com.hdcookbook.grin.features
Class Group

java.lang.Object
  extended by com.hdcookbook.grin.Feature
      extended by com.hdcookbook.grin.features.Group
All Implemented Interfaces:
Node
Direct Known Subclasses:
SEGroup

public class Group
extends Feature
implements Node

Represents a group of features that are all activated at the same time. It's useful to group features together so that they can be turned on and off as a unit within an assembly.

Author:
Bill Foote (http://jovial.com)

Field Summary
 
Fields inherited from class com.hdcookbook.grin.Feature
name, show
 
Constructor Summary
Group(Show show)
           
 
Method Summary
 void addDisplayAreas(RenderContext context)
          Add all of the areas that are displayed for this feature with the current frame.
 void addSubgraph(java.util.HashSet set)
          This is an implementation method that is not intended to be called direction by applications.
protected  Feature createClone(java.util.HashMap clones)
          This is an implementation method that should not be called direction by applications; applications should call cloneSubgraph().
 void destroy()
          Free any resources held by this feature.
 Feature[] getParts()
          Get the parts that make up this group in the original scene graph.
 int getX()
          Get the upper-left hand corner of this feature as presently displayed.
 int getY()
          Get the upper-left hand corner of this feature as presently displayed Return Integer.MAX_VALUE if this feature has no visible representation.
 void initialize()
          Initialize this feature.
protected  void initializeClone(Feature original, java.util.HashMap clones)
          This is an implementation method that should not be called direction by applications; it is called from cloneSubgraph().
 void markDisplayAreasChanged()
          Mark the display areas of this feature as modified for the next call to addDisplayAreas.
 boolean needsMoreSetup()
          This is where the feaure says whether or not it needs more setup.
 void nextFrame()
          Called from Segment with the Show lock held, to advance us to the state we should be in for the next frame.
 void paintFrame(java.awt.Graphics2D gr)
          Paint the current state of this feature to gr.
 void readInstanceData(GrinDataInputStream in, int length)
          Reads in this node information from the binary file format.
 void resetVisibleParts(Feature[] visibleParts)
          Re-sets the parts that are visible in this group to a new set.
 void resetVisiblePartsNoAssert(Feature[] visibleParts)
          Re-sets the parts that are visible in this group to a new set without performing any of the assertion checks.
protected  void setActivateMode(boolean mode)
          Change the activated mode of this feature.
protected  void setParts(Feature[] parts)
          Set the parts that make up this group.
protected  int setSetupMode(boolean mode)
          Change the setup mode of this feature.
 
Methods inherited from class com.hdcookbook.grin.Feature
activate, cloneCommands, clonedReference, cloneSubgraph, deactivate, destroyClonedSubgraph, getName, isSetup, makeNewClone, resetFeature, sendFeatureSetup, setName, setup, toString, unsetup
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

Group

public Group(Show show)
Method Detail

createClone

protected Feature createClone(java.util.HashMap clones)
This is an implementation method that should not be called direction by applications; applications should call cloneSubgraph(). New subclasses of Feature that wish to support cloning must override this method.

Create a new clone of this feature. This method creates a new instance of this feature, and creates new instances of any sub-features, but it does not initialize the feature. This method is called from Feature.makeNewClone().

See the documentation of cloneSubgraph() for a list of runtime exceptions this method can throw. Subclasses that wish to support cloning must override this method.

Overrides:
createClone in class Feature
Parameters:
clones - A map from original feature to cloned feature. Entries are added by Feature.makeNewClone().
See Also:
Feature.makeNewClone(java.util.HashMap), Feature.cloneSubgraph(java.util.HashMap)

initializeClone

protected void initializeClone(Feature original,
                               java.util.HashMap clones)
This is an implementation method that should not be called direction by applications; it is called from cloneSubgraph(). New subclasses of Feature may override this method.

Initialize this cloned feature from its original. This is called after the entire subgraph has been cloned, so the HashMap containing the set of clones will be complete. See the documentation of cloneSubgraph() for a list of runtime exceptions this method can throw. Subclasses that wish to support cloning must override this method.

If this feature doesn't need initialization it's OK for a feature to not implement it; the default version of this method does nothing. Typically, you only need to implement this for features that have references to other features that aren't sub-features, or that have commands that might have references to other features.

Overrides:
initializeClone in class Feature
See Also:
Feature.cloneSubgraph(java.util.HashMap)

addSubgraph

public void addSubgraph(java.util.HashSet set)
This is an implementation method that is not intended to be called direction by applications. New subclasses of Feature may override this method, and must overrride it if they have children.

Add this node and all of its descendent nodes to the given set. The superclass definition of this method adds the current node. Any node types that have children should override this method to call the superclass version, then recursively invoke this method on each child.

Overrides:
addSubgraph in class Feature

getParts

public Feature[] getParts()
Get the parts that make up this group in the original scene graph.


setParts

protected void setParts(Feature[] parts)
Set the parts that make up this group. This may only be called when the object is initially being populated.


getX

public int getX()
Get the upper-left hand corner of this feature as presently displayed. Return Integer.MAX_VALUE if this feature has no visible representation.

Specified by:
getX in class Feature
Returns:
the x coordinate

getY

public int getY()
Get the upper-left hand corner of this feature as presently displayed Return Integer.MAX_VALUE if this feature has no visible representation.

Specified by:
getY in class Feature
Returns:
the y coordinate

initialize

public void initialize()
Initialize this feature. This is called on show initialization. A show will initialize all of its features after it initializes the segments.

Specified by:
initialize in class Feature

destroy

public void destroy()
Free any resources held by this feature. It is the opposite of setup; each call to setup() shall be balanced by a call to unsetup(), and they shall *not* be nested.

It's possible an active segment may be destroyed. For example, the last segment a show is in when the show is destroyed will probably be active (and it will probably be an empty segment too!).

Specified by:
destroy in class Feature

resetVisibleParts

public void resetVisibleParts(Feature[] visibleParts)
Re-sets the parts that are visible in this group to a new set. This method may be used to make features created with cloneSubgraph() visible. Indeed, with the feeatures built into GRIN, this is the only way to display a cloned feature. Such features don't need to be set up in the way that normal features are (via Feature.setup() which is balanced by Feature.unsetup()), but they do need to be cloned from features that have been set up.

This method may be called by xlet code, but it must only be called within a command body or inside of Director.notifyNextFrame().

If called with a non-null argument, then this group must be in the set up state. If the argument is null and we're not set up, then we must also not be activated.

If this group node is activated, then the new child features of this node will be activated by calling this method, and the old children will be deactivated. This is done synchronously, within this method.

This method relies on resetVisiblePartsNoAssert(Feature[]) after performing appropriate parameter and state checks.

Parameters:
visibleParts - An array of parts. We take ownership of the array. A value of null re-sets this group to its original state.
See Also:
Feature.cloneSubgraph(java.util.HashMap), resetVisiblePartsNoAssert(Feature[])

resetVisiblePartsNoAssert

public void resetVisiblePartsNoAssert(Feature[] visibleParts)
Re-sets the parts that are visible in this group to a new set without performing any of the assertion checks.

Parameters:
visibleParts - An array of parts. We take ownership of the array. A value of null re-sets this group to its original state.
See Also:
resetVisibleParts(Feature[])

setActivateMode

protected void setActivateMode(boolean mode)
Change the activated mode of this feature. The new mode will always be different than the old. Clients of the GRIN framework should never call this method directly. Custom feature extensions must implement this method.

Specified by:
setActivateMode in class Feature

setSetupMode

protected int setSetupMode(boolean mode)
Change the setup mode of this feature. The new mode will always be different than the old. Clients of the GRIN framework should never call this method directly. Custom feature extensions must implement this method.

This method must return a guaranteed lower bound for the number of times it will send a feature setup command as a result of this call. That is, it must send at least as many feature setup commands to the segment as the number returned; sending an accurate number makes the setup process more efficient, since the time it takes to process a command scales with the number of features in a segment. When mode is false, 0 should be returned.

Specified by:
setSetupMode in class Feature

needsMoreSetup

public boolean needsMoreSetup()
This is where the feaure says whether or not it needs more setup. Calls to this are synchronized within the init manager to avoid race conditions. The implementation of this method must not call outside code or call any animation manager methods. For a given setup cycle, this method is called only after setup(). Clients of the GRIN framework should never call this method directly. Custom feature extensions must implement this method.

Specified by:
needsMoreSetup in class Feature
See Also:
SetupClient.needsMoreSetup()

markDisplayAreasChanged

public void markDisplayAreasChanged()
Mark the display areas of this feature as modified for the next call to addDisplayAreas. This can be called by a parent node on its children, e.g. when the parent is deactivated. This is necessary because a parent node might modify the drawing of its children (e.g. by setting an alpha value), and a parent might be taken out of a render tree when its children are not.

See also Issue 121

Specified by:
markDisplayAreasChanged in class Feature
See Also:
Feature.addDisplayAreas(com.hdcookbook.grin.animator.RenderContext)

addDisplayAreas

public void addDisplayAreas(RenderContext context)
Add all of the areas that are displayed for this feature with the current frame. This will be called exactly once per frame displayed on each activated feature.

A feature that displays something needs to maintain a record of it in a DrawRecord. The animation framework uses this to track what needs to be erased and drawn from frame to frame.

Clients of the GRIN framework should not call this method directly. Feature subclasses must implement this method.

Specified by:
addDisplayAreas in class Feature
Parameters:
context - The context for tracking rendering state
See Also:
DrawRecord

paintFrame

public void paintFrame(java.awt.Graphics2D gr)
Paint the current state of this feature to gr. Clients of the GRIN framework should not call this method directly. Feature subclasses must implement this method.

Specified by:
paintFrame in class Feature
Parameters:
gr - The place to paint to.

nextFrame

public void nextFrame()
Called from Segment with the Show lock held, to advance us to the state we should be in for the next frame.

Specified by:
nextFrame in class Feature

readInstanceData

public void readInstanceData(GrinDataInputStream in,
                             int length)
                      throws java.io.IOException
Description copied from interface: Node
Reads in this node information from the binary file format.

An implementation of this method is recommended to call in.readSuperClassData(this) as the first line of the method to read in information that is defined in the base class of this Node type.

This should only be called while initializing this object.

Specified by:
readInstanceData in interface Node
Parameters:
in - InputStream to read data from.
length - the number of bytes that this node's information occupies in the InputStream. The implementation of this method is expected to read exactly this number of bytes from the stream. This can be used for a debugging purpose.
Throws:
java.io.IOException - if error occurs.
See Also:
GrinDataInputStream.readSuperClassData(Feature), GrinDataInputStream.readSuperClassData(RCHandler), GrinDataInputStream.readSuperClassData(Segment), GrinDataInputStream.readSuperClassData(Command)