Top |
Functions
void | pango_renderer_draw_layout () |
void | pango_renderer_draw_layout_line () |
void | pango_renderer_draw_glyphs () |
void | pango_renderer_draw_glyph_item () |
void | pango_renderer_draw_rectangle () |
void | pango_renderer_draw_error_underline () |
void | pango_renderer_draw_trapezoid () |
void | pango_renderer_draw_glyph () |
void | pango_renderer_activate () |
void | pango_renderer_deactivate () |
void | pango_renderer_part_changed () |
void | pango_renderer_set_color () |
PangoColor * | pango_renderer_get_color () |
void | pango_renderer_set_alpha () |
guint16 | pango_renderer_get_alpha () |
void | pango_renderer_set_matrix () |
const PangoMatrix * | pango_renderer_get_matrix () |
PangoLayout * | pango_renderer_get_layout () |
PangoLayoutLine * | pango_renderer_get_layout_line () |
Types and Values
struct | PangoRenderer |
enum | PangoRenderPart |
#define | PANGO_TYPE_RENDER_PART |
struct | PangoRendererClass |
Description
PangoRenderer is a base class that contains the necessary logic for
rendering a PangoLayout or PangoLayoutLine. By subclassing
PangoRenderer and overriding operations such as draw_glyphs
and
draw_rectangle
, renderers for particular font backends and
destinations can be created.
Functions
pango_renderer_draw_layout ()
void pango_renderer_draw_layout (PangoRenderer *renderer
,PangoLayout *layout
,int x
,int y
);
Draws layout
with the specified PangoRenderer.
Parameters
renderer |
||
layout |
||
x |
X position of left edge of baseline, in user space coordinates in Pango units. |
|
y |
Y position of left edge of baseline, in user space coordinates in Pango units. |
Since: 1.8
pango_renderer_draw_layout_line ()
void pango_renderer_draw_layout_line (PangoRenderer *renderer
,PangoLayoutLine *line
,int x
,int y
);
Draws line
with the specified PangoRenderer.
Parameters
renderer |
||
line |
||
x |
X position of left edge of baseline, in user space coordinates in Pango units. |
|
y |
Y position of left edge of baseline, in user space coordinates in Pango units. |
Since: 1.8
pango_renderer_draw_glyphs ()
void pango_renderer_draw_glyphs (PangoRenderer *renderer
,PangoFont *font
,PangoGlyphString *glyphs
,int x
,int y
);
Draws the glyphs in glyphs
with the specified PangoRenderer.
Parameters
renderer |
||
font |
||
glyphs |
||
x |
X position of left edge of baseline, in user space coordinates in Pango units. |
|
y |
Y position of left edge of baseline, in user space coordinates in Pango units. |
Since: 1.8
pango_renderer_draw_glyph_item ()
void pango_renderer_draw_glyph_item (PangoRenderer *renderer
,const char *text
,PangoGlyphItem *glyph_item
,int x
,int y
);
Draws the glyphs in glyph_item
with the specified PangoRenderer,
embedding the text associated with the glyphs in the output if the
output format supports it (PDF for example).
Note that text
is the start of the text for layout, which is then
indexed by
.glyph_item->item->offset
If text
is NULL
, this simply calls pango_renderer_draw_glyphs()
.
The default implementation of this method simply falls back to
pango_renderer_draw_glyphs()
.
Parameters
renderer |
||
text |
the UTF-8 text that |
[allow-none] |
glyph_item |
||
x |
X position of left edge of baseline, in user space coordinates in Pango units. |
|
y |
Y position of left edge of baseline, in user space coordinates in Pango units. |
Since: 1.22
pango_renderer_draw_rectangle ()
void pango_renderer_draw_rectangle (PangoRenderer *renderer
,PangoRenderPart part
,int x
,int y
,int width
,int height
);
Draws an axis-aligned rectangle in user space coordinates with the specified PangoRenderer.
This should be called while renderer
is already active. Use
pango_renderer_activate()
to activate a renderer.
Parameters
renderer |
||
part |
type of object this rectangle is part of |
|
x |
X position at which to draw rectangle, in user space coordinates in Pango units |
|
y |
Y position at which to draw rectangle, in user space coordinates in Pango units |
|
width |
width of rectangle in Pango units in user space coordinates |
|
height |
height of rectangle in Pango units in user space coordinates |
Since: 1.8
pango_renderer_draw_error_underline ()
void pango_renderer_draw_error_underline (PangoRenderer *renderer
,int x
,int y
,int width
,int height
);
Draw a squiggly line that approximately covers the given rectangle in the style of an underline used to indicate a spelling error. (The width of the underline is rounded to an integer number of up/down segments and the resulting rectangle is centered in the original rectangle)
This should be called while renderer
is already active. Use
pango_renderer_activate()
to activate a renderer.
Parameters
renderer |
||
x |
X coordinate of underline, in Pango units in user coordinate system |
|
y |
Y coordinate of underline, in Pango units in user coordinate system |
|
width |
width of underline, in Pango units in user coordinate system |
|
height |
height of underline, in Pango units in user coordinate system |
Since: 1.8
pango_renderer_draw_trapezoid ()
void pango_renderer_draw_trapezoid (PangoRenderer *renderer
,PangoRenderPart part
,double y1_
,double x11
,double x21
,double y2
,double x12
,double x22
);
Draws a trapezoid with the parallel sides aligned with the X axis using the given PangoRenderer; coordinates are in device space.
Parameters
renderer |
||
part |
type of object this trapezoid is part of |
|
y1_ |
Y coordinate of top of trapezoid |
|
x11 |
X coordinate of left end of top of trapezoid |
|
x21 |
X coordinate of right end of top of trapezoid |
|
y2 |
Y coordinate of bottom of trapezoid |
|
x12 |
X coordinate of left end of bottom of trapezoid |
|
x22 |
X coordinate of right end of bottom of trapezoid |
Since: 1.8
pango_renderer_draw_glyph ()
void pango_renderer_draw_glyph (PangoRenderer *renderer
,PangoFont *font
,PangoGlyph glyph
,double x
,double y
);
Draws a single glyph with coordinates in device space.
Parameters
renderer |
||
font |
||
glyph |
the glyph index of a single glyph |
|
x |
X coordinate of left edge of baseline of glyph |
|
y |
Y coordinate of left edge of baseline of glyph |
Since: 1.8
pango_renderer_activate ()
void
pango_renderer_activate (PangoRenderer *renderer
);
Does initial setup before rendering operations on renderer
.
pango_renderer_deactivate()
should be called when done drawing.
Calls such as pango_renderer_draw_layout()
automatically
activate the layout before drawing on it. Calls to
pango_renderer_activate()
and pango_renderer_deactivate()
can
be nested and the renderer will only be initialized and
deinitialized once.
Since: 1.8
pango_renderer_deactivate ()
void
pango_renderer_deactivate (PangoRenderer *renderer
);
Cleans up after rendering operations on renderer
. See
docs for pango_renderer_activate()
.
Since: 1.8
pango_renderer_part_changed ()
void pango_renderer_part_changed (PangoRenderer *renderer
,PangoRenderPart part
);
Informs Pango that the way that the rendering is done
for part
has changed in a way that would prevent multiple
pieces being joined together into one drawing call. For
instance, if a subclass of PangoRenderer was to add a stipple
option for drawing underlines, it needs to call
1 |
pango_renderer_part_changed (render, PANGO_RENDER_PART_UNDERLINE); |
When the stipple changes or underlines with different stipples
might be joined together. Pango automatically calls this for
changes to colors. (See pango_renderer_set_color()
)
Since: 1.8
pango_renderer_set_color ()
void pango_renderer_set_color (PangoRenderer *renderer
,PangoRenderPart part
,const PangoColor *color
);
Sets the color for part of the rendering.
Also see pango_renderer_set_alpha()
.
Parameters
renderer |
||
part |
the part to change the color of |
|
color |
the new color or |
[allow-none] |
Since: 1.8
pango_renderer_get_color ()
PangoColor * pango_renderer_get_color (PangoRenderer *renderer
,PangoRenderPart part
);
Gets the current rendering color for the specified part.
Returns
the color for the
specified part, or NULL
if it hasn't been set and should be
inherited from the environment.
[transfer none][nullable]
Since: 1.8
pango_renderer_set_alpha ()
void pango_renderer_set_alpha (PangoRenderer *renderer
,PangoRenderPart part
,guint16 alpha
);
Sets the alpha for part of the rendering.
Note that the alpha may only be used if a color is
specified for part
as well.
Parameters
renderer |
||
part |
the part to set the alpha for |
|
alpha |
an alpha value between 1 and 65536, or 0 to unset the alpha |
Since: 1.38
pango_renderer_get_alpha ()
guint16 pango_renderer_get_alpha (PangoRenderer *renderer
,PangoRenderPart part
);
Gets the current alpha for the specified part.
Returns
the alpha for the specified part, or 0 if it hasn't been set and should be inherited from the environment.
Since: 1.38
pango_renderer_set_matrix ()
void pango_renderer_set_matrix (PangoRenderer *renderer
,const PangoMatrix *matrix
);
Sets the transformation matrix that will be applied when rendering.
Parameters
renderer |
||
matrix |
a PangoMatrix, or |
[allow-none] |
Since: 1.8
pango_renderer_get_matrix ()
const PangoMatrix *
pango_renderer_get_matrix (PangoRenderer *renderer
);
Gets the transformation matrix that will be applied when
rendering. See pango_renderer_set_matrix()
.
Returns
the matrix, or NULL
if no matrix has
been set (which is the same as the identity matrix). The returned
matrix is owned by Pango and must not be modified or freed.
[nullable]
Since: 1.8
pango_renderer_get_layout ()
PangoLayout *
pango_renderer_get_layout (PangoRenderer *renderer
);
Gets the layout currently being rendered using renderer
.
Calling this function only makes sense from inside a subclass's
methods, like in its draw_shape() for example.
The returned layout should not be modified while still being rendered.
Returns
the layout, or NULL
if
no layout is being rendered using renderer
at this time.
[transfer none][nullable]
Since: 1.20
pango_renderer_get_layout_line ()
PangoLayoutLine *
pango_renderer_get_layout_line (PangoRenderer *renderer
);
Gets the layout line currently being rendered using renderer
.
Calling this function only makes sense from inside a subclass's
methods, like in its draw_shape() for example.
The returned layout line should not be modified while still being rendered.
Returns
the layout line, or NULL
if no layout line is being rendered using renderer
at this time.
[transfer none][nullable]
Since: 1.20
Types and Values
struct PangoRenderer
struct PangoRenderer { PangoMatrix *matrix; /* May be NULL */ };
PangoRenderer is a base class for objects that are used to render Pango objects such as PangoGlyphString and PangoLayout.
Members
PangoMatrix * |
the current transformation matrix for
the Renderer; may be |
[nullable] |
Since: 1.8
enum PangoRenderPart
PangoRenderPart defines different items to render for such purposes as setting colors.
Since: 1.8
struct PangoRendererClass
struct PangoRendererClass { /* All of the following have default implementations * and take as coordinates user coordinates in Pango units */ void (*draw_glyphs) (PangoRenderer *renderer, PangoFont *font, PangoGlyphString *glyphs, int x, int y); void (*draw_rectangle) (PangoRenderer *renderer, PangoRenderPart part, int x, int y, int width, int height); void (*draw_error_underline) (PangoRenderer *renderer, int x, int y, int width, int height); /* Nothing is drawn for shaped glyphs unless this is implemented */ void (*draw_shape) (PangoRenderer *renderer, PangoAttrShape *attr, int x, int y); /* These two must be implemented and take coordinates in * device space as doubles. */ void (*draw_trapezoid) (PangoRenderer *renderer, PangoRenderPart part, double y1_, double x11, double x21, double y2, double x12, double x22); void (*draw_glyph) (PangoRenderer *renderer, PangoFont *font, PangoGlyph glyph, double x, double y); /* Notification of change in rendering attributes */ void (*part_changed) (PangoRenderer *renderer, PangoRenderPart part); /* Paired around drawing operations */ void (*begin) (PangoRenderer *renderer); void (*end) (PangoRenderer *renderer); /* Hooks into the details of layout rendering */ void (*prepare_run) (PangoRenderer *renderer, PangoLayoutRun *run); /* All of the following have default implementations * and take as coordinates user coordinates in Pango units */ void (*draw_glyph_item) (PangoRenderer *renderer, const char *text, PangoGlyphItem *glyph_item, int x, int y); };
Class structure for PangoRenderer.
Members
draws a PangoGlyphString |
||
draws a rectangle |
||
draws a squiggly line that approximately covers the given rectangle in the style of an underline used to indicate a spelling error. |
||
draw content for a glyph shaped with PangoAttrShape.
|
||
draws a trapezoidal filled area |
||
draws a single glyph |
||
do renderer specific processing when rendering attributes change |
||
Do renderer-specific initialization before drawing |
||
Do renderer-specific cleanup after drawing |
||
updates the renderer for a new run |
||
draws a PangoGlyphItem |
Since: 1.8