INDI alignment infrastructure / Development blog: Recent posts

The git repository now contains a reasonably complete implementation of the straw man. It needs testing with real alignment data.

Here is the new straw man.

1. Implement a new "alignment_layer" driver. This will locally connect (same server) to a user specified driver as a client and then re-publish all the properties that that driver publishes along a with additional properties of its own for management purposes. In general if a client(user) modifies one of the republished properties the alignment layer will pass that property down to the underlying driver unchanged. The same will apply in the reverse direction, i.e.properties chnaged by the underlying driver will be passed up unchanged to any clients. The only exception to this will be controlled by two property names defined by the client in the alignment layers additional management properties. These names must match numeric coordinate properties published by the lower layer driver. I will refer to these names as the upper layer mapping and the lower layer mapping. They can be the same property name. If the alignment layer sees a new value sent by the client which matches the name of the upper layer mapping it will take the coordinate value, apply an affine transformation to it, and send it down to the lower layer driver via the property named in the lower layer mapping. The same will happen in reverse, i.e. if the alignment layer sees a new value sent from the lower layer driver for a property whose name matches the lower layer mapping, it will appply an affine transformation to it (usually the inverse of the downward transformation), and pass it on up to the client via the property named in the upper layer mapping. The transformation functions will be handled by the class library mentioned below. The alignment layer will expose the alignment point database functionality of that library via additonal management properties.... read more

The email that started this off is attached below. I have chopped the originbal straw man off the end as the design has deviated significantly from that!

Hi Jerry,

I have finally got round to reading your post in detail. I must admit I
have been getting a bit alarmed at the way this thread has been going. I
suppose that I somewhat to blame for that as I did not clearly state
what my starting parameters were. My idea was to produce a very
simplified alignment solution for "recreational astronomy" using a
simple AZ goto scope. I am not as mobile and flexible as I used to be
and I find aligning a small scope through the eyepiece a real pain.... read more