Fix labelling and position of HCP grains in IPF

[rhysgt]

HCP orientations are now plotted onto the IPF in the correct place. There is an option to choose between triangle facing down (like aztec) and triangle facing up (like mtex).

[rhysgt]

This breaks ifp colour plotting so not a good approach. maybe just changing the labels is fine.

[mikesmic]

Have you checked the IPF colouring for cubic and hex crystals when you fixed? I fixed and checked IPF point plotting for both but didn't account for breaking colouring at all.

[rhysgt]

I checked hex and did a quick patch cb858f4. I'll check cubic also and get back to you.

[rhysgt]

@mikesmic I've added a test for Quat.calc_ipf_colours based on values that I know are correct. Do you have any suggestions on how to improve? I have also added a patch to fix the cubic\hex ipf colours, but could do with improving the logic. Currently, I pass triangle='ipf_map', which uses the same beta_range as before.

[mikesmic]

Can't we just change the directions the colour components are calculated against and use the 'up' convention we already have? Test looks good. Could you add a few more cases, maybe with crystal directions other than <100> and then I'll try to make the colours work

[rhysgt]

Sounds good. Added an additional ori and some directions. Something in file_readers is breaking tests on Python <=3.10 also.

[mikesmic]

I know what the issue is with the file readers, I'll fix later.

[mikesmic]

I've updated the RGB directions so the extra IPF triangle convention isn't needed. The only thing I didn't check is changing the hex orthonormalisation convention from hkl to tsl. Not sure what happened with that before.

[rhysgt]

I was thinking of adding a test in the EBSD class also to check for the correct result for ipf x,y,z colours and positions, using the test ebsd data? Would also need one for hcp and perhaps non-OI data as well? Would that do the job?