In this tutorial, I’ll be showing you how to transform paths using GIMP. This is a very easy task to accomplish and can help expand your skill-set for photo editing and graphic design when working in GIMP. It is useful whenever you need to change the shape, position, orientation, size, etc. of a path after you have already drawn it.
1. Draw Your Path
The first thing you’ll need to do, of course, is draw your path. You can do this using the Paths tool in GIMP – which you can access via the GIMP Toolbox (red arrow in the photo above) or by using the “b” shortcut key. (The “b” stands for Bezier Curve.)
Click on your image to begin drawing your path. Clicking will add nodes (green arrow in the image above), and between each node will be a line segment. If you are not familiar with how to use the paths tool, I recommend checking out my Master the Paths Tool tutorial for an in-depth look at this highly useful tool.
In my example, I’m drawing a path around an hourglass. The size of the photo of this hourglass is 1280 x 853 pixels (you can see the dimensions of the image outlined in green in the photo above). However, I also have a larger version of this photo that is 1920 x 1280 pixels (denoted by the red arrow in the photo above – this is the tab for the second photo composition I have opened in GIMP).
GIMP Basics Tip: Simply go to File>Open to open images into GIMP.
Let’s say, hypothetically, that I finished drawing my path around the hourglass object, only to realize that I want to use the larger version of the photo. I don’t want to have to redraw my entire path around the object, so what I can do is copy the path from the smaller image to the larger image, then scale the path up. I’ll also need to reposition the path using the Move tool so that it properly outlines the hourglass object.
There are plenty of other examples for wanting to scale, move, flip, or rotate a path – this is just one example.
So, once my path is drawn, I’ll need to copy the path from my current composition to my new composition. To do this, I’ll navigate over to my “Paths” tab (to the right of my Layers tab – red arrow in the above image) and click on the “Unnamed” path (green arrow).
Just like a layer, you can change the name of your path by double-clicking on the current name and typing in a new name. I renamed my path “Hourglass” (red arrow in above image). Hit the enter key to apply the name.
Now, right-click on the path and go to “Copy Path” (red arrow in the image above).
Navigate over to the larger image (red arrow in the image above) and go to “Paste Path” (green arrow). This will paste your path in the Paths tab.
Click the “Show/Hide” icon to view your path in the new composition (red arrow in the image above).
Because the new image is larger, the path we drew in our previous composition is now too small and in the wrong location (green arrow in the image above). We will need to use a combination of transform tools to get it in the right spot.
2. Change the Mode of Your Transform Tool
Now that our path is in our new composition, I’ll use both the move tool and scale tool to adjust the path so that it once again outlines the hourglass.
I’ll start with the move tool, which I can activate by clicking on it in the Toolbox (red arrow in the photo above) or by using the “m” shortcut key on my keyboard.
Once I have my move tool selected, under the tool options I’ll select “path” for the mode (green arrow) – this is the third option listed here (usually, by default, it is set to “Layer”). This mode means my move tool will now move paths rather than layers.
Once the move tool is set to paths, I can click on the path with my move tool and drag it anywhere on the composition. I’ll drag the path so that it is around the same area as the larger hourglass.
Now, I’ll use the “shift+s” shortcut key on my keyboard or select the Scale tool from my toolbox (red arrow in the image above). Like the move tool, and any transform tool for that matter, we can also change the mode from “Layer” to “Path” in the Tool Options (green arrow).
Once this transform mode is selected, I’ll click on the path with the scale tool. This will bring up transform handles around my path.
I’ll click and drag one of the transform handles (preferably one of the corner handles – blue arrow in the image above) and drag my mouse outwards.
I can also use the four boxes in the center of the path to move it slightly in any direction (red arrow in the image above).
Once it is in place, I’ll hit the “Scale” button (blue arrow).
3. Make Final Path Adjustments and Change Transform Mode Back to Default
I recommend zooming in on your path (hold ctrl key and use your mouse wheel) to make sure it is properly aligned to your object. In my case, I used the move tool (“m” shortcut key on your keyboard) once again to make a minor correction to the position of the path until it was aligned (red arrow in the image above).
Once your are done, I recommend changing the mode of your transform tools back to “Layer” (blue arrow) to make sure you don’t get confused when trying to transform a layer in the future (if the mode is set to path, the tool won’t work when trying to scale a layer, for example – you’ll get an error message in the status bar. Since transforming a layer is more common than transforming a path, I change my transform tool modes back to Layer when I’m done with them).