1Gtk2::Gdk::Pixbuf::DrawU:s:eCracChoen(t3r)ibuted Perl DoGctukm2e:n:tGadtki:o:nPixbuf::Draw::Cache(3)
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NAME

6       Gtk2::Gdk::Pixbuf::Draw::Cache - Cache for drawing scaled pixbufs
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HIERARCHY

9         Glib::Boxed
10         +----Gtk2::Gdk::Pixbuf::Draw::Cache
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DESCRIPTION

13       Gtk2::Gdk::Pixbuf::Draw::Cache provides a cache that should be used by
14       the Gtk2::ImageView::Tool when redrawing the Gtk2::ImageView.
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METHODS

17   cache = Gtk2::Gdk::Pixbuf::Draw::Cache->new
18           Creates a new pixbuf draw cache.
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20       Returns
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22       a new Gtk2::Gdk::Pixbuf::Draw::Cache
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24   $cache->draw ($opts, $drawable)
25           ·   $opts (Gtk2::Gdk::Pixbuf::Draw::Opts)
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27           ·   $drawable (Gtk2::Gdk::Drawable)
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29           Redraws the area specified in the pixbuf draw options in an
30           efficient way by using caching.
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32           cache : a GdkPixbufDrawCache
33           opts : the Gtk2::Gdk::Pixbuf::Draw::Opts to use in this draw
34           drawable : a GdkDrawable to draw on
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36   $cache->free
37           Deallocates a pixbuf draw cache and all its data.
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39   $cache->invalidate
40           Force the pixbuf draw cache to scale the pixbuf at the next draw.
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42           Gtk2::Gdk::Pixbuf::Draw::Cache tries to minimize the number of
43           scale operations needed by caching the last drawn pixbuf. It would
44           be inefficient to check the individual pixels inside the pixbuf so
45           it assumes that if the memory address of the pixbuf has not
46           changed, then the cache is good to use.
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48           However, when the image data is modified, this assumtion breaks,
49           which is why this method must be used to tell draw cache about it.
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51   method = Gtk2::Gdk::Pixbuf::Draw::Cache->get_method ($old, $new)
52           ·   $old (Gtk2::Gdk::Pixbuf::Draw::Opts)
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54           ·   $new (Gtk2::Gdk::Pixbuf::Draw::Opts)
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56           Gets the fastest method to draw the specified draw options. old is
57           assumed to be the last PixbufDrawOpts used and new is the one to
58           use this time.
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60           old : the last draw options used
61           new : the current draw options
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63       Returns
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65       the best draw method to use to draw
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ENUMS AND FLAGS

68   enum Gtk2::Gdk::Pixbuf::Draw::Method
69       ·   'scale' / 'GDK_PIXBUF_DRAW_METHOD_SCALE'
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71       ·   'contains' / 'GDK_PIXBUF_DRAW_METHOD_CONTAINS'
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73       ·   'scroll' / 'GDK_PIXBUF_DRAW_METHOD_SCROLL'
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SEE ALSO

76       Gtk2::ImageView, Glib::Boxed
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79       Copyright (C) 2007 by Jeffrey Ratcliffe.
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81       This software is licensed under the GPL-3; see Gtk2::ImageView for a
82       full notice.
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POD ERRORS

85       Hey! The above document had some coding errors, which are explained
86       below:
87
88       Around line 31:
89           You forgot a '=back' before '=head3'
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91       Around line 40:
92           =back without =over
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94       Around line 117:
95           You forgot a '=back' before '=head3'
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97       Around line 126:
98           =back without =over
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102perl v5.12.0                      2010-05-02 Gtk2::Gdk::Pixbuf::Draw::Cache(3)
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