org.j3d.aviatrix3d
Class DepthBufferState

java.lang.Object
  org.j3d.aviatrix3d.SceneGraphObject
      org.j3d.aviatrix3d.BufferState
          org.j3d.aviatrix3d.DepthBufferState

All Implemented Interfaces:

java.lang.Comparable, BufferStateRenderable, Renderable

public class DepthBufferState
extends BufferState
implements BufferStateRenderable

Describes attributes used when interacting with the depth buffer.

Including this state class in the global setup automatically enables depth testing and the depth buffer. If an instance of this state is not included in the scene, the default values, and depth testing are enabled automatically. Use this class to override the defaults, or to deliberately disable depth testing.

The default setup for this class is:

• Minimum range: 0
• Maximum range: 1
• Clear depth: 1
• Depth Testin: true
• Depth Write: true
• Depth Function: FUNCTION_ALWAYS

Internationalisation Resource Names

• invalidDepthFunctionMsg: Error message when the given function type does not match one of the available types.
• invalidDepthRangeMsg: Error message when the given depth value is not in the range [0,1].

Version:

$Revision: 2.8 $

Author:

Justin Couch

Field Summary

static int	FUNCTION_ALWAYS Comparison function that always passes.
static int	FUNCTION_EQUAL Comparison function that passes if current depth == range.
static int	FUNCTION_GREATER Comparison function that passes if current depth > range.
static int	FUNCTION_GREATER_OR_EQUAL Comparison function that passes if current depth >= range.
static int	FUNCTION_LESS Comparison function that passes if current depth < range.
static int	FUNCTION_LESS_OR_EQUAL Comparison function that passes if current depth <= range.
static int	FUNCTION_NEVER Comparison function that always fails.
static int	FUNCTION_NOTEQUAL Comparison function that passes if current depth is not equal range.

Fields inherited from class org.j3d.aviatrix3d.BufferState

lastParent, liveCount, parentList

Fields inherited from class org.j3d.aviatrix3d.SceneGraphObject

alive, LISTENER_SET_TIMING_ERR_PROP, updateHandler

Fields inherited from interface org.j3d.aviatrix3d.rendering.BufferStateRenderable

ACCUMULATION_BUFFER, COLOR_BUFFER, DEPTH_BUFFER, GENERAL_BUFFER, STENCIL_BUFFER

Constructor Summary

DepthBufferState()
Constructs a state set with default values.

Method Summary

boolean	checkClearBufferState() Check to see if this buffer should be cleared at the start of this run.
void	clearBufferState(javax.media.opengl.GL gl) Restore all state to the default values.
int	compareTo(DepthBufferState dbs) Compares this object with the specified object for order.
int	compareTo(java.lang.Object o) Compares this object with the specified object for order.
void	enableDepthTest(boolean test) Set the flag for whether the depth testing should be enabled or disabled.
void	enableDepthWrite(boolean write) Set the flag for whether the depth writing should be enabled or disabled.
boolean	equals(DepthBufferState dbs) Compares this object with the specified object to check for equivalence.
boolean	equals(java.lang.Object o) Compare this object for equality to the given object.
int	getBufferBitMask() Get the GL buffer bit flag that this state class represents.
int	getBufferType() Get the type of buffer this state represents.
float	getClearDepth() Get the current depth used when clearing the depth buffer.
int	getDepthFunction() Get the current operation used when the depth tests pass.
float	getMaxRange() Get the current minimum depth range
float	getMinRange() Get the current minimum depth range
boolean	isDepthTestEnabled() Check to see if depth testing is currently enabled.
boolean	isDepthWriteEnabled() Check to see if depth writing is currently enabled.
void	setBufferState(javax.media.opengl.GL gl) Issue ogl commands needed for this buffer to set the initial state, including the initial enabling.
void	setClearBufferState(boolean clear) Set the flag for whether the buffer state should be cleared when this state object is executed.
void	setClearDepth(float depth) Set depth value that the buffer should be cleared to.
void	setDepthFunction(int func) Set the operation that should be performed if the depth tests pass.
void	setMaxRange(float depth) Set maximum depth value that is acceptable to be rendered.
void	setMinRange(float depth) Set minimum depth value that is acceptable to be rendered.
void	updateBufferState(javax.media.opengl.GL gl) Issue ogl commands needed for this component to change the state, assuming that it is already enabled.

Methods inherited from class org.j3d.aviatrix3d.BufferState

addParent, getParents, numParents, removeParent

Methods inherited from class org.j3d.aviatrix3d.SceneGraphObject

checkForCyclicChild, checkForCyclicParent, dataChanged, getAppUpdateWriteTimingMessage, getBoundsWriteTimingMessage, getDataWriteTimingMessage, getUserData, isLive, setLive, setUpdateHandler, setUserData

Methods inherited from class java.lang.Object

clone, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

FUNCTION_NEVER

public static final int FUNCTION_NEVER

Comparison function that always fails.

See Also:

Constant Field Values

FUNCTION_LESS

public static final int FUNCTION_LESS

Comparison function that passes if current depth < range.

See Also:

Constant Field Values

FUNCTION_LESS_OR_EQUAL

public static final int FUNCTION_LESS_OR_EQUAL

Comparison function that passes if current depth <= range.

See Also:

Constant Field Values

FUNCTION_GREATER

public static final int FUNCTION_GREATER

Comparison function that passes if current depth > range.

See Also:

Constant Field Values

FUNCTION_GREATER_OR_EQUAL

public static final int FUNCTION_GREATER_OR_EQUAL

Comparison function that passes if current depth >= range.

See Also:

Constant Field Values

FUNCTION_EQUAL

public static final int FUNCTION_EQUAL

Comparison function that passes if current depth == range.

See Also:

Constant Field Values

FUNCTION_NOTEQUAL

public static final int FUNCTION_NOTEQUAL

Comparison function that passes if current depth is not equal range.

See Also:

Constant Field Values

FUNCTION_ALWAYS

public static final int FUNCTION_ALWAYS

Comparison function that always passes.

See Also:

Constant Field Values

Constructor Detail

DepthBufferState

public DepthBufferState()

Constructs a state set with default values.

Method Detail

getBufferType

public int getBufferType()

Get the type of buffer this state represents.

Specified by:

getBufferType in interface BufferStateRenderable

Returns:

One of the _BUFFER constants

getBufferBitMask

public int getBufferBitMask()

Get the GL buffer bit flag that this state class represents. Used for bulk clearing all the states at once.

Specified by:

getBufferBitMask in interface BufferStateRenderable

Returns:

The bit state constant for Stencil Buffers

checkClearBufferState

public boolean checkClearBufferState()

Check to see if this buffer should be cleared at the start of this run. If it should be, add the bit mask from this state to the global list.

Specified by:

checkClearBufferState in interface BufferStateRenderable

Returns:

true if the state should be cleared

setBufferState

public void setBufferState(javax.media.opengl.GL gl)

Issue ogl commands needed for this buffer to set the initial state, including the initial enabling.

Specified by:

setBufferState in interface BufferStateRenderable

Parameters:

gl - The gl context to draw with

updateBufferState

public void updateBufferState(javax.media.opengl.GL gl)

Issue ogl commands needed for this component to change the state, assuming that it is already enabled.

Specified by:

updateBufferState in interface BufferStateRenderable

Parameters:

gl - The gl context to draw with

clearBufferState

public void clearBufferState(javax.media.opengl.GL gl)

Restore all state to the default values.

Specified by:

clearBufferState in interface BufferStateRenderable

Parameters:

gl - The gl context to draw with

compareTo

public int compareTo(java.lang.Object o)
              throws java.lang.ClassCastException

Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Specified by:

compareTo in interface java.lang.Comparable

Parameters:

o - The objec to be compared

Returns:

-1, 0 or 1 depending on order

Throws:

java.lang.ClassCastException - The specified object's type prevents it from being compared to this Object

equals

public boolean equals(java.lang.Object o)

Compare this object for equality to the given object.

Specified by:

equals in interface Renderable

Overrides:

equals in class java.lang.Object

Parameters:

o - The object to be compared

Returns:

True if these represent the same values

setClearBufferState

public void setClearBufferState(boolean clear)
                         throws InvalidWriteTimingException

Set the flag for whether the buffer state should be cleared when this state object is executed.

Parameters:

clear - True if the buffer should be cleared when this is the first state to be used in the current operation

Throws:

InvalidWriteTimingException - An attempt was made to write outside of the NodeUpdateListener data changed callback method

enableDepthTest

public void enableDepthTest(boolean test)
                     throws InvalidWriteTimingException

Set the flag for whether the depth testing should be enabled or disabled.

Parameters:

test - True if testing should be enabled state to be used in the current operation

Throws:

InvalidWriteTimingException - An attempt was made to write outside of the NodeUpdateListener data changed callback method

isDepthTestEnabled

public boolean isDepthTestEnabled()

Check to see if depth testing is currently enabled.

Returns:

true when testing is enabled

enableDepthWrite

public void enableDepthWrite(boolean write)
                      throws InvalidWriteTimingException

Set the flag for whether the depth writing should be enabled or disabled.

Parameters:

write - True if writing should be enabled state to be used in the current operation

Throws:

InvalidWriteTimingException - An attempt was made to write outside of the NodeUpdateListener data changed callback method

isDepthWriteEnabled

public boolean isDepthWriteEnabled()

Check to see if depth writing is currently enabled.

Returns:

true when writing is enabled

setMinRange

public void setMinRange(float depth)
                 throws java.lang.IllegalArgumentException,
                        InvalidWriteTimingException

Set minimum depth value that is acceptable to be rendered. The values must be between zero and one. It is not required that the minimum range be less than the max range.

Parameters:

depth - A distance between 0 and 1

Throws:

InvalidWriteTimingException - An attempt was made to write outside of the NodeUpdateListener data changed callback method

java.lang.IllegalArgumentException - The value provided was out of range

getMinRange

public float getMinRange()

Get the current minimum depth range

Returns:

A value between 0 and 1

setMaxRange

public void setMaxRange(float depth)
                 throws java.lang.IllegalArgumentException,
                        InvalidWriteTimingException

Set maximum depth value that is acceptable to be rendered. The values must be between zero and one. It is not required that the minimum range be less than the max range.

Parameters:

depth - A distance between 0 and 1

Throws:

InvalidWriteTimingException - An attempt was made to write outside of the NodeUpdateListener data changed callback method

java.lang.IllegalArgumentException - The value provided was out of range

getMaxRange

public float getMaxRange()

Get the current minimum depth range

Returns:

A value between 0 and 1

setClearDepth

public void setClearDepth(float depth)
                   throws java.lang.IllegalArgumentException,
                          InvalidWriteTimingException

Set depth value that the buffer should be cleared to. The default value is 1.

Parameters:

depth - A distance between 0 and 1

Throws:

InvalidWriteTimingException - An attempt was made to write outside of the NodeUpdateListener data changed callback method

java.lang.IllegalArgumentException - The value provided was out of range

getClearDepth

public float getClearDepth()

Get the current depth used when clearing the depth buffer.

Returns:

A value between 0 and 1

setDepthFunction

public void setDepthFunction(int func)
                      throws java.lang.IllegalArgumentException,
                             InvalidWriteTimingException

Set the operation that should be performed if the depth tests pass. This should be one of the FUNCTION_ constants at the top of this class.

Parameters:

func - One of the FUNCTION_ constants

Throws:

InvalidWriteTimingException - An attempt was made to write outside of the NodeUpdateListener data changed callback method

java.lang.IllegalArgumentException - The operation value was not one of the valid types.

getDepthFunction

public int getDepthFunction()

Get the current operation used when the depth tests pass.

Returns:

One of the FUNCTION_ constants

compareTo

public int compareTo(DepthBufferState dbs)

Compares this object with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Parameters:

dbs - The attributes instance to be comdbsred

Returns:

-1, 0 or 1 depending on order

equals

public boolean equals(DepthBufferState dbs)

Compares this object with the specified object to check for equivalence.

Parameters:

dbs - The attributes instance to be compared

Returns:

true if the objects represent identical values