.

The problem now is that your description is really vague and hard for any one to answer.

Here are some queries as I was reading and some suggestions:

1) You mention "March 2012" have you tested with earlier versions and compare? If not, yr title sounds like it has something to do with the Mar version and not earlier ones.
2) Best if you post pictures. I do not know how complex the "thing" you are trying to add is, nor how much "huge drop of fps" is. Care to provide stats?
3) I haven't seen the "app" you made, so screens will be nice. If its yr past app was a small world, chances that your objects are not being rendered all at once and most of them culled, so a high FPS is not surprising.
4) Have you considered importing your previous / assets into the March udk 2012 and tried collecting FPS stats and compare?

Hope they are helpful. Sorry if any of them are offensive. I just felt we need more info to know fully what's going on in yr project.

[spyzor]

Sorry but I didn't had the iPad since my last post and after I was finishing integrating the weapon system.

So, I'm back at the performance issue.

Here is one screenshot:


The background is a plane (staticmesh) at first the material was in additive but I also tested it as opaque (with just a diffuse) and there is still the performance drop.
For information I tried several texture resolution 1024, 512 and 256. RIght now it's 256 and it really doesn't look good .

If I move away I get all the fps back even with some other ships running after me.

Here another screenshot:

The top material is actually a swf that I applied as a test with Scaleform... It's why there is transparency where there is no texture.



I tried to display the stats but on the computer there is no FPS drop I nearly see some stats changing.
When I test the game on the iPad it's already lagging just with the stats so I can't see why it's sudenly laggy.
At first it was a BSP Cube, I then converted it into a staticmesh (after reanding the comments here). I gained some fps but it's still laggy when I display it.


I didn't test the assets on another build but as they are pretty simple (a cube and a plane) I'm not sure what might be the problem here.
The only thing I see is that when the object seems to big on the screen there is some lag when it's displayed.

I just tested the same plane as in picture one but really scaled down (it's doing maybe twice the ship size) and now it's running smoothly...


Edit:
Ooook so after a few test with the exact same plane.
Having several same planes but with a small size are better than having one huge plane.



Is this normal?

If I look Epic Citadel I think there is some "huge" asset too and they don't any problem rendering...

[Dragon666]

Are you by any chance having a HUGE open space not limited by anything not even in the farthest distance?
Try putting something like a sky dome, only put some stars on it, that might help.
Also, instead of making the world big, make the ships and the asteroids small.
UDK is not meant for huge open spaces if I'm not mistaken.

[Pegasus Programmer]

Are you by any chance having a HUGE open space not limited by anything not even in the farthest distance?
Try putting something like a sky dome, only put some stars on it, that might help.
Also, instead of making the world big, make the ships and the asteroids small.
UDK is not meant for huge open spaces if I'm not mistaken.

He's actually saying that the background static mesh causes problems, not the ships nor the asteroids, am I right Spyzor?
UDK isn't meant for huge open spaces, however that is true if there are things to render in the first place.

His scene looks pretty empty so....

Spyzor, do you mean you have the default levels + ships + 1 big static mesh with texture on it, it will lag? Are u sure there isn't other stuff in your level?

[spyzor]

Yep, that's the background static plane which causes problems.

I removed the skydome but I will try to put another one. There is no limit to the world right now but there is not so much in it also.
I tried pre computed visibility but as the world is empty except in the middle there is nothing to gain with it...

And only if the scale is big (it doens't mather if I had some definition to the plane or not).
The ships themself are pretty small by the way. If I just put one in the default map the ship si as large as I am.

Also right now there is no asteroids .



Yes I have the default levels + ships + 1 plane as brackground (which is kind of big as you can see in the picture but not really so big...) and there is lag. As I explained with the last screenshot just resize the same plane make the game playable.




Edit:

Ok I just tested with a skydome and the same material I putted on the plane and the result is the same as if I have the big plane displayed.
I'm at 10fps.
Really don't know why it happend...

[spyzor]

Ok, I don't know if it's related but I did some test...


The Epic Citadel don't work anymore.

I tried the Epic Citadel map from the march editor and it's really laggy, it doesn't work like before and I have the same result with the Simple Courtyard map...
So I think there is a performance problem related to the UDK version...

Would be great if someone from Epic could see this post.

[spyzor]

Anyone with an ipad to test epic citadel or both mobile map included with the editor?

[paradoc]

have you tested different lighting models? by disabling all of the dynamic lighting or setting your actors to not receive dynamic lighting, things speed up.

[spyzor]

I only have one Dominant light.

When I test the map without my gametype I don't have any dynamic ship spawned (so no dynamic lighting to calculate) and either without this the fps are pretty low when I look at the skydome.

For the skydome I removed almost every checkbox to remove the collision and the lighting settings...


I also tested to create a new map from blank (without using a preset map) but the problem stays the same...

[Davision]

I only have one Dominant light.

When I test the map without my gametype I don't have any dynamic ship spawned (so no dynamic lighting to calculate) and either without this the fps are pretty low when I look at the skydome.

For the skydome I removed almost every checkbox to remove the collision and the lighting settings...


I also tested to create a new map from blank (without using a preset map) but the problem stays the same...

So from your tests its basically huge object of any type that make the performance dramatically worse? What is when you are really close to such a huge object? Maybe it has something to do with something like camera render distance, some kind of weird bug? Will make a test with my game too, if getting rid of the huge objects will improve performance for me.
I tested epic citadel performance in march udk and previous versions, performance hasnt changed for me. Its average as usual with some lags on 4th gen. The performance from september UDK to october UDK got worse though.

[spyzor]

Yep, for me it's only the size of a mesh which reduce the performance since the same mesh really smaller will increase the fps.

Keep me informed of your test


Another simple test is to just upload the default map with or without skydome to see the fps increase (after removing the fog and the gamma correction of course...).

[AaronJones]

Hey guys, sorry about the perf drop. I believe we fixed up some issues certain people were experiencing and you should see much better performance in the next UDK build! Thanks for your patience on this.

[Davision]

Hey guys, sorry about the perf drop. I believe we fixed up some issues certain people were experiencing and you should see much better performance in the next UDK build! Thanks for your patience on this.

much better performance sounds great!

[spyzor]

Ahhhhhh

The comment I was secretly dreaming of !
Great news just need to wait the next UDK.

[Davision]

Hey guys, sorry about the perf drop. I believe we fixed up some issues certain people were experiencing and you should see much better performance in the next UDK build! Thanks for your patience on this.

The performance in not improved with the new May UDK, not with my game nor with the citadel demo!
Or does anyone else see something improved?

[spyzor]

For me yes.

With march I have more or less 25 fps (without a background), the exact same map with May I have 40 fps.
If I add a skydome then just remove 10 fps like before but at 28 / 33 fps it's still playable.

So for me huge gain of performance.


I think that 10 fps for a skydome is a lot but since it's playable I'm ok with it, maybe there is still something to work there...

[Davision]

For me yes.

With march I have more or less 25 fps (without a background), the exact same map with May I have 40 fps.
If I add a skydome then just remove 10 fps like before but at 28 / 33 fps it's still playable.

So for me huge gain of performance.


I think that 10 fps for a skydome is a lot but since it's playable I'm ok with it, maybe there is still something to work there...

A stupid skydome really shouldnt take 10 fps! lol

I made some tests now with the startup scene with the cube and skydome, fog and gamma correction set off, tested with a ipod 4th gen and shipping settings:
May UDK:
looking at cube: 56fps looking up: 51fps

March UDK:
looking at cube: 50fps looking up: 47fps

October UDK:
looking at cube: 60fps looking up: 60fps!

So October > May > March!

Im seriously wondering how they managed to mess it up so that this very simple scene isnt max fps anymore!?

[AaronJones]

Make sure the skydome is optimized for mobile -- mobile shaders set up and make sure it's not rendering shadows or anything dynamic.

[Blade[UG]]

Have you restarted the iPad ? Epic Citadel runs at 60fps on my iPad 2, I don't have a 1 to test against. It runs about 25fps on my iTouch

[Davision]

Make sure the skydome is optimized for mobile -- mobile shaders set up and make sure it's not rendering shadows or anything dynamic.

If a mobile shader is not setup it will default to a simple mobile shader with the checker texture, i also dont see how dynamic shadows could be possible on a ipad1 or ipod4. Its also the skydome of the startup scene and in the citadel demo that takes the performance!

Im still wondering if there will ever be a performance improvement in one of the many engine releases!? I mean something more then just improving the performance drop of the previous UDK? Or is it just naive to think where it never got improved in the last 16 releases i used?

[spyzor]

Make sure the skydome is optimized for mobile -- mobile shaders set up and make sure it's not rendering shadows or anything dynamic.

I'm only using a skydome mesh I found in Unreal Package with a simple mobile shader I created (with just a diffuse as a base texture).

I have the exact same result with a big plane.


If I scale down the skydome or the plane I get my fps back.

[AaronJones]

I'm currently setting up a grid of builds on various devices to get a complete baseline of performance. I'm using the default cube map that you see when you open up the editor. If I see a red flag anywhere, I'll definitely escalate the issue and work with you guys. Give me a little time, since a lot of this is during my free time. Again, sorry some of you are having issues -- it's bit difficult to narrow down these issues especially when only certain people are having them. It would be easier if I had your device and computer next to me .

[Archerx]

Thanks Aaron! That's really awesome of you to do that.

[spyzor]

Thank you Aaron, just so you know I'm using an iPad first version.

[Blade[UG]]

Aaron,

It seems that iPad 1 is probably the likeliest target for seeing performance issues easily -- the large display coupled with lackluster video and cpu hardware makes it easy to work with and difficult to optimize for. But you probably already know that Having access to only an iTouch 4 and a iPad 2, has made for some interesting issues when faced with test people that mostly have iPad 1s.