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Context State Commands

Commands to get or modify informations of the context state of the current thread. More...

Functions

void glcCallbackFunc (GLCenum inOpcode, GLCfunc inFunc)
void glcDataPointer (GLvoid *inPointer)
void glcDeleteGLObjects (void)
void glcDisable (GLCenum inAttrib)
void glcEnable (GLCenum inAttrib)
GLCfunc glcGetCallbackFunc (GLCenum inOpcode)
const GLCchar * glcGetListc (GLCenum inAttrib, GLint inIndex)
GLint glcGetListi (GLCenum inAttrib, GLint inIndex)
GLvoid * glcGetPointer (GLCenum inAttrib)
const GLCchar * glcGetc (GLCenum inAttrib)
GLfloat glcGetf (GLCenum inAttrib)
GLfloat * glcGetfv (GLCenum inAttrib, GLfloat *outVec)
GLint glcGeti (GLCenum inAttrib)
GLboolean glcIsEnabled (GLCenum inAttrib)
void glcStringType (GLCenum inStringType)
void glcPushAttribQSO (GLbitfield inMask)
void glcPopAttribQSO (void)

Detailed Description

Commands to get or modify informations of the context state of the current thread.

GLC refers to the current context state whenever it executes a command. Most of its state is directly available to the user : in order to control the result of the GLC commands, the user may want to get or modify the state of the current context. This is precisely the purpose of the context state commands.

Note:: Some GLC commands create, use or delete display lists and/or textures. The IDs of those display lists and textures are stored in the current GLC context but the display lists and the textures themselves are managed by the current GL context. In order not to impact the performance of error-free programs, QuesoGLC does not check if the current GL context is the same as the context where the display lists and the textures are actually stored. If the current GL context has changed meanwhile, the result of commands that refer to the corresponding display lists or textures is undefined.

Function Documentation

void glcCallbackFunc	(	GLCenum	inOpcode,
		GLCfunc	inFunc
	)

This command assigns the value inFunc to the callback function variable identified by inOpCode which must be chosen in the following table.

Callback function variables
Name	Enumerant	Initial value	Type signature
GLC_OP_glcUnmappedCode	0x0020	GLC_NONE	*GLboolean ()(GLint)**

The callback function can access to client data in a thread-safe manner with glcGetPointer().

Parameters:

	inOpcode	Type of the callback function
	inFunc	Callback function

See also:

void glcDataPointer ( GLvoid * inPointer )

This command assigns the value inPointer to the variable GLC_DATA_POINTER.

It is used for an access to client data from the callback function assigned to the variable GLC_OP_glcUnmappedCode

glcDataPointer provides a way to store, in the GLC context, a pointer to any data. A GLC callback function can subsequently use the command glcGetPointer() to obtain access to those data in a thread-safe manner.

Parameters:

inPointer

The pointer to assign to GLC_DATA_POINTER

See also:: glcGetPointer()
glcCallbackFunc()

void glcDeleteGLObjects ( void )

This command causes GLC to issue a sequence of GL commands to delete all of the GL objects it owns.

GLC uses the command glDeleteLists to delete all of the GL objects named in GLC_LIST_OBJECT_LIST and uses the command glDeleteTextures to delete all of the GL objects named in GLC_TEXTURE_OBJECT_LIST. When an execution of glcDeleteGLObjects finishes, both of these lists are empty.

Note:: glcDeleteGLObjects deletes only the objects that the current GLC context owns, not all objects in all contexts.

See also:: glcGetListi()

void glcDisable ( GLCenum inAttrib )

This command assigns the value GL_FALSE to the boolean variable identified by inAttrib.

Boolean variables
Name	Enumerant	Initial value
GLC_AUTO_FONT	0x0010	GL_TRUE
GLC_GL_OBJECTS	0x0011	GL_TRUE
GLC_MIPMAP	0x0012	GL_TRUE
GLC_HINTING_QSO	0x8005	GL_FALSE
GLC_EXTRUDE_QSO	0x8006	GL_FALSE
GLC_KERNING_QSO	0x8007	GL_FALSE

Parameters:

inAttrib

A symbolic constant indicating a GLC capability.

See also:: glcIsEnabled()
glcEnable()

void glcEnable ( GLCenum inAttrib )

This command assigns the value GL_TRUE to the boolean variable identified by inAttrib which must be chosen in the table above.

GLC_AUTO_FONT : if enabled, GLC tries to automatically find a font among the masters to map the character code to be rendered (see also glcRenderChar()).
GLC_GL_OBJECTS : if enabled, GLC stores characters rendering commands in GL display lists and textures (if any) in GL texture objects.
GLC_MIPMAP : if enabled, texture objects used by GLC are mipmapped
GLC_HINTING_QSO : if enabled, GLC uses the auto-hinting procedures that are available for most scalable fonts. It gives better results for characters that are rendered at small sizes. Hinting may however generate visual artifacts such as shaking outlines if the character is animated. This attribute should be disabled in such cases.
GLC_EXTRUDE_QSO : if enabled and GLC_RENDER_STYLE is GLC_TRIANGLE then GLC renders extruded characters with a thickness equal to 1.0. A call to glScale3*(1., 1., thickness ) can be added before the rendering commands in order to obtain the desired thickness.
GLC_KERNING_QSO : if enabled, GLC uses kerning information (when available) when string are rendered or measured.

Parameters:

inAttrib

A symbolic constant indicating a GLC attribute.

See also:: glcDisable()
glcIsEnabled()

GLCfunc glcGetCallbackFunc ( GLCenum inOpcode )

This command returns the value of the callback function variable identified by inOpcode.

Currently, inOpcode can only have the value GLC_OP_glcUnmappedCode. Its initial value and the type signature are defined in the table shown in glcCallbackFunc()'s definition.

Parameters:

inOpcode

The callback function to be retrieved

Returns:: The value of the callback function variable

See also:: glcCallbackFunc()

const GLCchar* glcGetListc	(	GLCenum	inAttrib,
		GLint	inIndex
	)

This command returns the string at offset inIndex from the first element in the string list identified by inAttrib which must be chosen in the table below :.

String lists
Name	Enumerant	Initial value	Element count variable
GLC_CATALOG_LIST	0x0080	<empty list>	GLC_CATALOG_COUNT

The command raises a GLC_PARAMETER_ERROR if inIndex is less than zero or is greater than or equal to the value of the list's element count variable.

Parameters:

	inAttrib	The string list attribute
	inIndex	The index from which to retrieve an element.

Returns:: The string list element

See also:: glcGetListi()

GLint glcGetListi	(	GLCenum	inAttrib,
		GLint	inIndex
	)

This command returns the integer at offset inIndex from the first element in the integer list identified by inAttrib.

You can choose from the following integer lists, listed below with their element count variables :

Integer lists
Name	Enumerant	Initial value	Element count variable
GLC_CURRENT_FONT_LIST	0x0090	<empty list>	GLC_CURRENT_FONT_COUNT
GLC_FONT_LIST	0x0091	<empty list>	GLC_FONT_COUNT
GLC_LIST_OBJECT_LIST	0x0092	<empty list>	GLC_LIST_OBJECT_COUNT
GLC_TEXTURE_OBJECT_LIST	0x0093	<empty list>	GLC_TEXTURE_OBJECT_COUNT

The command raises a GLC_PARAMETER_ERROR if inIndex is less than zero or is greater than or equal to the value of the list's element count variable.

Parameters:

	inAttrib	The integer list attribute
	inIndex	The index from which to retrieve the element.

Returns:: The element from the integer list.

See also:: glcGetListc()

GLvoid* glcGetPointer ( GLCenum inAttrib )

This command returns the value of the pointer variable identified by inAttrib.

Pointer variables
Name	Enumerant	Initial value
GLC_DATA_POINTER	0x00A0	GLC_NONE

Parameters:

inAttrib

The pointer category

Returns:: The pointer

See also:: glcDataPointer()

const GLCchar* glcGetc ( GLCenum inAttrib )

This command returns the value of the string constant identified by inAttrib.

String constants must be chosen in the table below :

String constants
Name	Enumerant
GLC_EXTENSIONS	0x00B0
GLC_RELEASE	0x00B1
GLC_VENDOR	0x00B2

Parameters:

inAttrib

The attribute that identifies the string constant

Returns:: The string constant.

See also:

GLfloat glcGetf ( GLCenum inAttrib )

This command returns the value of the floating point variable identified by inAttrib.

Float point variables
Name	Enumerant	Initial value
GLC_RESOLUTION	0x00C0	0.0

Parameters:

inAttrib

The parameter value to be returned.

Returns:: The current value of the floating point variable.

See also:

GLfloat* glcGetfv	(	GLCenum	inAttrib,
		GLfloat *	outVec
	)

This command stores into outVec the value of the floating point vector identified by inAttrib.

If the command does not raise an error, it returns outVec, otherwise it returns a NULL value.

Floating point vector variables
Name	Enumerant	Initial value
GLC_BITMAP_MATRIX	0x00D0	[ 1. 0. 0. 1.]

The command raises GLC_PARAMETER_ERROR if outVec is NULL.

Parameters:

	inAttrib	The parameter value to be returned
	outVec	Specifies where to store the return value

Returns:: The current value of the floating point vector variable

See also:

GLint glcGeti ( GLCenum inAttrib )

This command returns the value of the integer variable or constant identified by inAttrib.

Integer variables and constants
Name	Enumerant	Initial value
GLC_CATALOG_COUNT	0x00E0	<implementation specific>
GLC_CURRENT_FONT_COUNT	0x00E1	0
GLC_FONT_COUNT	0x00E2	0
GLC_LIST_OBJECT_COUNT	0x00E3	0
GLC_MASTER_COUNT	0x00E4	<implementation specific>
GLC_MEASURED_CHAR_COUNT	0x00E5	0
GLC_RENDER_STYLE	0x00E6	GLC_BITMAP
GLC_REPLACEMENT_CODE	0x00E7	0
GLC_STRING_TYPE	0x00E8	GLC_UCS1
GLC_TEXTURE_OBJECT_COUNT	0x00E9	0
GLC_VERSION_MAJOR	0x00EA	<implementation specific>
GLC_VERSION_MINOR	0x00EB	<implementation specific>
GLC_MATRIX_STACK_DEPTH_QSO	0x8008	0
GLC_MAX_MATRIX_STACK_DEPTH_QSO	0x8009	<implementation specific>
GLC_ATTRIB_STACK_DEPTH_QSO	0x800C	0
GLC_MAX_ATTRIB_STACK_DEPTH_QSO	0x800D	<implementation specific>

Parameters:

inAttrib

Attribute for which an integer variable is requested.

Returns:: The value or values of the integer variable.

See also:

GLboolean glcIsEnabled ( GLCenum inAttrib )

This command returns GL_TRUE if the value of the boolean variable identified by inAttrib is GL_TRUE (quoted from the specs ^_^).

Attributes that can be enabled or disabled are listed on the glcDisable() description.

Parameters:

inAttrib

The attribute to be tested

Returns:: The state of the attribute inAttrib.

See also:: glcEnable()
glcDisable()

void glcStringType ( GLCenum inStringType )

This command assigns the value inStringType to the variable GLC_STRING_TYPE.

The string types are listed in the table below :

String types
Name	Enumerant	Type of characters
GLC_UCS1	0x0110	GLubyte
GLC_UCS2	0x0111	GLushort
GLC_UCS4	0x0112	GLuint
GLC_UTF8_QSO	0x8004	<character dependent>

Every character string used in the GLC API is represented as a zero-terminated array, unless otherwise specified. The value of the variable GLC_STRING_TYPE determines the interpretation of the array. The values GLC_UCS1, GLC_UCS2, GLC_UCS4 and GLC_UTF8_QSO indicate how each element of the string should be interpreted. Currently QuesoGLC supports UCS1, UCS2, UCS4 and UTF-8 formats as defined in the Unicode 4.0.1 and ISO/IEC 10646:2003 standards. The initial value of GLC_STRING_TYPE is GLC_UCS1.

Note:: Currently, the string formats UCS2 and UCS4 are interpreted according to the underlying platform endianess. If the strings are provided in a different endianess than the platform's, the client must translate the strings in the correct endianess.

The value of a character code in a returned string may exceed the range of the character encoding selected by GLC_STRING_TYPE. In this case, the returned character is converted to a character sequence \<hexcode>, where \ is the character REVERSE SOLIDUS (U+5C), < is the character LESS-THAN SIGN (U+3C), > is the character GREATER-THAN SIGN (U+3E), and hexcode is the original character code represented as a sequence of hexadecimal digits. The sequence has no leading zeros, and alphabetic digits are in upper case.

Parameters:

inStringType

Value to assign to GLC_STRING_TYPE

See also:: glcGeti() with argument GLC_STRING_TYPE

void glcPushAttribQSO ( GLbitfield inMask )

This command provides a means to save groups of state variables.

It takes a OR of symbolic constants indicating which groups of state variables to push onto the attribute stack. Each constant refers to a group of state variables.

Group attributes
Group attribute	Name
enable	GLC_ENABLE_BIT_QSO
render	GLC_RENDER_BIT_QSO
string	GLC_STRING_BIT_QSO
	GLC_GL_ATTRIB_BIT_QSO
	GLC_ALL_ATTRIBS_BIT_QSO

The classification of each variable into a group is indicated in the following table of state variables.

State variables
Name	Type	Get command	Group attribute
GLC_AUTO_FONT	GLboolean	glcIsEnabled()	enable
GLC_GL_OBJECTS	GLboolean	glcIsEnabled()	enable
GLC_MIPMAP	GLboolean	glcIsEnabled()	enable
GLC_HINTING_QSO	GLboolean	glcIsEnabled()	enable
GLC_EXTRUDE_QSO	GLboolean	glcIsEnabled()	enable
GLC_KERNING_QSO	GLboolean	glcIsEnabled()	enable
GLC_RENDER_STYLE	GLint	glcGeti()	render
GLC_RESOLUTION	GLfloat	glcGetf()	render
GLC_STRING_TYPE	GLint	glcGeti()	string
GLC_REPLACEMENT_CODE	GLint	glcGeti()	string
GLC_OP_glcUnmappedCode	GLCfunc	glcGetCallbackFunc()	string
GLC_DATA_POINTER	GLvoid*	glcGetPointer()	string

The error GLC_STACK_OVERFLOW_QSO is generated if glcPushAttribQSO() is executed while the attribute stack depth is equal to GLC_MAX_ATTRIB_STACK_DEPTH_QSO. GLC_STACK_OVERFLOW_QSO.

Parameters:

inMask

The list of state variables to be saved

See also:

glcPopAttribQSO()

glcGeti() with argument GLC_ATTRIB_STACK_DEPTH_QSO

glcGeti() with argument GLC_MAX_ATTRIB_STACK_DEPTH_QSO

void glcPopAttribQSO ( void )

This command resets the values of those state variables that were saved with the last corresponding glcPushAttribQSO().

Those not saved remain unchanged. The error GLC_STACK_UNDERFLOW_QSO is generated if glcPopAttrib() is executed while the attribute stack is empty.

See also:

glcPushAttribQSO()

glcGeti() with argument GLC_ATTRIB_STACK_DEPTH_QSO

glcGeti() with argument GLC_MAX_ATTRIB_STACK_DEPTH_QSO

Generated on Sat Jan 20 20:11:49 2007 for QuesoGLC by