Deprecated heightmap terrain support?

I currently use heightmap format terrain tiles and looked at the spec recently and was surprised to see that the format is now deprecated:

https://github.com/AnalyticalGraphicsInc/cesium/wiki/heightmap-1.0-terrain-format

“This file exists for historical reasons. This format is deprecated and should not be used. Consider quantized-mesh instead.”

I searched and did not see any announcement or other info about this, and I would like to learn more:

  1. Most importantly, is there a timeline for when support will be removed from Cesium?

  2. Are there any current or planned features that are incompatible with heightmap terrain?

  3. Was there an announcement for this? I’d like to keep abreast of changes like this, so I’d like to know where I should pay attention.

  4. Why is heightmap being deprecated? I understand quantized-mesh is considered better for rendering, but heightmap is simple and much easier to generate tiles for.

Thanks,

Jacob

Hey Jacob,

We do usually make announcements like this on the forum and blog/Twitter, but this one must have slipped through. I think the reason it wasn’t a bigger announcement is just because it’s the format that’s no longer officially maintained, which is different from support for it in CesiumJS being deprecated. As far as I’m aware, heightmap support in CesiumJS is not deprecated and there are no current plans to remove support for it. There were some recent major improvements done to terrain (https://github.com/AnalyticalGraphicsInc/cesium/pull/7061) and those apply regardless of how the terrain is loaded in for example.

In any case, the nice thing about open source is that features won’t ever really go away as long as there are people still using it and willing to maintain it. We do believe quantized-mesh is a much better format for rendering, which is a big goal of CesiumJS: getting large amounts of data streamed in and on screen as fast possible. ion as a platform also exists to make generating/converting these formats a lot easier for everyone:

Anyone have an objection if I remove that deprecation note? I don’t know where it came from, and as far as I’m concerned it’s not true. Sure, quantized-mesh is better, but heightmap-1.0 is still useful for the reasons Jacob mentioned above.

I’ll change it to mention that quantized-mesh and Ion are super cool and a better choice in many cases.

Kevin

I spoke to some others on the team. I think we can safely remove the deprecation note and just say something like, the format is complete or just like leaving the “Consider quantized mesh” part.

Yeah, that sounds much better. If there’s no plans to actually remove support for heightmap format, then I wouldn’t consider it deprecated.

Plus, while heightmaps don’t result in terrain that’s as “realistic” as quantized-mesh, it’s a much simpler format to generate yourself.