ruby-****@sourc*****
ruby-****@sourc*****
2013年 4月 3日 (水) 14:35:21 JST
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REMOTE_ADDR = 70.49.48.128
REMOTE_HOST =
URL = http://ruby-gnome2.sourceforge.jp/hiki.cgi?tut-gtk2-dancr-rbcatut-dwc
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@@ -213,6 +213,9 @@
(12.3.2.1.2){{br}}
{{br}}
+ Before we continue, lets remind ourselves that Ruby Gtk/Cairo implementation does not support the gradients. We have to fall back to the 'rcairo' and ((*require 'cairo'*)) module. We have already mentioned this in section 12.3.1.2.5 ((<Mask Method|tut-gtk2-dancr-rbcatut-crdrmd#Mask Method>)) and in its subsection (12.3.1.2.5.A1) "Ruby Gtk-Cairo Library Fails To Support Gradient Patterns", where we explain the difference between Ruby Gtk programming environment and non-GUI character based terminal programming environment utilizing Cairo library, a.k.a. '((<rcairo|URL:http://cairo.rubyforge.org/doc/en/>))' directly.
+
+
Gradients describe a progression of colors by setting a start and stop reference location and a series of "stops" along the way. ((<Linear gradients|URL:http://www.cairographics.org/manual/cairo-cairo-pattern-t.html#cairo-pattern-create-linear>)) are built from two points which pass through parallel lines to define the start and stop locations. ((<Radial gradients|URL:http://www.cairographics.org/manual/cairo-cairo-pattern-t.html#cairo-pattern-create-radial>)) are also built from two points, but each has an associated radius of the circle on which to define the start and stop locations. Stops are added to the gradient with ((<cairo_add_color_stop_rgb()|URL:http://www.cairographics.org/manual/cairo-cairo-pattern-t.html#cairo-pattern-add-color-stop-rgb>)) and ((<cairo_add_color_stop_rgba()|URL:http://www.cairographics.org/manual/cairo-cairo-pattern-t.html#cairo-pattern-add-color-stop-rgba>)) which take a color like cairo_set_source_rgb*(), as well as an offset to indicate
where it lies between the reference locations. The colors between adjacent stops are averaged over space to form a smooth blend. Finally, the behavior beyond the reference locations can be controlled with ((<cairo_set_extend()|URL:http://www.cairographics.org/manual/cairo-cairo-pattern-t.html#cairo-pattern-set-extend>)).