Massive performance impact with brush-based tools in new terrain editor

When using a brush-based tool in the terrain editor, IE: any tool which creates an object in the viewport which follows the cursor. A massive constant lag-spike starts to occur, making the tools absolutely un-usable. This lag spike was not present in the old terrain editor.

Affected Tools:

System Info:
CPU: Intel(R) Core™ i5-8400 CPU @ 2.80GHz
GPU: NVIDIA GeForce GTX 1050
Memory: 16GB


I have attached a much more detailed microprofiler dump in the private-message.

Enabled beta-features:

Expected behavior

I expect no major performance decreases to occur when using brush-based tools just like the old terrain editor.

A private message is associated with this bug report


Wooo! Thank you for this, been waiting on someone to post this exact bug report for months.

I have the same issue, makes terrain completely unworkable. Also had zero issues with the previous terrain editor.

Just selecting a tool is enough to start it, don’t even have to interact with or otherwise modify the terrain. Goes away as soon the tool is deselected.

For me the select, fill, and transform tools are also affected, but only when you move them, as opposed to the others that are constant.