(svn r4229) [elrail & autoreplace] Always show compatible rail vehicles in the left list, and only the selected rail type in the right list, to
allow converting electric engines to non-electric.

(svn r3564) Several smaller changes:
- Don't treat non-booleans as booleans
- Reduce variable scope
- Bracing
- Use DeMorgan's law to make conditionals easier to read
- if cascade -> switch
- Replace some magic numbers by symbolic names
- Avoid assignments within other statements

(svn r3535) -Feature: [autoreplace] allow autoreplacing of train wagons
currently ALL available wagons are displayed in the right menu in the replace window
however the replacement will only be done if the new wagon can be refitted to carry same cargo as the old one is currently carrying

Since the standard vehicles do not have any valid wagon replacements, this feature can only be used when using newgrf sets

(svn r3396) - Autoreplace changes:
- Change fixed array per player to a single pool. This avoids future problems
with vehicle numbers and decreases savegame size. Engine replacements from
previous savegames will be lost.
- Move engine replacement code from players.c to engine.c.
(thanks to blathijs for rewriting this)

(svn r3218) -Feature: Multiheaded train engines will now stay in the same train
This means that any user attempt to remove a rear engine will tell the user to move the front engine instead
This fixes the assert when moving multiheaded engines (introduced in r3144)
Note: to make old savegames use this feature, some engines might be turned around in order to link engines in pairs

-Codechange: train subtype is now a bitmask
This allows fast access to info like if it is a wagon or engine and if it is in front and so on
Note: savegame version bump

(svn r3181) -Bracing
-Indentation
-Whitespace
-DeMorgan's Law
-Test with NULL or 0 for non-booleans
-'\0' instead of 0 for chars
-Remove redundantly redundant comments (like DoFoo(); // Do foo)
-Join multiple short lines with a single statement
-Split single lines with multiple statements
-Avoid assignments in if

(svn r3155) -Feature: [autoreplace] autoreplace can now remove cars from too long trains
-Trains will now remember the length of stations it visits and sell cars
when being autoreplaced if they became too long
-If it needs to remove cars, then it starts from the front and sells
all it can find until the train is short enough
-This only works for trains, that knows the station length of the route
so a full uninterrupted run is needed
-a train needs 1-2 runs to detect if the shortest station is expanded
-This feature can be turned on and off in the train replace window
and each company can have it's own setting
-NOTE: minor savegame version bump

(svn r3081) -Codechange: [autoreplace] complete rewrite of autoreplace
this is a complete rewrite, that makes use of existing commands like build and sell
this means that multiheaded train engines are replaced correctly

(svn r3078) Some more stuff, which piled up:
- const, whitespace, indentation, bracing, GB/SB, pointless casts
- use the trinary operator where appropriate
- data types (uint[] -> AcceptedCargo, ...)
- if cascade -> switch
- if (ptr) -> if (ptr != NULL)
- DeMorgan's Law
- Fix some comments
- 0 -> '\0', change magic numbers to symbolic constants

(svn r2974) -Fix: Drag and drop selection on drop down boxes didn't select correct item when some items were hidden.
-Separate disabled and hidden masks in drop downs to support both hidden and disabled items.

(svn r2962) - const correctness for all Get* functions and most Draw* functions that don't change their pointer parameters
- change a lot of byte player types to PlayerID
- beautify header files, same "#endif /* filename */" ending

(svn r2817) -Codechange: [autoreplace]: moved autoreplace and autorenew to serverside
-This means that one company can only have one setting for renew and replacing
more clients will not fight due to different settings anymore
-This is a needed step in the line to fix autoreplacing dualheaded locomotives
NOTE: savegame revision bump (peter1138 + me in coop)

(svn r2413) - Codechange: Rewrite the displaying of purchase details a bit, make it easyer to add lines later.
- Add: In the purchase details for trains display "(refittable)" after the capacity if the vehicle is refittable.

(svn r2365) - Change: [refitting] Make refitting capacities for trains newgrf compatible. Train vehicles can now carry twice as much mail/goods as other cargo, and four times as much passengers.
- Fix: [refitting] The refit window now shows the correct refit options for the entire consist. Only if at least one of the vehicles in the train can be refitted to a certain cargo, it is shown in the list.
- Fix: [refitting] When refitting to a cargo which is already carried by some vehicles in the consist, the capacities of those vehicles are taken into account when calculating the new capacity of the train in the refit window.

(svn r2256) - Fix: Trains cannot find a depot when they are in a tunnel. (glx)
- Add: GetVehicleTrackdir() helper function.
- Codechange: Moved SortStruct from vehicle_gui.h to ttd.h, so the dependency from vehicle.h on vehicle_gui.h could be removed.
- Codechange: Typedeffed the VehicleTypes struct so it can be used as the type for Vehicle.type instead of "byte".
- Codechange: Removed prototype for VehicleSorter(), which had no implementation anymore and was never called.

(svn r2192) - Add greater control to the 'message options' window. Now you can turn off the telegraphc ticker sound for summarized messages, or turn off news-messages altogether (you get a red blot to notify you though). The [<][>] set the settings in one way, while clicking on the option itself, cycles it. This commit also 'fixes' bugs [1166973], [1121484] and patch [1169930].
- I also changed an order of strings from On, Off to Off, On, so this can be used ingame with the WWT_4 widget type.
- Since the newssettings now take 2 bits per setting (off/summary/on) _news_display_opt is widened to 32 bits and the settings code changed slightly to accomodate for a maximum of 16 message-types.

(svn r1681) -Feature: New realistic acceleration.
This will make things more difficult as narrow curves
and depots impose rather strict speed limits. Feedback welcome
For those who don't like low-speed curves: Switch it off

(svn r1679) Fix: dropdown menus now returns the index of the string that was clicked even if a previous item is hidden
This bug was not triggered by the current code, but it's easier to code new features if you do not have to think about such limitations
like you can't hide an item in the middle of the list ;)

(svn r1629) added a counter to tell how many engines you have of each type to the autoreplace vehicle windows and made them show only the vehicles you actually have in the left list.
this also fixes some window updates issues when autoreplacing

(svn r1525) -Codechange: rewrote the _order_array, now it can be made dynamic.
-Codechange: renamed all 'schedule' stuff to 'order(list)'
-Codechange: moved all order-stuff to order_cmd.c / order.h
-Codechange: vehicles that share orders are now linked to eachother
with next_shared/prev_shared in Vehicle

Developers: please use AssignOrder to assign data to an order. If not,
you _WILL_ make the save-routine to assert!

(svn r1518) -Fix: server issue where some company names were wrong
-Fix: Highscore troubles; accessing members of deleted window

(svn r1407) -Codechange: changed a lot around _stations, _vehicles, _towns and _industries
(in prepare of dynamic arrays):
- DEREF_XXX is changed into GetXXX
- All direct call are directed via GetXXX
- struct Industry has now an index-field
- ENUM'd some stuff
- Replaced home built loops with FOR_ALL_XXX
- Added _stations_size, _vehicles_size, ... which gives the length of the
array (which will be dynamic in the near future)
- Changed lengtof(XXX) to _XXX_size (e.g. _stations_size)
- Removed all endof(XXX) (because mostly it was part of a FOR_ALL_XXX)
- Made the sort-functions of all 4 dynamic
- Made all 4 Initialize functions more of the same
- Some minor tab-fixing and stuff
(tnx to Tron for proof-reading my 100kb patch ;))

Note for all: please do NOT directly call _stations, _vehicles, _towns and
_industries, but use the right wrapper to access them. Thank you.
Ps: please also do not use 'v++', where v is of type Vehicle *.

(svn r1399) -Fix: Fixes for compiling with Watcom C/C++ (ie, OS/2 port). (orudge)
Note: If people could watch out for initialising structs with
*non-constants* in future... it's a bit annoying, I
know, but Open Watcom isn't the only compiler which
doesn't support this (yet) - Borland, for example,
still doesn't like it.

(svn r1393) fix [ 1096026 ]. Autorenew trains should now hopefully work like it did before autoreplace was added
DEREF_ENGINE is now used in autoreplace

(svn r1350) Replace Vehicle GUI:
- Replaced "WP(w,replaceveh_d).line_height" with
"w->resize.step_height" since they needed to be the same anyway
- Cleaned the code a litte for readability (like correct tabbing)
- Added company color to replace vehicle windows to make them look like
the rest of the vehicle windows and made the caption text white (also to
fit the standard)

--This line, and those below, will be ignored--

M vehicle_gui.c
M lang/english.txt
M window.h

(svn r1348) -Feature: resizable windows. Read the comment in window.h to find out
how the system works. All useful windows are already made resizable. Enjoy :)
-Fix: fixed some GUI-glitches and flaws along the way

(svn r1323) Adding autoreplace feature
This feature works much like autorenew, but it will get you a new engine type instead of a new one of the same type. Once
ordered, it will automatically replace the engines while they visits a depot. The GUI for setting this up have been added on the
vehicle overview windows
Note: autorenew is now autoreplace, but to the same engine type
Nice new features, that was added to make this possible
- windows can now have two independant vertical scrollbars
- CMD_SHOW_NO_ERROR have been added as a flag for DoCommandP. It will make it do the action instead of showing the red box with
estimated costs even if shift is pressed
- fixed problem where enginetypes where not initialized when loading a game. It's now done in InitializeGame()

(svn r1016) Make the cargo sorter not consider the number of wagons of a particular cargo type but the sum of their capacity.
Also add the number sorter to sort by vehicle number if the cargo capacity is equal.

(svn r1009) -Feature: per-station vehicle lists
This adds a little button per vehicle class to the station window which opens a list of all vehicles that have this station on their schedule.
As side effect this gets rid of some global variables.

(svn r901) Small step in the process to clean up the DPARAM mess:
- reduce to 2 sizes (*DParam64 for 64bit values, *DParam for the rest)
- use inline functions instead of macros
- add assert()s to check for buffer overruns

(svn r815) Include strings.h only in the files which need it.
This should reduce the compile time after altering english.txt by about 1/3, because "only" 62 instead of 90 .c files must be recompiled.

(svn r813) Push two tables from vehicle_gui.h into vehicle_gui.c - they were in the binary 48 (!) times.
While here change the type for one table from uint16 to StringID.

(svn r244) -Fix: Stations were not sorted for non-player-0 players
-Fix: Correctly resorting vehicle list of player when the list of another player is open.