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Camera angle performance drop results?
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llynx Offline
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Post: #16
RE: Camera angle performance drop results?
Are you sure this isn't just a shadow draw optimization?
02-17-2011 12:20 AM
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Driklyn Offline
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Post: #17
RE: Camera angle performance drop results?
In my opinion, there isn't anything wrong here. This seems like completely normal behavior to me.

In the first picture, almost all of the shadows are hidden so not much for the shaders to process on that part. In the second, the shadows are fully visible plus there is an extra reflection shown in the terrain from the sun.

There is less to process in the first picture than in the second, so the FPS will be higher. This is true in all games.

For example, run that tutorial again, look straight down and then use the mouse to move the camera away from the terrain so that all you see is a light blue color. The FPS will be ever higher than it was in the first picture. This is because there is less to process. No reflections, no shadows, less bloom, etc...

Call Of Duty: Black Ops is the same way. You will get a higher FPS when looking up into the sky than when you're looking straight ahead.
02-17-2011 12:22 AM
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Harry Offline
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Post: #18
RE: Camera angle performance drop results?
I start this tutorial without shadows and fps drop anyway so it's could be because sun light/highlight and other effects connected with sun have to be processed as Driklyn wrote.
02-17-2011 12:30 AM
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Zervox Offline
Silver Supporter

Post: #19
RE: Camera angle performance drop results?
Ok, tested this on a complete empty world well the performance drop is still there.
and the first screenshot, no the shadows are still being rendered, you just got problems seeing them as its a scaled down screenshot.

That is basic optimization Driklyn, thats called out of view culling, this does not explain a 100 fps drop on rotated angle, and as said it still drops when without those barrels.

and since the shadows are still visible even from the other view I posted I kinda have a problem with taking that as a possible reason, as the shadows are still visible.

@harry, you are right its actually the sun.gfx which sucks performance.
Sun.image=Images("gfx/sky/sun.gfx");
(This post was last modified: 02-17-2011 12:39 AM by Zervox.)
02-17-2011 12:34 AM
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fatcoder Offline
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Post: #20
RE: Camera angle performance drop results?
Yes, I just noticed it has something to do with the sun in this particular example. I can move the camera all over the place and keep a steady fps until the highlight of the sun starts to come in, then it will drop.

I don't have any problem with a drop in performance when more expensive rendering appears on screen. That is normal. What I have a problem with is how it happens. The fps will change in such an uncontrolled manner (often resulting in stuttering) that anything performance sensitive in your world will get a kick in the pants, such as physics related stuff. Physics relies heavily on consistent and smooth performance. If you upset that, you throw the whole system.

@harry, another thing I noticed in a test I ran some time ago (refer to the link in my first post on page 1), was if I applied more than about 3 textures to a given area of the terrain, then that area would suffer from very bad (and random) performance drops, like what we are seeing now. You might want to check this in FV, in your poor performing areas. I know it is hard to only use 3 textures, but if you do have to use more, don’t let more than 3 overlap at all on the terrain. EE hates it.
(This post was last modified: 02-17-2011 12:47 AM by fatcoder.)
02-17-2011 12:41 AM
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Harry Offline
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Post: #21
RE: Camera angle performance drop results?
I turn off shadows in FV as llynx wrote and I gained about 90 fps in the corner of prison and 50 in forest (where probably I have more than 3 textures on area as fatcoder write and lots off grass, mushrooms, trees). So should I make some shadow draw optimization by shdFrac() and shdFade() functions? Or there is another ways do to this?

Btw I checked what happens when I look at sun in FV (with turn off shadows) and I don't have any performance drop...
(This post was last modified: 02-17-2011 01:04 PM by Harry.)
02-17-2011 01:03 PM
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llynx Offline
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Post: #22
RE: Camera angle performance drop results?
I get get a 380 to 220 drop when sun is in the screen.
02-17-2011 01:21 PM
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menajev Offline
Bronze Supporter

Post: #23
RE: Camera angle performance drop results?
If you want really big fps drop just render some particles close to cam.
02-17-2011 05:06 PM
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Dynad Offline
Member

Post: #24
RE: Camera angle performance drop results?
(02-17-2011 05:06 PM)menajev Wrote:  If you want really big fps drop just render some particles close to cam.

Yea i noticed this a lot too while working in the Editor..

There is always evil somewhere, you just have to look for it properly.
(This post was last modified: 02-17-2011 05:17 PM by Dynad.)
02-17-2011 05:17 PM
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Esenthel Offline
Administrator

Post: #25
RE: Camera angle performance drop results?
this is probably caused by Sun Rays effect (which are visible only on certain angle when looking at sun)
02-18-2011 01:30 PM
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