A Ruby library for games — supporting audio spatialization and 2D (and even 3D!) graphics
Ray is a library than can create windows, play music, and draw 2D graphics (or not too complex 3D by doing just a bit more work, thanks to OpenGL). It is meant to be easy and fun to use (à la Shoes), and still flexible and powerful.
See on this page. Also notice there's an IRC channel on freenode: #ray.
require 'ray'Ray.game "Hello" do register { add_hook :quit, method(:exit!) }
scene :hello do @text = text "Hello world!", :size => 30, :angle => 30, :at => [50, 50] render { |win| win.draw @text } end
scenes << :hello end
require 'ray'class TitleScene < Ray::Scene scene_name :title
def setup # setup resources end
def register # register for events end
def render(win) # draw! end
def clean_up # perform cleanup end end
class GameScene < Ray::Scene scene_name :game
same stuff
end
...
class Game < Ray::Game def initialize super "Awesome Game"
TitleScene.bind(self) GameScene.bind(self) # ... scenes << :title
end end
Ray has a drawable class that specifies a common interface to all the drawable objects – how to perform transformations to them and how to draw them.
obj = AnyDrawable.newwindow.draw obj
obj.pos = [0, 2] # set position obj.angle = 40 # rotation obj.origin = [20, 20] # just sets the origin of transformations
...
You can even have a completely custom transformation matrix:
obj.matrix = Ray::Matrix.translation [2, 3, 4]
When rendering to a window is not enough, you can render on an image just fine:
Ray::ImageTarget.new some_image do |target| target.clear Ray::Color.red target.draw Ray::Polygon.circle([50, 50], 10, Ray::Color.green) target.update end
Ray uses OpenGL, and provides some classes and methods to allow using it from Ray. In fact,
Ray::Drawablecan simply be used for OpenGL rendering:
# Ray has a more advanced sprite class, of course! class CustomSprite < Ray::Drawable def initialize(image) super() # very important: creating the actual drawable# Ray allocates a VBO to store your vertices. # You could just use your own OpenGL binding to call glBegin and glEnd # if you don't want to use it. self.vertex_count = 4 # Tells Ray to enable texturing for this drawable self.textured = true @image = image
end
return an array of vertices
def fill_vertices rect = @img.tex_rect [0, 0, @img.w, @img.h]
[ Ray::Vertex.new([0, 0], Ray::Color.white, rect.top_left), Ray::Vertex.new([@img.w, 0], Ray::Color.white, rect.top_right), Ray::Vertex.new([0, @img.h], Ray::Color.white, rect.bottom_left), Ray::Vertex.new([@img.w, @img.h], Ray::Color.white, rect.bottom_right), ]
end
The index parameter is there in case you'd want to use
draw_elements. You can fill indices by defining a fill_indices method
and setting index_count.
def render(first, index) @image.bind
# Some low level OpenGL calls are available Ray::GL.draw_arrays :triangle_strip, first, 4
end end
You can also create and use shaders from Ruby:
shader = Ray::Shader.new :vertex => "vertex_shader.glsl", :frag => "frag_shader.glsl" drawable.shader = shaderYou can't assign an image to a render target, but you can recompile it:
window.shader.compile :vertex => "vertex.glsl", :frag => "frag.glsl"
3D rendering is a very cool thing! Even if Ray's graphics module only uses 2D, a 3D API can be created with it. You can just use
Ray::Drawableagain, but you will ned to specify the layout of your vertices and to write your own shaders (the default shaders are only designed for 2D). You will probably need a custom projection matrix too.
class Cube < Ray::Drawable include Ray::GLVertex = Ray::GL::Vertex.make [ [:pos, "in_Position", :vector3], [:col, "in_Color", :color] ]
def initialize super Vertex # ... end
...
end
...
Tell the shader what vertex layout to use.
window.shader.apply_vertex Cube::Vertex window.shader.compile :vertex => "vertex.glsl", :frag => "frag.glsl"
Ray::Matrix can create 3D transformation and projection matrices!
window.view = Ray::View.new Ray::Matrix.perspective(90, 1, 1, 100)
Ray can play short sounds right away and stream longer ones — it uses OpenAL for this. 3D audio effects can be added as well.
@sound = sound "test.wav" @music = music "test.ogg"@sound.pause @music.play
@music.pause
@music.volume = 80 @music.pitch = 0.9 @music.pos = [10, 20, 30]
@music.play
Ray's events can be faked so that you can simulate user input in your tests:
require 'awesome_scene'describe AwesomeScene do before :each do @game = AwesomeGame.new @scene = @game.registered_scene(:awesome_scene)
@scene.register @scene.setup
end
it "has a cursor at (0, 0)" do @scene.cursor.pos.should == [0, 0] end
it "moves its cursor after the mouse moved" do @game.raise_event :mouse_motion, Ray::Vector2[100, 100] @game.event_runner.run
@scene.cursor.pos.should == [100, 100]
end
it "draws its cursor" do @scene.window.should_receive(:draw, @scene.cursor) @scene.render @scene.window end
after :each do @scene.clean_up end end
You can animate the fact the state of an object is changing (its position, etc.) using Ray's animation objects:
animations << translation(:from => [0, 0], :to => [100, 100], :duration => 4).start(@some_drawable)
(They can really be used to animate any change, not just those that are visible, and not just those applied to a drawable.)