Wizard of Wor "un-hackable?"

[dr. kwack]

I'm trying to do a "Wizard of Wor Arcade" hack, and I'm finding that changing the monsters causes untouched sprites to scramble a bit. Has anyone else encountered this?

[Nukey Shay]

Question: are you altering ONLY non-zero values? Do you have a list of addresses you've changed?

[dr. kwack]

Well, here's my opportunity to show just how green I am.

 

I can tell you that I worked on the program thru Hack-O-Matic and that's about it. I scanned the BIN file looking for the graphics (as per usual) and made my changes.

 

I know I did not change any non-graphics stuff, if that's what you mean. I couldn't remember if W.O.W. was one of CBS's RAM Chip games or not.

[Nukey Shay]

No, what I am saying is that it's not always possible to make sprites bigger or smaller. You'd have to disassemble the game to be sure. As long as you only change bytes that contain pixels to other non-zero values, it should work (though this could also fail if the game uses a particular value to determine where sprite "delimiters" exist...some programs just use the value of $00 - no pixels - to signify that line is the end of the sprite).

[dr. kwack]

Ahhh! Gotchya! Yeah, as a matter of fact I did go beyond the limits of the original sprite! I expanded it to add more detail.

 

Should be common sense stuff!

 

Thanks!

[Nukey Shay]

Most programs don't use delimiters, though..but just read the sprite data from specific locations. So most sprites you can change to be smaller than the original...because the program itself has instructions like "gather the values from THIS rom location and put the data on the screen". It's usually only when you try to go larger that you run into problems.

[StanJr]

true, Nukey but it seems to me some programs read the data in sequence and if you shrink the sprite from the top down it may not show up at all because there is no data for the first address and it just skips the rest. Had that happen to me at least once.