ruby-****@sourc*****
ruby-****@sourc*****
2013年 3月 12日 (火) 14:19:30 JST
-------------------------
REMOTE_ADDR = 184.145.80.119
REMOTE_HOST =
URL = http://ruby-gnome2.sourceforge.jp/hiki.cgi?tut-gtk2-dancr
-------------------------
@@ -34,16 +34,15 @@
If you have worked with GTK+ in either its native C, or in its close relative C++ (gtkmm) environments, you may very well be aware of the two different ways graphic imaging and drawing is handled in GTK+. One, the older and original is the plain GTK approach, mostly utilizing the Gdk::Drawable class, which has mostly been replaced by the newer approach utilizing a third party ((*Cairo*)) 2D graphics library ( see: http://cairographics.org/ ).
:Contents At the Glance:
- {{image_left("1201-img01-gtk-backgrounds-s2.png")}}
+ (12.0.1.1){{br}}{{image_left("1201-img01-gtk-backgrounds-s2.png")}}
Let's look at the images here to get an idea what is going to be the starting point of our study in this chapter.
{{br}
Here on the left you see a few examples of plain original GTK approach, utilizing the Gdk::Drawable class. We manage the background image of the drawable widget. In one case the single stretchable image is used, in the other multiple tailed images appear as the background. In either case you are able to use a graphic pen/brush like feature to draw, as well as 'undo' your drawing by pressing delete key.
{{br}}
+ {{image_right("1201-img02-ruby-cairo-is-comming-s2.png")}}
On the right you can see a few very simple Cairo sample programs, that a novice to Ruby GTK/Cairo programming may find in different 'non-Ruby' tutorials on the Internet, and that may seem to be very hard if not impossible to implement in Ruby. Yet, as you can see there is a way!
-
- {{image_right("1201-img02-ruby-cairo-is-comming-s2.png")}}
In this chapter I will attempt to highlight both of these two environments, point out how they cooperate, as well as discuss the circumstances when it looks that either one may be a better choice over the other, and even when due to some, as of yet, unexplained limitations of Ruby GTK/Cairo marriage we need to resort to some peculiar tricks not needed in straight C, or C++ (gtkmm) environments.