Bug 150674

Summary: turn of live update of preview when moving points in curves dialog or in histogram
Product: [Applications] digikam Reporter: Mikolaj Machowski <mikmach>
Component: Plugin-Editor-CurvesAssignee: Digikam Developers <digikam-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: normal CC: caulier.gilles
Priority: NOR    
Version: unspecified   
Target Milestone: ---   
Platform: Compiled Sources   
OS: Linux   
Latest Commit: Version Fixed In: 0.9.4

Description Mikolaj Machowski 2007-10-10 16:44:29 UTC 
Version:            (using KDE Devel)
Installed from:    Compiled sources
OS:                Linux

It applies to all plugins with histogram or curves manipulation.

When moving points of histogram/curves digiKam tries to make live update of preview. It takes much of resources and computer neither really succeeds in updates of preview nor reacts smoothly for mouse movements preventing precise settings.

Maybe my machine isn't up to date (Sempron 2200, 756M RAM) but I believe it may affect also many newer computers.

I am leaving this as a bug, not wish, because IMO it makes comfortable usage of program very hard. GIMP - dedicated graphics operation program - doesn't make live update, Pixel also doesn't do this.
Comment 1 Mikolaj Machowski 2007-11-01 19:19:32 UTC 
New Gimp 2.4 now has digiKam behavior. Don't like it but should be noted :)
Downgrading to Unconfirmed.
Comment 2 caulier.gilles 2008-03-20 15:00:38 UTC 
Mik, 

there is a timer of 500ms which is used to delay render when you change settings (from slider for ex.). This prevent multiple render at the same time when you change a value. This is not enough ?

Gilles
Comment 3 Arnd Baecker 2008-03-20 17:27:17 UTC 
Of course, timer values are somehow system dependent, so this can be problematic.
Question: is the curves operation for the preview done on a small bitmap?
(If yes, it should be reasonably fast ... ;-).
Comment 4 Mikolaj Machowski 2008-03-20 17:58:27 UTC 
Hmm. Don't know what changed recently but it feels much faster and using of curves is quite comfortable.

Closing as WORKSFORME