+++ /dev/null
-# This file is part of NIT ( http://www.nitlanguage.org ).
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-# Framework for 2D management of game elements
-#
-# TODO: collision framework (with quad tree?)
-module scene2d
-
-# The root class of the living objects (sprites, group of sprites, etc.)
-abstract class LiveObject
- # Compute the position, state and appearance.
- fun update do end
-
- # Controls whether `update' and `draw' are automatically called by `LiveGroup'
- var exists = true is writable
-
- # Redefine this method to asks how to draw on a view
- fun draw(view: View) is abstract
-end
-
-
-# The basic atomic living and moving object.
-#
-# A sprite has a position and a velocity
-class Sprite
- super LiveObject
-
- # x coordinate of the center point
- var x: Int = 0 is writable
-
- # y coordinate of the center point
- var y: Int = 0 is writable
-
- # width of the sprite
- var width: Int = 100 is writable
-
- # height of the sprite
- var height: Int = 100 is writable
-
- # X coordinate of left side.
- fun left: Int do return x - width/2
-
- # X coordinate of right side.
- fun right: Int do return x + width/2
-
- # Y coordinate of top.
- fun top: Int do return y - height/2
-
- # Y coordinate of bottom.
- fun bottom: Int do return y + height/2
-
- # x velocity (applied by `update')
- var vx: Int = 0 is writable
-
- # y velocity (applied by `update')
- var vy: Int = 0 is writable
-
- redef fun update
- do
- self.x += self.vx
- self.y += self.vy
- end
-
- redef fun draw(view) do view.draw_sprite(self)
-
- # Is self overlaps (or contains) an other sprite
- # `x', `y', `width', and `height' of both sprites are considered
- fun overlaps(other: Sprite): Bool
- do
- return self.right > other.left and self.left < other.right and self.bottom > other.top and self.top < other.bottom
- end
-
- # Return the current angle of velocity
- # Often used to rotate the displayed image with the correct angle
- fun velocity_angle: Float
- do
- return atan2(self.vx.to_f, -self.vy.to_f)
- end
-
- # Return the angle to target an other sprite
- fun angle_to(target: Sprite): Float
- do
- return atan2((target.x-self.x).to_f, (self.y-target.y).to_f)
- end
-
- # Update of vx and vy toward a given angle and magnitude
- fun set_velocity(angle: Float, maginude: Int)
- do
- var magf = maginude.to_f
- self.vx = (angle.sin * magf).to_i
- self.vy = (angle.cos * -magf).to_i
- end
-
-end
-
-# Organizational class to manage groups of sprites and other live objects.
-class LiveGroup[E: LiveObject]
- super LiveObject
- super List[E]
-
- # Recursively update each live objects that `exists'
- redef fun update
- do
- for x in self do if x.exists then x.update
- end
-
- # Remove all live Objects that do not exists
- # Call this to cleanup the live group
- fun gc
- do
- var i = self.iterator
- while i.is_ok do
- var e = i.item
- if not e.exists then
- i.delete
- else if e isa LiveGroup[LiveObject] then
- e.gc
- end
- i.next
- end
- end
-
- # Recursively draw each live objects that `exists'
- redef fun draw(view)
- do
- for x in self do if x.exists then x.draw(view)
- end
-end
-
-# A state in the game logic
-# A scene manage a bunch of live objects
-class Scene
- super LiveObject
-end
-
-# Abstract view do draw sprites
-#
-# Concrete views are specific for each back-end.
-# View can also be used to implements camera and other fun things.
-interface View
- # Draw a specific sprite on the view
- #
- # This method must be implemented for each specific view.
- # A traditional way of implementation is to use a double-dispatch mechanism
- #
- # class MyView
- # super View
- # redef fun draw_sprite(s) do s.draw_on_myview(self)
- # end
- # redef class Sprite
- # # How to draw a sprite on my specific view
- # fun draw_on_myview(myview: MyView) is abstract
- # end
- fun draw_sprite(s: Sprite) is abstract
-end
nitlanguage / nit.git / blobdiff