eriktim / qgsaffine

Perform Affine transformations (translation, rotation, scale) on vector geometries.

qgsAffine: Affine Transformations

Apply affine transformations to selected geometries.

This Quantim GIS (QGIS) plugin performs affine transformations on layers or a group of features.

Concept

For those infamiliar with affine transformations, here is the basic concept.

A point (x,y) can be tranformed to a new point (x',y') by:

x' = a * x + b * y + tx
y' = c * x + d * y + ty

where tx and ty are the translations in the x- and y-direction, resp.
a, b, c and d form the transformation matrix

    | a  b |
A = |      |
    | c  d |

that determines the rotation and scaling.

a, b, c, d, tx and ty are the variablesthat can be changed in the plugin.
Details on how to find the correct values for your case can be found anywhere on the Internet.

Defaults

By default, the translations are zero and T = I (the identity matrix), i.e.

x' = 1 * x + 0 * y + 0 = x
y' = 0 * x + 1 * y + 0 = y 

qgsaffine's Issues

Strange Behaviour on QGIS 2.16.3

Hi,

There's something really strange happening on QGIS 2.16 and further.

Translations appears not to be completed until the view on canvas is completly updated. which can result in deformations of parts of polygons.

EG:

Works fine on 2.14.6!

Transformation to keep the shape and change the area - scalling

What parameter should I use to keep the shape of the object and scale the area to say x 2 time, or x 3 time.

Fails to install on QGIS 3.2.0-Bonn

An error occurred during execution of following code:
pyplugin_installer.instance().installFromZipFile(r'C:\Users<UserName>\AppData\Local\Packages\Microsoft.MicrosoftEdge_8wekyb3d8bbwe\TempState\Downloads\qgsAffine-master (1).zip')

traceback.print_exception() failed

Python version:

QGIS version:
3.2.0-Bonn 'Bonn', bc43194061

Python path:

UnicodeEncodeError

Great plugin :-)
Please delete the test line print vlayer.name ()
This crashes Unicode characters in the Layername.

  File "C:/Users/...../.qgis2/python/plugins\qgsAffine\qgsAffine.py", line 124, in doaffine
    print vlayer.name()
UnicodeEncodeError: 'ascii' codec can't encode character u'\xe4' in position 12: ordinal not in range(128)

Thank's

Add option to change rotation/translation/scale separately

qgsAffine appears under Layer menu

qgsAffine plugin appears under "Layer" menu, instead of "Vector".

I have an italian version of 2.8.1-Wien, but I tested also setting in English US language, and nothing changes. Plugin version is 1.0.1

Moreover, switching off and on the plugin, it appears duplicated (or more) in (Layer) menu.

Add .README

Add readme with a short documentation & tutorial

Build script

Remove auto created files. Add build script.