Getting Started With Guy Something Something Darkside Online
I've been running this thing for about two years now, and the documentation around it is still pretty scattered. I'll walk through how to actually use it without the usual promotional fluff. It's a browser-based utility for generating dark-themed visual overlays and texture packs for indie game projects. You load a base image, pick from a set of procedural filters, and export to PNG or PSD. That's the surface version. The actual utility comes from the scriptable layer, which lets you chain multiple filter passes and automate batch processing. The interface looks minimal when you first load it, and that's intentional. Most of the controls are hidden behind panels you have to click to expand. I wasted about an hour on my first session trying to find the export button because it lives inside a collapsed settings drawer that doesn't open unless you hover over the correct area. Once I figured that out, the whole thing made more sense.
Installation and Setup
You don't install it in the traditional sense. There's a download link on the main page that gives you a self-contained web app bundle. You drop the folder onto your local server or just open the index.html file directly in Chrome or Firefox. It runs entirely client-side, so nothing gets uploaded anywhere. The initial load takes roughly 4 seconds on a decent connection. If you're pulling it from the project repo, expect the first run to grab about 80MB of assets and libraries. After that everything caches locally. I've seen people complain about the first-run wait time, but it's a one-time thing. One thing the docs don't mention clearly: you need WebGL 2.0 enabled. If your browser is running in compatibility mode, half the filters won't render and you'll just see a blank canvas. Check your browser flags if things look weird on startup.
Core Workflow
Here's how I actually use it day to day. Load your source image first, then set the canvas dimensions to match. The filters are applied in the order they appear in the stack, and the order matters a lot. I learned that the hard way when I swapped two filter positions and spent twenty minutes trying to figure out why the output looked completely wrong instead of just darker. The main filters break down into these categories: Color Shift — Adjusts hue, saturation, and luminance curves independently. Useful for killing color entirely or pushing everything toward a monochrome base before adding noise.
Get the Full Details
Texture Overlay — Brings in scanned paper grain, film scratches, or custom PNG displacement maps. You control opacity and blend mode per layer. The built-in textures are decent but limited. I ended up scanning my own paper textures at 600 DPI and converting them to grayscale PNGs for better results. Vignette and Light Leak — These two often get confused. Vignette darkens the edges cleanly. Light leak simulates a specific type of lens flare artifact that looks more organic. If you want something to feel atmospheric rather than graded, use light leak. If you want control, use vignette. Noise and Film Grain — Adds random pixel variation. The key setting here is luminance versus chroma noise. Chroma noise gives you that colorful film look. Luminance noise is just gray static. Most people want chroma but don't realize they're getting luminance by default.
The export options give you PNG, PSD with layers intact, and a limited TIFF option. The PSD export preserves every filter as a separate layer, which is valuable if you need to go back and tweak things in Photoshop later.
Scripting and Automation
This is where it actually saves time. The scripting layer uses a JavaScript API that lets you define filter sequences as reusable templates. I wrote a script that applies a consistent dark overlay pass across 40+ texture images in one batch. Without the script, that would have been about 2 hours of manual work. With it, closer to 15 minutes depending on your machine. Sample structure looks like this: load image input folder
apply color shift filter at -15 luminance, +8 hue shift apply texture overlay with paper_grain_02 at 0.4 opacity multiply blend apply vignette radius 0.6 strength 0.3
apply noise chroma 0.15 luminance 0.05 export to output folder as PNG You save these as .js files in the scripts directory and call them from the main interface or run them headless through the CLI if you have Node set up. The CLI option is undocumented but works if you open the developer console and type the right command. I found it by reading the source, not the docs.
Edge Case I Ran Into
There's a known issue when your source image has an alpha channel. The app strips the alpha during the first filter pass, which means any transparency you had gets baked into the background color instead of staying transparent. This breaks workflows where you need the output to remain transparent for compositing later. My workaround: duplicate your image layer in Photoshop first, flatten it to white, run it through Guy Something Something Darkside Online, then bring the result back and re-apply the alpha mask from your original file. It adds about 30 seconds per image but preserves transparency correctly. I've reported this to the dev team twice. No fix yet.
What It Doesn't Do Well
The filter library is small compared to dedicated tools like Photoshop or Krita. If you need complex gradient mapping or advanced blending modes beyond multiply and screen, you'll hit a wall. The color grading tools are also shallow — you get curves but no RGB split or halation simulation. Performance drops noticeably with large images. Processing a 4K source with three or more filter layers can take 10 to 15 seconds per pass in the browser. I stopped using it for anything above 2K resolution and just do the heavy lifting in Photoshop instead. There's also no cloud saving of projects. Everything lives locally in your browser cache. Clear your cache and your saved sessions are gone. I keep a backup folder of my working files outside the app just in case.
Where to Get It
The official build is available from the project's GitHub releases page. Download the latest stable version — the beta builds have been crashing on Safari recently. There's no installer, just the folder. Put it somewhere permanent on your drive so you're not moving it around. If you want a quicker start, there's a web-hosted version at the project's main domain. It has the same functionality but runs everything through the cloud, which defeats the privacy aspect. I prefer the local install personally.
Final Thoughts on Guy Something Something Darkside Online
It fills a narrow niche well — quick dark overlay generation for game assets and texture work. It's not a replacement for full editing software, and it has enough rough edges that you'll run into quirks within the first week. The scripting layer is the real value if you're doing repeated work. I use it maybe three times a week, usually for quick texture passes before I move files into a DCC tool for final polish. The community is small but active enough on Discord. The dev posts update notes occasionally, though response times on issues vary. If you're willing to work around the limitations, it does what it says without being heavy or expensive.
