Suggestion: Turn off Viewport Options->Realtime should use minimum CPU

UE4 Editor always takes 30% of my CPU usage even I don’t move my camera. I consider it is a design bug of Unreal Engine: always render every frame even there is no change in the viewport. In Unity3D engine, if I don’t move my camera around, the CPU usage is very low. My suggestion is that if I turn off Viewport Options->Realtime, UE4 Editor checks if there is a navigation happens or whatever reason to cause the content in the viewport changes. If there is a change in the viewport, render the viewport. Otherwise, skip render process. I hope engineers in Epic can talk about this and have it included in future version of the UE4. Thanks!

The viewport is going to depend more on the GPU than the CPU, the overall editor will be using the CPU no matter what.

I didn’t have time to read the source code, but I guess currently UE4 editor renders every frame like what most games do. Like this:

while (true) {
Update(); // Game logic, etc.
Render(); // Render frame in the viewport

What I’d like it to do is that only render the frame when viewport has changed (for example, the user tumbles the viewport around, etc.). Like this:

while (true) {
if (viewportHasChanged) {

Even if you dont move your camera, the viewport still might need updates. Think about animated materials, etc.

This can be a very slippery approach.

For once, the editor does not run “game logic”. So the render loop in the editor is not like most games.
The ditor isnt a game

How do you know that the CPU usage is attributed to the viewport calculations… Could also be the ditor streaming in other resources because you changed edit mode…
Does the CPU load go down when you maximize one of the other viewports?

Vote for the following 2 items if you feel that editor performance is problematic for you - they are the closest items listed on trello for this:

If realtime is off, animated materials should stop animating.

Voted. Thanks for the links!