Hi guys/girls

I present you here with a sort of tutorial on how to patch the Ultima Online Client.
To understand everything assembler knowledge is required.

Like most UO addicts will have noticed, the client uses a lot of CPU resources when it shouldn't be doing that, for example at the login screen. This annoyed me and I went inside the client to fix this "bug".

At the same time, you will learn a bit about frame-skipping done by the client (when enabled).

Attached is a PDF that explains how I did it + a ZIP with the patch applied to client version 5.0.8.3.

WARNING! Do not apply this patch to any other client out there unless you know what you are doing, this is a binary patch and modifiying the wrong bit/byte will most probably result in (random) crashes!

For version 5.0.8.3:
MD5 of the original unpatched client : fea4323aec8c71f993aad4af812ab1ed
MD5 of the client with Sleep patch applied : 78a963c0fde2bb935c14c75b688fc3f3

If demand is high enough, I could write a universal patcher that will work for other clients based on the fact they all share the same codebase.

Enjoy

Great post and Mod Batlin, thanks a ton for this!

all i can say is wow, you have to be the smartest person ive seen to be able to do that, that is excellent work, congrats, I for one would like to see a universal patch or could you please make a patch for client 6.0.1.4, that is what I use and find it to be very stable, if not, thanks anyway, and keep on doing what you do, you are obviously very good at that..

thanks

Great!

Could you release a patch even for client 5.0.9.1?

whoot

Is it possible that you can create a universal patch for all the cilent? I am currently using an older cilent...its not green....I think your work saves our earth and prevents global worming . Thank you in advance!

Oh, you are awesome. I am a computer engineering student and I know the hard work and the knowledge it takes to get where you went.
I really appreciate your guide and your patch, since that CPU usage problem is killing many computers. My laptop did shutdown last night due to over-warming.
I am sure many people will love if you do an universal patcher (myself included).
The only question I have in my mind is "Why doesn't OSI implement this?"

PS: Sorry for my english and thanks again for being such a nice guy and share your stuff with everybody

that is what i was looking for years, great! But i can't say i applied it, a universal tool for it will be amazing

Amazing posting thanks!!!!

there is a similar tool to this called uoloader.
anyway, that one doesn't work in win7 x64 system which is the future...

therefor a new universal patcher is necessarry

i'd be highly interessted and some other ppl i know, that are in desperate need of a universal client patcher.

i already tried to patch the exe myself without success
the client is v2.0.3 which is used pretty often on free shards.