Pango::Renderer Class Reference

Detailed Description
Pango::Renderer is a base class that contains the necessary logic for rendering a Pango::Layout or Pango::LayoutLine.By subclassing Pango::Renderer and overriding operations such as draw_glyphs and draw_rectangle, renderers for particular font backends and destinations can be created.
Public Member Functions | |
void | activate () |
Does initial setup before rendering operations on renderer. | |
void | deactivate () |
Cleans up after rendering operations on renderer. | |
void | draw_error_underline (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. | |
void | draw_glyph (const Glib::RefPtr<Font>& font, Glyph glyph, double x, double y) |
Draws a single glyph with coordinates in device space. | |
void | draw_glyphs (const Glib::RefPtr<Font>& font, const GlyphString& glyphs, int x, int y) |
Draws the glyphs in glyphs with the specified Pango::Renderer. | |
void | draw_layout (const Glib::RefPtr<Layout>& layout, int x, int y) |
Draws layout with the specified Pango::Renderer. | |
void | draw_layout_line (const Glib::RefPtr<LayoutLine>& line, int x, int y) |
Draws line with the specified Pango::Renderer. | |
void | draw_rectangle (RenderPart part, int x, int y, int width, int height) |
Draws an axis-aligned rectangle in user space coordinates with the specified Pango::Renderer. | |
void | draw_trapezoid (RenderPart 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 Pango::Renderer; coordinates are in device space. | |
Color | get_color (RenderPart part) const |
Gets the current rendering color for the specified part. | |
Glib::RefPtr<const Layout> | get_layout () const |
Gets the layout currently being rendered using renderer. | |
Glib::RefPtr<Layout> | get_layout () |
Gets the layout currently being rendered using renderer. | |
Glib::RefPtr<const LayoutLine> | get_layout_line () const |
Gets the layout line currently being rendered using renderer. | |
Glib::RefPtr<LayoutLine> | get_layout_line () |
Gets the layout line currently being rendered using renderer. | |
Matrix | get_matrix () const |
const PangoRenderer* | gobj () const |
Provides access to the underlying C GObject. | |
PangoRenderer* | gobj () |
Provides access to the underlying C GObject. | |
PangoRenderer* | gobj_copy () |
Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs. | |
void | part_changed (RenderPart 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. | |
void | set_color (RenderPart part, const Color& color) |
Sets the color for part of the rendering. | |
void | set_matrix (const Matrix& matrix) |
Sets the transformation matrix that will be applied when rendering. | |
virtual | ~Renderer () |
Related Functions | |
(Note that these are not member functions.) | |
Glib::RefPtr<Pango::Renderer> | wrap (PangoRenderer* object, bool take_copy=false) |
A Glib::wrap() method for this object. |
Constructor & Destructor Documentation
virtual Pango::Renderer::~Renderer | ( | ) | [virtual] |
Member Function Documentation
void Pango::Renderer::activate | ( | ) |
Does initial setup before rendering operations on renderer.
deactivate() should be called when done drawing. Calls such as draw_layout() automatically activate the layout before drawing on it. Calls to activate() and deactivate() can be nested and the renderer will only be initialized and deinitialized once.
Since: 1.8
void Pango::Renderer::deactivate | ( | ) |
void Pango::Renderer::draw_error_underline | ( | 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 activate() to activate a renderer.
Since: 1.8
void Pango::Renderer::draw_glyph | ( | const Glib::RefPtr<Font>& | font, | |
Glyph | glyph, | |||
double | x, | |||
double | y | |||
) |
Draws a single glyph with coordinates in device space.
Since: 1.8
- Parameters:
-
font A Pango::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.
void Pango::Renderer::draw_glyphs | ( | const Glib::RefPtr<Font>& | font, | |
const GlyphString& | glyphs, | |||
int | x, | |||
int | y | |||
) |
Draws the glyphs in glyphs with the specified Pango::Renderer.
Since: 1.8
- Parameters:
-
font A Pango::Font. glyphs A Pango::GlyphString. 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.
void Pango::Renderer::draw_layout | ( | const Glib::RefPtr<Layout>& | layout, | |
int | x, | |||
int | y | |||
) |
Draws layout with the specified Pango::Renderer.
Since: 1.8
- Parameters:
-
layout A Pango::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.
void Pango::Renderer::draw_layout_line | ( | const Glib::RefPtr<LayoutLine>& | line, | |
int | x, | |||
int | y | |||
) |
Draws line with the specified Pango::Renderer.
Since: 1.8
- Parameters:
-
line A Pango::LayoutLine. 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.
void Pango::Renderer::draw_rectangle | ( | RenderPart | part, | |
int | x, | |||
int | y, | |||
int | width, | |||
int | height | |||
) |
Draws an axis-aligned rectangle in user space coordinates with the specified Pango::Renderer.
This should be called while renderer is already active. Use activate() to activate a renderer.
Since: 1.8
- Parameters:
-
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.
void Pango::Renderer::draw_trapezoid | ( | RenderPart | 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 Pango::Renderer; coordinates are in device space.
Since: 1.8
- Parameters:
-
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.
Color Pango::Renderer::get_color | ( | RenderPart | part | ) | const |
Gets the current rendering color for the specified part.
- Parameters:
-
part The part to get the color for.
- Returns:
- The color for the specified part, or
0
if it hasn't been set and should be inherited from the environment.
Glib::RefPtr<const Layout> Pango::Renderer::get_layout | ( | ) | const |
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
0
if no layout is being rendered using renderer at this time.
Glib::RefPtr<Layout> Pango::Renderer::get_layout | ( | ) |
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
0
if no layout is being rendered using renderer at this time.
Glib::RefPtr<const LayoutLine> Pango::Renderer::get_layout_line | ( | ) | const |
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
0
if no layout line is being rendered using renderer at this time.
Glib::RefPtr<LayoutLine> Pango::Renderer::get_layout_line | ( | ) |
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
0
if no layout line is being rendered using renderer at this time.
Matrix Pango::Renderer::get_matrix | ( | ) | const |
const PangoRenderer* Pango::Renderer::gobj | ( | ) | const [inline] |
PangoRenderer* Pango::Renderer::gobj | ( | ) | [inline] |
PangoRenderer* Pango::Renderer::gobj_copy | ( | ) |
Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.
void Pango::Renderer::part_changed | ( | RenderPart | 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 Pango::Renderer was to add a stipple option for drawing underlines, it needs to call
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 set_color())
Since: 1.8
- Parameters:
-
part The part for which rendering has changed.
void Pango::Renderer::set_color | ( | RenderPart | part, | |
const Color& | color | |||
) |
Sets the color for part of the rendering.
Since: 1.8
- Parameters:
-
part The part to change the color of. color The new color or 0
to unset the current color.
void Pango::Renderer::set_matrix | ( | const Matrix& | matrix | ) |
Sets the transformation matrix that will be applied when rendering.
Since: 1.8
- Parameters:
-
matrix A Pango::Matrix, or 0
to unset any existing matrix. (No matrix set is the same as setting the identity matrix.).
Friends And Related Function Documentation
Glib::RefPtr<Pango::Renderer> wrap | ( | PangoRenderer * | object, | |
bool | take_copy = false | |||
) | [related] |
A Glib::wrap() method for this object.
- Parameters:
-
object The C instance. take_copy False if the result should take ownership of the C instance. True if it should take a new copy or ref.
- Returns:
- A C++ instance that wraps this C instance.
The documentation for this class was generated from the following file: