Advanced ways to create guides in GIMP
Few days ago a user asked in a GIMP forum how to create a set of guides with an equal distance between the guides. Hence the new GIMP tutorial.
Guides are a great way to keep items aligned in your design without having to use the Align/Distribute tool all the time. You just drag an object (selection, layer or path), and it snaps to a guide line.
Indeed, by default GIMP is shipped with fairly simplistic scripts to deal with guides. But there is some interest in more sophisticated tools, and that request is met but some 3rd party extensions. Let's review them.
A minor note before we go: for reference on installation of .scm and .py files please read this add-ons management guide.
All scripts listed below with two exceptions will show up in Image → Guides submenu (see above).
Adding equally spaced guides
This is probably the most common scenario. There are several scripts or, rather, sets of scripts to do just that. The first script is called New Guides Every X Pixels.
Pick direction, set spacing in pixels between guide lines, and it will create equally spaced guides starting at 0 of an axis.
The principle of both is that it creates new guides at an equal offset starting at a user-defined point: the left side of an image, the right side of an image or the center of an image. H and V in the names refers to horizontal and vertical.
Each of them will keep creating new guides until it reaches border(s) of an image.
Finally, Grid (of Guides) is rather self-explanatory: it creates a grid of guides with user-defined amount of cells in both dimensions.
The predictable output is:
Adding guides in arbitrary positions
There are three options here. The first one are the two scripts shipped with GIMP by default, New Guide and New Guide (by Percent), if you can stand the excitement of repetitive calling the dialog to define a new value when you need multiple guides. The first one asks for a coordinate in pixel for a chosen dimension, the other one uses relative value, in percents from dimension's length.
A much better option is the Multiple Guides plug-in from the GAT tools set (this one is in Tools → Gimp-Atelier submenu):
The dialog is pretty much self-explanatory. Here is the output:
The other option is the Add Multiple Guides plug-in. For some reason the developer chose to stick to his native language which is German, so that the plug-in shows up in menu as Mehrere Hilfslinien setzen, but the UI is simple enough to understand:
The "prozentual?" checkbox to the left toggles percentage mode, "Hilfslinie" means "a guide line", the entry box is the entry box by any other name, and "horizontal/vertikal" combo box is hopefully self-explanatory too.
You can click Add button to remove a new guide to the stack, and Remove button deletes the last guide in the stack. The output from the example above is:
So the advance over the plug-in from GAT tools is that you can mix relative (percents) and absolute (pixels) units.
Of course, where would we be without common presets?
Border Guides script renders guides around border, but allows you to define an offset on both X and Y axis. A positive value (e.g. 5px) for both will render guides inside the page:
Center Guides script will do exactly what it says:
The output from the Add Rule Of Thirds guides plug-in is pretty much predictable as well:
The 10% Grid Guides script, accessible from the bottom of the View menu will render a 10×10 grid inside your image, also rendering guides around the page:
Finally, GAT tools come with a Guide Sets plug-in to render guides from a variety of presets: Center Cross, Rule of Thirds, Golden Ratio, Fields 3×4 and so on:
The output is:
You can also use Free Fields options and set amount of grid cells in both directions, up to 50 for both X and Y.
Thanks to various 3rd party scripts you can simplify creating new sets of guides. However these scripts and plug-ins are redundant to some extent.
I can see two possible solutions:
- Merge the existing scripts to match common use scenarios and ship them with GIMP.
- Create a native Scribus-like dialog to manage guides.
This could be a fancy little GSoC project, especially if angled guides were implemented as well (ask Joao S. O. Bueno for details).