NMLTutorial/Item - Revision history

FooBar: /* Graphics block */

2011-08-30T09:28:31Z

Graphics block

← Older revision		Revision as of 09:28, 30 August 2011
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	<pre class="pseudo">		<pre class="pseudo">
	graphics {		graphics {
	callback: <identifier>\|<return_value>;		<callback>: <identifier>\|<return_value>;
	[<callback2>: <identifier2>\|<return_value2>;]		[<callback2>: <identifier2>\|<return_value2>;]
	[...;]		[...;]
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	For graphics alone, the two "callbacks" <code>default</code> and <code>purchase</code> are of most interest. The <code>default</code> links to the graphics definition for the item itself. The <code>purchase</code> links to a graphics definition specifically for the purchase menu of the feature.		For graphics alone, the two "callbacks" <code>default</code> and <code>purchase</code> are of most interest. The <code>default</code> links to the graphics definition for the item itself. The <code>purchase</code> links to a graphics definition specifically for the purchase menu of the feature.

	What ~~callbacks~~ are available for each feature must be [http://newgrf-specs.tt-wiki.net/wiki/NML:Properties_and_variables_and_callbacks looked up] in the NML Documentation for the feature you are defining. Callback and identifier/return_value are separated by a colon and these pairs are each separated by a semicolon.		What <code><callback></code>s are available for each feature must be [http://newgrf-specs.tt-wiki.net/wiki/NML:Properties_and_variables_and_callbacks looked up] in the NML Documentation for the feature you are defining. Callback and identifier/return_value are separated by a colon and these pairs are each separated by a semicolon.

	=== Livery_override block ===		=== Livery_override block ===

FooBar: pre class

2011-08-27T22:18:57Z

pre class

← Older revision		Revision as of 22:18, 27 August 2011
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	The general syntax for the item block is as follows:		The general syntax for the item block is as follows:

	<pre>		<pre class="pseudo">
	item (<feature> [, <identifier> [, <ID>]]) {		item (<feature> [, <identifier> [, <ID>]]) {
	[<property-block>]		[<property-block>]
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	The general syntax of the property block is:		The general syntax of the property block is:

	<pre>		<pre class="pseudo">
	property {		property {
	<property>: <value>;		<property>: <value>;
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	The general syntax of the property block is:		The general syntax of the property block is:

	<pre>		<pre class="pseudo">
	graphics {		graphics {
	callback: <identifier>\|<return_value>;		callback: <identifier>\|<return_value>;

FooBar: /* Item block syntax */ unique identifiers

2011-08-24T13:03:36Z

Item block syntax: unique identifiers

← Older revision		Revision as of 13:03, 24 August 2011
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	In words this means you start with <code>item</code> followed by an opening bracket, then the identifier for the feature you want to define the item for, then an (optional, but recommended) identifier for this item block and finally an (optional, not recommended) numerical ID for the item. Followed by a closing bracket and an opening curly bracket.		In words this means you start with <code>item</code> followed by an opening bracket, then the identifier for the feature you want to define the item for, then an (optional, but recommended) identifier for this item block and finally an (optional, not recommended) numerical ID for the item. Followed by a closing bracket and an opening curly bracket.

	The <code>feature</code> needs to be selected from a [http://newgrf-specs.tt-wiki.net/wiki/NML:Features list of features]. The <code>identifier</code> is a self-chosen name for this feature. It's useful to start the identifier with ''item_'' followed by the name of the vehicle/station/industry/object/etc.. This prevents duplication with future identifier for other blocks for this item.		The <code>feature</code> needs to be selected from a [http://newgrf-specs.tt-wiki.net/wiki/NML:Features list of features]. The <code>identifier</code> is a self-chosen name for this feature. It's useful to start the identifier with ''item_'' followed by the name of the vehicle/station/industry/object/etc.. This prevents duplication with future identifier for other blocks for this item and is somewhat a guarantee that this identifier is unique.

	<code>ID</code> is something you only need if you want to define an item for a specific NFO ID. If you want that, write a number here, otherwise just omit it. New NewGRFs need normally not to have specific NFO IDs defined, as NML will automatically assign the first available ID if you don't override it with this.		<code>ID</code> is something you only need if you want to define an item for a specific NFO ID. If you want that, write a number here, otherwise just omit it. New NewGRFs need normally not to have specific NFO IDs defined, as NML will automatically assign the first available ID if you don't override it with this.

FooBar: item block theory

2011-08-22T18:24:13Z

item block theory

New page

{{NMLTutorial}}

An item block is a block that defines a (new) vehicle, station, industry, object, etc. This is one of those blocks that come with multiple arguments and need a feature defined (remember the [[NMLTutorial/NML Syntax|NML Syntax page]]?).

== Item block syntax ==
The general syntax for the item block is as follows:

<pre>
item (<feature> [, <identifier> [, <ID>]]) {
[<property-block>]
[<graphics-block>]
[<livery_override-block>]
}
</pre>

In words this means you start with <code>item</code> followed by an opening bracket, then the identifier for the feature you want to define the item for, then an (optional, but recommended) identifier for this item block and finally an (optional, not recommended) numerical ID for the item. Followed by a closing bracket and an opening curly bracket.

The <code>feature</code> needs to be selected from a [http://newgrf-specs.tt-wiki.net/wiki/NML:Features list of features]. The <code>identifier</code> is a self-chosen name for this feature. It's useful to start the identifier with ''item_'' followed by the name of the vehicle/station/industry/object/etc.. This prevents duplication with future identifier for other blocks for this item.

<code>ID</code> is something you only need if you want to define an item for a specific NFO ID. If you want that, write a number here, otherwise just omit it. New NewGRFs need normally not to have specific NFO IDs defined, as NML will automatically assign the first available ID if you don't override it with this.

== Item block contents ==
In the item block you define at least one property block, one graphics block and/or one livery_override block. Multiple of these blocks can go into the item block at the same time (even multiple property blocks, although that doesn't make much sense). If you want nothing too fancy, you'll only have one property block and one graphics block in the item block.

=== Property block ===
The property block, as the name suggests, defines the properties for the item you're defining. In case of a vehicle, you can think of such properties as speed, weight, capacity etc. But there are much more properties available, so you need to [http://newgrf-specs.tt-wiki.net/wiki/NML:Properties_and_variables_and_callbacks look them up] in the NML Documentation for the feature you are defining.

The general syntax of the property block is:

<pre>
property {
<property>: <value>;
[<property2>: <value2>;]
[...;]
}
</pre>

So you define multiple properties in one property block. Property and value are separated by a colon and property/value pairs are each separated by a semicolon.

=== Graphics block ===
The graphics block allows to link the item to a graphics definition or to callbacks. You can have the graphics definition also depend on several variables via an intermediate (random_)switch block. More about switch blocks and callbacks later.

The general syntax of the property block is:

<pre>
graphics {
callback: <identifier>|<return_value>;
[<callback2>: <identifier2>|<return_value2>;]
[...;]
}
</pre>

For the purpose of this syntax, the links to graphic definitions are also called "callbacks" and can only be combined with an identifier. Real callbacks can also return values directy from the graphics definition or link to (random_)switch block.

For graphics alone, the two "callbacks" <code>default</code> and <code>purchase</code> are of most interest. The <code>default</code> links to the graphics definition for the item itself. The <code>purchase</code> links to a graphics definition specifically for the purchase menu of the feature.

What callbacks are available for each feature must be [http://newgrf-specs.tt-wiki.net/wiki/NML:Properties_and_variables_and_callbacks looked up] in the NML Documentation for the feature you are defining. Callback and identifier/return_value are separated by a colon and these pairs are each separated by a semicolon.

=== Livery_override block ===
The livery_override block is (only) available for train engines and allows to change the appearance of wagons attached to a train engine. As this is an advanced feature of NewGRFs and this is a tutorial, we'll not be elaborating on livery_override blocks here. Once you understand how to define normal graphics, you can easily figure this out yourself.

This concludes the theory you need to know about item blocks. Let's continue our road vehicle and add an item block for that.

{{NMLTutorialNavbar|Road vehicle|Road vehicle item definition}}