Using 1.5.0b49: Open two copies of a current development build of NetBeans.

Start one with -J-DuseGtk=true
Start the other normally.

Maximize both and front the GTK L&F one.

Using ALT-TAB, switch to the other one.
Notice the entire main window paints gray, and stays that way for 1/4 to 1/2 second; then it paints.

Now switch back to the one using Metal.
The window repaints 3-4 times faster than the GTK one.


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The painting with GTK L&F is generally slower than with Metal. This is the case with both Bluecurve theme (RedHat default) and with Blueprint theme (Sun's JDS default). Here are exact numbers I measured under the following conditions:

* Dell Precision 220, PIII 800MHz, 512MB RAM, Red Hat 9, Gnome
* Blueprint theme
* jdk 1.5.0-beta2-b51
* SwingSet2 demo and netbeans trunk build 200405171800
* times in milliseconds
* each action measured three times in a row

SwingSet2 demo:
===============
[ Main Menu Items ] - [ Metal L&F ] - [ GTK L&F ]
File - 122, 99,99 - 147, 119, 127
Look & Feel - 123, 79, 108 - 138, 135, 112
Themes - 77, 54, 111 - 142, 132, 122
Tooltip - 79, 91, 23 - 100, 77, 50

[ Windows ] - [ Metal L&F ] - [ GTK L&F ]
Switch to Source Code tab - 1518, 96, 15 - 1695, 185, 204
Maximize Frame 0 - 211, 149, 107 - 708, 480, 416
Show About dialog - 503, 166, 153 - 440, 351, 388
Close About dialog - 295, 241, 244 - 600, 521, 522

Netbeans:
=========
[ Main Menu Items ] - [ Metal L&F ] - [ GTK L&F ]
File - 168, 103, 95 - 245, 140, 140
Edit - 172, 106, 99 - 247, 111, 117
View - 56, 57, 55 - 99, 89, 89

[ Windows ] - [ Metal L&F ] - [ GTK L&F ]
Options dialog - 707, 452, 326 - 1806, 851, 841
New Project wizard - 1169, 496, 374 - 1442, 876, 651
Versioning toolbar ON - 592, 156, 181 - 2315, 1025, 995
Versioning toolbar OFF - 186, 144, 155 - 986, 1057, 1010

FYI, here are links to Issuezilla bugs entered against Netbeans IDE:
http://www.netbeans.org/issues/show_bug.cgi?id=42916
http://www.netbeans.org/issues/show_bug.cgi?id=42930
http://www.netbeans.org/issues/show_bug.cgi?id=42933

###@###.### 2004-05-20