1Gnome2::Canvas::main(3)User Contributed Perl DocumentatioGnnome2::Canvas::main(3)
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NAME

6       Gnome2::Canvas::main - A structured graphics canvas
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METHODS

9   widget = Gnome2::Canvas->new
10       Create a new empty canvas in non-antialiased mode.
11
12   widget = Gnome2::Canvas->new_aa
13       Create a new empty canvas in antialiased mode.
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15   boolean = $canvas->aa
16       Returns true if $canvas was created in anti-aliased mode.
17
18   ($bx1, $by1, $bx2, $by2) = Gnome2::Canvas->get_butt_points ($x1, $y1, $x2,
19       $y2, $width, $project)
20       •   $x1 (double)
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22       •   $y1 (double)
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24       •   $x2 (double)
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26       •   $y2 (double)
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28       •   $width (double)
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30       •   $project (integer)
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32   (wx, wy) = $canvas->c2w ($cx, $cy)
33       •   $cx (integer)
34
35       •   $cy (integer)
36
37   boolean = $canvas->get_center_scroll_region
38   $canvas->set_center_scroll_region ($center_scroll_region)
39       •   $center_scroll_region (boolean)
40
41   list = $canvas->get_color ($spec)
42       •   $spec (string)
43
44       Returns an integer indicating the success of the color allocation and a
45       GdkColor.
46
47   unsigned = $canvas->get_color_pixel ($rgba)
48       •   $rgba (integer)
49
50   rgbdither = $canvas->get_dither
51   $canvas->set_dither ($dither)
52       •   $dither (Gtk2::Gdk::RgbDither)
53
54   item = $canvas->get_item_at ($x, $y)
55       •   $x (double)
56
57       •   $y (double)
58
59   ($mx1, $my1, $mx2, $my2) = Gnome2::Canvas->get_miter_points ($x1, $y1, $x2,
60       $y2, $x3, $y3, $width)
61       •   $x1 (double)
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63       •   $y1 (double)
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65       •   $x2 (double)
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67       •   $y2 (double)
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69       •   $x3 (double)
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71       •   $y3 (double)
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73       •   $width (double)
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75   double = $canvas->get_pixels_per_unit
76       Fetch $canvas' scale factor.
77
78   $canvas->set_pixels_per_unit ($n)
79       •   $n (double)
80
81       Set the zooming factor of $canvas by specifying the number of screen
82       pixels that correspond to one canvas unit.
83
84   double = Gnome2::Canvas->polygon_to_point ($poly_ref, $x, $y)
85       •   $poly_ref (arrayref) coordinate pairs that make up the polygon
86
87       •   $x (double)
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89       •   $y (double)
90
91       Return the distance from the point $x,$y to the polygon described by
92       the vertices in $poly_ref, or zero if the point is inside the polygon.
93
94   $canvas->request_redraw ($x1, $y1, $x2, $y2)
95       •   $x1 (integer)
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97       •   $y1 (integer)
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99       •   $x2 (integer)
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101       •   $y2 (integer)
102
103   group = $canvas->root
104   (cx, cy) = $canvas->get_scroll_offsets
105   (x1, y1, x2, y2) = $canvas->get_scroll_region
106   $canvas->set_scroll_region ($x1, $y1, $x2, $y2)
107       •   $x1 (double)
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109       •   $y1 (double)
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111       •   $x2 (double)
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113       •   $y2 (double)
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115   $canvas->scroll_to ($cx, $cy)
116       •   $cx (integer)
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118       •   $cy (integer)
119
120   $canvas->set_stipple_origin ($gc)
121       •   $gc (Gtk2::Gdk::GC)
122
123   $canvas->update_now
124   (cx, cy) = $canvas->w2c ($wx, $wy)
125       •   $wx (double)
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127       •   $wy (double)
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129   $affine = $canvas->w2c_affine
130       Fetch the affine transform that converts from world coordinates to
131       canvas pixel coordinates.
132
133       Note: This method was completely broken for all
134       $Gnome2::Canvas::VERSION < 1.002.
135
136   (cx, cy) = $canvas->w2c_d ($wx, $wy)
137       •   $wx (double)
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139       •   $wy (double)
140
141   (worldx, worldy) = $canvas->window_to_world ($winx, $winy)
142       •   $winx (double)
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144       •   $winy (double)
145
146   (winx, winy) = $canvas->world_to_window ($worldx, $worldy)
147       •   $worldx (double)
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149       •   $worldy (double)
150

ENUMS AND FLAGS

152   enum Gtk2::Gdk::RgbDither
153       •   'none' / 'GDK_RGB_DITHER_NONE'
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155       •   'normal' / 'GDK_RGB_DITHER_NORMAL'
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157       •   'max' / 'GDK_RGB_DITHER_MAX'
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SEE ALSO

160       Gnome2::Canvas
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163       Copyright (C) 2003-2004 by the Gtk2-Perl Team.
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165       This software is licensed under the LGPL; see Gnome2::Canvas for a full
166       notice.
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170perl v5.34.0                      2021-07-22           Gnome2::Canvas::main(3)
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