[Lazarus] Smooth scrolling label (marquee)

Luca Olivetti luca at wetron.es
Wed Nov 11 09:28:42 CET 2015

El 11/11/15 a les 01:21, Luca Olivetti ha escrit:
> El 10/11/15 a les 23:37, Graeme Geldenhuys ha escrit:
>> On 2015-11-10 21:09, Luca Olivetti wrote:
>>> But in the end I have to render it on the LCL canvas
>> Via a single BitBlt which should be more than fast enough for what you
>> described. Unless LCL is seriously broken.
> I don't know if it's broken, but, AFAIK, there are two ways to animate
> something
> 1) with a timer (constrained by the windows resolution)
> 2) with a thread+synchronize (only the main thread can access the gui,
> and the constraint here is the rate the application loop calls
> CheckSynchronize)
> But what really puzzles me is the different behavior between xp and 7
> (maybe it's aero, I could try disabling it). The fact that it's a font
> of size 100 with a bitmap below it doesn't help, but it should be possible.

Well, I just found out that in a virtual machine (be it xp or 7) the 
timer resolution is 10ms, while in real hardware is 16ms (no matter if I 
use a timer or a thread+synchronize).
That at least explains the timing differences (but not the 
unresponsiveness of the full screen application under windows 7)

Luca Olivetti
Wetron Automation Technology http://www.wetron.es/
Tel. +34 93 5883004 (Ext.3010)  Fax +34 93 5883007

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