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Camiel Wijffels · Guest

Hi there,
I wonder, when I resize a form to a larger size, the form is repainted
without any events being triggered. When picking the bottom-right corner of
the window, and enlarging the window, all controls stay exactly where they
should be, aligned to the top-left corner (when not using anchors or
alignment). But when picking up the top-left corner of the window, and
enlarging the window, all controls suddenly move according to the resizing
(again when not using anchors or alignment). And they do this without
flicker. However, when I have, for example, a statusbar on the bottom-edge
of my window, this one flickers - just for a few millseconds. This is caused
by moving the entire window, according to the top-left resize operation, and
only AFTER this redraw has taken place, the system realizes that the
statusbar should be at the bottom, so repainting it!
WHY?
Is the on-screen movement so fast that no one can see? Cause when I copy a
bitmap on my machine to the screen, I see a few flickers - this takes
approximatly 25 ms on my machine (666 MHz, 1000x1000x16)
If the on-screen movement is so fast, why dont I use the same technique?
What API calls do I have to dive into to know what is going on?
--
Met vriendelijke groet, Camiel Wijffels
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Tomaz Koritnik · Guest

Hi

Some controls are not written properly and they don't handle paint
messages the right way. Usually this is caused by processing WM_ERASEBKGND
message but some controls may erase background on WM_PAINT message. If this
control is not double-buffered then background is first painted and then the
contents of the control which causes flickering. I don't know what do you
mean in the example with status bar. Can you describe it more clearly.

regards,
Tomaz,

"Camiel Wijffels" <C.Wijffels (AT) BluePrintST (DOT) com> wrote

Camiel Wijffels · Guest

Take a slow machine, ie 100 MHz. Start wordpad and resize the top-size of
the wordpad main form. You see what I mean?
--
Met vriendelijke groet, Camiel Wijffels
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Vertrouwelijk. Dit bericht is uitsluitend bestemd voor de geadresseerde.
Confidential. This message is ment for the addressed recipient only.
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.. I don't know what do you