Cheat Engine

relentlesstech · Posted: Thu Jan 17, 2019 8:15 am Post subject: What type is this value REALLY???

Game: Wreckfest (x64)

I am trying to create a 'no damage' script, but the value I am finding for my health is a 4-byte value (Example: 1183749098) - However, once found, and switched to 'float', the value would be a more 'normal' value (Example: 3050.211) - My question are:

1. What kind of conversion is being done to the value from 4-byte to float?

2. How can I create a custom scan type to find these values?

Thank you in advance!

OldCheatEngineUser · Jul 26, 2020

1. no conversion is done, this is how you tell cheat engine to read the value in order to display it.
however, single/double precision floating point values are encoded differently.

2. you dont need a custom scan type, just change the "value type" to float and start scanning.

relentlesstech · Posted: Thu Jan 17, 2019 9:12 am Post subject:

Let me word this differently - If I search for 'health' via changed/unchanged as a float, none of the results I get are my actual health - The only way I can find it is by doing a 4-byte scan changed/unchanged, then it shows up in the list - Once I add it to my address list, and change to float, the value is 'readable' - This only started being an issue after the latest game update three days ago.

As for no conversion occurring, two lines up from where the actual health value changes, is this:

ParkourPenguin · Posted: Thu Jan 17, 2019 9:36 am Post subject:

OldCheatEngineUser · Jul 26, 2020

yes correct, but it do covert packed DWORD to packed single-precision floating point.

one thing to note here:
1183749098 is not 3050.211

relentlesstech · Posted: Thu Jan 17, 2019 11:51 am Post subject:

It took me a while to find the health value again (Could not find a pointer that worked consistently) - The 4-byte health value is '1142292480', which is egual to '600' as float - Searching for '600' as a float value does not list the correct address ...

Here is the disassembly screenshot (Highlighted line is where health is changed):

OldCheatEngineUser · Jul 26, 2020

are you sure you are searching properly? because float 600.00 is equal to 1142292480 in base10 form. (so its already encoded)

and i bet you cant search for 600 as 4 bytes, because (as it appears) value is kept inside xmm registers (whether a conversion is made or not) and probably the game reads it as float as well.

relentlesstech · Posted: Thu Jan 17, 2019 1:33 pm Post subject:

Interestingly enough, I just downgraded to CE v6.8.1, and in 7 scans I had the correct addresses as float - I'm wondering if it was just a glitch in the new version o.O

ParkourPenguin · Posted: Thu Jan 17, 2019 1:49 pm Post subject:

The cvtdq2ps instruction is unrelated- xmm0 gets overwritten by the read from the address.

(float)600 reinterpreted as an int is 1142292480.

This works perfectly fine for me using CE 6.8.2. I still think you didn't do the scans properly. Perhaps a rounding error, lag between GUI and value updates, or discrepancies in memory scan options.