manual curve tool bug at white point

[Jeff Abrahamson]

Moving the white point (the top right point on the curve) to the left doesn't change the histogram as it should. It must be moved a bit down to have an affect. Small adjustments to the white point become hard, as do pure white point changes (akin to the "levels" dialog in gimp).

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: ufraw 0.18-2ubuntu1
ProcVersionSignature: Ubuntu 3.5.0-25.39-generic 3.5.7.4
Uname: Linux 3.5.0-25-generic x86_64
ApportVersion: 2.6.1-0ubuntu10
Architecture: amd64
Date: Wed Apr 10 04:55:50 2013
EcryptfsInUse: Yes
InstallationDate: Installed on 2010-08-16 (967 days ago)
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
MarkForUpload: True
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: ufraw
UpgradeStatus: Upgraded to quantal on 2012-10-23 (168 days ago)