Raise the 127-icons-at-once limit for displaying files

[c0mmander8]

Eliminate, or at least raise, the 127-icons-at-once limit for displaying files, especially if the system has additional memory available.

[inexorabletash]

This would require a complete rewrite. Not practical in this project.

[c0mmander8]

What about doing so within the existing 128K memory footprint?

[inexorabletash]

Many, many parts of the codebase assume at most 127 icons - the guts of the icon painting logic ("IconTK"), the per-window tables listing the icons present, icon id to address mapping, and code throughout that assumes that high bit set = invalid icon. Each icon also requires 25+32 bytes (IconEntry + FileRecord) - which admittedly is a little silly as the name is duplicated between those structures. Those two data structures are split across LC 4k banks, which have limited space - the FileRecords consume one entire 4k bank!

I suspect a total rewrite would be easier than retrofitting the existing code. Which is not a bad idea, it's just beyond the scope of this project.

[c0mmander8]

Please reopen this issue. I still think that this issue is an important issue to be implemented because this would greatly increase the usability of Apple II DeskTop.

[inexorabletash]

Handful of notes about the challenges here to just double the limit to 255 icons, for memory buffers and logic changes:

• need 2x the room for FileRecord and IconEntry (icon_entries) storage
  • note that name is stored redundantly in each (16 bytes!)
    • Use AuxLC2 $D000 for 256x16 byte names
    • IconEntry needs at least 4 (x/y) 1 (icontype) 2 (flags/window) = 7 bytes
    • FileRecord needs at least 3 (type/aux) 2 (blocks) 4 (date) = 9 bytes
• need 2x the size for tables:
  • DeskTop's icon_entry_address_table x2
  • IconTK's icon_ptrs x2
    • Dedupe the above two items (e.g. move to LC, accept it'll be exposed)
  • DeskTop's selected_icon_list
  • IconTK's highlight_list
    • Dedupe the above two items (e.g. move to LC, accept it'll be exposed)
  • DeskTop's window_entry_table
  • DeskTop's free_icon_map
    • Compress to a bit map (1/8th the size)
  • DeskTop's cached_window_entry_list
  • IconTK's icon_list
• Return values from drag/drop (high bit signals window vs. icon)
• Anything that uses $FF/BMI for failure (vs 0)