Confused about rounding error

Sun, 31 May 2020 19:30:29 UTC

Hi, I'm confused about the following. In my platformer game I apply a 0.85 factor to dx as friction. When I do this on a negative dx value (i.e. player moving to the left) dx never reaches zero and is represented as -0 (minus zero).

When I use that dx value by adding it to x, the x value keeps counting down a tiny fraction on every update.

I can work around it of course (e.g. setting it to 0 when abs(dx) is smaller than 0.0002), but I'd love to understand what's actually happening here. All pointers are appreciated :)

You can see it in action here:

yipobarode

by 56bitsago

[Click to Play]

Switch Macbook to sleep with Joystick connected: cURL metrics + segfault

Fri, 24 Apr 2020 08:03:09 UTC

When I let my Macbook (Catalina 10.15.4) sleep while having a joystick (8BitDo SN30 Pro+) connected PICO-8 segfaults, and outputs some cURL transfer metrics just before that:

[127,14]   set sprite: 0
[127,15]   set sprite: 0
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  177k    0  177k    0     0  99737      0 --:--:--  0:00:01 --:--:-- 99682
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
100 41674    0 41674    0     0  77750      0 --:--:-- --:--:-- --:--:-- 77750
Segmentation fault: 11

(Note: first two lines are debug output from my cart).

Does anyone know why PICO-8 does a cURL call actually? Does it auto-report bugs or perhaps it checks for new versions?

56bitsago [Lexaloffle Blog Feed]

Confused about rounding error

Switch Macbook to sleep with Joystick connected: cURL metrics + segfault