4 replies to this topic

[SpreeTree]

I have been having a problem which I am having trouble seeing though, so I am throwing it out here to see if any of you have encountered this before.

The application is written in C++ with DirectX 9 (June 2005 update).

My dev machine has a GeForce 4, and my secondary machine is a poor laptop with an Intel card. My current project is getting a decent frame rate (~140fps) on my GeForce PC, and decent(ish) fps on the laptop.

Unfortunately, when run on a Radeon based PC (Radeon 9700 and 9800 Pro), the frame rate drops significantly (were talking dropping to about 15-10 fps). Unfortunately, I can’t debug on this machine (its a friends machine, at work, and he lives on the other side of the country... Debugging across MSN is not pleasant).

I know due to the limited profiling I can do that it is without doubt in the drawing code, and more specifically, it seems to be the alpha based drawing code, and even more specifically (but I’m not so sure about this bit) the colour keying draw code.

I have checked that the device state is correct (using ValidateDevice(…)) and so I’m pretty sure I have set everything up correctly. All I can assume is that when creating the index buffer I’m missing something out that might be Radeon specific.

I’m rendering the primitives using DrawIndexed primitive, using triangle lists.

Has anyone experienced anything like this before? If you have, any advice would be more than appreciated.

Thanks.

[bladder]

Does it happen only with this one application or are other applications behaving in the same way? If your app is not the only one that behaves like this then it's safe to say that it's a driver issue - nothing you can do except rollback to an old driver, or get an updated one for your friends machine. But make sure the apps you try use similar functionality - in this case color keying.

Something you can try is turning off alpha testing and just leaving in alpha blending and see if that helps.

This happend to me once before as well, it turne dout to be a driver issue. I updated the driver and it worked fine after that.

[bladder]

I'm curious, what happened with this?? You work anything out SpreeTree?

[Led]

Just some random remarks, but have you made sure that
a) your friend is using the latest videocard drivers
b) your friend has installed the drivers for his mobo-chipset (especially important for VIA chipsets).
c) your friend is using the release-version of the DX-runtime (if he's a developer too, it might be switched to debug-mode)

just my $0.02

[SpreeTree]

bladder said:

I'm curious, what happened with this?? You work anything out SpreeTree?

Err... I just saw this response... Sorry for the late reply!

It did work itself out in the end. It was happening on two machines with Radeon cards, but not another, also with a Radeon card. The only difference between the machines was that the machine that was fine has XP Service Pack 2 installed.

My friend installed Service Pack 2 onto both his machines and the game started to work fine. Obviously, I now have no machine with a Radeon card using original XP, so I can't test for it...

So, I didn't fix anything... And the problem is probably still there, but I'm living with it for now and hoefully picking up a Radeon card sometime soon(ish). That way I can sit at home and actually figure out the problem hopefully!

Again, sorry I didn't see your reply!
Spree