# Plugin Transformatiion controled by 2-4 points

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Plugin Transformatiion controled by 2-4 points | Urmel_x | 06 Feb 21:44 |

### Plugin Transformatiion controled by 2-4 points

Hi all,

I'm a beginner in using mailing lists and in developing GIMP-plugins - but not a beginner in programming. I have developed a plugin for GIMP - tested under GIMP 2.8 and GIMP 2.10. I ask me if there any need for others of a pugin with following possebilities:

My plugin can transform a drawable by a transformation wich is defined by a pair of two to four marked points so that the transformation of the whole drawable transfer the position of every marked source-point to the position of the similar destination point. The whole drawable where transformed so that the set of two to four positions - normaly laying inside of the drawable - will laying after the transformation at the befor marked destination positions.

If you have used sets of four points - a perspectivic transformation will be calculated by the two sets of the four points wich you have marked in the drawable.Specialy the by four points defined quadrangle will be changed to the destination-quadrangle.

If you have used sets of three points - a affine transformation - a chain of translations, rotations, scaling and shrinking - will be calculated by the two sets of the four points wich you have marked in the drawable.Specialy the by three points defined angle will be changed to the destination-angle.

If you have used sets of two points - a linear transformation - a chain of translations, rotations and scaling - will be calculated by the two sets of the two points wich you have marked in the drawable.Specialy the by two points defined direction will be transfered to the destination-direction.

The sets of points where represented by a path wich you can choose from a list by starting the plugin.

If you use only one set of points (that means one path with 2 to 4 points) the plugin constructs a hiden set of points as destination so that the transformation align the lines between the source-points parallel to the coordinate-axis:

By marking two source-points the given direction will be transfered to a vertical or horizontal direction. There is no scaling - only rotation in the first source point.

By marking three source-points the given angle will be transfered to a right-angle and the legs to horizontal and to vertical.The length of the two angle-legs and the position of the second source-point will be unchanged.

By marking four source-points the quadrangle will be transfered to a square with horizontal and to vertical sides.The length of the two sides by the second source-point and its position will be unchanged.

By all the source- and destination-path (wich contains the source- and destination-points) keep unchanged.

I hope you can read and understand my horrible english. If any need of this plugin - where can I public this plugin?

Greetings,

Andreas from Germany