CtkPrintContext

CtkPrintContext — Encapsulates context for drawing pages

Functions

Types and Values

Object Hierarchy

    GObject
    ╰── CtkPrintContext

Includes

#include <ctk/ctk.h>

Description

A CtkPrintContext encapsulates context information that is required when drawing pages for printing, such as the cairo context and important parameters like page size and resolution. It also lets you easily create PangoLayout and PangoContext objects that match the font metrics of the cairo surface.

CtkPrintContext objects gets passed to the “begin-print”, “end-print”, “request-page-setup” and “draw-page” signals on the CtkPrintOperation.

Using CtkPrintContext in a “draw-page” callback

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static void
draw_page (CtkPrintOperation *operation,
	   CtkPrintContext   *context,
	   int                page_nr)
{
  cairo_t *cr;
  PangoLayout *layout;
  PangoFontDescription *desc;

  cr = ctk_print_context_get_cairo_context (context);

  // Draw a red rectangle, as wide as the paper (inside the margins)
  cairo_set_source_rgb (cr, 1.0, 0, 0);
  cairo_rectangle (cr, 0, 0, ctk_print_context_get_width (context), 50);

  cairo_fill (cr);

  // Draw some lines
  cairo_move_to (cr, 20, 10);
  cairo_line_to (cr, 40, 20);
  cairo_arc (cr, 60, 60, 20, 0, M_PI);
  cairo_line_to (cr, 80, 20);

  cairo_set_source_rgb (cr, 0, 0, 0);
  cairo_set_line_width (cr, 5);
  cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
  cairo_set_line_join (cr, CAIRO_LINE_JOIN_ROUND);

  cairo_stroke (cr);

  // Draw some text
  layout = ctk_print_context_create_pango_layout (context);
  pango_layout_set_text (layout, "Hello World! Printing is easy", -1);
  desc = pango_font_description_from_string ("sans 28");
  pango_layout_set_font_description (layout, desc);
  pango_font_description_free (desc);

  cairo_move_to (cr, 30, 20);
  pango_cairo_layout_path (cr, layout);

  // Font Outline
  cairo_set_source_rgb (cr, 0.93, 1.0, 0.47);
  cairo_set_line_width (cr, 0.5);
  cairo_stroke_preserve (cr);

  // Font Fill
  cairo_set_source_rgb (cr, 0, 0.0, 1.0);
  cairo_fill (cr);

  g_object_unref (layout);
}

Printing support was added in CTK+ 2.10.

Functions

ctk_print_context_get_cairo_context ()

cairo_t *
ctk_print_context_get_cairo_context (CtkPrintContext *context);

Obtains the cairo context that is associated with the CtkPrintContext.

Parameters

context

a CtkPrintContext

 

Returns

the cairo context of context .

[transfer none]

Since: 2.10


ctk_print_context_set_cairo_context ()

void
ctk_print_context_set_cairo_context (CtkPrintContext *context,
                                     cairo_t *cr,
                                     double dpi_x,
                                     double dpi_y);

Sets a new cairo context on a print context.

This function is intended to be used when implementing an internal print preview, it is not needed for printing, since CTK+ itself creates a suitable cairo context in that case.

Parameters

context

a CtkPrintContext

 

cr

the cairo context

 

dpi_x

the horizontal resolution to use with cr

 

dpi_y

the vertical resolution to use with cr

 

Since: 2.10


ctk_print_context_get_page_setup ()

CtkPageSetup *
ctk_print_context_get_page_setup (CtkPrintContext *context);

Obtains the CtkPageSetup that determines the page dimensions of the CtkPrintContext.

Parameters

context

a CtkPrintContext

 

Returns

the page setup of context .

[transfer none]

Since: 2.10


ctk_print_context_get_width ()

gdouble
ctk_print_context_get_width (CtkPrintContext *context);

Obtains the width of the CtkPrintContext, in pixels.

Parameters

context

a CtkPrintContext

 

Returns

the width of context

Since: 2.10


ctk_print_context_get_height ()

gdouble
ctk_print_context_get_height (CtkPrintContext *context);

Obtains the height of the CtkPrintContext, in pixels.

Parameters

context

a CtkPrintContext

 

Returns

the height of context

Since: 2.10


ctk_print_context_get_dpi_x ()

gdouble
ctk_print_context_get_dpi_x (CtkPrintContext *context);

Obtains the horizontal resolution of the CtkPrintContext, in dots per inch.

Parameters

context

a CtkPrintContext

 

Returns

the horizontal resolution of context

Since: 2.10


ctk_print_context_get_dpi_y ()

gdouble
ctk_print_context_get_dpi_y (CtkPrintContext *context);

Obtains the vertical resolution of the CtkPrintContext, in dots per inch.

Parameters

context

a CtkPrintContext

 

Returns

the vertical resolution of context

Since: 2.10


ctk_print_context_get_pango_fontmap ()

PangoFontMap *
ctk_print_context_get_pango_fontmap (CtkPrintContext *context);

Returns a PangoFontMap that is suitable for use with the CtkPrintContext.

Parameters

context

a CtkPrintContext

 

Returns

the font map of context .

[transfer none]

Since: 2.10


ctk_print_context_create_pango_context ()

PangoContext *
ctk_print_context_create_pango_context
                               (CtkPrintContext *context);

Creates a new PangoContext that can be used with the CtkPrintContext.

Parameters

context

a CtkPrintContext

 

Returns

a new Pango context for context .

[transfer full]

Since: 2.10


ctk_print_context_create_pango_layout ()

PangoLayout *
ctk_print_context_create_pango_layout (CtkPrintContext *context);

Creates a new PangoLayout that is suitable for use with the CtkPrintContext.

Parameters

context

a CtkPrintContext

 

Returns

a new Pango layout for context .

[transfer full]

Since: 2.10


ctk_print_context_get_hard_margins ()

gboolean
ctk_print_context_get_hard_margins (CtkPrintContext *context,
                                    gdouble *top,
                                    gdouble *bottom,
                                    gdouble *left,
                                    gdouble *right);

Obtains the hardware printer margins of the CtkPrintContext, in units.

Parameters

context

a CtkPrintContext

 

top

top hardware printer margin.

[out]

bottom

bottom hardware printer margin.

[out]

left

left hardware printer margin.

[out]

right

right hardware printer margin.

[out]

Returns

TRUE if the hard margins were retrieved

Since: 2.20

Types and Values

CtkPrintContext

typedef struct _CtkPrintContext CtkPrintContext;