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An IMaterialDefinition object represents a material definition in the game. A Material Definition is needed if you want to create a new block.

Importing the package

It might be required for you to import the package if you encounter any issues, so better be safe than sorry and add the import.
import mods.contenttweaker.BlockMaterial;

Calling an IMaterialDefinition object

You can get such an object using the Block Material Bracket Handler:
<blockmaterial:wood>

ZenGetters/ZenMethods without parameters

ZenGetter	ZenMethod	Return Type
ZenGetter blocksLight	ZenMethod blocksLight()	Return Type bool
ZenGetter blocksMovement	ZenMethod blocksMovement()	Return Type bool
ZenGetter canBurn	ZenMethod getCanBurn()	Return Type bool
ZenGetter mobilityFlag	ZenMethod getMobilityFlag()	Return Type PushReaction
ZenGetter liquid	ZenMethod isLiquid()	Return Type bool
ZenGetter opaque	ZenMethod isOpaque()	Return Type bool
ZenGetter replaceable	ZenMethod isReplaceable()	Return Type bool
ZenGetter solid	ZenMethod isSolid()	Return Type bool
ZenGetter toolNotRequired	ZenMethod isToolNotRequired()	Return Type bool

Compare two BlockMaterials

You can use the == operator to see if two MaterialDefinitions are equal

if(materialA == materialB)
    print("success!");