As a user I want a slanting tool

[nilsschmidt1337]

Maybe I should add a switch for "global", "local (lines)" and "local (manipulator)"??

Initial dialog text:

A tool that generates and applies a projection matrix from 2 or 3 lines to any selection.

There are two possibilies to use this tool:

a) Two-line variant

1. Create two lines with one common vertex.
   Example A: (red line = X axis, blue line = Z axis)
   2 4 0 0 0 1 0 0
   2 1 0 0 0 0 0 1
   Example B: (red line = X axis, green line = Y axis)
   2 4 0 0 0 1 0 0
   2 2 0 0 0 0 1 0

2. Select only these two lines in the 3D editor (LDPE will automatically calculate the matrix)

3. Select the element(s) which should be changed and open this tool again.

a) Three-line variant

1. Create three lines with one common vertex. One red line for the X axis, one green line for the Y axis, and one blue line for the Z axis.
   Example:
   2 4 0 0 0 1 0 0
   2 2 0 0 0 0 1 0
   2 1 0 0 0 0 0 1

2. Select only these three lines in the 3D editor (LDPE will automatically calculate the matrix)

3. Select the element(s) which should be changed and open this tool again.

Dialog after successful selection

• Set origin to center of the first axis pair (useful for rect-primitives)

The following matrix will be applied to your selection.

a b c x
d e f y
g h i z
0 0 0 1

OR

You haven't selected anything, but the following matrix is calculated based on 2 OR 3 axes.

a b c x
d e f y
g h i z
0 0 0 1

[nilsschmidt1337]

Closed with commit ff5ec0a.