2.7. To Edit the Preferences

You can change the current settings using Edit->Preferences:

Figure 2-6. Preferences Dialog

2.7.1. Global settings

GChemPaint has two global settings:

Compression level

The compression level used when saving native files. If not 0 the file will be compressed using gzip.

Invert wedge hashes

If set, the wedge hashes bonds will follow the usual convention which put the narrow end at start and the large end at the farest end. Default convention in GChemPaint is just the inverse, because it is more consistent with perspective rules.See the Stereo bond tools section for more information.

2.7.2. Editing Themes.

Each document has an associated theme. When a document is opened, GChemPaint searches if a theme already exists with the same name and the same settings. If found the existing theme is used, otherwise a new theme is added to the themes set and used only for this file. It is possible, although not recomended, to change the theme associated with the file using it's Properties Dialog.

When the Preferences Dialog Box is opened, the active document theme is selected.

For each theme, the various settings are spread on several pages. General settings.

This page presents the settings which did not fit well elsewhere.


The name of the theme. This name can be changed for user define themes and themes specific to a file. Not for the default Theme or other pre-defined ones.


Scale used to convert real distance to canvas distance expressed in pm per pixel.

General padding

Padding used around text objects such as atoms, texts and other typographic signs in pixels.

Object padding

Default padding in pixels added between consecutive objects during an alignment operation.

Stoichiometry padding

Extra padding between a stoichiometric coefficient and its associated molecule in pixels.

Sign padding

Padding between a '+' sign in a reaction equation and reactants symbols in pixels. Arrows related settings.

Figure 2-7. Arrows Page


Default arrow length (in pm just like bond lengths). Changing this parameter will have no effect on the lengths of exisiting arrows.


Arrow line width (in pixels).


Distance in pixels between two parallel lines (either two arrows or one arrow with two lines).


Padding added at each end of an arrow (in pixels).

Arrow head A

Distance in pixels from tip of arrowhead to center.

Arrow head B

Distance in pixels from tip of arrowhead to trailing point, measured along shaft.

Arrow head C

Distance in pixels of arrowhead trailing points from outside edge of shaft. Atoms related settings.

Figure 2-8. Atoms Font Page

Using this property page, it is possible to select the font used for atoms and other residues.

Figure 2-9. Atoms Extra Page

Charge sign size

The size in pixels of a localized charge sign, including the surrounding circle. Bonds related settings.

Figure 2-10. Bonds Page


Default bond length (pm). Changing this parameter will have no effect on the lengths of exisiting bonds


Default angle between two consecutive bonds in a chain.


Bond line width (in pixels).


Distance in pixels between two lines representing a multiple bond.

Stereo bond width

Width in pixels at the largest end.

Hash width

Width of hashes in pixels.

Hash distance

Distance between hashes in pixels. Text related settings.

Figure 2-11. Text Page

This font selector gives the default font selected when creating a new text object, unless an other font has been selected in the text tool property page.