Re: fast drawing in delphi

Maldona8 schrieb:

I will try briefly to explain it:

The problem:
-------------
We have a multichannel signal we have to screen in order to see the development of a process
The process is very fast (in terms of microseconds to milliseconds). It happens for several seconds and
then many other processes start to happen and then it becomes meaningless to continue monitoring, but the first seconds are very significatives in terms of valuable information.
We have sophisticated sensors that are able to monitor the process, but the measured data comes from a huge amount of channels and we have to organize that information somehow, if we want to understand what's going on.

Then it might be better to store the information (hexagon colors) about the first few seconds, for later replay in fast or slow motion, perhaps for multiple times. The stored information could be presented by a separate "monitor" program, independently from the real-time processing in the other programs. Multithreading or multitasking is frequently used in real time applications.

Otherwise, if the display really should present a real-time "movie", I'd paint the changes directly on the screen. It shouldn't be a problem, if some changes of the same hexagons are not painted?
(Then it also might make sense to use DirectX, to write directly to the video memory).

DoDi

P.S.: Another test, now with stored hexagon bitmaps for every color:
I could paint 9 samples per second, each of 100*100 polygons.
Hint: Image1.Refresh must be used after each sample, to make it visible.

Painting to the canvas of the form, with or without double buffering, allows for over 20 samples per second, with some flicker. The flickering certainly could be suppressed, if double buffering and appropriate enable/disable repaints were used. I just couldn't find the property, should be something like LockUpdates (not in D4)?
Other graphics cards may not flicker at all?

.

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