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Daily Driver: Happy New Year!

by Matt Sephton — Sat, 09 Jan 2021 00:00:00 +0000

I hope you’re safe and well and wish you a great 2021. I’m back at it, and am confident this year will be the year of Daily Driver and more besides!

Recent work on the game includes improvements to the physics of in-game objects and creation of yet more vehicles and levels.

“The car’s the star”, as they say, so I have sunk untold hours into both the physics and graphics of many different cars to ensure that the depth of control and animation is enough to hold a players interest for the time I hope they will spend with my game. There’s no final vehicle line-up, as often some cars don’t look unique enough after the first rough model is tested in the game. But these two are keepers!

Interestingly, both these vehicles show off one aspect of the game that I’ve not really talked about so far: reference and nods to classic games. Here we can see an RC car (whose antenna wobbles!) that is a nod to games like Re-volt, RC Revenge, Smash Cars, RC de Go!, Excite Truck, RC Pro-Am etc. And the forklift is a nod to Shenmue and the infamous New Yokosuka Harbor District.

Daily Driver: Weight Transfer

by Matt Sephton — Sat, 03 Oct 2020 00:00:00 +0000

I’ve been playing old Japanese PlayStation game Touge Max G and besides this having a gymkhana mode similar to aspects of Daily Driver, it also has a realistic handling model. One of the things that struck me about that was how the car rocks back and forth when accelerating and braking/reversing. One of the other games in the Touge series also has a school mode that talks you through this concept of weight transfer. It’s realistic and adds some level of dynamics to the car, making it feel less like a solid block sliding around.

So I’ve added this effect to Daily Driver and will be refining it going forward. I find it breathes extra life into the car just as it does in other games with full 3D physics modelling. It requires 3x the number of car sprites but because I render them from 3D it’s not much extra work and I think it’s well worth the effort.

Daily Driver: from 3D to 2D

by Matt Sephton — Wed, 27 May 2020 00:00:00 +0000

At this point, the only thing that remained of the prototype was the car sprite so I wondered about creating a new one myself. It uses 32 different images of the car with different rotations, making for smooth animation and movement on screen.

Whilst I could draw all those frames by hand, I decided to go down a path that could produce assets on demand. That way if I change my mind I can reprocess the assets whenever I feel like it. The initial process was easy to setup, but I’ve been taking and simplifying the automation process ever since.

I’d previously used OpenSCAD to create 3D models, so it was a natural and easy choice. Also, it’s the only 3D app I’ve ever used—not even Blender! Models are created using a definition language (think of it as a bit like CSS) where you can define shapes and how they interact. I also use the animation function to set the viewpoint and rotate the car whilst automatically saving the images.

In OpenSCAD I lock the view angle and zoom. I tie rotation to the animation value $t. Then I run the animation and click a box to have the app spit out all the rotated images for me.

The output images need a little post-processing, so I use a single Retrobatch workflow to: crop, add transparency, invert, a few other things, and finally stitch the 32 images into one long sprite sheet. (On Windows you can use Photobat)

Finally, I run the sprite sheet through a bespoke dithering tool that allows for “live” manual tweaking to convert the greyscale images to 1-bit.

That’s good enough for my current requirements. Later on I would want extra detail in the renders, either through texturing or by hand.

29 May 2020. Soon after I would start rendering the wheels turning and after that the body so it rocks from side to side.

Daily Driver: Physics

by Matt Sephton — Sun, 24 May 2020 00:00:00 +0000

Now that I was convinced that a driving game could be fun, I was unhappy with the controls and very rudimentary “physics” that the car had. It just didn’t feel very real or compelling; there wasn’t enough depth to the control scheme.

So I used Marco Monster’s Car Physics article (and looked at source code for various implementations of his technique) to implement more realistic car physics including drifting and skid marks. This was a bit of a watershed moment: this was the game I wanted to spend all my time on.