Ebiten VS bevy

Reading ebiten docs and source code they very clearly state that writing RGBA bytes to an image is slow, and shouldn't really be done every frame, at least many times per frame. This is where I thought my performance was being lost, and it sent me looking for answers for ages. Turns out, I was wrong and right.

I love Go, yet I've never thought of it as a language with usable game engines. I'm extremely happy to find I was very wrong about that!

I'm woefully behind the curve on compiling to WASM, though, and I've yet to experiment much with tinygo so I have no idea how far I would get in creating a game people could enjoy in a browser without having to download a big bundle of assets. It's reassuring to see WASM mentioned explicitly as a compilation target [1] by Ebitengine though.

[1] https://github.com/hajimehoshi/ebiten

For other OSes, see https://github.com/hajimehoshi/ebiten/issues/1162

What about learning Go with Ebiten? Or Rust with Bevy?

Actually, there is a game engine in Go. Ebiten(gine) is actually really popular and has already been used for a few games in production

Check out this thread, some of the linked repositories might be of help. https://github.com/hajimehoshi/ebiten/discussions/1527

// consider having a laser type to deal with orientation, etc // basic information to draw sprites, track position and update position type Body struct { // positions x float64 y float64 // velocities vx float64 vy float64 // get height and width from sheet.xml using sp width int height int } type Enemy struct { Body sp int health int } type Laser struct { Body sp int } type Mode int const ( ModeTitle Mode = iota ModeGame ModeGameOver ) var ( arcadeFont font.Face smallArcadeFont font.Face ) // fonts and sizes func init() { tt, err := truetype.Parse(fonts.ArcadeN_ttf) if err != nil { log.Fatal(err) } const dpi = 72 arcadeFont = truetype.NewFace(tt, &truetype.Options{ Size: fontSize, DPI: dpi, Hinting: font.HintingFull, }) smallArcadeFont = truetype.NewFace(tt, &truetype.Options{ Size: smallFontSize, DPI: dpi, Hinting: font.HintingFull, }) } // in the future have a laser type struct, spriteImgNum, and number of animations type Game struct { mode Mode level int // tracks location of player and maybe health Player struct { Body health int laserType int canShoot bool sp int // consider adding in height and width of player object // all of the sprites seem to be the same // TODO set global width } PLasers []*Laser Enemies []*Enemy ELasers []*Laser gameoverCount int } // load images func init() { // sprites img, _, err := image.Decode(bytes.NewReader(resources.Sprites_png)) if err != nil { log.Fatal(err) } gameImages, _ = ebiten.NewImageFromImage(img, ebiten.FilterDefault) // backgrounds img, _, err = image.Decode(bytes.NewReader(resources.Starfieldreal_jpg)) if err != nil { log.Fatal(err) } bgImage, _ = ebiten.NewImageFromImage(img, ebiten.FilterDefault) } // background image logic from // # https://github.com/hajimehoshi/ebiten/blob/master/examples/infinitescroll/main.go var ( theViewport = &viewport{} ) type viewport struct { x16 int y16 int } func (p *viewport) Move() { w, h := bgImage.Size() maxX16 := w * 16 maxY16 := h * 16 p.x16 += w / 32 p.y16 += h / 32 p.x16 %= maxX16 p.y16 %= maxY16 }

I noticed a similar issue when I got my MBP with the framebuffer not matching the window size and this has to do with the DPI settings. This GitHub link helped me understand the issue better and I hope it can be of assistance to you https://github.com/hajimehoshi/ebiten/pull/1811

This program also demonstrates how great Ebitengine is and how you can port GLSL shaders to it almost 1 to 1.

Basic gist: built in Go with ebitengine, medieval fantasy, pixel art

Bevy. A very young engine where you need to write the game entirely in Rust—that was appealing. But fatal flaws overshadowed everything: no editor, the engine brutally enforces the ECS approach, and the game's architecture must literally bend to fit this paradigm. So, you won't migrate to another engine at all—you just throw away all the code and start from scratch.

Missing one of the best choices as long as "maturity" isn't on the top of your list: Bevy - https://bevyengine.org/

Game engine written in Rust, leveraging ECS in almost every place and way, with a really capable WASM export option. Wrestling ECS for the first time might take you some time, but in my experience helps you keep game code as clean and decoupled as game code could be.

I don't see WASM/WebGPU changing anything when it comes to gaming, as an industry, personally. 3d visualizations and interactive websites? Yeah definitely a nice improvement over WebGL 2, if years late.

WebGPU is pretty far behind what AAA games are using even as of 6 years ago. There's extra overhead and security in the WebGPU spec that AAA games do not want. Browsers do not lend themselves to downloading 300gb of assets.

Additionally, indie devs aren't using Steam for the technical capabilities. It's purely about marketshare. Video games are a highly saturated market. The users are all on Steam, getting their recommendations from Steam, and buying games in Steam sales. Hence all the indie developers publish to Steam. I don't see a web browser being appealing as a platform, because there's no way for developers to advertise to users.

That's also only indie games. AAA games use their own launchers, because they don't _need_ the discoverability from being on Steam. So they don't, and avoid the fees. If anything users _want_ the Steam monopoly, because they like the platform, and hate the walled garden launchers from AAA companies.

(I work on high end rendering features for the Bevy game engine https://bevyengine.org, and have extensive experience with WebGPU)

I was working through an example in the repo for the Bevy game engine recently and came across this code

That's possible. I did spend quite a bit of time tinkering with compiler flags, and followed the recommendations.

Some notes I found just now seems to agree with my results, though: https://github.com/bevyengine/bevy/issues/3978#issuecomment-...

I cannot recommend immediate mode GUI programming based on the limitations I've experienced working with egui.

egui does not support putting two widgets in the center of the screen: https://github.com/emilk/egui/issues/3211

It's really easy to get started with immediate mode, it's really easy to bust out some UI, but the second you start trying to involve dynamically resized context and responsive layouts -- abandon all hope. The fact it has to calculate everything in a single pass makes these things hard/impossible.

... that said, I'm still using it for https://ant.care/ (https://github.com/MeoMix/symbiants) because it's the best thing I've found. I'm crossing my fingers that Bevy's UI story (or Kayak https://github.com/StarArawn/kayak_ui) become significantly more fleshed out sooner rather than later. Bevy 0.13 should have lots more in this area though (https://github.com/bevyengine/bevy/discussions/9538)

I've also been enjoying building My First Game™ in Bevy using ECS. The community around Bevy really shines, but Flecs (https://github.com/SanderMertens/flecs) is arguably a more mature, open-source ECS implementation. You don't get to write in Rust, though, which makes it less cool in my book :)

I'm not very proud of the code I've written because I've found writing a game to be much more confusing than building websites + backends, but, as the author notes, it certainly feels more elegant than OOP or globals given the context.

I'm building for WASM and Bevy's parallelism isn't supported in that context (yet? https://github.com/bevyengine/bevy/issues/4078), so the performance wins are just so-so. Sharing a thread with UI rendering suuucks.

If anyone wants to browse some code or ask questions, feel free! https://github.com/MeoMix/symbiants

These days, some game engines have done pretty well at making compute shaders easy to use (such as Bevy [1] -- disclaimer, I contribute to that engine). But telling the scientific/financial/etc. community that they need to run their code inside a game engine to get a decent experience is a hard sell. It's not a great situation compared to how easy it is on NVIDIA's stack.

[1]: https://github.com/bevyengine/bevy/blob/main/examples/shader...

This is the API you need: https://github.com/bevyengine/bevy/pull/9774