Partial rerendering

**Is your feature request related to a problem? Please describe.**
I want to build an interface where I have potentially a long render loop for an raw texture image, but most of the rest of the interface is static: buttons, tabs, etc. which never change.

**Describe the solution you'd like**
I would like to only partially rerender the GUI, only in places where it matters, and not rerender the whole complex static interface at every render loop. Seems to me like a waste of resources.

**Describe alternatives you've considered**
I guess what I'm describing is similar to a sort of reactive programming, which is used a lot in web html programming like VueJS, ReactJS etc. but I couldn't find a similar pattern in DPG.

**Additional context**
Here's a program I'm working on for which I'm trying to speed up the processing.