bufferobj.c File Reference

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Detailed Description

Functions for the GL_ARB_vertex/pixel_buffer_object extensions.

Author:

Brian Paul, Ian Romanick

#include "glheader.h"
#include "hash.h"
#include "imports.h"
#include "image.h"
#include "context.h"
#include "bufferobj.h"

Defines
#define	DEFAULT_ACCESS   (GL_MAP_READ_BIT | GL_MAP_WRITE_BIT)
Functions
static INLINE struct gl_buffer_object *	get_buffer (GLcontext *ctx, GLenum target)
	Get the buffer object bound to the specified target in a GL context.
static GLenum	simplified_access_mode (GLbitfield access)
	Convert a GLbitfield describing the mapped buffer access flags into one of GL_READ_WRITE, GL_READ_ONLY, or GL_WRITE_ONLY.
static struct gl_buffer_object *	buffer_object_subdata_range_good (GLcontext *ctx, GLenum target, GLintptrARB offset, GLsizeiptrARB size, const char *caller)
	Tests the subdata range parameters and sets the GL error code for glBufferSubDataARB and glGetBufferSubDataARB.
static struct gl_buffer_object *	_mesa_new_buffer_object (GLcontext *ctx, GLuint name, GLenum target)
	Allocate and initialize a new buffer object.
static void	_mesa_delete_buffer_object (GLcontext *ctx, struct gl_buffer_object *bufObj)
	Delete a buffer object.
void	_mesa_reference_buffer_object (GLcontext *ctx, struct gl_buffer_object **ptr, struct gl_buffer_object *bufObj)
	Set ptr to bufObj w/ reference counting.
void	_mesa_initialize_buffer_object (struct gl_buffer_object *obj, GLuint name, GLenum target)
	Initialize a buffer object to default values.
static GLboolean	_mesa_buffer_data (GLcontext *ctx, GLenum target, GLsizeiptrARB size, const GLvoid *data, GLenum usage, struct gl_buffer_object *bufObj)
	Allocate space for and store data in a buffer object.
static void	_mesa_buffer_subdata (GLcontext *ctx, GLenum target, GLintptrARB offset, GLsizeiptrARB size, const GLvoid *data, struct gl_buffer_object *bufObj)
	Replace data in a subrange of buffer object.
static void	_mesa_buffer_get_subdata (GLcontext *ctx, GLenum target, GLintptrARB offset, GLsizeiptrARB size, GLvoid *data, struct gl_buffer_object *bufObj)
	Retrieve data from a subrange of buffer object.
static void *	_mesa_buffer_map (GLcontext *ctx, GLenum target, GLenum access, struct gl_buffer_object *bufObj)
	Default callback for dd_function_tabel::MapBuffer().
static void *	_mesa_buffer_map_range (GLcontext *ctx, GLenum target, GLintptr offset, GLsizeiptr length, GLbitfield access, struct gl_buffer_object *bufObj)
	Default fallback for dd_function_table::MapBufferRange().
static void	_mesa_buffer_flush_mapped_range (GLcontext *ctx, GLenum target, GLintptr offset, GLsizeiptr length, struct gl_buffer_object *obj)
	Default fallback for dd_function_table::FlushMappedBufferRange().
static GLboolean	_mesa_buffer_unmap (GLcontext *ctx, GLenum target, struct gl_buffer_object *bufObj)
	Default callback for dd_function_table::MapBuffer().
static void	_mesa_copy_buffer_subdata (GLcontext *ctx, struct gl_buffer_object *src, struct gl_buffer_object *dst, GLintptr readOffset, GLintptr writeOffset, GLsizeiptr size)
	Default fallback for dd_function_table::CopyBufferSubData().
void	_mesa_init_buffer_objects (GLcontext *ctx)
	Initialize the state associated with buffer objects.
static void	bind_buffer_object (GLcontext *ctx, GLenum target, GLuint buffer)
	Bind the specified target to buffer for the specified context.
void	_mesa_update_default_objects_buffer_objects (GLcontext *ctx)
	Update the default buffer objects in the given context to reference those specified in the shared state and release those referencing the old shared state.
GLboolean	_mesa_validate_pbo_access (GLuint dimensions, const struct gl_pixelstore_attrib *pack, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLenum type, const GLvoid *ptr)
	When we're about to read pixel data out of a PBO (via glDrawPixels, glTexImage, etc) or write data into a PBO (via glReadPixels, glGetTexImage, etc) we call this function to check that we're not going to read out of bounds.
const GLvoid *	_mesa_map_pbo_source (GLcontext *ctx, const struct gl_pixelstore_attrib *unpack, const GLvoid *src)
	For commands that read from a PBO (glDrawPixels, glTexImage, glPolygonStipple, etc), if we're reading from a PBO, map it read-only and return the pointer into the PBO.
const GLvoid *	_mesa_map_validate_pbo_source (GLcontext *ctx, GLuint dimensions, const struct gl_pixelstore_attrib *unpack, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLenum type, const GLvoid *ptr, const char *where)
	Combine PBO-read validation and mapping.
void	_mesa_unmap_pbo_source (GLcontext *ctx, const struct gl_pixelstore_attrib *unpack)
	Counterpart to _mesa_map_pbo_source().
void *	_mesa_map_pbo_dest (GLcontext *ctx, const struct gl_pixelstore_attrib *pack, GLvoid *dest)
	For commands that write to a PBO (glReadPixels, glGetColorTable, etc), if we're writing to a PBO, map it write-only and return the pointer into the PBO.
GLvoid *	_mesa_map_validate_pbo_dest (GLcontext *ctx, GLuint dimensions, const struct gl_pixelstore_attrib *unpack, GLsizei width, GLsizei height, GLsizei depth, GLenum format, GLenum type, GLvoid *ptr, const char *where)
	Combine PBO-write validation and mapping.
void	_mesa_unmap_pbo_dest (GLcontext *ctx, const struct gl_pixelstore_attrib *pack)
	Counterpart to _mesa_map_pbo_dest().
struct gl_buffer_object *	_mesa_lookup_bufferobj (GLcontext *ctx, GLuint buffer)
	Return the gl_buffer_object for the given ID.
static void	unbind (GLcontext *ctx, struct gl_buffer_object **ptr, struct gl_buffer_object *obj)
	If *ptr points to obj, set ptr = the Null/default buffer object.
void	_mesa_init_buffer_object_functions (struct dd_function_table *driver)
	Plug default/fallback buffer object functions into the device driver hooks.
void GLAPIENTRY	_mesa_BindBufferARB (GLenum target, GLuint buffer)
void GLAPIENTRY	_mesa_DeleteBuffersARB (GLsizei n, const GLuint *ids)
	Delete a set of buffer objects.
void GLAPIENTRY	_mesa_GenBuffersARB (GLsizei n, GLuint *buffer)
	Generate a set of unique buffer object IDs and store them in buffer.
GLboolean GLAPIENTRY	_mesa_IsBufferARB (GLuint id)
	Determine if ID is the name of a buffer object.
void GLAPIENTRY	_mesa_BufferDataARB (GLenum target, GLsizeiptrARB size, const GLvoid *data, GLenum usage)
void GLAPIENTRY	_mesa_BufferSubDataARB (GLenum target, GLintptrARB offset, GLsizeiptrARB size, const GLvoid *data)
void GLAPIENTRY	_mesa_GetBufferSubDataARB (GLenum target, GLintptrARB offset, GLsizeiptrARB size, void *data)
void *GLAPIENTRY	_mesa_MapBufferARB (GLenum target, GLenum access)
GLboolean GLAPIENTRY	_mesa_UnmapBufferARB (GLenum target)
void GLAPIENTRY	_mesa_GetBufferParameterivARB (GLenum target, GLenum pname, GLint *params)
void GLAPIENTRY	_mesa_GetBufferPointervARB (GLenum target, GLenum pname, GLvoid **params)
void GLAPIENTRY	_mesa_CopyBufferSubData (GLenum readTarget, GLenum writeTarget, GLintptr readOffset, GLintptr writeOffset, GLsizeiptr size)
void *GLAPIENTRY	_mesa_MapBufferRange (GLenum target, GLintptr offset, GLsizeiptr length, GLbitfield access)
	See GL_ARB_map_buffer_range spec.
void GLAPIENTRY	_mesa_FlushMappedBufferRange (GLenum target, GLintptr offset, GLsizeiptr length)
	See GL_ARB_map_buffer_range spec.

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Define Documentation

#define DEFAULT_ACCESS   (GL_MAP_READ_BIT | GL_MAP_WRITE_BIT)

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Function Documentation

void GLAPIENTRY _mesa_BindBufferARB	(	GLenum	target,
		GLuint	buffer
	)

static GLboolean _mesa_buffer_data	(	GLcontext *	ctx,
		GLenum	target,
		GLsizeiptrARB	size,
		const GLvoid *	data,
		GLenum	usage,
		struct gl_buffer_object *	bufObj
	)			[static]

Allocate space for and store data in a buffer object.

Any data that was previously stored in the buffer object is lost. If data is NULL, memory will be allocated, but no copy will occur.

This is the default callback for dd_function_table::BufferData() Note that all GL error checking will have been done already.

Parameters:

	ctx	GL context.
	target	Buffer object target on which to operate.
	size	Size, in bytes, of the new data store.
	data	Pointer to the data to store in the buffer object. This pointer may be NULL.
	usage	Hints about how the data will be used.
	bufObj	Object to be used.

Returns:

GL_TRUE for success, GL_FALSE for failure

See also:

glBufferDataARB, dd_function_table::BufferData.

static void _mesa_buffer_flush_mapped_range	(	GLcontext *	ctx,
		GLenum	target,
		GLintptr	offset,
		GLsizeiptr	length,
		struct gl_buffer_object *	obj
	)			[static]

Default fallback for dd_function_table::FlushMappedBufferRange().

Called via glFlushMappedBufferRange().

static void _mesa_buffer_get_subdata	(	GLcontext *	ctx,
		GLenum	target,
		GLintptrARB	offset,
		GLsizeiptrARB	size,
		GLvoid *	data,
		struct gl_buffer_object *	bufObj
	)			[static]

Retrieve data from a subrange of buffer object.

If the data range specified by size + offset extends beyond the end of the buffer or if data is NULL, no copy is performed.

This is the default callback for dd_function_table::GetBufferSubData() Note that all GL error checking will have been done already.

Parameters:

	ctx	GL context.
	target	Buffer object target on which to operate.
	offset	Offset of the first byte to be fetched.
	size	Size, in bytes, of the data range.
	data	Destination for data
	bufObj	Object to be used.

See also:

glBufferGetSubDataARB, dd_function_table::GetBufferSubData.

static void* _mesa_buffer_map	(	GLcontext *	ctx,
		GLenum	target,
		GLenum	access,
		struct gl_buffer_object *	bufObj
	)			[static]

Default callback for dd_function_tabel::MapBuffer().

The function parameters will have been already tested for errors.

Parameters:

	ctx	GL context.
	target	Buffer object target on which to operate.
	access	Information about how the buffer will be accessed.
	bufObj	Object to be mapped.

Returns:

A pointer to the object's internal data store that can be accessed by the processor

See also:

glMapBufferARB, dd_function_table::MapBuffer

static void* _mesa_buffer_map_range	(	GLcontext *	ctx,
		GLenum	target,
		GLintptr	offset,
		GLsizeiptr	length,
		GLbitfield	access,
		struct gl_buffer_object *	bufObj
	)			[static]

Default fallback for dd_function_table::MapBufferRange().

Called via glMapBufferRange().

static void _mesa_buffer_subdata	(	GLcontext *	ctx,
		GLenum	target,
		GLintptrARB	offset,
		GLsizeiptrARB	size,
		const GLvoid *	data,
		struct gl_buffer_object *	bufObj
	)			[static]

Replace data in a subrange of buffer object.

If the data range specified by size + offset extends beyond the end of the buffer or if data is NULL, no copy is performed.

This is the default callback for dd_function_table::BufferSubData() Note that all GL error checking will have been done already.

Parameters:

	ctx	GL context.
	target	Buffer object target on which to operate.
	offset	Offset of the first byte to be modified.
	size	Size, in bytes, of the data range.
	data	Pointer to the data to store in the buffer object.
	bufObj	Object to be used.

See also:

glBufferSubDataARB, dd_function_table::BufferSubData.

static GLboolean _mesa_buffer_unmap	(	GLcontext *	ctx,
		GLenum	target,
		struct gl_buffer_object *	bufObj
	)			[static]

Default callback for dd_function_table::MapBuffer().

The input parameters will have been already tested for errors.

See also:

glUnmapBufferARB, dd_function_table::UnmapBuffer

void GLAPIENTRY _mesa_BufferDataARB	(	GLenum	target,
		GLsizeiptrARB	size,
		const GLvoid *	data,
		GLenum	usage
	)

void GLAPIENTRY _mesa_BufferSubDataARB	(	GLenum	target,
		GLintptrARB	offset,
		GLsizeiptrARB	size,
		const GLvoid *	data
	)

static void _mesa_copy_buffer_subdata	(	GLcontext *	ctx,
		struct gl_buffer_object *	src,
		struct gl_buffer_object *	dst,
		GLintptr	readOffset,
		GLintptr	writeOffset,
		GLsizeiptr	size
	)			[static]

Default fallback for dd_function_table::CopyBufferSubData().

Called via glCopyBuffserSubData().

void GLAPIENTRY _mesa_CopyBufferSubData	(	GLenum	readTarget,
		GLenum	writeTarget,
		GLintptr	readOffset,
		GLintptr	writeOffset,
		GLsizeiptr	size
	)

static void _mesa_delete_buffer_object	(	GLcontext *	ctx,
		struct gl_buffer_object *	bufObj
	)			[static]

Delete a buffer object.

Default callback for the dd_function_table::DeleteBuffer() hook.

void GLAPIENTRY _mesa_DeleteBuffersARB	(	GLsizei	n,
		const GLuint *	ids
	)

Delete a set of buffer objects.

Parameters:

	n	Number of buffer objects to delete.
	ids	Array of n buffer object IDs.

void GLAPIENTRY _mesa_FlushMappedBufferRange	(	GLenum	target,
		GLintptr	offset,
		GLsizeiptr	length
	)

See GL_ARB_map_buffer_range spec.

void GLAPIENTRY _mesa_GenBuffersARB	(	GLsizei	n,
		GLuint *	buffer
	)

Generate a set of unique buffer object IDs and store them in buffer.

Parameters:

	n	Number of IDs to generate.
	buffer	Array of n locations to store the IDs.

void GLAPIENTRY _mesa_GetBufferParameterivARB	(	GLenum	target,
		GLenum	pname,
		GLint *	params
	)

void GLAPIENTRY _mesa_GetBufferPointervARB	(	GLenum	target,
		GLenum	pname,
		GLvoid **	params
	)

void GLAPIENTRY _mesa_GetBufferSubDataARB	(	GLenum	target,
		GLintptrARB	offset,
		GLsizeiptrARB	size,
		void *	data
	)

void _mesa_init_buffer_object_functions

(

struct dd_function_table *

driver

)

Plug default/fallback buffer object functions into the device driver hooks.

void _mesa_init_buffer_objects

(

GLcontext *

ctx

)

Initialize the state associated with buffer objects.

void _mesa_initialize_buffer_object	(	struct gl_buffer_object *	obj,
		GLuint	name,
		GLenum	target
	)

Initialize a buffer object to default values.

GLboolean GLAPIENTRY _mesa_IsBufferARB

(

GLuint

id

)

Determine if ID is the name of a buffer object.

Parameters:

id

ID of the potential buffer object.

Returns:

GL_TRUE if id is the name of a buffer object, GL_FALSE otherwise.

struct gl_buffer_object* _mesa_lookup_bufferobj	(	GLcontext *	ctx,
		GLuint	buffer
	)			[read]

Return the gl_buffer_object for the given ID.

Always return NULL for ID 0.

void* _mesa_map_pbo_dest	(	GLcontext *	ctx,
		const struct gl_pixelstore_attrib *	pack,
		GLvoid *	dest
	)

For commands that write to a PBO (glReadPixels, glGetColorTable, etc), if we're writing to a PBO, map it write-only and return the pointer into the PBO.

If we're not writing to a PBO, return dst as-is. If non-null return, must call _mesa_unmap_pbo_dest() when done.

Returns:

NULL if error, else pointer to start of data

const GLvoid* _mesa_map_pbo_source	(	GLcontext *	ctx,
		const struct gl_pixelstore_attrib *	unpack,
		const GLvoid *	src
	)

For commands that read from a PBO (glDrawPixels, glTexImage, glPolygonStipple, etc), if we're reading from a PBO, map it read-only and return the pointer into the PBO.

If we're not reading from a PBO, return src as-is. If non-null return, must call _mesa_unmap_pbo_source() when done.

Returns:

NULL if error, else pointer to start of data

GLvoid* _mesa_map_validate_pbo_dest	(	GLcontext *	ctx,
		GLuint	dimensions,
		const struct gl_pixelstore_attrib *	unpack,
		GLsizei	width,
		GLsizei	height,
		GLsizei	depth,
		GLenum	format,
		GLenum	type,
		GLvoid *	ptr,
		const char *	where
	)

Combine PBO-write validation and mapping.

If any GL errors are detected, they'll be recorded and NULL returned.

See also:

_mesa_validate_pbo_access

_mesa_map_pbo_dest A call to this function should have a matching call to _mesa_unmap_pbo_dest().

const GLvoid* _mesa_map_validate_pbo_source	(	GLcontext *	ctx,
		GLuint	dimensions,
		const struct gl_pixelstore_attrib *	unpack,
		GLsizei	width,
		GLsizei	height,
		GLsizei	depth,
		GLenum	format,
		GLenum	type,
		const GLvoid *	ptr,
		const char *	where
	)

Combine PBO-read validation and mapping.

If any GL errors are detected, they'll be recorded and NULL returned.

See also:

_mesa_validate_pbo_access

_mesa_map_pbo_source A call to this function should have a matching call to _mesa_unmap_pbo_source().

void* GLAPIENTRY _mesa_MapBufferARB	(	GLenum	target,
		GLenum	access
	)

void* GLAPIENTRY _mesa_MapBufferRange	(	GLenum	target,
		GLintptr	offset,
		GLsizeiptr	length,
		GLbitfield	access
	)

See GL_ARB_map_buffer_range spec.

static struct gl_buffer_object* _mesa_new_buffer_object	(	GLcontext *	ctx,
		GLuint	name,
		GLenum	target
	)			[static, read]

Allocate and initialize a new buffer object.

Default callback for the dd_function_table::NewBufferObject() hook.

void _mesa_reference_buffer_object	(	GLcontext *	ctx,
		struct gl_buffer_object **	ptr,
		struct gl_buffer_object *	bufObj
	)

Set ptr to bufObj w/ reference counting.

void _mesa_unmap_pbo_dest	(	GLcontext *	ctx,
		const struct gl_pixelstore_attrib *	pack
	)

Counterpart to _mesa_map_pbo_dest().

void _mesa_unmap_pbo_source	(	GLcontext *	ctx,
		const struct gl_pixelstore_attrib *	unpack
	)

Counterpart to _mesa_map_pbo_source().

GLboolean GLAPIENTRY _mesa_UnmapBufferARB

(

GLenum

target

)

void _mesa_update_default_objects_buffer_objects

(

GLcontext *

ctx

)

Update the default buffer objects in the given context to reference those specified in the shared state and release those referencing the old shared state.

GLboolean _mesa_validate_pbo_access	(	GLuint	dimensions,
		const struct gl_pixelstore_attrib *	pack,
		GLsizei	width,
		GLsizei	height,
		GLsizei	depth,
		GLenum	format,
		GLenum	type,
		const GLvoid *	ptr
	)

When we're about to read pixel data out of a PBO (via glDrawPixels, glTexImage, etc) or write data into a PBO (via glReadPixels, glGetTexImage, etc) we call this function to check that we're not going to read out of bounds.

XXX This would also be a convenient time to check that the PBO isn't currently mapped. Whoever calls this function should check for that. Remember, we can't use a PBO when it's mapped!

If we're not using a PBO, this is a no-op.

Parameters:

	width	width of image to read/write
	height	height of image to read/write
	depth	depth of image to read/write
	format	format of image to read/write
	type	datatype of image to read/write
	ptr	the user-provided pointer/offset

Returns:

GL_TRUE if the PBO access is OK, GL_FALSE if the access would go out of bounds.

static void bind_buffer_object	(	GLcontext *	ctx,
		GLenum	target,
		GLuint	buffer
	)			[static]

Bind the specified target to buffer for the specified context.

static struct gl_buffer_object* buffer_object_subdata_range_good	(	GLcontext *	ctx,
		GLenum	target,
		GLintptrARB	offset,
		GLsizeiptrARB	size,
		const char *	caller
	)			[static, read]

Tests the subdata range parameters and sets the GL error code for glBufferSubDataARB and glGetBufferSubDataARB.

Parameters:

	ctx	GL context.
	target	Buffer object target on which to operate.
	offset	Offset of the first byte of the subdata range.
	size	Size, in bytes, of the subdata range.
	caller	Name of calling function for recording errors.

Returns:

A pointer to the buffer object bound to target in the specified context or NULL if any of the parameter or state conditions for glBufferSubDataARB or glGetBufferSubDataARB are invalid.

See also:

glBufferSubDataARB, glGetBufferSubDataARB

static INLINE struct gl_buffer_object* get_buffer	(	GLcontext *	ctx,
		GLenum	target
	)			[static, read]

Get the buffer object bound to the specified target in a GL context.

Parameters:

	ctx	GL context
	target	Buffer object target to be retrieved. Currently this must be either GL_ARRAY_BUFFER or GL_ELEMENT_ARRAY_BUFFER.

Returns:

A pointer to the buffer object bound to target in the specified context or NULL if target is invalid.

static GLenum simplified_access_mode

(

GLbitfield

access

)

[static]

Convert a GLbitfield describing the mapped buffer access flags into one of GL_READ_WRITE, GL_READ_ONLY, or GL_WRITE_ONLY.

static void unbind	(	GLcontext *	ctx,
		struct gl_buffer_object **	ptr,
		struct gl_buffer_object *	obj
	)			[static]

If *ptr points to obj, set ptr = the Null/default buffer object.

This is a helper for buffer object deletion. The GL spec says that deleting a buffer object causes it to get unbound from all arrays in the current context.

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