From: Bill Kelly <billk@...>
Date: 2003-04-10T02:20:58+09:00
Subject: Re: [Q] Ruby for graphics

Hi Dominik and Neils,

From: "Dominik Werder" <dwerder@gmx.net>
>
> I would like to do some graphics programming on my own, but I don't know 
> which API to use..
> May I ask you what software you use and on which OS?

From: "niels wolf" <k-zimir@gmx.net>
>
> hm, just some stupid question. new to ruby. what is to use for graphic
> manipulation??


I'm personally using RUDL (Ruby bindings to libsdl:
[ http://froukepc.dhs.org/rudl/ ]), and also a little OpenGL.

Currently the RUDL FAQ lists some problems running under
non-windows operating systems.  I'm using Ruby 1.6.6 on win2k.

However I believe the OpenGL bindings definitely work on Linux.  If
you're on Windows, and using the Pragmatic Programmers installer for
Ruby, OpenGL support should already be installed for you.  Otherwise,
see the RAA: [ http://raa.ruby-lang.org/list.rhtml?name=opengl ]

RUDL provides support for loading images as textures or sprites,
drawing them to the screen, full-screen mode or windowed, some 
basic graphics primitives, and I think audio and joystick support
(but I haven't tried the latter two.)

Here's one of the simpler examples that comes with RUDL, for
loading a sprite and bouncing it around on the screen:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
require 'RUDL'; include RUDL

display = DisplaySurface.new([640, 480])
ball = Surface.load_new('media/bounce.bmp')
lastrect = [0,0,0,0]

loop {
  break if EventQueue.poll.type == QuitEvent
  pos = [(Timer.ticks%1024-512).abs, ((Timer.ticks+200)%704-352).abs]
  rect = display.blit(ball, pos)
  display.update([rect.union(lastrect)])
  display.fill([0, 0, 0], lastrect = rect)
}

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


As for image manipulation libraries, I haven't used any with
Ruby yet.  Last I looked, there appeared to be some available
for Linux (imlib2 bindings, ImageMagick bindings, etc.) but I
didn't see much for Windows.  That may have changed... try
looking on RAA:
[ http://raa.ruby-lang.org/cat.rhtml?category_major=Library;category_minor=Graphics ]



Hope this helps,

Bill