Let’s say a game file size is 500MB. If there is a 100MB patch, does the file size go to 600MB? Or does it patch what’s needs and deletes the old files?
it depends what that path does, it can add 100 MB of new content, or it can replace a 100 MB file to fix bugs or improve things, or anywhere in between, it could replace a 50 MB file and add 50 MB of new content
My game might have 10 files file1 to file10, and every file is 10 MB. I make a patch which:
1. Adds new content => I need to create a new file11 for the content, 10 MB for that
2. Fixes a bug in some old content => I upload new version of file3, another 10MB
3. Adds cross-functionality with new file11, so I need to upload the main game in file1, another 10MB.
So in total, I will upload 3 files, total of 30MB. However, since two of these files replace old ones, only one is new, the game size goes from 100 MB to 110MB, not 130 MB, since I can delete the old versions of file1 and file3.
This depends on each platform.
PC platforms are installing patches by editing/replacing existing files and adding new ones if necessary.
On game consoles patch as a whole is mounted next to base game when game is launched, it’s not replacing physically installed files. Patch usually for assets doesn’t include whole files, but only changed bits with informations where those changes in original files happened. So when game will want to load texture that was patched, system will read data from both base game for original data and patch for changed data.
The patch doesn’t just replace the small part of code they want to update, I think that’s called a hot fix usually
The patch would replace a lot of old files if its a performance or bug fix patch. If it’s a feature addition or new content then it would increase the size of the install.