Same Seed, Different Outcomes

Same Seed, Different Outcomes

Return to topic list

Sun Oct 11 02:26:15 2020   by   Aphroneon
I downloaded the source code and compiled it on my machine and generated maps offline. I also used the web version. When I used the same seed, they came out different. Why is this?

https://imgur.com/gallery/VYpjDwc

The command line inputs appended to the BMP files:

Online: ./planet -S -s 0.7710338 -w 2000 -h 999 -l 0.0 -L 0.0 -m 1.0 -pM -C Olsson.col -i -0.02 -B -n -o Maps/Map-338.bmp

Offline: planet -S -s 0.7710338 -w 2000 -h 999 -l 0.0 -L 0.0 -m 1.0 -pM -C Olsson.col -i -0.02 -B -n -o planet

Other information:

OS: Windows 10 64-bit
Compiler: Clang with -Ofast flag

The choice of compiler and optimization doesn't seem to affect the result. I can't test for OS differences though. Maybe that's why?
 
Mon Oct 12 10:06:05 2020   by   Torben
When I run the offline program with the parameters you indicate, I get the map shown at the top of your gallery (the one you say is done with the online generator). I get the same when I use the online generator (seed 7710338).

So I can't really explain why you get different maps, except if your computer doesn't use the IEEE standard for floating-point numbers, but practically all computers these days do.

 

Return to topic list



New message:
Topic:
Posted by:

Type the values of the dice shown below:

Return to topic list