freds72 [Lexaloffle Blog Feed]

tline3d incorrect sub-pixel rendering

Thu, 11 Apr 2024 16:38:14 UTC

tline3d misses sub-pixel precision and generate incorrect samples at borders.

note: tline3d adheres to the (correct) rule of filling [x0//1;x1//1[

how to reproduce:

run attached cart
left: per pixel
right: tline3d
notice border artifacts & texture wobbling

satanebika

by freds72

[Click to Play]

vec adds crash

Fri, 05 Apr 2024 18:29:26 UTC

version: 0.1e
Os: Windows 10

How to reproduce:

run following code

a=vec(1,2,3)
b=vec(1,2,3)
print(0.5*(a+b))

picotron crashes to deskop with:

Exception thrown at 0x004A231E in picotron.exe: 0xC0000005: Access violation reading location 0x00000000.

Workaround #1:

a=vec(1,2,3)
b=vec(1,2,3)
print((a+b):mul(0.5))

Workaround #2:

a=vec(1,2,3)
b=vec(1,2,3)
print((a+b) * 0.5)

memmap(addr) crash

Wed, 03 Apr 2024 17:18:44 UTC

Version: 0.1e
Host: Windows 10

How to reproduce:

in the terminal type:

memmap(0x8000)

Picotron crashes

related: how to un-memmap???

incorrect tline3d clipping

Sun, 24 Mar 2024 06:34:54 UTC

How to reproduce:

use tline3d with "w" parameters
draw a tline where the starting point crosses the screen border
notice that result gets skewed

demo cart:

arrows to move square
see what happens when moving left :)

unrelated: tline3d doc needs some carriage returns!

wowogomewe

by freds72

[Click to Play]

message footer truncates long lines

Sat, 23 Mar 2024 12:22:00 UTC

how to reproduce:

create a lua file in a long path
say:
/apps/mygame/program.p64/library/maths/matrix/code.lua
see how syntax errors message get truncated:

time drift (screensaver)

Sat, 23 Mar 2024 11:47:24 UTC

how to reproduce:

select "dizzy.p64" as screensaver
let it run for some minutes
rotation/effect speed increases over time

feature request: mouse lock

Thu, 21 Mar 2024 21:29:37 UTC

Rationale:

sfx buttons would make more sense with a hidden mouse
a couple of projects of mine :)

printh doesn't produce any output

Wed, 20 Mar 2024 19:36:20 UTC

Symptoms:

platform: Windows / Mac?
printh from a program yields nothing in the program output window

How to reproduce:

copy following code in main.lua

printh("bob")

precision: confirmed to work on Linux, text is directed to the console that launched picotron

no print output until _update loop

Wed, 20 Mar 2024 19:33:32 UTC

Symptom:

a program that loops (intentionnaly or not!) will not produce any print before _update or program exits.

How to reproduce:

paste following code in main.lua

for i=1,10 do
 print(string.format("hi world %ith",i))
end

while true do
end

Demi Daggers

Wed, 22 Nov 2023 20:19:24 UTC

Demi Daggers

by freds72

[Click to Play]

Note: game must be played from splore - this page doesn't support mouse lock
Note: global leaderboard not yet available

Take the cursed dagger, use its power to dispatch the horrors from this hellish place, score the best time!

Note: this is not an official Devils Daggers port for PICO8 but a fan game using Sorath's game universe.

How to play

Default controls: ESDF + mouse
Fire: left mouse button
Jump: space

Local stats icons:

number of jewels collected
number of daggers fired
hit ratio
obituary message
session time

Configuration & Settings

Go to Settings , adjust and accept to save your changes.

Online Leaderboard

Game uses Newgrounds leaderboard for competitive play.

Play from until scoresub is available:
https://freds72.itch.io/demi-daggers
https://www.newgrounds.com/portal/view/905300

Click on online - connect button on title screen to login (or create) with your NG account.

Online ladder can be disabled from settings menu.

Editor How to

Game ships with a built-in editor.
Design your own voxel enemies and share your creations on #demidaggers!

(see workaround below for middle click)

Editor 101

*All commands have a tooltip, hover the mouse on the icon and a sliding text will appear:

Mouse bindings:

left click: draw voxel
middle click (hold): rotate view
right click: pick color from cursor
green line: represents the drawing plane (switches dynamically)
mouse wheel: moves drawing plane back&forth (slices)

In case you want to revert to original models, hit P (for pause) and select reset all (needs confirmation).

Saving & Sharing

play command saves the models, generates images and goes back to title

copy copies the current model to the clipboard, easy to share a single model. Don't forget to post the corresponding gif!

Paste the text on the target model to use it.

export saves all models for sharing

When running standalone (binaries or PICO8 desktop), file is located under

%APPDATA%\pico-8\appdata\freds72_daggers\export.p8l

When running on web, use browser dev tools to extract the "freds72_daggers_asssets.p8l" file.

Drag&drop an export.p8l file over an open editor to replace your current voxel collection.

Credits

Sorath: original game!
Ridgek: (awesome) music & sound design
Artyom Brullov: additional gfx (thanks!)
Heracleum: cover art
Werxyz, Miss Mouse: beta testers
Zep and the #pico8 discord folks!

Post-mortem & Technical Details

See: https://freds72.itch.io/demi-daggers/devlog/638738/journey-to-demi-daggers

Changelog

V1.3 (15064e3)

changed: removed multi-spritesheet exploit with new Pico 0.2.6 version
changed: covert art by Heracleum

V1.2 (8f696d9)

changed: improved egg model (re-generate via editor)
changed: squid spawn no longer invicible before spewing
changed: reduced shotgun duration (3 frames)
changed: reduced worm difficulty
changed: Increase spawn & chatter spider sfx loudness
changed: lower streak wait time
changed: high level shotgun fire over several frames
changed: large centipede health
changed: increased skull gravity
fixed: improved shotgun cpu usage
fixed: prevent chatter from not playing back after Ctrl+R reload
changed: reduced skulls upward speed
changed: improved squid hitbox
added: auto gif option for best score>30s
changed: attract cooldown for shotgun
changed: build version in settings menu
fixed: crash in editor for bad colors
fixed: high cpu switching menu in title
fixed: skulls fountain on title
fixed: removed invalid color in editor

V1.1 (164e498)

changed: shotgun on "long" click
change: upward move on squid spawns
fixed: smooth "coyotte" move
fixed: jump on press
fixed: removed browser mouse acceleration
fixed: editor not going back to title
fixed: editor crash on last color

reload disregards source cart size

Fri, 17 Nov 2023 18:24:45 UTC

How to reproduce:

save a zero length pico8 file

cstore(0,0,0,"blah.p8")

reload() file from another cart

reload(0x0,0x0,0x4300,"blah.p8")

surprise! 0x0 -- 0x42ff was been wiped out clean even if "blah.p8" doesn't contain any data :/

Mouse lock drift on Firefox

Sun, 05 Nov 2023 15:15:42 UTC

Symptoms: the mouse drifts right on Firefox (only)

How to reproduce:

export demo cart as an html page
publish page on itch.io (or equivalent)
run game on Firefox (MacOS or Windows - Linux is fine)
notice mouse x-drifting

Note: does not occur when game is run locally
Note: does not occur when game is run fullscreen using the Pico8 button
Wild guess: suspect a Firefox bug regarding mouse coordinates and iframes?

Test cart:

https://freds72.itch.io/mouse-lock-test
password: mouse

Code:

function _init()
 poke(0x5f2d,0x5)
end

_x,_y=0,0
function _update()
 _x=mid(_x+stat(38),0,127)
 _y=mid(_y+stat(39),0,127)
end

function _draw()
 cls()
 print(_x.."/".._y,2,2,7)

 circfill(_x,_y,4,8)
end

Invalid pre-processing of ternary

Fri, 30 Jun 2023 19:46:49 UTC

How to reproduce

execute code:

print("a")
(nil or print)("b")

outputs:

A
runtime error line 1 tab 0
print("a")
attempt to call a number value
at line 1 (tab 0)

note that print("a") is correctly executed regardless of the error being reported on that line!

Workaround

print("a")
local fn=nil or print
fn("b")

cstore() to p8.rom filename saves png

Sun, 05 Feb 2023 13:32:46 UTC

Expected:

-- save to p8.rom format
cstore(0,0,0x4300,"test.p8.rom")

Outcome (bug): test.p8.rom is actually a png file!!

0.2.5d _env syntax error

Tue, 13 Dec 2022 19:27:36 UTC

The _env (lower case) keyword is no longer supported:

example cart: https://www.lexaloffle.com/bbs/?tid=48907

likely a general bugs on upper/lower case remapping.

some p8scii string won't copy to clipboard

Sat, 20 Aug 2022 13:38:10 UTC

Marking as resolved - this is a "feature" of printh to stop at \0.
Solution to export p8scii to clipboard is given here: https://www.lexaloffle.com/bbs/?tid=38692

Repro cart:

haguramako

by freds72

[Click to Play]

Outcome:

p8scii correctly copies bytes on screen
bug: clipboard gets only a truncated command (should be 612 chars)

Note: works as expected if background is not 0

inconsistent poke 0x5f56 rules

Thu, 16 Dec 2021 07:51:26 UTC

The new poke to set map start cannot be applied to 0x20.
eg:

— does nothing :[
poke(0x5f56, 0x24)

for small maps, the 0x2000 ‘hardware’ map area cannot be reached in full:

— hw map
poke(0x5f56, 0x20)
— say tiles are starting after a large 32x32 map
— set width
poke(0x5f57, 2)
— yikes, cannot set y offset (>256)
poke(0x5f3b, 32*32\2)

Totally Accurate Holiday Bowling

Tue, 14 Dec 2021 06:16:11 UTC

Holiday season, stuck at home waiting to open presents?
Despair snow more, a play of totally accurate bowling will enjoy the day!

freds72_bowling

by freds72

[Click to Play]

Devlog

Codebase expands from Ghost Rally, no longer limited to a single dynamic/static response.
Collision hulls are limited to solid rectangles to benefit from simplified overlapping tests and clipping maths.
The whole engine could be plugged into any 3d engine if you don't mind the staggering token cost :/

Sources are available at: https://github.com/freds72/chamboultout

The game went through multiple iterations (initial idea was a "chamboultout"), including odd things like:

or a "Santa Bombers"!