Package org.lwjgl.opengl

Class ARBMapBufferRange

java.lang.Object

org.lwjgl.opengl.ARBMapBufferRange

public class ARBMapBufferRange
extends java.lang.Object

Native bindings to the ARB_map_buffer_range extension.

ARB_map_buffer_range expands the buffer object API to allow greater performance when a client application only needs to write to a sub-range of a buffer object. To that end, this extension introduces two new buffer object features: non-serialized buffer modification and explicit sub-range flushing for mapped buffer objects.

OpenGL requires that commands occur in a FIFO manner meaning that any changes to buffer objects either block until the data has been processed by the OpenGL pipeline or else create extra copies to avoid such a block. By providing a method to asynchronously modify buffer object data, an application is then able to manage the synchronization points themselves and modify ranges of data contained by a buffer object even though OpenGL might still be using other parts of it.

This extension also provides a method for explicitly flushing ranges of a mapped buffer object so OpenGL does not have to assume that the entire range may have been modified. Further, it allows the application to more precisely specify its intent with respect to reading, writing, and whether the previous contents of a mapped range of interest need be preserved prior to modification.

Requires OpenGL 2.1. Promoted to core in OpenGL 3.0.

Field Summary

Fields

Modifier and Type	Field and Description
static int	GL_MAP_FLUSH_EXPLICIT_BIT GL_MAP_INVALIDATE_BUFFER_BIT GL_MAP_INVALIDATE_RANGE_BIT GL_MAP_READ_BIT GL_MAP_UNSYNCHRONIZED_BIT GL_MAP_WRITE_BIT Accepted by the access parameter of MapBufferRange.

Method Summary

Modifier and Type	Method and Description
static void	glFlushMappedBufferRange(int target, long offset, long length) Indicates modifications to a range of a mapped buffer.
static java.nio.ByteBuffer	glMapBufferRange(int target, long offset, long length, int access) Maps a section of a buffer object's data store.
static java.nio.ByteBuffer	glMapBufferRange(int target, long offset, long length, int access, java.nio.ByteBuffer old_buffer) Maps a section of a buffer object's data store.

Methods inherited from class java.lang.Object

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

Field Detail

GL_MAP_READ_BIT, GL_MAP_WRITE_BIT, GL_MAP_INVALIDATE_RANGE_BIT, GL_MAP_INVALIDATE_BUFFER_BIT, GL_MAP_FLUSH_EXPLICIT_BIT, GL_MAP_UNSYNCHRONIZED_BIT

Accepted by the access parameter of MapBufferRange.

Method Detail

glMapBufferRange

public static java.nio.ByteBuffer glMapBufferRange(int target,
                                                   long offset,
                                                   long length,
                                                   int access)

public static java.nio.ByteBuffer glMapBufferRange(int target,
                                                   long offset,
                                                   long length,
                                                   int access,
                                                   java.nio.ByteBuffer old_buffer)

Maps a section of a buffer object's data store.

LWJGL note: This method comes in 2 flavors:

1. ARBMapBufferRange.glMapBufferRange(int, long, long, int) - Always returns a new ByteBuffer instance.
2. ARBMapBufferRange.glMapBufferRange(int, long, long, int, ByteBuffer) - The old_buffer parameter is reused if not null.

Parameters:

target - a binding to which the target buffer is bound. One of:

ARRAY_BUFFER	ELEMENT_ARRAY_BUFFER	PIXEL_PACK_BUFFER	PIXEL_UNPACK_BUFFER
TRANSFORM_FEEDBACK_BUFFER	UNIFORM_BUFFER	TEXTURE_BUFFER	COPY_READ_BUFFER
COPY_WRITE_BUFFER	DRAW_INDIRECT_BUFFER	ATOMIC_COUNTER_BUFFER	DISPATCH_INDIRECT_BUFFER
SHADER_STORAGE_BUFFER	PARAMETER_BUFFER_ARB

offset - the starting offset within the buffer of the range to be mapped

length - the length of the range to be mapped

access - a combination of access flags indicating the desired access to the range. One or more of:

MAP_READ_BIT	MAP_WRITE_BIT	MAP_INVALIDATE_RANGE_BIT	MAP_INVALIDATE_BUFFER_BIT
MAP_FLUSH_EXPLICIT_BIT	MAP_UNSYNCHRONIZED_BIT

glFlushMappedBufferRange

public static void glFlushMappedBufferRange(int target,
                                            long offset,
                                            long length)

Indicates modifications to a range of a mapped buffer.

Parameters:

target - the target of the flush operation. One of:

ARRAY_BUFFER	ELEMENT_ARRAY_BUFFER	PIXEL_PACK_BUFFER	PIXEL_UNPACK_BUFFER
TRANSFORM_FEEDBACK_BUFFER	UNIFORM_BUFFER	TEXTURE_BUFFER	COPY_READ_BUFFER
COPY_WRITE_BUFFER	DRAW_INDIRECT_BUFFER	ATOMIC_COUNTER_BUFFER	DISPATCH_INDIRECT_BUFFER
SHADER_STORAGE_BUFFER	PARAMETER_BUFFER_ARB

offset - the start of the buffer subrange, in basic machine units

length - the length of the buffer subrange, in basic machine units