I’m following the official tutorial here - Time Attack Racer with Blueprints (pre. v4.8) - YouTube - to make a timer for my project (in Unreal Engine 4.5), and all I’ve done is add a timeline in my character with a float in it, and tried to set it to 60, but it keeps changing to 60.000004, even after compiling/saving/recreating a new timeline. When I try to set any value to 30 within it, it changes to 30.000002, 50 changes to 50.000004, 55.5 changes to 55.500004, I have no idea what is doing this or how it can even work like this. 34 works as 34.0, and various other numbers do work, but some change like above. Is this a bug with the actual engine, or? I’d really appreciate some answers to this very confusing and frustrating issue.
Thank you for the response, however that can’t be the problem as in the video tutorial he sets it to 60.0 without any trouble.
It’s in the timeline. I type the number, press enter and it immediately changes the value - http://puu.sh/cgMdW/5d7d4955fb.png
I could be wrong here so someone can correct me if they have a better understanding of why this happens. I think this has to do with the way a float is actually calculated using binary digits, it’s actually an equation that uses scientific notation to approximate a value. Because this equation uses 2 to a certain power, sometimes some exact values aren’t possible to calculate and you end up with a really really close approximation such as the numbers you’ve listed. I could be wrong, but I think the issue is with the data type (a float is only 32 bits, so only so many numbers are possible to be calculated), and it’s not an issue with the engine. I’d read into floating point numbers on Wikipedia or elsewhere if you want to learn more. Is this interfering with your work in any way or it just concerning you to see approximate values?
Can you post a screenshot of where you’re seeing the number displayed incorrectly? Is it in your UI, a print message, the editor interface, or… where is the number looking wrong?
What version are you using? I just tested this and mine works fine, but, I can see that mine looks different than yours.
As mentioned in the post - 4.5 (via the client, not github)
No worries at all. Thankfully this doesn’t necessarily effect my current project because I’m converting that float to an int, however I can imagine any other situation could easily break or require unnecessary workarounds because of it. Wanted to try and check that it wasn’t some strange quirk or something before reporting it as a bug as I didn’t understand how it could break like this and was hoping it wasn’t one but I’ll be sure to do that if no better resolution comes up. Thanks for your help and time :).
Oh I apologize for not seeing that. Mine is normal in 4.4.3 via github. I don’t have 4.5 to test it yet. I would consider reopening this as a bug report if no one answers in the next few days. For now It shouldn’t affect your game, right?