[Therion] ***UNCHECKED*** New symbols

[rsev at protonmail.com]

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Thursday, November 28, 2019 5:23 AM, Bruce Mutton <bruce at tomo.co.nz> wrote:

>
> 1.  May want to reconsider the insertion (0,0) point of some points (wheelchair, drip and camera), although they might be OK also.

The result shown in your "map -map-fg-gray - symbols centred on grid.pdf" file is exactly what I expected and wanted. What would you have in mind?

> 2.  Points gate, no-wheelchair, water-drip, and possibly human-bone, danger should probably allow the foreground/background colour to show through.

Of these I believe only gate should actually allow the background color to show through. I believe the others actually work better this way as I even created them with backgound color show through and changed them afterwards.

About the gate point: making background color show through is kind of a black magic in Metapost. As gate has several hollow spaces, it got harder than I thought it was worthwhile but it can definitely be done.

> 3.  Points with multiple speleothems do not handle rotation well.  I think the existing Therion stalactites and stalagmites suffer from the same problem.

You made 2 PDFs with rotated symbols. The first one has some symbols that seem off to me but the second one has the exact behaviour I want and expect. Was it created without any align option, isn't it?

As far as I can see, it's all related to the order you choose to apply the transformations. I used the align before the rotate. If you move the align to be done after the rotate the behaviour changes. Maybe you could test a little bit and propose a better order for the transformations after testing several use cases.

> 4.  The picture based symbols have no U: definition, so they crash Therion with metapost exit code – 2 if you try to align them.  They should have a reasonable U: parameter set.

I apllied the align parameter to several of them and got no error. Can you send a file where you see this issue?

> 5.  Points that can be aligned , have their (non-zero) rotation corrupted when they are both rotated and aligned.  You can see in the example that the speleothem points have been aligned bottom-right, when the th2 file says they should be aligned right).  This problem exists with all (almost) existing Therion points.  I have identified the cause and proposed a solution here https://therion.speleo.sk/wiki/metapost#symbol_sizing_and_positioning but my metapost skills are very basic, so no doubt it could be improved upon.

I'm not sure I fully understand your issue. The result for rotated and right aligned symbols seemed more intuitive to me when I inverted the align and the rotate transformations in symbols. I bet that would be a nice change but I wonder if you are talking about something more subtle that I have not fully understood yet.



Rodrigo