andythenorth · May 7, 2022 15:01
diff --git a/Standardised Railtype Scheme - Innsbruck 2022 Convention for partial compliance b/Standardised Railtype Scheme - Innsbruck 2022 Convention for partial compliance
 Standardised Railtype Scheme - Innsbruck 2022 Convention for partial compliance

 1. The Standardised Railtype Scheme is a useful tool for providing reliable compatibility between train grfs and railtype grfs.

 2. The Axle Load class in the scheme presents a number of issues for compliance.
 2.1. Over 10 years since the scheme was standardised, few train grfs implement the axle load scheme as required (using 5 groups).  Known examples with mostly complete implementations are Dutch Train Set, French Narrow Gauge Trains, and Finnish Trains.
 2.2. Elements of the axle load scheme have proven hard to interpret.  For example, is it compliant to use fewer than 5 groups for trains?
 2.3. Meanwhile multiple train grfs use class 'A' for the axle load for all trains, except where relying on default railtypes such as RAIL and ELRL.

 3. The Innsbruck 2022 Convention uses class 'A' for axle load for all trains in a train grf, except where relying on default railtypes such as RAIL and ELRL.

 This is not fully compliant with the Standardised Railtype Scheme and does not claim to be.

 However train grfs using the Innsbruck 2022 Convention are broadly compatible with railtype grfs using the Standardised Railtype Scheme, but may not use the full range of features provided by railtype grfs with respect to axle load classes

 3.1. The Innsbruck 2022 Convention is not appropriate for train grf authors who wish to provide more than one axle load class.

 3.2. The Innsbruck 2022 Convention treats the meaning of 'A' as 'undefined', 'ignored' or 'compatible with most restricted railtype' for axle load.  

 'A' cannot be safely interpreted as 'universal' because from the perspective of a railtype grf 'A' is 'most restricted railtype', which may be opposite to 'universal railtype', depending how many axle load classes are in use by the railtype grf.

 3.3. When the Innsbruck 2022 Convention is used, this does not prevent a train grf being extended in some future release to achieve full compliance with Standardised Railtype Scheme. That choice remains with train grf authors.

 3.4. If 2012 could be revisited, providing an optional '_' axle load class in the Standardised Railtype Scheme for 'undefined' would have been preferable, but as of 2022, 'A' is already widely used for this purpose.
	Standardised Railtype Scheme - Innsbruck 2022 Convention for partial compliance

	1. The Standardised Railtype Scheme is a useful tool for providing reliable compatibility between train grfs and railtype grfs.

	2. The Axle Load class in the scheme presents a number of issues for compliance.
	2.1. Over 10 years since the scheme was standardised, few train grfs implement the axle load scheme as required (using 5 groups). Known examples with mostly complete implementations are Dutch Train Set, French Narrow Gauge Trains, and Finnish Trains.
	2.2. Elements of the axle load scheme have proven hard to interpret. For example, is it compliant to use fewer than 5 groups for trains?
	2.3. Meanwhile multiple train grfs use class 'A' for the axle load for all trains, except where relying on default railtypes such as RAIL and ELRL.

	3. The Innsbruck 2022 Convention uses class 'A' for axle load for all trains in a train grf, except where relying on default railtypes such as RAIL and ELRL.

	This is not fully compliant with the Standardised Railtype Scheme and does not claim to be.

	However train grfs using the Innsbruck 2022 Convention are broadly compatible with railtype grfs using the Standardised Railtype Scheme, but may not use the full range of features provided by railtype grfs with respect to axle load classes

	3.1. The Innsbruck 2022 Convention is not appropriate for train grf authors who wish to provide more than one axle load class.

	3.2. The Innsbruck 2022 Convention treats the meaning of 'A' as 'undefined', 'ignored' or 'compatible with most restricted railtype' for axle load.

	'A' cannot be safely interpreted as 'universal' because from the perspective of a railtype grf 'A' is 'most restricted railtype', which may be opposite to 'universal railtype', depending how many axle load classes are in use by the railtype grf.

	3.3. When the Innsbruck 2022 Convention is used, this does not prevent a train grf being extended in some future release to achieve full compliance with Standardised Railtype Scheme. That choice remains with train grf authors.

	3.4. If 2012 could be revisited, providing an optional '_' axle load class in the Standardised Railtype Scheme for 'undefined' would have been preferable, but as of 2022, 'A' is already widely used for this purpose.