Package 

Class TransformManager

  • 
public class TransformManager

    TransformManager is used to add transform components to entities.

    A transform component gives an entity a position and orientation in space in the coordinate space of its parent transform. The TransformManager takes care of computing the world-space transform of each component (i.e. its transform relative to the root).

    Creation and destructionA transform component is created using create and destroyed by calling destroy. 
     Engine engine = Engine.create();
 EntityManager entityManager = EntityManager().get();
 int object = entityManager.create();

 TransformManager tcm = engine.getTransformManager();

 // create the transform component
 tcm.create(object);

 // set its transform
 float[] transform = ...; // transform to set
 EntityInstance i = tcm.getInstance(object);
 tcm.setTransform(i, transform));

 // destroy the transform component
 tcm.destroy(object);

    • Method Detail

      • hasComponent

         boolean hasComponent(int entity)

        Returns whether a particular Entity is associated with a component of thisTransformManager

        Parameters:
        entity - an Entity

      • setAccurateTranslationsEnabled

         void setAccurateTranslationsEnabled(boolean enable)

        Enables or disable the accurate translation mode. Disabled by default.When accurate translation mode is active, the translation component of all transforms ismaintained at double precision. This is only useful if the mat4 version of setTransform()is used, as well as getTransformAccurate().

        Parameters:
        enable - true to enable the accurate translation mode, false to disable.

      • create

         int create(int entity)

        Creates a transform component and associates it with the given entity. The component isinitialized with the identity transform.If this component already exists on the given entity, it is firstdestroyed as if destroy was called.

        Parameters:
        entity - an Entity to associate a transform component to.

      • create

         int create(int entity, int parent, @Nullable() @Size(min = 16) Array<float> localTransform)

        Creates a transform component with a parent and associates it with the given entity.If this component already exists on the given entity, it is firstdestroyed as if destroy was called.

        Parameters:
        entity - an Entity to associate a transform component to.
        parent - the EntityInstance of the parent transform
        localTransform - the transform, relative to the parent, to initialize the transformcomponent with.

      • create

         int create(int entity, int parent, @Nullable() @Size(min = 16) Array<double> localTransform)

        Creates a transform component with a parent and associates it with the given entity.If this component already exists on the given entity, it is firstdestroyed as if destroy was called.

        Parameters:
        entity - an Entity to associate a transform component to.
        parent - the EntityInstance of the parent transform
        localTransform - the transform, relative to the parent, to initialize the transformcomponent with.

      • destroy

         void destroy(int entity)

        Destroys this component from the given entity, children are orphaned.

        Parameters:
        entity - an Entity.If this transform had children, these are orphaned, which means their localtransform becomes a world transform.

      • setParent

         void setParent(int i, int newParent)

        Re-parents an entity to a new one.

        Parameters:
        i - the EntityInstance of the transform component to re-parent
        newParent - the EntityInstance of the new parent transform.It is an error to re-parent an entity to a descendant and will causeundefined behaviour.

      • getChildren

        @NonNull() Array<int> getChildren(int i, @Nullable() Array<int> outEntities)

        Gets a list of children for a transform component.

        Parameters:
        i - the EntityInstance of the transform component to get the childrenfrom.
        outEntities - array to receive the result sized to the maximum number of children toretrieve.

      • setTransform

         void setTransform(int i, @NonNull() @Size(min = 16) Array<float> localTransform)

        Sets a local transform of a transform component.

        This operation can be slow if the hierarchy of transform is too deep, and thiswill be particularly bad when updating a lot of transforms. In that case,consider using openLocalTransformTransaction / commitLocalTransformTransaction.

        Parameters:
        i - the EntityInstance of the transform component to set the localtransform to.
        localTransform - the local transform (i.e.

      • setTransform

         void setTransform(int i, @NonNull() @Size(min = 16) Array<double> localTransform)

        Sets a local transform of a transform component.

        This operation can be slow if the hierarchy of transform is too deep, and thiswill be particularly bad when updating a lot of transforms. In that case,consider using openLocalTransformTransaction / commitLocalTransformTransaction.

        Parameters:
        i - the EntityInstance of the transform component to set the localtransform to.
        localTransform - the local transform (i.e.

      • getTransform

        @NonNull()@Size(min = 16) Array<float> getTransform(int i, @Nullable() @Size(min = 16) Array<float> outLocalTransform)

        Returns the local transform of a transform component.

        Parameters:
        i - the EntityInstance of the transform component to query thelocal transform from.
        outLocalTransform - a 16 float array to receive the result.

      • getTransform

        @NonNull()@Size(min = 16) Array<double> getTransform(int i, @Nullable() @Size(min = 16) Array<double> outLocalTransform)

        Returns the local transform of a transform component.

        Parameters:
        i - the EntityInstance of the transform component to query thelocal transform from.
        outLocalTransform - a 16 float array to receive the result.

      • getWorldTransform

        @NonNull()@Size(min = 16) Array<float> getWorldTransform(int i, @Nullable() @Size(min = 16) Array<float> outWorldTransform)

        Returns the world transform of a transform component.

        Parameters:
        i - the EntityInstance of the transform component to query theworld transform from.
        outWorldTransform - a 16 float array to receive the result.

      • getWorldTransform

        @NonNull()@Size(min = 16) Array<double> getWorldTransform(int i, @Nullable() @Size(min = 16) Array<double> outWorldTransform)

        Returns the world transform of a transform component.

        Parameters:
        i - the EntityInstance of the transform component to query theworld transform from.
        outWorldTransform - a 16 float array to receive the result.

      • openLocalTransformTransaction

         void openLocalTransformTransaction()

        Opens a local transform transaction. During a transaction, getWorldTransform canreturn an invalid transform until commitLocalTransformTransaction is called.However, setTransform will perform significantly better and in constant time.

        This is useful when updating many transforms and the transform hierarchy is deep (say morethan 4 or 5 levels).

        If the local transform transaction is already open, this is a no-op.

      • commitLocalTransformTransaction

         void commitLocalTransformTransaction()

        Commits the currently open local transform transaction. When this returns, callsto getWorldTransform will return the proper value.

        Failing to call this method when done updating the local transform will causea lot of rendering problems. The system never closes the transactionautomatically.

        If the local transform transaction is not open, this is a no-op.