ReadingPatchVariables
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Introduction
Since TTDPatch 2.0.1 alpha 48, it has been possible to use action D to read various special Patch variables. These are usually switch values, but there are also a few other useful values.
Syntax
<Sprite-number> * <Length> 0D <target> <operation> <variable> FE FF FF 00 00
| Element | Size | Description |
|---|---|---|
| 0D | B | Defines action 0D |
| <target> | B | Target parameter |
| <operation> | B | As for ActionD, but only assignment is valid. |
| <variable> | B | Patch variable number to read. See below. |
| FE | B | Defines a special variable access |
| FF FF 00 00 | D | Indicates that a patch variable is being read |
variable
The following patch variables are defined:
| variable | Switch | Value |
|---|---|---|
| 00 | miscmods/-Yo | Bit switch |
| 01 | experimentalfeatures/-XF | Bit switch |
| 02 | morevehicles/-x | Vehicle array multiplier |
| 03 | mountains&curves;/-mc | Two bytes with four sets of two bits |
| 04 | planecrashcontrol/-Xc | Bit switch |
| 05 | autorenew/-Xa | Signed value |
| 06 | multihead/-M | Speed increase, in percent |
| 07 | disasters/-XD | Bit switch |
| 08 | unifiedmaglev/-XM | Unified maglev mode |
| 09 | bridgespeedlimits/-XX | Speed fraction, in percent |
| 0A | --- | TTD Language, see the "new scheme" for action 4 |
| 0B | startyear/-XY | Year-1920 |
| 0C | morebuildoptions/-YB | Bit switch |
| 0D | moresteam/-YM | value=LF (two hex digits), L=length, F=frequency |
| 0E | freighttrains/-Yf | weight factor |
| 0F | wagonspeedlimits/-YL | Speed increase for empty wagons |
| 10 | planespeed/-YP | speed factor |
| 11 | dual company colors | 2CC colormap base sprite (since r1404) |
| 12 | miscmods2/-Zm | Bit switch (since r1738) |
| 13 | map size information | Format = -MABXYSS (since r11961 and r1817) |
| M : the type of map | ||
| bit 0 set : squared map. Clear : rectangular map | ||
| bit 1 set : Y is the bigger edge(bit 0 is clear).Clear : X is the bigger edge. | ||
| A : minimum edge(log2) of the map | ||
| B : maximum edge(log2) of the map | ||
| XY : edges(log2) of each side of the map. | ||
| SS : combination of both X and Y, thus giving the size(log2) of the map | ||
| All map sizes will be substracted by 6, as to keep the size 64 the smallest one, thus zero based |
If experimentalfeatures, miscmods, or miscmods2 are off, the corresponding value will be zero. For all other switches, the value is unspecified if the switch is off, so action 7 variable 85 should be checked first.
