v1.9.1
- Fixes icons scrambling positions if the filter was ever used.
- Fixes rare NRE on tree gen.

v1.9
- Major update: a mod filter button has been added below the search field. This will regenerate the tree with only that mod's research projects + any prereqs that's relevant to it.
- Lots of misc code optimizations all throughout and a slightly leaner .dll

v1.8.2
- Small change to make the code more defensive against external research content issues.

v1.8.1
- Fixes horizontal scrolling not working (alt+scroll). Also fixes the top bar scrolling, decoupling it from the main view area. Thanks Bardez for the insight.

v1.8
- New mod option: Read only mode. This feature is used to support mods like semi-random research. It is automatically enabled if it detects such mods are active.

v1.7.2
- Edge case NRE fix related to searching.

v1.7.1
- Another round of code optimization related to rendering (frame rate while browsing the tree). Should be around 20% faster now, more for large modlists.
- The button to regenerate the tree in the mod options has been removed and this is just handled automatically now.

v1.7
- Perhaps the last phase of code optimization. The tree now generates near instantly for all configurations (about 7ms for me with mods loaded).
- New feature: Sort by tabs. You can either pick this, or the old sorting option of sorting by mods.
- Deprecated: Mod options related to generating the tree on game load have been removed. The tree now only generates once you view it for the first time. This old feature was more of a bandaid solution for the slow generation time, and is no longer needed.

Major optimizations made to initial tree generation, upwards to 4x faster generation now for some configurations.

I've had a couple stray reports of the tree gen crashing. This investigation lead to the optimizations and should hopefully sort those problems out as well.

Whoops, I accidentally left a debugging file in the previous update that I was using to track down the node issue. This update removes it.

If you see unusual tech projects in your tech tree, then you need to update your mod (steam sometimes fails to automatically update mods if there's more than 1 update in a day).