New navcon text format, with converter, fix #1772

[illwieckz]

Introduce a new navcon text format.
Make the engine loads both old and new format and write new format.
Add a navcon converter to convert existing navcon files to the new format.

Fix #1772.

The output format is a text format, all numbers are written as integers as float precision is believed to be overkill.

Output format is like:

navcon 3
x1 z1 y1 x2 z2 y2 rad flags areas dirs
x1 z1 y1 x2 z2 y2 rad flags areas dirs

Example:

$ hexdump -Cv ~/.local/share/unvanquished/game/maps/plat23-level4.navcon
00000000  02 00 00 00 02 00 00 00  56 c5 7e c3 00 00 00 c0  |........V.~.....|
00000010  b9 bc e4 44 e1 59 0a c3  28 6c c9 3d 48 65 dc 44  |...D.Y..(l.=He.D|
00000020  99 f8 1e 43 00 00 00 c0  91 76 0c 45 9f 45 a3 43  |...C.....v.E.E.C|
00000030  4c 6f e1 c2 24 12 0c 45  00 00 48 42 00 00 48 42  |Lo..$..E..HB..HB|
00000040  01 00 01 00 3f 3f 01 00  00 00 00 00 00 00 00 00  |....??..........|
00000050

$ ./convert-navcon ~/.local/share/unvanquished/game/maps/plat23-level4.navcon > plat23-level4.navcon
Converting /home/illwieckz/.local/share/unvanquished/game/maps/plat23-level4.navcon
Converting from format version 2 to 3
Converting 2 connections

$ ./convert-navcon plat23-level4.navcon
Not converting plat23-level4.navcon
Already in format version 3

$ cat plat23-level4.navcon
navcon 3
-254 -2 1829 -138 0 1763 50 1 63 1
158 -2 2247 326 -112 2241 50 1 63 0

$ du -b ~/.local/share/unvanquished/game/maps/plat23-level4.navcon plat23-level4.navcon
80	/home/illwieckz/.local/share/unvanquished/game/maps/plat23-level4.navcon
80	plat23-level4.navcon

[sweet235]

lgtm

[slipher]

userid seems to be unused (always 0) so you could omit that from the text format.

[illwieckz]

userid seems to be unused (always 0) so you could omit that from the text format.

I stripped it.

Anyway, that's fun:

$ du -b ~/.local/share/unvanquished/game/maps/plat23-level4.navcon plat23-level4.navcon
80	/home/illwieckz/.local/share/unvanquished/game/maps/plat23-level4.navcon
80	plat23-level4.navcon

[illwieckz]

I added a patch to make the game load both the old and new format and write the new format instead of the old one.

	old	new
read	yes	yes
write	no	yes

This is based on a shameless copy-paste of the layout parser writer (which uses a similar format), despite being so C89 and featuring a lot of cargo cult, it works.

[illwieckz]

I added the ability to pass -i to the converter to rewrite a file in place.

[illwieckz]

I added some extra code to make sure the parser doesn't read missing number of a line from the next line, also the sscanf calls detect if there is missing fields or too much fields.

[illwieckz]

I added a commit to delete the extra debug print, that commit is easy to revert for re-enabling debugging.

[illwieckz]

Some navcons ready to import from https://github.com/sweet235/navcon

• import navcons UnvanquishedAssets/map-chasm_src.dpkdir#8
• import navcons UnvanquishedAssets/map-parpax_src.dpkdir#14
• import navcons UnvanquishedAssets/map-perseus_src.dpkdir#7
• import navcons UnvanquishedAssets/map-thunder_src.dpkdir#5
• import navcons UnvanquishedAssets/map-vega_src.dpkdir#9