UNCLE'S SWEATER
Author: rostok (@von_rostock / rostok.itch.io)
Category: Christmas Challenge
System: PICO-8
Language: Lua 5.2 but PICO-8 does not include the Lua standard library.
Len source code: 115
Len exe file: 54
Len code only: 54
Instructions:
1) Emulator (free)
open source.txt in your favourite editor or just use this file
copy the code into clipboard
go to https://www.pico-8-edu.com/
click on the triangle
press Esc to enter editor
press Ctrl+V to paste the code
press Esc again to exit the edior
type RUN(CLS()) to clear the screen and run the code
type this in lowercase
press Enter
wait COUPLE OF HOURS till the star is drawn
2) Actual PICO-8 emulator (propertiary)
follow steps above but instead of opening browser emulator run the app
3) Actual PICO-8 emulator (propertiary), different approach
start the emulator locally
type LOAD VC-2023-14.ROM end press Enter (in lowercase)
type RUN(CLS()) end press Enter
behold
Description:
The code is quite simple really, it loops endlessly generating random
coordinates which are pasted on screen using print shorthand
and with color being adjusted to draw sweater pattern
Here's the code:
x=@24389+3y=@24388run(?"*",x*5.9,y*6.8,8<<(x*x-y*y)%6)
And explanation for unpacked statements
-- assume that user has clear the screen
x=@24389 -- read pico-8 memory that corresponds to
-- internal state of psedo-random number
-- generator. luckyli this is randomized
-- at each program start
-- x value is from 0 to 255
+3 -- add 3 to shift slightly to right
y=@24388 -- also set y to random value (same range)
run( -- here's a bizarre way to loop the program
-- by executing statement in run parameters
?"*",x*5.9,y*6.8, -- print asterisk at scaled coordinates
8<<(x*x-y*y)%6 -- choose the color which is either red (8)
-- or black (2^4 an higher values)
) -- loop ends here
--
-- UNFORTUNATELY DUE TO LARGE RANDOM SPREAD
-- AND DELAY WHEN RE-RUNNING CARTS THIS
-- CODE WILL TAKE HOURS TO RENDER
-- THE PATTERN
Comments:
This archive and source length
------------------------------
source.txt - source without 3 line header
vc-2023-14.p8 - source code with PICO8 header
vc-2012-14.rom - packed PICO-8 ROM
vc-2023-14.png - a screenshot
vc-2023-14-mac.jpg - a screenshot from mac gui
source.png - source screenshot as PICO doesn't wrap lines
As there are 3 files with various length I would like to explain that in
my personal opinion bare source code (54 bytes for this submission)
should be taken for PICO-8 ranking.
PICO-8
------
PICO-8 is a virtual machine that has look and feel of 80s game consoles.
It's screen has a resolution of 128x128 pixels and displays 16 colors.
Memory is limited to 64kb however Lua variables & code are separate and
limited to 2MB. PICO-8 CPU is also limited with each instruction having
a specific number of cycles.
To see some interesting PICO-8 sizecoding creations follow #tweetcart tag
on Twitter. This tag is often associated with a single tweet long code
(280 chars) focused on making various demo effects.
