org.lwjgl.opengl

Class ARBQueryBufferObject

java.lang.Object

org.lwjgl.opengl.ARBQueryBufferObject

public final class ARBQueryBufferObject
extends java.lang.Object

Native bindings to the ARB_query_buffer_object extension.

Statistics about the operation of the OpenGL pipeline, such as the number of samples that passed the depth test, the elapsed time between two events or the number of vertices written by transform feedback can be retrieved from the GL through query objects. The result of a query object is acquired by the application through the OpenGL API into a client provided memory location. Should the result returned by the API be required for use in a shader, it must be passed back to the GL via a program uniform or some other mechanism. This requires a round-trip from the GPU to the CPU and back.

This extension introduces a mechanism whereby the result of a query object may be retrieved into a buffer object instead of client memory. This allows the query rsult to be made available to a shader without a round-trip to the CPU for example by subsequently using the buffer object as a uniform buffer, texture buffer or other data store visible to the shader. This functionality may also be used to place the results of many query objects into a single, large buffer and then map or otherwise read back the entire buffer at a later point in time, avoiding a per-query object CPU-GPU synchronization event.

The extension allows acquiring the result of any query object type supported by the GL implementation into a buffer object. The implementation will determine the most efficient method of copying the query result to the buffer.

Requires OpenGL 1.5.

Field Summary

Fields

Modifier and Type	Field and Description
static int	GL_QUERY_BUFFER Accepted by the target parameter of BindBuffer, BufferData, BufferSubData, MapBuffer, UnmapBuffer, MapBufferRange, GetBufferSubData, GetBufferParameteriv, GetBufferParameteri64v, GetBufferPointerv, ClearBufferSubData, and the readtarget and writetarget parameters of CopyBufferSubData.
static int	GL_QUERY_BUFFER_BARRIER_BIT Accepted in the barriers bitfield in MemoryBarrier.
static int	GL_QUERY_BUFFER_BINDING Accepted by the pname parameter of GetBooleanv, GetIntegerv, GetFloatv, and GetDoublev.
static int	GL_QUERY_RESULT_NO_WAIT Accepted by the pname parameter of GetQueryObjectiv, GetQueryObjectuiv, GetQueryObjecti64v and GetQueryObjectui64v.

Method Summary

Methods inherited from class java.lang.Object

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

Field Detail

GL_QUERY_RESULT_NO_WAIT

public static final int GL_QUERY_RESULT_NO_WAIT

Accepted by the pname parameter of GetQueryObjectiv, GetQueryObjectuiv, GetQueryObjecti64v and GetQueryObjectui64v.

See Also:

Constant Field Values

GL_QUERY_BUFFER

public static final int GL_QUERY_BUFFER

Accepted by the target parameter of BindBuffer, BufferData, BufferSubData, MapBuffer, UnmapBuffer, MapBufferRange, GetBufferSubData, GetBufferParameteriv, GetBufferParameteri64v, GetBufferPointerv, ClearBufferSubData, and the readtarget and writetarget parameters of CopyBufferSubData.

See Also:

Constant Field Values

GL_QUERY_BUFFER_BINDING

public static final int GL_QUERY_BUFFER_BINDING

Accepted by the pname parameter of GetBooleanv, GetIntegerv, GetFloatv, and GetDoublev.

See Also:

Constant Field Values

GL_QUERY_BUFFER_BARRIER_BIT

public static final int GL_QUERY_BUFFER_BARRIER_BIT

Accepted in the barriers bitfield in MemoryBarrier.

See Also:

Constant Field Values