Improve ordering of volume icons

[inexorabletash]

Volume icons are placed on the DeskTop according to the position in ProDOS's DEVLST, gaps and all. This is stable for a given system configuration, but is non-intuitive. ProDOS's order is also... curious, e.g. ending up with slots ordered 3, 6, 2, 7, etc, which can make for odd placement. Different versions of ProDOS also order the devices differently, especially w/ SmartPort remapping.

A handful of options:

• Ignore gaps: devices retain the ProDOS order but are densely positioned, starting at the top left of the screen.
• Custom ordering: enumerate in an order that puts e.g. S7D1 at the top left, since that's most likely to be the boot device these days on systems with mass storage. I don't know of an order that would please everyone, though.
• Both (this is my preference)

The benefit of retaining gaps is that the placement on a given system is constant, regardless of the state of removable disks. That may be too subtle for anyone to care about, though.

Enumeration of devices is done in DEVLST order (look for places that call create_volume_icon). Retaining this, either ignoring gaps or custom ordering is straightforward: to ignore gaps, use # of volume icons as index into coords table; to do custom ordering, use the DSSS nibble as an index into an ordering table.

Doing both requires more thinking.

[mgcaret]

A handful of options:

Another option would be (but more complex): Order new devices by one of those methods, afterwards remember where the user dragged them and consistently place them there.

I actually prefer the Finder's method of starting from the upper right and going down in columns.

ProDOS's order is also... curious, e.g. ending up with slots ordered 3, 6, 2, 7, etc

The order is actually the opposite of that, from ProDOS' perspective, the RAM disk is last. The DEVLST is used to search for volumes in the forward order (or, that is the intent in most ProDOS versions), making the slow Disk IIs (almost) the last thing it examines for a requested volume. The RAM disk is last because it's not supposed to be installed if there are already 14 available devices, though some versions of ProDOS don't get this right.

Where slot 2 is positioned depends on what, exactly, is in slot 5. If slot 5 has more than 2 devices, then slot 2 appears immediately after it. The whole thing is somewhat complex for various reasons, but mostly because mirrored ProDOS block devices only work one way (the firmware looks to see if the requested slot is this slot-3) and must be installed first, and mirrored SmartPort devices are installed just before the Disk IIs are.

MG

[inexorabletash]

Thanks!

(Re: slot 3 - I was looking at the RAM.SYSTEM-provided device, which gets inserted at the start)

As a quick fix I may just enumerate in reversed order and skip gaps. At least, that'd make sense on my machine. :)

[inexorabletash]

Hrm, swapping enumeration order was a bit tricker than I thought. I might land this:

;;;  +-------------------------------------------------+                                                   
;;;  |                                                 |                                                   
;;;  |                                           S7D1  |                                                   
;;;  |                                                 |                                                   
;;;  |                                           S7D2  |                                                   
;;;  |                                                 |                                                   
;;;  |                                           S6D1  |                                                   
;;;  |                                                 |                                                   
;;;  |                                           S6D2  |                                                   
;;;  |                                                 |                                                   
;;;  |                  S1D2    S1D1    S4D2     S3D1  |                                                   
;;;  |                                                 |                                                   
;;;  |  S4D1    S2D2    S2D1    S5D2    S5D1    Trash  |                                                   
;;;  |                                                 |                                                   
;;;  +-------------------------------------------------+                                                   
                                            

[inexorabletash]

Icons are now enumerated in reverse-DEVLST order, so no gaps. Order is still: down the right, then across to the left, then one more row above that:

+-------------------------+
|                     1   |
|                     2   |
|                     3   |
|                     4   |
|        13  12  11   5   |
| 10  9   8   7   6 Trash |
+-------------------------+

I could be convinced to make it three columns instead, but the logic for this current arrangement is compelling to me.