texobj.c File Reference

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Detailed Description

Texture object management.

#include "mfeatures.h"
#include "colortab.h"
#include "context.h"
#include "enums.h"
#include "fbobject.h"
#include "hash.h"
#include "imports.h"
#include "macros.h"
#include "teximage.h"
#include "texstate.h"
#include "texobj.h"
#include "mtypes.h"
#include "shader/prog_instruction.h"

Internal functions
#define	incomplete(t, why)
	Report why a texture object is incomplete.
struct gl_texture_object *	_mesa_lookup_texture (GLcontext *ctx, GLuint id)
	Return the gl_texture_object for a given ID.
struct gl_texture_object *	_mesa_new_texture_object (GLcontext *ctx, GLuint name, GLenum target)
	Allocate and initialize a new texture object.
void	_mesa_initialize_texture_object (struct gl_texture_object *obj, GLuint name, GLenum target)
	Initialize a new texture object to default values.
static void	finish_texture_init (GLcontext *ctx, GLenum target, struct gl_texture_object *obj)
	Some texture initialization can't be finished until we know which target it's getting bound to (GL_TEXTURE_1D/2D/etc).
void	_mesa_delete_texture_object (GLcontext *ctx, struct gl_texture_object *texObj)
	Deallocate a texture object struct.
void	_mesa_copy_texture_object (struct gl_texture_object *dest, const struct gl_texture_object *src)
	Copy texture object state from one texture object to another.
void	_mesa_clear_texture_object (GLcontext *ctx, struct gl_texture_object *texObj)
	Clear all texture images of the given texture object.
static GLboolean	valid_texture_object (const struct gl_texture_object *tex)
	Check if the given texture object is valid by examining its Target field.
void	_mesa_reference_texobj (struct gl_texture_object **ptr, struct gl_texture_object *tex)
	Reference (or unreference) a texture object.
void	_mesa_test_texobj_completeness (const GLcontext *ctx, struct gl_texture_object *t)
	Examine a texture object to determine if it is complete.
void	_mesa_dirty_texobj (GLcontext *ctx, struct gl_texture_object *texObj, GLboolean invalidate_state)
	Mark a texture object dirty.
struct gl_texture_object *	_mesa_get_fallback_texture (GLcontext *ctx)
	Return pointer to a default/fallback texture.
Functions
API functions
void GLAPIENTRY	_mesa_GenTextures (GLsizei n, GLuint *textures)
	Generate texture names.
static void	unbind_texobj_from_fbo (GLcontext *ctx, struct gl_texture_object *texObj)
	Check if the given texture object is bound to the current draw or read framebuffer.
static void	unbind_texobj_from_texunits (GLcontext *ctx, struct gl_texture_object *texObj)
	Check if the given texture object is bound to any texture image units and unbind it if so (revert to default textures).
void GLAPIENTRY	_mesa_DeleteTextures (GLsizei n, const GLuint *textures)
	Delete named textures.
static GLint	target_enum_to_index (GLenum target)
	Convert a GL texture target enum such as GL_TEXTURE_2D or GL_TEXTURE_3D into the corresponding Mesa texture target index.
void GLAPIENTRY	_mesa_BindTexture (GLenum target, GLuint texName)
	Bind a named texture to a texturing target.
void GLAPIENTRY	_mesa_PrioritizeTextures (GLsizei n, const GLuint *texName, const GLclampf *priorities)
	Set texture priorities.
GLboolean GLAPIENTRY	_mesa_AreTexturesResident (GLsizei n, const GLuint *texName, GLboolean *residences)
	See if textures are loaded in texture memory.
GLboolean GLAPIENTRY	_mesa_IsTexture (GLuint texture)
	See if a name corresponds to a texture.
void	_mesa_lock_context_textures (GLcontext *ctx)
	Simplest implementation of texture locking: grab the shared tex mutex.
void	_mesa_unlock_context_textures (GLcontext *ctx)

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Define Documentation

#define incomplete	(	t,
		why		)

Report why a texture object is incomplete.

Parameters:

	t	texture object.
	why	string describing why it's incomplete.

Note:

For debug purposes only.

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Function Documentation

GLboolean GLAPIENTRY _mesa_AreTexturesResident	(	GLsizei	n,
		const GLuint *	texName,
		GLboolean *	residences
	)

See if textures are loaded in texture memory.

Parameters:

	n	number of textures to query.
	texName	array with the texture names.
	residences	array which will hold the residence status.

Returns:

GL_TRUE if all textures are resident and residences is left unchanged,

See also:

glAreTexturesResident().

Looks up each texture in the hash and calls dd_function_table::IsTextureResident.

void GLAPIENTRY _mesa_BindTexture	(	GLenum	target,
		GLuint	texName
	)

Bind a named texture to a texturing target.

Parameters:

	target	texture target.
	texName	texture name.

See also:

glBindTexture().

Determines the old texture object bound and returns immediately if rebinding the same texture. Get the current texture which is either a default texture if name is null, a named texture from the hash, or a new texture if the given texture name is new. Increments its reference count, binds it, and calls dd_function_table::BindTexture. Decrements the old texture reference count and deletes it if it reaches zero.

void _mesa_clear_texture_object	(	GLcontext *	ctx,
		struct gl_texture_object *	texObj
	)

Clear all texture images of the given texture object.

Parameters:

	ctx	GL context.
	t	texture object.

See also:

_mesa_clear_texture_image().

void _mesa_copy_texture_object	(	struct gl_texture_object *	dest,
		const struct gl_texture_object *	src
	)

Copy texture object state from one texture object to another.

Use for glPush/PopAttrib.

Parameters:

	dest	destination texture object.
	src	source texture object.

void _mesa_delete_texture_object	(	GLcontext *	ctx,
		struct gl_texture_object *	texObj
	)

Deallocate a texture object struct.

It should have already been removed from the texture object pool. Called via ctx->Driver.DeleteTexture() if not overriden by a driver.

Parameters:

	shared	the shared GL state to which the object belongs.
	texObj	the texture object to delete.

void GLAPIENTRY _mesa_DeleteTextures	(	GLsizei	n,
		const GLuint *	textures
	)

Delete named textures.

Parameters:

	n	number of textures to be deleted.
	textures	array of texture IDs to be deleted.

See also:

glDeleteTextures().

If we're about to delete a texture that's currently bound to any texture unit, unbind the texture first. Decrement the reference count on the texture object and delete it if it's zero. Recall that texture objects can be shared among several rendering contexts.

void _mesa_dirty_texobj	(	GLcontext *	ctx,
		struct gl_texture_object *	texObj,
		GLboolean	invalidate_state
	)

Mark a texture object dirty.

It forces the object to be incomplete and optionally forces the context to re-validate its state.

Parameters:

	ctx	GL context.
	texObj	texture object.
	invalidate_state	also invalidate context state.

void GLAPIENTRY _mesa_GenTextures	(	GLsizei	n,
		GLuint *	textures
	)

Generate texture names.

Parameters:

	n	number of texture names to be generated.
	textures	an array in which will hold the generated texture names.

See also:

glGenTextures().

Calls _mesa_HashFindFreeKeyBlock() to find a block of free texture IDs which are stored in textures. Corresponding empty texture objects are also generated.

struct gl_texture_object* _mesa_get_fallback_texture

(

GLcontext *

ctx

)

[read]

Return pointer to a default/fallback texture.

The texture is a 2D 8x8 RGBA texture with all texels = (0,0,0,1). That's the value a sampler should get when sampling from an incomplete texture.

void _mesa_initialize_texture_object	(	struct gl_texture_object *	obj,
		GLuint	name,
		GLenum	target
	)

Initialize a new texture object to default values.

Parameters:

	obj	the texture object
	name	the texture name
	target	the texture target

GLboolean GLAPIENTRY _mesa_IsTexture

(

GLuint

texture

)

See if a name corresponds to a texture.

Parameters:

texture

texture name.

Returns:

GL_TRUE if texture name corresponds to a texture, or GL_FALSE otherwise.

See also:

glIsTexture().

Calls _mesa_HashLookup().

void _mesa_lock_context_textures

(

GLcontext *

ctx

)

Simplest implementation of texture locking: grab the shared tex mutex.

Examine the shared context state timestamp and if there has been a change, set the appropriate bits in ctx->NewState.

This is used to deal with synchronizing things when a texture object is used/modified by different contexts (or threads) which are sharing the texture.

See also _mesa_lock/unlock_texture() in teximage.h

struct gl_texture_object* _mesa_lookup_texture	(	GLcontext *	ctx,
		GLuint	id
	)			[read]

Return the gl_texture_object for a given ID.

struct gl_texture_object* _mesa_new_texture_object	(	GLcontext *	ctx,
		GLuint	name,
		GLenum	target
	)			[read]

Allocate and initialize a new texture object.

But don't put it into the texture object hash table.

Called via ctx->Driver.NewTextureObject, unless overridden by a device driver.

Parameters:

	shared	the shared GL state structure to contain the texture object
	name	integer name for the texture object
	target	either GL_TEXTURE_1D, GL_TEXTURE_2D, GL_TEXTURE_3D, GL_TEXTURE_CUBE_MAP_ARB or GL_TEXTURE_RECTANGLE_NV. zero is ok for the sake of GenTextures()

Returns:

pointer to new texture object.

void GLAPIENTRY _mesa_PrioritizeTextures	(	GLsizei	n,
		const GLuint *	texName,
		const GLclampf *	priorities
	)

Set texture priorities.

Parameters:

	n	number of textures.
	texName	texture names.
	priorities	corresponding texture priorities.

See also:

glPrioritizeTextures().

Looks up each texture in the hash, clamps the corresponding priority between 0.0 and 1.0, and calls dd_function_table::PrioritizeTexture.

void _mesa_reference_texobj	(	struct gl_texture_object **	ptr,
		struct gl_texture_object *	tex
	)

Reference (or unreference) a texture object.

If '*ptr', decrement *ptr's refcount (and delete if it becomes zero). If 'tex' is non-null, increment its refcount.

void _mesa_test_texobj_completeness	(	const GLcontext *	ctx,
		struct gl_texture_object *	t
	)

Examine a texture object to determine if it is complete.

The gl_texture_object::Complete flag will be set to GL_TRUE or GL_FALSE accordingly.

Parameters:

	ctx	GL context.
	t	texture object.

According to the texture target, verifies that each of the mipmaps is present and has the expected size.

void _mesa_unlock_context_textures

(

GLcontext *

ctx

)

static void finish_texture_init	(	GLcontext *	ctx,
		GLenum	target,
		struct gl_texture_object *	obj
	)			[static]

Some texture initialization can't be finished until we know which target it's getting bound to (GL_TEXTURE_1D/2D/etc).

static GLint target_enum_to_index

(

GLenum

target

)

[static]

Convert a GL texture target enum such as GL_TEXTURE_2D or GL_TEXTURE_3D into the corresponding Mesa texture target index.

Return -1 if target is invalid.

static void unbind_texobj_from_fbo	(	GLcontext *	ctx,
		struct gl_texture_object *	texObj
	)			[static]

Check if the given texture object is bound to the current draw or read framebuffer.

If so, Unbind it.

static void unbind_texobj_from_texunits	(	GLcontext *	ctx,
		struct gl_texture_object *	texObj
	)			[static]

Check if the given texture object is bound to any texture image units and unbind it if so (revert to default textures).

static GLboolean valid_texture_object

(

const struct gl_texture_object *

tex

)

[static]

Check if the given texture object is valid by examining its Target field.

For debugging only.

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