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* Ported from libgnomeprint
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* Dirk Luetjens <dirk@luedi.oche.de>
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* Yves Arrouye <Yves.Arrouye@marin.fdn.fr>
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* Lauris Kaplinski <lauris@ximian.com>
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* Copyright 1999-2001 Ximian, Inc. and authors
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#include <glib/gmessages.h>
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#include <glib/gslist.h>
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#include <glib/gtypes.h>
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#include "sp-metric.h"
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* Units and conversion methods used by libgnomeprint.
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* You need those for certain config keys (like paper size), if you are
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* interested in using these (look at gnome-print-config.h for discussion,
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* why you may NOT be interested in paper size).
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* Unit bases define set of mutually unrelated measuring systems (numbers,
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* paper, screen and dimesionless user coordinates). Still, you can convert
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* between those, specifying scaling factors explicitly.
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* Paper (i.e. output) coordinates are taken as absolute real world units.
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* It has some justification, because screen unit (pixel) size changes,
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* if you change screen resolution, while you cannot change output on paper
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* as easily (unless you have thermally contracting paper, of course).
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* The base linear ("absolute") unit is 1/72th of an inch, i.e. the base unit of postscript.
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SP_UNIT_DIMENSIONLESS = (1 << 0), /* For percentages and like */
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SP_UNIT_ABSOLUTE = (1 << 1), /* Real world distances - i.e. mm, cm... */
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SP_UNIT_DEVICE = (1 << 2), /* Pixels in the SVG/CSS sense. */
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SP_UNIT_VOLATILE = (1 << 3) /* em and ex */
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* Units: indexes into sp_units.
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SP_UNIT_SCALE, // 1.0 == 100%
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SP_UNIT_PT, // Postscript points: exactly 72 per inch
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SP_UNIT_PX, // "Pixels" in the CSS sense; though Inkscape assumes a constant 90 per inch.
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SP_UNIT_PERCENT, /* Note: In Inkscape this often means "relative to current value" (for
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users to edit a value), rather than the SVG/CSS use of percentages. */
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SP_UNIT_MM, // millimetres
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SP_UNIT_CM, // centimetres
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SP_UNIT_EM, // font-size of relevant font
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SP_UNIT_EX, // x-height of relevant font
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sp_max_unit_id = SP_UNIT_EX // For bounds-checking in sp_unit_get_by_id.
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* Notice, that for correct menus etc. you have to use
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* ngettext method family yourself. For that reason we
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* do not provide translations in unit names.
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* I also do not know, whether to allow user-created units,
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* because this would certainly confuse textdomain.
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SPUnitId unit_id; /* used as sanity check */
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gdouble unittobase; /* how many base units in this unit */
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SPMetric metric; // the corresponding SPMetric from sp-metrics.h
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guint svg_unit; // the corresponding SVGLengthUnit
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/* When using, you must call "gettext" on them so they're translated */
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gchar const *abbr_plural;
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const SPUnit *sp_unit_get_by_abbreviation (const gchar *abbreviation);
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/* When using, you must call "gettext" on them so they're translated */
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const gchar *sp_unit_get_abbreviation (const SPUnit *unit);
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gchar const *sp_unit_get_plural (SPUnit const *unit);
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SPMetric sp_unit_get_metric(SPUnit const *unit);
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guint sp_unit_get_svg_unit(SPUnit const *unit);
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extern SPUnit const sp_units[];
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inline SPUnit const &
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sp_unit_get_by_id(SPUnitId const id)
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/* inline because the compiler should optimize away the g_return_val_if_fail test in the
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usual case that the argument value is known at compile-time, leaving just
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"return sp_units[constant]". */
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unsigned const ix = unsigned(id);
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g_return_val_if_fail(ix <= sp_max_unit_id, sp_units[SP_UNIT_PX]);
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#define SP_PS_UNIT (&sp_unit_get_by_id(SP_UNIT_PT))
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/** Used solely by units-test.cpp. */
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bool sp_units_table_sane();
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#define SP_UNITS_ALL (SP_UNIT_DIMENSIONLESS | SP_UNIT_ABSOLUTE | SP_UNIT_DEVICE | SP_UNIT_VOLATILE)
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GSList *sp_unit_get_list (guint bases);
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void sp_unit_free_list (GSList *units);
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/* These are pure utility */
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/* Return TRUE if conversion is possible, FALSE if unit bases differ */
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gboolean sp_convert_distance (gdouble *distance, const SPUnit *from, const SPUnit *to);
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/* If either one is NULL, transconverting to/from that base fails */
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/* Generic conversion between volatile units would be useless anyways */
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gdouble sp_convert_distance_full(gdouble const from_dist, SPUnit const &from, SPUnit const &to);
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/* Some more convenience */
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gdouble sp_units_get_pixels(gdouble const units, SPUnit const &unit);
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gdouble sp_pixels_get_units(gdouble const pixels, SPUnit const &unit);
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double angle_to_compass(double angle);
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double angle_from_compass(double angle);
added
removed
src/helper/units.h
