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Pango Reference Manual | |
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PangoXftFont;
PangoXftFontMap;
#define PANGO_RENDER_TYPE_XFT
PangoContext* pango_xft_get_context (Display *display,
int screen);
PangoFontMap* pango_xft_get_font_map (Display *display,
int screen);
void pango_xft_set_default_substitute
(Display *display,
int screen,
PangoXftSubstituteFunc func,
gpointer data,
GDestroyNotify notify);
void (*PangoXftSubstituteFunc) (FcPattern *pattern,
gpointer data);
void pango_xft_substitute_changed (Display *display,
int screen);
void pango_xft_shutdown_display (Display *display,
int screen);
XftFont* pango_xft_font_get_font (PangoFont *font);
Display* pango_xft_font_get_display (PangoFont *font);
gboolean pango_xft_font_has_char (PangoFont *font,
gunichar wc);
FT_Face pango_xft_font_lock_face (PangoFont *font);
void pango_xft_font_unlock_face (PangoFont *font);
guint pango_xft_font_get_glyph (PangoFont *font,
gunichar wc);
PangoGlyph pango_xft_font_get_unknown_glyph
(PangoFont *font,
gunichar wc);
PangoXftRenderer;
PangoXftRendererClass;
PangoRenderer* pango_xft_renderer_new (Display *display,
int screen);
void pango_xft_renderer_set_draw (PangoXftRenderer *xftrenderer,
XftDraw *draw);
void pango_xft_renderer_set_default_color
(PangoXftRenderer *xftrenderer,
PangoColor *default_color);
void pango_xft_render (XftDraw *draw,
XftColor *color,
PangoFont *font,
PangoGlyphString *glyphs,
gint x,
gint y);
void pango_xft_picture_render (Display *display,
Picture src_picture,
Picture dest_picture,
PangoFont *font,
PangoGlyphString *glyphs,
gint x,
gint y);
void pango_xft_render_transformed (XftDraw *draw,
XftColor *color,
PangoMatrix *matrix,
PangoFont *font,
PangoGlyphString *glyphs,
int x,
int y);
void pango_xft_render_layout_line (XftDraw *draw,
XftColor *color,
PangoLayoutLine *line,
int x,
int y);
void pango_xft_render_layout (XftDraw *draw,
XftColor *color,
PangoLayout *layout,
int x,
int y);
The Xft library is a library for displaying fonts on the X window system; internally it uses the fontconfig library to locate font files, and the FreeType library to load and render fonts. The Xft backend is the recommended Pango font backend for screen display with X. (The Cairo back end is another possibility.)
Using the Xft backend is generally straightforward;
pango_xft_get_context() creates a context for a specified display
and screen. You can then create a PangoLayout with that context
and render it with pango_xft_render_layout(). At a more advanced
level, the low-level fontconfig options used for rendering fonts
can be affected using pango_xft_set_default_substitute(), and
pango_xft_substitute_changed().
A range of functions for drawing pieces of a layout, such as individual layout lines and glyphs strings are provided. You can also directly create a PangoXftRenderer. Finally, in some advanced cases, it is useful to derive from PangoXftRenderer. Deriving from PangoXftRenderer is useful for two reasons. One reason is be to support custom attributes by overriding PangoRendererClass virtual functions like 'prepare_run' or 'draw_shape'. The reason is to customize exactly how the final bits are drawn to the destination by overriding the PangoXftRendererClass virtual functions 'composite_glyphs' and 'composite_trapezoids'.
typedef struct _PangoXftFont PangoXftFont;
PangoXftFont is an implementation of PangoFcFont using the Xft library for rendering. It is used in conjunction with PangoXftFontMap.
typedef struct _PangoXftFontMap PangoXftFontMap;
PangoXftFontMap is an implementation of PangoFcFontMap suitable for the Xft library as the renderer. It is used in to create fonts of type PangoXftFont.
#define PANGO_RENDER_TYPE_XFT "PangoRenderXft"
PANGO_RENDER_TYPE_XFT is deprecated and should not be used in newly-written code.
A string constant that was used to identify shape engines that work
with the Xft backend. See PANGO_RENDER_TYPE_FC for the replacement.
PangoContext* pango_xft_get_context (Display *display, int screen);
Retrieves a PangoContext appropriate for rendering with Xft fonts on the given screen of the given display.
display : |
an X display. |
screen : |
an X screen. |
| Returns : | the new PangoContext. |
PangoFontMap* pango_xft_get_font_map (Display *display, int screen);
Returns the PangoXftFontmap for the given display and screen. The fontmap is owned by Pango and will be valid until the display is closed.
display : |
an X display |
screen : |
the screen number of a screen within display
|
| Returns : | a PangoFontMap object, owned by Pango. |
Since 1.2
void pango_xft_set_default_substitute
(Display *display,
int screen,
PangoXftSubstituteFunc func,
gpointer data,
GDestroyNotify notify);
Sets a function that will be called to do final configuration substitution on a FcPattern before it is used to load the font. This function can be used to do things like set hinting and antialiasing options.
display : |
an X Display |
screen : |
the screen number of a screen within display
|
func : |
function to call to to do final config tweaking on FcPattern objects. |
data : |
data to pass to func
|
notify : |
function to call when data is no longer used.
|
Since 1.2
void (*PangoXftSubstituteFunc) (FcPattern *pattern,
gpointer data);
Function type for doing final config tweaking on prepared FcPatterns.
pattern : |
the FcPattern to tweak. |
data : |
user data. |
void pango_xft_substitute_changed (Display *display,
int screen);
Call this function any time the results of the
default substitution function set with
pango_xft_set_default_substitute() change.
That is, if your substitution function will return different
results for the same input pattern, you must call this function.
display : |
an X Display |
screen : |
the screen number of a screen within display
|
Since 1.2
void pango_xft_shutdown_display (Display *display,
int screen);
Release any resources that have been cached for the
combination of display and screen. Note that when the
X display is closed, resources are released automatically,
without needing to call this function.
display : |
an X display |
screen : |
the screen number of a screen within display
|
Since 1.2
XftFont* pango_xft_font_get_font (PangoFont *font);
Returns the XftFont of a font.
font : |
a PangoFont. |
| Returns : | the XftFont associated to font.
|
Display* pango_xft_font_get_display (PangoFont *font);
Returns the X display of the XftFont of a font.
font : |
a PangoFont. |
| Returns : | the X display of the XftFont associated to font.
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gboolean pango_xft_font_has_char (PangoFont *font, gunichar wc);
pango_xft_font_has_char is deprecated and should not be used in newly-written code.
Determines whether font has a glyph for the codepoint wc.
Use pango_fc_font_has_char() instead.
font : |
a PangoFont for the Xft backend |
wc : |
Unicode codepoint to look up |
| Returns : | TRUE if font has the requested codepoint.
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Since 1.2
FT_Face pango_xft_font_lock_face (PangoFont *font);
pango_xft_font_lock_face is deprecated and should not be used in newly-written code.
Gets the FreeType FT_Face associated with a font,
This face will be kept around until you call
pango_xft_font_unlock_face().
Use pango_fc_font_lock_face() instead.
font : |
a PangoFont. |
| Returns : | the FreeType FT_Face associated with font.
|
Since 1.2
void pango_xft_font_unlock_face (PangoFont *font);
pango_xft_font_unlock_face is deprecated and should not be used in newly-written code.
Releases a font previously obtained with
pango_xft_font_lock_face().
Use pango_fc_font_unlock_face() instead.
font : |
a PangoFont. |
Since 1.2
guint pango_xft_font_get_glyph (PangoFont *font, gunichar wc);
pango_xft_font_get_glyph is deprecated and should not be used in newly-written code.
Gets the glyph index for a given Unicode character
for font. If you only want to determine
whether the font has the glyph, use pango_xft_font_has_char().
Use pango_fc_font_get_glyph() instead.
font : |
a PangoFont for the Xft backend |
wc : |
Unicode codepoint to look up |
| Returns : | the glyph index, or 0, if the Unicode character does not exist in the font. |
Since 1.2
PangoGlyph pango_xft_font_get_unknown_glyph (PangoFont *font, gunichar wc);
pango_xft_font_get_unknown_glyph is deprecated and should not be used in newly-written code.
Returns the index of a glyph suitable for drawing wc as an
unknown character.
Use PANGO_GET_UNKNOWN_GLYPH() instead.
font : |
a PangoFont. |
wc : |
the Unicode character for which a glyph is needed. |
| Returns : | a glyph index into font.
|
typedef struct {
} PangoXftRenderer;
PangoXftRenderer is a subclass of PangoRenderer used for rendering with Pango's Xft backend. It can be used directly, or it can be further subclassed to modify exactly how drawing of individual elements occurs.
Since 1.8
typedef struct {
void (*composite_trapezoids) (PangoXftRenderer *xftrenderer,
PangoRenderPart part,
XTrapezoid *trapezoids,
int n_trapezoids);
void (*composite_glyphs) (PangoXftRenderer *xftrenderer,
XftFont *xft_font,
XftGlyphSpec *glyphs,
int n_glyphs);
} PangoXftRendererClass;
The class structure for PangoXftRenderer
composite_trapezoids () |
draw the specified trapezoids using
the current color and other attributes for part
|
composite_glyphs () |
draw the specified glyphs using the current foreground color and other foreground attributes |
Since 1.8
PangoRenderer* pango_xft_renderer_new (Display *display, int screen);
Create a new PangoXftRenderer to allow rendering Pango objects
with the Xft library. You must call pango_xft_renderer_set_draw() before
using the renderer.
display : |
an X display |
screen : |
the index of the screen for display to which rendering will be done
|
| Returns : | the newly created PangoXftRenderer, which should
be freed with g_object_unref().
|
Since 1.8
void pango_xft_renderer_set_draw (PangoXftRenderer *xftrenderer, XftDraw *draw);
Sets the XftDraw object that the renderer is drawing to. The renderer must not be currently active.
xftrenderer : |
a PangoXftRenderer |
draw : |
a XftDraw |
Since 1.8
void pango_xft_renderer_set_default_color
(PangoXftRenderer *xftrenderer,
PangoColor *default_color);
Sets the default foreground color for a XftRenderer.
xftrenderer : |
a XftRenderer |
default_color : |
the default foreground color |
Since 1.8
void pango_xft_render (XftDraw *draw,
XftColor *color,
PangoFont *font,
PangoGlyphString *glyphs,
gint x,
gint y);
Renders a PangoGlyphString onto an XftDraw object wrapping an X drawable.
draw : |
the XftDraw object. |
color : |
the color in which to draw the string |
font : |
the font in which to draw the string |
glyphs : |
the glyph string to draw |
x : |
the x position of start of string (in pixels) |
y : |
the y position of baseline (in pixels) |
void pango_xft_picture_render (Display *display,
Picture src_picture,
Picture dest_picture,
PangoFont *font,
PangoGlyphString *glyphs,
gint x,
gint y);
Renders a PangoGlyphString onto an Xrender Picture object.
display : |
an X display |
src_picture : |
the source picture to draw the string with |
dest_picture : |
the destination picture to draw the string onto |
font : |
the font in which to draw the string |
glyphs : |
the glyph string to draw |
x : |
the x position of start of string (in pixels) |
y : |
the y position of baseline (in pixels) |
void pango_xft_render_transformed (XftDraw *draw,
XftColor *color,
PangoMatrix *matrix,
PangoFont *font,
PangoGlyphString *glyphs,
int x,
int y);
Renders a PangoGlyphString onto a XftDraw, possibly
transforming the layed-out coordinates through a transformation
matrix. Note that the transformation matrix for font is not
changed, so to produce correct rendering results, the font
must have been loaded using a PangoContext with an identical
transformation matrix to that passed in to this function.
draw : |
an XftDraw |
color : |
the color in which to draw the glyphs |
matrix : |
a PangoMatrix, or NULL to use an identity transformation
|
font : |
the font in which to draw the string |
glyphs : |
the glyph string to draw |
x : |
the x position of the start of the string (in Pango units in user space coordinates) |
y : |
the y position of the baseline (in Pango units in user space coordinates) |
Since 1.8
void pango_xft_render_layout_line (XftDraw *draw,
XftColor *color,
PangoLayoutLine *line,
int x,
int y);
Render a PangoLayoutLine onto a XftDraw
draw : |
an XftDraw |
color : |
the foreground color in which to draw the layout line (may be overridden by color attributes) |
line : |
a PangoLayoutLine |
x : |
the x position of start of string (in Pango units) |
y : |
the y position of baseline (in Pango units) |
Since 1.8
void pango_xft_render_layout (XftDraw *draw,
XftColor *color,
PangoLayout *layout,
int x,
int y);
Render a PangoLayout onto a XftDraw
draw : |
an XftDraw |
color : |
the foreground color in which to draw the layout (may be overridden by color attributes) |
layout : |
a PangoLayout |
x : |
the X position of the left of the layout (in Pango units) |
y : |
the Y position of the top of the layout (in Pango units) |
Since 1.8