Slow Rush Games

Porting, Performance and Playback

2026-04-10T00:00:00+00:00

It has been a hot minute since my last update, hasn't it?

In my defense, I have been neck deep in tedious engine work.

We'll cover that briefly, but let's also talk about something more GIF-friendly: time traveling!

Making Drop In Multiplayer Easy

2026-02-27T00:00:00+00:00

Signs of Danger has both online and local co-op.
Remote players are controlled remotely (duh), but I gotta support multiple gamepads for local players, with an easy drop-in/drop-out flow.
Still, when playing singleplayer, you should be able to seamlessly swap between keyboard & mouse to any gamepad controller and back again.

Signcrafting and Skill Trees

2026-01-23T00:00:00+00:00

Most roguelites let you collect items to make overpowered builds, based on characters with some starting skills.
But I want to go further than that.
What if you could build your own whole skill tree? Let me show you Signcrafting!

What a Weekend

2025-12-15T00:00:00+00:00

Woah, what a weekend.
In case you missed it, last week I announced Signs of Danger, so please wishlist my game now</a> if you haven't already!
The reception has been way better than I expected.

Announcing Signs of Danger

2025-12-10T00:00:00+00:00

Huge news: today my game officially has a name, and a Steam page.
Wishlist Signs of Danger on Steam now!</a>
Seriously, every wishlist increases the odds of this game actually getting finished.

A Custom Level Editor

2025-12-05T00:00:00+00:00

If you want a tile-based level-editor, there are at least three good options to choose from.
But if you're making a custom falling sand engine and want to edit pixel-by-pixel? Nothing! So I made my own.
(also... pssst... something's coming next week!)

Touching Screens

2025-11-28T00:00:00+00:00

This game is for PC but odds are that something like 70% of you are reading this on your phone.
So wouldn't it be nice to be able to play the playable web build on your phone too?
Well, I just spent the last 2 days hacking in touchscreen support, so now (maybe) you can!

Blooming Hells

2025-11-14T00:00:00+00:00

"Blooming hells, has it really been 4 weeks since you heard from your friendly ~~ghost</del> falling sand dev?"~~
Well, err, yes, it has - sorry about that.
But I was actually talking about the other kind of blooming, that thing that makes lighting look cool.

Surviving MIGW

2025-10-17T00:00:00+00:00

I went to Melbourne International Games Week for the first time, and boy was it a lot.
I cobbled together "how to do MIGW" from a bunch of different sources, so I figured I'd write a guide for other newbies - especially other solo devs.
This is more instructional (read: more wordy & fewer gifs) than your usual fare, but we'll be back to our regularly scheduled programming (heh) next time.

Lighting a Falling Sand Game

2025-09-19T00:00:00+00:00

Someone on the internet said this game was ugly, which brought a tiny lil tear to my eye.
(I mean, they weren't wrong, but still - be nice to strangers, you know?)
So I spiced things up with some fancy lighting.

Texturing Terrain Tops

2025-08-29T00:00:00+00:00

All the terrain in this game is made of individually simulated "atoms" (pixels) - just like the water, acid, flammable gas, etc.
But terrain doesn't move, so how can we make it look a little more visually interesting?
Well, we can apply a texture - but it isn't quite as easy as that...

Accidental Aimbot

2025-08-08T00:00:00+00:00

Some players were having a hard time aiming their guns at enemies.
But that wasn't surprising, because I locked the aim input to only support 8 directions!
Why would I do something silly like that? And how could I help players hit their targets?

Simulating Cloth Capes

2025-07-11T00:00:00+00:00

For a while our player characters have been looking a bit, well, boring.
You know what they were really missing? Capes.
But how do you make a cape work in a pixel art game anyway?

Dropping In

2025-07-04T00:00:00+00:00

With abilities now being customized by collected perks, it wasn't fun to start over each time you died.
And that's doubly true with how easy it is to kill yourself - or be killed by fatal friendly fire!
But.. in this game where the entire level can be destroyed, how should respawning even work?

Loot Chests

2025-06-20T00:00:00+00:00

Okay, look, I know loot boxes get a bad name from the (many) publishers that use lootboxes to encourage microtransactions that milk their players for every last cent.
But I don't do microtransactions! So here we just have certified evil-free loot chests, filled with yummy yummy perks you can pick up in a game.
Also, we now have a way to edit abilities which doesn't blatantly break the game, which is always nice.

Ability Subroutines

2025-06-06T00:00:00+00:00

Last week's ability experiment was fun, but I had some concerns about it being too confusing.
So I doubled down on that! I've added "subroutines", which allow abilities to be modified on the fly.
I also added ammo for some abilities as a balancing mechanism, and a minimal ability heads up display.

Spellcasting 3.0: Perks

2025-05-30T00:00:00+00:00

I wasn't happy with the current spellcasting system, so I tried something totally different.
You stack perks and the combination of perks determines what spell gets cast.
It's just a prototype, but you can do some neat things with it already.

Three Shears

2025-05-23T00:00:00+00:00

This week's project hasn't quite come together yet, so let's talk about something totally different: rotating images.
Or to be more specific, let's talk about how rotating images can make weird holes appear in moving bodies made of atoms.
And an update on these updates: going forward, I'm giving myself the right to skip weekly updates.

Legit Levels

2025-05-16T00:00:00+00:00

A year ago I added support to the game for loading levels, but since then I didn't actually.. make any levels, ya know?
A whole year! That's embarrassing.
But.. what should levels look like? And let's take a quick look at some level tech improvements too.

Atomic Reaction Sounds

2025-05-09T00:00:00+00:00

We have sounds for reactions between atoms now, so you can hear when the level catches on fire, or when acid corrodes - even though there may be hundreds of atoms reacting!
And, let's talk about casting spells: how can a solo developer make sounds for each of the hundreds of possible spells in this game?
(Spoiler: dark FMOD rituals... after spending some hours reading the manual.)

Rolling Back Sound

2025-05-02T00:00:00+00:00

Ahh, rollback networking: you're wonderful, and I love you, but you make so many things even harder.
Let's talk about how adding sound makes networked multiplayer harder to pull off - something that you probably never thought would be the case.

Affecting Sound (with FMOD)

2025-04-25T00:00:00+00:00

No, that's not a typo - last week we were effecting sound, but this week we're affecting sound!
That is: I replaced the existing sound playing from last week with playing sound through a thing called "FMOD".
And FMOD has cool goodies to mess with sound on the fly.

Effecting Sound

2025-04-18T00:00:00+00:00

Toot toot! We're still on the polishing train, so this week I added support for some sound effects and music.
Turns out sound is a battle and a half, but at least we've finally got some boom barrels going BOOM now.

Timing Animations

2025-04-11T00:00:00+00:00

Last week I hinted that timing animations was a bit of a pain, but fear not!
This week we've got that all worked out, so enemies can play perfectly timed attack animations.

Back in Motion

2025-04-04T00:00:00+00:00

I'm back, and now only slightly sleep deprived! Yes, my Steam Deck is awesome (and Baby Mk II is doing great).
To celebrate, I decided to add some animations to player and enemy characters. They actually run and jump now!

Baby Break

2024-12-20T00:00:00+00:00

Happy holidays! When I went and sat on Santa's lap this last week, he pointedly told me:
Firstly, maybe I was getting too old for this lap-sitting business (haha, good one Santa).
Secondly, I should expect only one gift - and I would have to share it.

Networked Multiplayer on the Web

2024-12-13T00:00:00+00:00

Networked multiplayer now works in the playable web demo!
Crazy, right? I can barely believe it myself.

Bad Networks

2024-12-06T00:00:00+00:00

Last week I quipped that networked multiplayer should work on a dialup network connection.
But would it really? I dove into simulating bad network conditions to find out.

Networking Stats

2024-11-29T00:00:00+00:00

As of last week, network multiplayer worked in moment-to-moment gameplay, but still had sharp edges.
And to talk about those sharp edges, I need you to meet John.

Sorta Working Networking

2024-11-22T00:00:00+00:00

After a week of cleaning up last week's mess, networked multiplayer is starting to get into shape.
I've even added amazing features like "adding a new player" or "finishing a level without crashing the game".
And just for fun, you can edit levels with friends in a multiplayer game too!

A Networked Monster

2024-11-15T00:00:00+00:00

I implemented the most horribly hacked-up version of rollback-based networked multiplayer.
But it actually works! Or at least, it works during regular gameplay...

Spraying Fluids

2024-11-08T00:00:00+00:00

I rewrote most of the atom movement and made it about 40% faster on my big test level.
Yeah, I know, I've written a lot of updates about performance-tuning lately.
So instead, let's talk about how I made fluids behave a lot more, well, fluidly.

Circular Raycasting

2024-11-01T00:00:00+00:00

Improving performance of the atom simulation has been like pulling teeth: slow, painful, and not well suited to being featured in short videos paired with a couple hundred explanatory words.
So let's talk about something a tiny bit more fun: geometry! And a light serving of mathematics!
I know I've got you hooked now, so let's set the stage.

Nondeterminism And You

2024-10-25T00:00:00+00:00

I carefully made a surgical change that dramatically improved the performance of the entire game.
Or did I? Perhaps I instead opened up a can of worms, and one of those worms was a big ugly boy with "Nondeterminism" writ large upon his cursed frame, and then said worm proceeded to slowly bludgeon me to death?
Questions, always more questions... and to answer them, we need to start at the beginning, don't we?

Rollback Performance

2024-10-18T00:00:00+00:00

I simulated what game performance would be like in a rollback-networked online multiplayer world, and the answer was "Terrible".
So I made it a lot less terrible!
And I incorporated some feedback on last week's Lightning spell too.

Shocking Developments

2024-10-11T00:00:00+00:00

I added a lightning spell so now you have a full(-ish) roster of spells to cast.
I know, I know! It's a terrible pun title and you heard it coming a mile away. I couldn't resist.

Funding Found

2024-10-04T00:00:00+00:00

This week I've got some wild news to share: I've secured some funding!
I guess I'm a game developer for realsies now? Read on for the lowdown.

Creative Barriers

2024-09-27T00:00:00+00:00

Some weeks, it's hard to think of what to build next.
You catch up on email, start a new todo list, watch twenty-two vaguely relevant Youtube videos, fantasize about a total rewrite - and somehow you're still not inspired.
But, this week wasn't like that! I knew I needed a Barrier spell, and I just needed to build it.

Writing These Updates

2024-09-20T00:00:00+00:00

A surprisingly common question I get is "what are you using to send out those emails?".
So I figured I'd share a little of what goes on behind-the-scenes for these weekly updates.

Mine Your Own Business

2024-09-13T00:00:00+00:00

Continuing on our spell extravaganza, you can now cast Mine spells.
Mines are not just for exploding enemies! Turns out they're good for healing and jumping too. (Also for exploding your friends.)
And I added a basic player HUD so you know what your buttons will do.

Building a Spellbar

2024-09-06T00:00:00+00:00

If a player summons two elements that merge into another element, but the player didn't see the merging happen... did the merging even happen?
Not really! From the player's perspective the game is just unpredictable.
But, our new animated spellbar fixes that - and it was damn tricky to build!

Rocking Shields

2024-08-30T00:00:00+00:00

Continuing from last week's elemental spellcasting, this week I added support for casting Rock spells and Shield spells.
And, you can now aim spells with the mouse!

Elemental Spellcasting

2024-08-23T00:00:00+00:00

So far we have had spell casting based on a lookup table, and it worked but felt a little lackluster.
So this week I experimented with some twists and alternatives, including a Magicka-style spell casting based on mixing elements together.

Gesticulating Wildly

2024-08-16T00:00:00+00:00

I've been brainstorming how to make the spell system more customizable, and one of the ideas I had was to explore using gestures to cast spells.
So let's see how that went down!

Flinging Powder Atoms

2024-08-09T00:00:00+00:00

Being new to game dev while also working solo is great fun.
Most of the code was written by your least-favourite colleague: you from several months ago.
And the bigger your game gets, the more prolific that incompetent colleague seems to be.
But hey, you can always rewrite code, so that's what I did with the atom movement logic for powders (sand, coal, etc) this week.

Barrels of Boom

2024-08-02T00:00:00+00:00

Finally, we have explosive barrels! And explosive fireworks!
Wait, explosive... fireworks? Yep, and I'll tell you why.

Ladders and Shrooms

2024-07-26T00:00:00+00:00

Levels now have ladders. Seems simple, right? Think again!
And we're trying out some quick'n'dirty jump pads too.

Fixing Flow Killers

2024-07-19T00:00:00+00:00

Facing family flu season in full force, I figured fiddling with flow was fitting. 

Big Bada Boom

2024-07-12T00:00:00+00:00

A core feature of Broforce is chaotic chain reactions, and this week our untitled wizarding game gains a bit of boom juice too!
And, bonus: those of you using high refresh rate monitors get a much-needed bugfix.

Blooood

2024-07-05T00:00:00+00:00

In the spirit of making death more fun, enemies & players now get crushed by moving bodies, and bleed when they get hit!
For now it's mostly you doing the bleeding, since you don't have a spell that does physical damage to enemies yet. But that'll come!

Fiddling with Fire

2024-06-28T00:00:00+00:00

Fire wasn't anywhere near as much of an all-consuming inferno as it should be - so I fixed that.
Oh, players also have sprites now, so they're 87% less house-shaped.

Ragdolls

2024-06-21T00:00:00+00:00

Killed enemies now turn into physically-simulated corpses!
Finally a use for all that work to marry two physics engines together - phew.

Status Update

2024-06-14T00:00:00+00:00

This week I tried out a new spell-casting scheme, including adding 2 new spells.
And, atoms learned to apply status effects to characters, such as "on fire" and "poisoned".

Hot Pursuit

2024-06-07T00:00:00+00:00

This week, enemies progressed to toddler stage: they now chase players!
And we've got a new type of enemy too.

Pew Pew Pew

2024-05-31T00:00:00+00:00

This week, enemies learned to see the player and shoot in their general direction, which increased their deadliness by approximately infinity percent.

Target Practice

2024-05-24T00:00:00+00:00

This week, I added some enemies to kill, so watch out! The enemies might.. err.. well, they can't move or shoot yet so they're not super threatening.
Still, you can kill them with (two of your three) spells! So you could say they're target practice.

Architectural Questions

2024-05-17T00:00:00+00:00

The good thing about building an engine just for your game is that it lets your game do things other games can't (and it's often fun - or at least educational).
The bad thing about building an engine just for your game is that if you want to Frobber something, you first have to build Frobbering into your engine.
The ugly thing about building an engine just for your game is that building an engine means making a lot of choices (what can even be Frobbered?). And - especially when you're coming from a non-game-development background - it can be hard to tell whether you're making the right choices.

Level Progression

2024-05-10T00:00:00+00:00

This week, levels have a goal to reach, and reaching the goal loads the next level.
You can also die, and revive players by touching the spawn point again.

Tilemapping

2024-05-03T00:00:00+00:00

This week I added support for tile maps, so levels can be created with the LDTK editor</a>.

Loading Levels

2024-04-26T00:00:00+00:00

This week, I added support for loading levels on the web build.
So now you can try out some basic levels!

Let Sleeping Atoms Lie

2024-04-19T00:00:00+00:00

This week, liquids of different densities separate properly - so oil tends to float on water, rather than stay as globs floating in water.
The trick was in rewriting the atom sleep logic, which led to a bit of a performance optimization rollercoaster.
Also, you can cast three spells now, so let's have at it!

Multiplayer Fever Dreams

2024-04-12T00:00:00+00:00

Last week, I promised to write a bit more about how multiplayer could work (assuming I find funding for it).
Even the basics of multiplayer are complex, so this update turned out to be a lot of words - and it's a bit more technical than normal too. If that's not your jam, feel free to skip past the multiplayer theory-crafting.
(After the words re multiplayer, you can play with some sort-of-working oil - yes, we have oil now).

Boil and Toil

2024-04-05T00:00:00+00:00

This week, fire learned to boil water into steam, and water and acid now mix to make poison!
I also spent a lot of time on that most thrilling toil known to all small business owners: paperwork.
Wait, no, don't leave! Said paperwork might help networked multiplayer happen (maybe). That'd be cool, right?

Acid's Ire and Burning Fire

2024-03-29T00:00:00+00:00

This week, I implemented acid and fire! So now you can use acid to eat away the terrain and fire to, well, burn things.
And you can do those things to moving bodies too!
Plus: where there's fire, there's smoke - so now there's smoke too.

Discord and Making a Splash

2024-03-22T00:00:00+00:00

This week, a wild Slow Rush Discord server appears! And I reflect a bit on writing these updates.
What's that you say? Something about a game? Oh, right, that!
Well, you can now jump into water to splash it around, push falling sand & brick atoms out of the way, get buried by them, and (usually) dig yourself out - all the good stuff.

Atomic Holes and Multiplayer

2024-03-15T00:00:00+00:00

This week, it's my birthday!
To celebrate, I fixed the biggest outstanding bug in the "moving bodies to atoms" physics bridge: terrain can now have holes in it, without glitching out moving bodies!
Plus, the game now supports multiple players, including via gamepad controllers!

Designing a Magic System

2024-03-08T00:00:00+00:00

The prototype's ~~pixel</del> atom physics are coming along nicely, so this week I had a think about the other big part of the game: spell casting.~~
A neat physics system is fun for a bit, but it does get old pretty quick without some kind of goal like killing baddies, and in my unbiased opinion, killing baddies is way more fun when you have cool spells.

Playing Nice with Moving Bodies

2024-03-01T00:00:00+00:00

This week, atoms finally play nice with moving bodies thanks to last week's particles</a>.
That means you can fling a moving body into water and the water makes a little wave, and moving bodies & players don't have their movement blocked by falling sand anymore! (Oh, also, atom movement is vaguely plausible again, unlike last week - yay!)
There was a lot of fiddling to get this all somewhat working, so let's get our feet wet.

Particles, for real this time

2024-02-23T00:00:00+00:00

This week I had a second shot at implementing particles, which are my planned solution for stopping atoms from crushing moving bodies (so that dropping sand on a box doesn't cause the box to flip out).
And this time it worked! Or at least, the particle implementation worked. And I added a neat time travel debugging feature to help figure out why the rest of things weren't working.

Making Atoms Kinetic

2024-02-16T00:00:00+00:00

This week I can confidently say that falling sand no longer completely crushes a moveable body that it falls onto! (It does still crush it a lot, which isn't the best, but we'll get to that.)
First, a small announcement: I've formally resigned from my day job! I had already been working on this fulltime via extended leave, but from March 2nd onwards it'll be official. That did mean that I spent entirely way too much time this week wrapping day job things up, but now that it's mostly done I can get back to focusing on making physics pixels move around semi-predictably.
Secondly, some terminology: I'm sick of writing "physics pixels", so let's call them "atoms". They're the smallest indivisible unit of our game, and we know for a fact that atoms cannot be divided further, so the shoe fits.
Now, back to our usual programming: let's talk about inertia, and our blatant disregard of it.

Optimizing the Physics Bridge

2024-02-09T00:00:00+00:00

We're back with another Wizard-Pixels-flavored update, again on duct-taping together two physics worlds!
Last time</a> we ended up with moving (rigid body) colliders being created from physics-pixels, and physics-pixels were stopped by fixed rigid body colliders - so you could stack boxes on top of a sand pile, and sand would be stopped by fixed platforms.
This week, well, you can still mainly do those things. But! Wait! Don't leave! This week it performs at least 10x better, which makes it actually playable! And you can draw custom moving bodies, and actually walk on the sand as a player too - both of which are sort of neat.
How is this black magic possible? Let me tell you!

Bridging Physics Worlds

2024-02-02T00:00:00+00:00

Welcome back! The game will have physics taking part in the magic system, and currently it has two types of physics in it: "pixel physics" (falling sand, flowing water, etc) and "rigid body physics" (boxes, balls, etc).
More physics is better, right? Sure, except for that right now they can't interact with each other at all. Which means a ball will fall straight through a sand pile. Or water falls straight through platforms rather than flowing around it. Not very good, so let's fix it!

Pixel Perfect Rendering

2024-01-26T00:00:00+00:00

In last week's playable demo, the edge of the world would jitter back and forth about the width of a pixel when you moved your character - which looked terrible and was very distracting.
This was caused by the rendering (the camera) not being "pixel perfect", and - I'm not going to lie - fixing it was a hell of a rabbit hole! You might think it's a trivial problem to solve, but each game has slightly different constraints, so let's take a quick tour through the many different aspects of it!

Making Platforming Feel Good

2024-01-19T00:00:00+00:00

This week, I added physics-based platforming support - so now you can control a little box who can move around, jump and push some balls around.
Making movement feel good is really tricky! For example, real life physics would lead you to think that a jump makes you travel in a parabola, so that the time taken to reach the peak of your jump is the same as the time to fall from the peak to the ground... but in a game, that feels terrible!

Choosing an Engine

2024-01-12T00:00:00+00:00

This week, I ported my "game" to two different Rust game engines. Why two engines? Why Rust? Let's dive in!
As a reminder, I'm aiming for a 2D game with "pixel physics for PC"</a>, which means it has some high level requirements from any engine...

The Game So Far

2024-01-05T00:00:00+00:00

New year, new adventure!
I'm making this thing a little more official by spinning up a website so people can follow along, so let's talk a bit about what game we're aiming to build.