Hi

There are currently two ways of HD patching a title:

[1] The conventional way  

 As mentioned above - load all the data into the upper part of memory, patch the loader to copy it from there instead of going to disk, and let the game run in the lower part of memory - so for these you will requires 512k+size of all data (packed)+say 2k for patching routines.   This is the way most things are done to fix for HD.  The down side to this is that ALL I/O has to be killed, which means no high score saves or savepoints.

[2] Universal Loading System [ULS] conversion

 This is our stubloader code that is basically our version of WHDLoad on the Amiga (But works in a completely different way!)  The Atari's O/S is given its own "virtual environment" to run in and is swapped in and out every time an I/O request is needed.  These patches will all need at least 1Mb ram to provide the O/S the environment it needs to run in, alongside the memory that the game will use.

  ULS is currently *not* my prefered method for patching as it eats memory and causes slower loading than RAMdisking titles. However it is the only way to have a true HD-save game or high score save version, so it still has its uses.

 It is currently under development to give it full functionality on the Falcon using the PMMU to provide the game title with the virtual RAM, instead of the O/S running virtually, which will make it a lot more useful and stable - but thats a long while off and will require motivation ;-)

 We are also playing with a 3rd option which would allow any .msa disk image to be mounted and booted directly from an Atari HD - even titles doing direct disk access work using this method.  As we have stated many times previously, this is still a long way from being released, but it has been lab tested ;-)  Some working titles for this project are:  "ImpossiLoad", "NotImgRunner" and "ItJustWorks"

 Just for information, version 0.0001 of U.L.S. was called TOSoff (Because you can load with TOS disabled) - but Showaddywaddy made me rename it.  I still don't know why....

 Hope this helps answer your shy friends questions :-)