ReadingOtherGRFParameters

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Introduction

Since TTDPatch 2.0.1 alpha 16, it has been possible to use action D to read the parameters of other GRF files. With this, you can try to use the settings for another related GRF before falling back to a hard coded default.

Format

 <Sprite-number> * <Length> 0D <target> 00 <param> FE <GRFID>
Element Size Description
0D B Defines action 0D
<target> B Target parameter
<param> B Parameter number of the other GRF file that you want to read
FE B Defines a special variable access
<GRFID> D The GRFID whose parameter you want to read

This will store parameter <param> of the GRF file with GRFID <GRFID> into the <target>

With parameter FE you can read the action 14 NewGRF version of another NewGRF in OpenTTD. It returns 0 if no NewGRF version has been set by an action 14.

If the GRFID cannot be found, or if the parameter is not defined, a value of 0 is used instead (no matter whether bit 7 of the operation is set or not).