18.14. Environment

Environment Preferences

This page lets you customize the amount of system memory allocated for various purposes. It also allows you to disable the confirmation dialogs that appear when you close unsaved images, and to set the size of thumbnail files that GIMP produces.

Options

Resource Consumption

Minimal number of undo levels

GIMP allows you to undo most actions by maintaining an "Undo History" for each image, for which a certain amount of memory is allocated. Regardless of memory usage, however, GIMP always permits some minimal number of the most recent actions to be undone: this is the number specified here. See Undoing for more information about GIMP's Undo mechanism.

Maximum undo memory

This is the amount of undo memory allocated for each image. If the Undo History size exceeds this, the oldest points are deleted, unless this would result in fewer points being present than the minimal number specified above.

Tile cache size

This is the amount of system RAM allocated for GIMP image data. If GIMP requires more memory than this, it begins to swap to disk, which may in some circumstances cause a dramatic slowdown. You are given an opportunity to set this number when you install GIMP, but you can alter it here. See How to Set Your Tile Cache for more information.

Maximum new image size

This is not a hard contraint: if you try to create a new image larger than the specified size, you are asked to confirm that you really want to do it. This is to prevent you from accidentally creating images much larger than you intend, which can either crash GIMP or cause it to respond verrrrrrrry slowwwwwwwwly.

Image Thumbnails

Size of thumbnails

This options allows you to set the size of the thumbnails shown in the File Open dialog (and also saved for possible use by other programs). The options are "None", "Normal (128x128)", and "Large (256x256)".

Maximum filesize for thumbnailing

If an image file is larger than the specified maximum size, GIMP will not generate a thumbnail for it. This options allows you to prevent thumbnailing of extremely large image files from slowing GIMP to a crawl.

Saving Images

Confirm closing of unsaved images

Closing an image is not undoable, so by default GIMP asks you to confirm that you really want to do it, whenever it would lead to a loss of unsaved changes. You can disable this if you find it annoying; but then of course you are responsible for remembering what you have and have not saved.

Size of thumbnail files

Here you can set the size of thumbnail files that GIMP generates. Regardless of this value, GIMP will still be capable of reading thumbnail files of any size.