I am creating an indicator that is DOM like which displays on the right side of a chart

I am using graphics.DrawRectangle and graphics.DrawString to accomplish the display

But as time goes on the number of items to draw will increase

I am concerned it will start to consume far too much CPU

Is there a way to use these draw methods to instantly draw on the screen, not just on a refresh? This way only the newest graphics is rendered, instead of the needing to run through the my entire display graphics entity list again.

For example at price Y draw a box with the price in it at x = xlocation

when price changes to Y + 1 tick, draw another box above the previous box (at new price level )but still at x = xlocation

As my code is today, I need to draw 2 boxes when price changes.

I want to draw just 1 to reduce CPU impact

I would only draw 2 if a full refresh occurs (such as when F5 is pressed)

The impact is minimal for the low level direct draw routines, you can draw hundreds with little impact, and also remember that the Plot routine is typically called at user speed (e.g. 0.4/0.5s) so it's not a big deal.