Action1

Define a set of real sprites

Action 1

Defining a set of real sprites.

-=Introduction=-

Action 01 is used to define sets of real sprites (as opposed to pseudo-sprites). It can be put anywhere in the .nfo file after Action 8.

-=Format=-

The data looks as follows:

 -+<sprite-number> * <length> 01 <feature> <num-sets> <num-ent>+-

||Element|Size|Description

<sprite-number>|dec|A sequential sprite number

<length>|dec|The total number of bytes used in this action

01|B|Defines action 01

<feature>|B|The feature that following sprites should be used for (s.b.)

<num-sets>|B|The number of sprite sets you have (one sprite set is one vehicle/station/ship etc)

<num-ent>|B*|The number of views the sprite has||

The block of data that always follows after action 01 should consist of num-sets * num-ent RealSprites.

-=Filling in the terms=-

sprite-number

This is just the number you are at.

length

Count the number of bytes in this action.

feature

This sets the type of feature that you wish to change. Set it to:

00 for trains

01 for road vehicles

02 for ships

03 for planes

04 for stations

05 for canals

06 for bridges

07 for houses

09 for industry tiles

0B for cargos

0F for newobjects

10 for rail types (since OpenTTD r18969)

num-sets

The amount of stations, vehicles, ships, etc that the following sprites represent (be warned, one spriteset can be used for more as one vehicle, or truck; you will see this when you reach Action 2 and Action 3)

num-ent

This sets how many different views each entry has.

For vehicles, this corresponds to the different directions it can be in.  If your vehicle is symmetrical you need 4 views, and if it isn't symmetrical then use 8 views.

A station should normally be 12 (hex) because a station is made out of 18 (decimal) sprites, although if you use a different sprite layout for your station this number may vary.

For canals, it depends on the canal feature, see Action 3.

For houses and industry tiles, this should be between 1 and 4 and specifies the number of different construction stages. Sprites after the first four are always ignored. See also action 2 and 3.

For cargos, this should always be 1. The following sprites should be no larger than 10x10 pixels or they won't fit into the station window correctly.

Since TTDPatch 2.0.1 alpha 49, this value is a so-called "extended byte" (see GRFActionsDetailed).

Since 2.0.1 alpha 63, it is possible to have <num-ent>=0. This is useful for defining an action 1/2 combination that only serves as invalid callback result.  If the .grf file defines no graphics otherwise, this way callbacks can return an explicit failure code without needing any actual sprites to be allocated.

-=Example=-

Below is an example of what a real Action 1 pseudo-sprite could look like with the sprite entries under it.

2 * 4 01 00 01 08

3 C:\TTD\SPRITES\mytrain.pcx 66 8 01 18 8 -3 -10

4 C:\TTD\SPRITES\mytrain.pcx 82 8 09 15 20 -14 -6

5 C:\TTD\SPRITES\mytrain.pcx 114 8 01 12 28 -14 -6

6 C:\TTD\SPRITES\mytrain.pcx 162 8 09 16 20 -4 -8

7 C:\TTD\SPRITES\mytrain.pcx 194 8 01 18 8 -3 -10

8 C:\TTD\SPRITES\mytrain.pcx 210 8 09 16 20 -14 -7

9 C:\TTD\SPRITES\mytrain.pcx 242 8 01 12 28 -14 -6

10 C:\TTD\SPRITES\mytrain.pcx 290 8 09 15 20 -4 -7

||Byte|Meaning

2|<sprite-number>

4|<length> of the action in bytes; start counting at 01 (<action>)

01|<action>: sets this pseudo-sprite to function as action 1

00|<feature>: In this case Train

01|<num-sets>: 1 Set of views

08|<num-ent>: 8 views of this train||