javax.media.opengl
Class DefaultGLCapabilitiesChooser

java.lang.Object
  javax.media.opengl.DefaultGLCapabilitiesChooser

All Implemented Interfaces:

GLCapabilitiesChooser

public class DefaultGLCapabilitiesChooser

extends Object

implements GLCapabilitiesChooser

The default implementation of the GLCapabilitiesChooser interface, which provides consistent visual selection behavior across platforms. The precise algorithm is deliberately left loosely specified. Some properties are:

• As long as there is at least one available non-null GLCapabilities which matches the "stereo" option, will return a valid index.
• Attempts to match as closely as possible the given GLCapabilities, but will select one with fewer capabilities (i.e., lower color depth) if necessary.
• Prefers hardware-accelerated visuals to non-hardware-accelerated.
• If there is no exact match, prefers a more-capable visual to a less-capable one.
• If there is more than one exact match, chooses an arbitrary one.
• May select the opposite of a double- or single-buffered visual (based on the user's request) in dire situations.
• Color depth (including alpha) mismatches are weighted higher than depth buffer mismatches, which are in turn weighted higher than accumulation buffer (including alpha) and stencil buffer depth mismatches.
• If a valid windowSystemRecommendedChoice parameter is supplied, chooses that instead of using the cross-platform code.

Constructor Summary

DefaultGLCapabilitiesChooser()

Method Summary

int	chooseCapabilities(GLCapabilities desired, GLCapabilities[] available, int windowSystemRecommendedChoice) Chooses the index (0..available.length - 1) of the GLCapabilities most closely matching the desired one from the list of all supported.

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultGLCapabilitiesChooser

public DefaultGLCapabilitiesChooser()

Method Detail

chooseCapabilities

public int chooseCapabilities(GLCapabilities desired,
                              GLCapabilities[] available,
                              int windowSystemRecommendedChoice)

Description copied from interface: GLCapabilitiesChooser

Chooses the index (0..available.length - 1) of the GLCapabilities most closely matching the desired one from the list of all supported. Some of the entries in the available array may be null; the chooser must ignore these. The windowSystemRecommendedChoice parameter may be provided to the chooser by the underlying window system; if this index is valid, it is recommended, but not necessarily required, that the chooser select that entry.

Note: this method is called automatically by the GLDrawableFactory when an instance of this class is passed in to one of its factory methods. It should generally not be invoked by users directly, unless it is desired to delegate the choice to some other GLCapabilitiesChooser object.

Specified by:

chooseCapabilities in interface GLCapabilitiesChooser