Is there anyway on the ti-84 to costom make a backround image for the homescreen?
i got the idea while reading the irc...

Hmmm do you mean have it when you boot up the calc?  Or like its always there when you are typing and you cant get rid of it at all?

EDIT: Ninja'ed with a more competent response

You have to do it in ASM.  Look here:
http://www.ticalc.org/archives/files/fileinfo/168/16870.html

I don't have much experience with hooks, but wikiti can be useful here.
For those and interrupts that stay alive after the setup program ends (it might have to be an app, I'm unsure), you'll definitely have to write it in ASM. (Especially because drawing the image will involve writing directly to the LCD)
AFAIK, a hook is just a routine the OS calls before it does a certain thing, like get a key, for example. These are pretty simple to set up (writing somewhere in RAM or maybe a bcall)
As for the interrupts, yeah, you'll probably end up with a hook (especially if it's an app). But if it's a program, then the basic idea is to use some saferam (like appbackupscreen or statvars) to store the code for handling the interrupt and most likely for the entire routine as well.

Let's say you found this really awesome pic and want it to be the background of your calc during the normal TiOS routines like solving math problems, or graphing equations?
Wouldn't it be cool if there was a program to display on of the Pic vars in the background of calculations and stuff in grey (3 level greyscale), so the normal black and white would be used as normal?
Is this possible?
I think it is, but it would have to be in Asm.  Can someone try this?   Thanks for learning of my idea.

Here's a mock up of what it could look like:

there was. i think an ASM-er said it would have to be written as a hook.

I'd love to this happen
Maybe you can base it off of this program?
http://www.ticalc.org/archives/files/fileinfo/168/16870.html
(And yes, source is included - the file is a Z80 itself.)

I feel like there was a topic started by someone else who had this same idea...let me see if I can find it.

Edit:
Ah yes, it's not exactly the same I guess but very similar. Here it is.

I seriously thought this was a necropost to that topic

Anyway, wouldn't it be slow to have such a large pic being alternated while someone's also using the home screen, though? Especially with OS 2.53MP

EDIT: meishe91, I think that was one of the 1000 Signs