Here you find some Gimp plugins to transform paths. To
get the plugins, do:
## Download

- At the bottom of this page there is the Download button. Clicking it you get one .ZIP file. Unzip it and put the python file it contains in your Gimp's plug-ins folder and restart Gimp.
- This registers in your Gimp the plugins
**Transform a path by an affine map****Transform a path by a Bezier arc****Transform a path by a Moebius map**(actually a plugin and three further variations)**Transform a path by a Bezier arc quadrilateral**(an easy version and an advanced version)**Fit a path in a triangle****Fit a path in a convex quadrilateral****Convert a path to polar coordinates****Transform a path by exponential map**- To find the plugins in Gimp, go to the Paths tab and right-click the
path you are going to transform. This opens a pop-up window. At the
bottom follow the link

and choose from the transformations.__Tools > Transformations > ...__

**Transform a path by an affine map**requires three input paths:*The path you are transforming*(the right-clicked one).*Base*. A path which should have 1-3 anchors in one stroke.*Target*. A path which should have at least as many anchors as the*Base*.**Transform a path by a Bezier arc**requires four input paths:*The path you are transforming*(the right-clicked one).*Base*. A path with two anchors in one stroke.*Target*. A path with two anchors in one stroke.*Shaper*. A path with two anchors in one stroke.**Transform a path by a Bezier arc quadrilateral:**The advanced version*The source path you are transforming*(the right-clicked one).*Shaper*. A path with four anchors in one stroke.*Reference box*. A path with four anchors in one stroke. But there are built-in choices, such as the bounding box of the source path.*Target box*. A path with four anchors in one stroke.**Transform a path by a Moebius map**requires three input paths:*The path you are transforming*(the right-clicked one).*Base*. A path which should have 3 anchors in one stroke.*Target*. A path which should have 3 anchors in one stroke.- It is conformal.
- It sends circular arcs onto circular arcs.
- But here "circle" includes straight lines (circles with infinite radius). Hence, the map sends a straight line to a circle (or occasionally to another straight line).
- The map has normally one
*pole*, a point which is sent to infinity. If the pole is on the path to be transformed or in its close vicinity, the plugin may fail. - Another special point is the so-called
*inverse pole*. It is the pole of the inverse map; in other words, it is the point to which the infinite point will be sent. **Fit a path in a triangle**takes as input the path to be transformed and another path in the form of a triangle. The first path is fitted in the triangle by means of a mapping called*dilation*(translation and scaling). The path will not be distorted.**Fit a path in a quadrangle**works similarly, exceptthat instead of a triangle it uses a convex quadrangle, and that the mapping is a*projective transformation*. Consequently, the path is also distorted. Further, this plugin is not exact but does an approximation. The user has option to choose the level of the approximation (algorithm). In addition, the user can tweak the operation by drawing a*reference box*(a quadrangle) roughly around the input path. Default uses the bounding box.**Convert a path to polar coordinates**imitates Gimp's filter__Distorts>Polar coordinates__but this plugin is applied to a path rather than an image. It takes as input one path. It should be easy to experiment with, starting with the default values. A remarkable feature is that straight lines are mapped onto Archimedean spirals, or as special cases onto straight line or circles.**Transform a path by exponential map**is very similar to*To polar coordinates*but it performs complex exponential map (the plane is viewed as the complex number plane). It takes as input one path and two angles: alpha and gamma. Instead of Archimedean spirals, straight lines are generally mapped onto logarithmic spirals.

If the

What that "somehow" means is not described here. We mention only that if the plugin is applied with default inputs (the tweaks A=0, B=1) to transform the

It should be stressed that the map is

This plugin is rather similar to the previous one. But this map is