View source for NML:Changes 0.3

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== Introduction ==
Between NML 0.2.x and NML 0.3.x (and their corresponding nightlies) the generated NewGRF version by NML changed from v7 to v8. This brings lot of advantages, but requires a few changes to existing NML files. NewGRFs thus will require a minimum OpenTTD version of 1.2.0 (r23166).

== Callbacks ==
NML 0.3 only supports the new style callbacks. Thus all callback_flag properties have been removed as have the callback flag constants *CBF*. For a complete list of affected constants see the [http://dev.openttdcoop.org/projects/nml/repository/revisions/28c88515e5e7/diff/nml/global_constants.py related commit]

== New named constants ==
A few constants have recently been introduced in both NML 0.2 and 0.3 that make the transition easier. Make sure to use them. For callback "articulated_part" use CB_RESULT_NO_MORE_ARTICULATED_PARTS and/or CB_RESULT_REVERSED_VEHICLE instead of hard-coded 0xFF / 0x80.
For callbacks "cargo_subtype_text", "cargo_subtype_display" and "start_stop" use CB_RESULT_NO_TEXT instead of hard-coded 0xFF.

== Industry availability ==
The callback "availability" is no longer available. Use the callback "construction_probability" instead.

== Heights ==
The "snowline_height" variable returns the height in tiles instead of pixels (=tiles*8).

The "nearby_tile_height" variable returns the height in tiles instead of pixels (=tiles*8).