Cheat Engine

pox911

This is driving me nuts. I'm probably over looking something but im having trouble with a compare.

Basicly i have my value at X and the compare is at [X+8]+10. What i did was push ecx, store [x+8] in ecx, then compare [ecx+10] to my value.

Whats wierd is that it causes a crash. I have the pop where it needs to be.

if i have it as "cmp ecx,5" it wont crash but "cmp [ecx+10],5" causes a crash. Any idea as to what im over looking?

daspamer · Posted: Wed Jul 24, 2013 6:55 pm Post subject:

Sometimes the pointer does not exist?
I faced this issue.
So basically before touching the pointer, check if its valid.

pox911 · Posted: Wed Jul 24, 2013 6:59 pm Post subject:

still crashes

Edit: This is the asm i have for what doesnt crash.

Gniarf · Posted: Wed Jul 24, 2013 7:09 pm Post subject:

Same line of thought than DaSpamer, just handles more cases than just null pointers.

pox911 · Posted: Wed Jul 24, 2013 7:38 pm Post subject:

unless i did something wrong, it still crashed the game.

I'm still learning assembly so i still dont understand the lea command and how Test compares to the cmp command.

Edit: As a cheap work around i currently have an aob for where the pointer points to and if the address matches up it will do its jump.

Gniarf · Posted: Wed Jul 24, 2013 7:48 pm Post subject:

Does my script still crash if you comment the cmp dword [ecx],5 .

As for lea and test:
lea ecx,[ecx+10] is like add ecx,10 or ecx=ecx+10.
test eax,eax is like cmp eax,0 except that I don't think ja/jb/jl/jg won't work after a test. Compilers (almost?) always use test eax,eax to see if eax is 0.

pox911 · Posted: Thu Jul 25, 2013 10:24 am Post subject:

I could have just messed up the scirpt after the compare.

Im trying to understand the call IsBadReadPtr better. I thinki understand the push ad since i have to use the same thing when using the function for button presses. Im guessing the push 4 is the length and one of the push ecx is to tell the function what value to check?

mgr.inz.Player · Posted: Thu Jul 25, 2013 12:33 pm Post subject:

pox911 · Posted: Mon Jul 29, 2013 7:22 pm Post subject:

I still dont fully understand.

i think i understand the lea now but why are you running it twice? It works when done that way but failed if only seen once. why is that?

Edit: This value effects a lot(health, ammo, the works). If im comparing 2 values before a jump, what is the best way to do that?

Curently its just a jne to the next compare, if it passes then it checks the next one and if that fails it goes to default code.

mgr.inz.Player · Posted: Tue Jul 30, 2013 2:53 am Post subject: