[Lazarus] Smooth scrolling label (marquee)

Mark Morgan Lloyd markMLl.lazarus at telemetry.co.uk
Wed Nov 11 10:08:09 CET 2015

Michael Schnell wrote:
> On 11/10/2015 12:30 PM, Luca Olivetti wrote:
>> - it is very cpu intensive (I have to put it over a picture, so the 
>> invalidate will also force the repainting of the bitmap I guess)
> The only cure for this is using the graphic processor: only once create 
> a wide pixel array from the text and then use Direct X (Open GL or 
> similar API) to display part of the text "behind" in a rectangle.

Using OpenGL etc. risks breaking the program for anybody accessing it 
over remote X (including SSH) or VNC etc. (either for routine use or 
remote support).

I believe there are ways that OpenGL can be mapped over a LAN, but in 
practice it would- at present at least- be safest to assume that these 
aren't reliable and at the very least provide a user option to make sure 
the program doesn't attempt to use it for anything that is basically 

Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

[Opinions above are the author's, not those of his employers or colleagues]

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