Pixel-based (Screen-space) Layer in deck.gl – Custom Layer vs Existing Solutions?

[abdcelik]

I’m working with deck.gl and I need a pixel-based layer that behaves similarly to an IconLayer.

• The layer should be screen-space / pixel-based
• It should be rendered on the canvas
• It should be independent from camera target and viewState
• Zooming or panning the map should not affect its size

The layer I want to create is conceptually a gizmo, similar to the gizmos used in three.js.

Currently, I have a CompositeLayer that partially handles this use case. However, at certain zoom levels, usability drops significantly.
Trying to compensate by dynamically scaling the layer based on zoom level doesn’t seem like a good or robust solution either.

Questions

• Is implementing a custom layer the correct approach for this?
• Is there a simpler or more idiomatic solution in deck.gl that I might be missing?
• Are deck.gl layers fundamentally designed to be world-space only, rather than screen-space?
• Why doesn’t deck.gl provide built-in pixel-based / screen-space layers?
• Am I trying to solve this in the wrong place (i.e., should this not be a layer at all)?

Any guidance or architectural recommendations would be appreciated.

[abdcelik]

I resolved the zoom-dependent gizmo sizing issue by creating a composite layer with the following approach: I override shouldUpdateState to include viewportChanged as an update trigger. On every update, pixel-to-world scale is calculated, translating fixed pixel dimensions into dynamic world coordinates that scale inversely with viewport zoom.

I'm aware this CPU-based scaling isn't the most performant solution—a GPU-based shader approach would be better—but as I'm new to the visualization domain and shader programming, this was the best solution I could implement.