A guide idf shape

[Anders Markvardsen]

Most known cases of guides are the following special case of a hexahedron: a start rectangular aperture which in a continued fasion changes into an end rectangular aperture.

This common guide shape is called a tapered guide (Peter Willendrup)

Suggesion is to let user add the following xml in an IDF:

<tapered-guide id="some id string">

<aperture-start height="" width="" />

<length val="" />

<aperture-end height="" width="" />

<centre x="" y="" z="" />

<axis x="" y="" z="" />

<tapered-guide>

By default <centre> is x="0", y="0" and z="0".

When <centre x="0", y="0" and z="0" > the centre is the middle of the of the guide (i.e. half way along guide in the middle).

By default <axis> is x="0", y="0" and z="1" and this is the direction of the guide. Then the height attribute is along y-axis and width along x-axis

Both <centre> and <axis> are optional for the user to specify

[Peter Parker]

Refs #7940 - Allow creation of "Guide" objects.

• Converts guide to hexahedron and uses pre-existing code to create shape.
• Updated schema.
• Added unit tests.

Changeset: ff0bae1cd1630f7ca4b8a847b85e6c862baba4e6

[Peter Parker]

Marking as complete.

To test:

• Create a new instrument file and make use of the implemented "guide" shape. The Wiki has information about how to create IDFs. I have added a section on guides to the page about the various available shapes.

• Load the new instrument file using LoadEmptyInstrument and view it via the Instrument Window. Ensure that any guides appear as you would expect.

• Make sure that the default values for axis and centre are used where they have not been specified.

• Check to see that reasonable changes have been made to the code and that the unit tests offer decent coverage.

[Peter Parker]

The following changes are needed:

• In the case where a user adds incorrect axis or centre values, the error messages are swallowed and default values are used. This is not ideal; if the user makes an attempt at these values but fails, then the shape should be ignored as if it did not have a default.

• Bounding boxes for guide shapes would ideally be created automatically. Have a look to see how this is done for the simpler shapes within the code, and try and do likewise.

[Peter Parker]

(In #7971) This ticket contains getOptionalShapElement(), which is required by two other tickets.

[Peter Parker]

Waiting for 7970 to be tested and merged into master.

[Gesner Passos]

Merge remote-tracking branch 'origin/feature/7940_guide_idf_shape'

Full changeset: ​6926e6fa24c1a2e47b00618ce616df36001b77b1

[Peter Parker]

Merge branch 'feature/7940_guide_idf_shape' into develop

Refs #7940

Conflicts:

Code/Mantid/instrument/Schema/IDFSchema.xsd

Changeset: e502b15ce251ebca7a789eb6e3e8a3e793b1d80c

[Peter Parker]

Note that the above commit is a merge into Develop that for some reason Trac failed to pick up the individual changesets. They were as follows, in chronological order:

• ec4cd4f2abb52781e94350eb595b5b8254faaa73
• afad9f9a73b3f9657f6bab36a24f36ce48d987a9
• 7b19363536da781bb9d90ea7d8987624d325f66e
• c8587936610cc4c00721b2a92119116fdee45fc0
• b216bb30267ab47757d1864b13c0225604609057

[Peter Parker]

To test, see comment 4.

Note:

• I have opened #8189 to create bounding boxes automatically for tapered guides (and hexahedrons).
• The <centre> tag is no longer defined as the middle of the shape, but as the middle of the start aperture.

[Samuel Jackson]

Merge remote-tracking branch 'origin/feature/7940_guide_idf_shape'

Full changeset: ​85ff8de7107cf65694ff9070d0f26ad65bc63596

[Samuel Jackson]

Despite my best efforts, I failed to break anything. The drawing, rotations and translations all work how I would expect them to work. Using very small number for widths/heights appear to work as well. The default values are also used when a centre and/or axis aren't specified. Code looks good too.

[Stuart Campbell]

This ticket has been transferred to github issue ​8785