Module: Rubygame::Sprites::MovingSprite

Defined in:
lib/xgame.rb

Overview

This is a mixin module for sprites that move

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(base) ⇒ Object 



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# File 'lib/xgame.rb', line 127

def self.included(base)
	base.class_eval {alias_method :update_no_moving, :update; alias_method :update, :update_moving}
end

Instance Method Details

#apply_force(value) ⇒ Object

Apply a force to this sprite [vx, vy, max_applied (optional)]



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# File 'lib/xgame.rb', line 120

def apply_force(value)
	@velocity[:left] += value[0]*-1 if value[0] < 0 and (!value[2][:left] or @velocity[:left] < value[2][:left])
	@velocity[:right] += value[0] if value[0] > 0 and (!value[2][:right] or @velocity[:right] < value[2][:right])
	@velocity[:up] += value[1]*-1 if value[1] < 0 and (!value[2][:up] or @velocity[:up] < value[2][:up])
	@velocity[:down] += value[1] if value[1] > 0 and (!value[2][:down] or @velocity[:down] < value[2][:down])
end

#go(v, duration = 0) ⇒ Object

Go in some direction [vx, vy]. If either is nil, motion on that axis will not be affected.



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# File 'lib/xgame.rb', line 80

def go(v, duration=0)
	if v[0]
		if v[0] <= 0
			@animating[:left] = [duration, @velocity[:left]]
			@velocity[:left] = v[0]*-1
			@going[:left] = true
		end
		if v[0] >= 0
			@animating[:right] = [duration, @velocity[:right]]
			@velocity[:right] = v[0]
			@going[:right] = true
		end
	end
	if v[1]
		if v[1] <= 0
			@animating[:up] = [duration, @velocity[:up]]
			@velocity[:up] = v[1]*-1
			@going[:up] = true
		end
		if v[1] >= 0
			@animating[:down] = [duration, @velocity[:down]]
			@velocity[:down] = v[1]
			@going[:down] = true
		end
	end
end

#going ⇒ Object 



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# File 'lib/xgame.rb', line 71

def going
	@going
end

#hit(v, by = nil) ⇒ Object

Strike the sprite in a certain direction



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# File 'lib/xgame.rb', line 115

def hit(v, by=nil)
	self.go(v,[2,(1/(XGame.framerate/1000.0))/(@speed/4)].max)
end

#initialize(*args) ⇒ Object 



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# File 'lib/xgame.rb', line 58

def initialize(*args)
	super
	@velocity = {:left => 0, :right => 0, :up => 0, :down => 0} # These are the initial components of velocity
	@going = {:left => false, :right => false, :up => false, :down => false} # Are we "going" in these directions or just travelling?
	@reference = [0,0] # Moving frame of reference
	@animating = {:left => [0,0], :right => [0,0], :up => [0,0], :down => [0,0]}
	@speed = 50 # This can be overidden by implementations: it is how fast / massive the sprite is
end

#reference=(v) ⇒ Object 



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# File 'lib/xgame.rb', line 75

def reference=(v)
	@reference = v
end

#stop(direction, duration = 0) ⇒ Object

Stop some component of motion



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# File 'lib/xgame.rb', line 108

def stop(direction, duration=0)
	@animating[direction] = [duration, @animating[direction][0] >= 1 ? @animating[direction][1] : @velocity[direction]]
	@velocity[direction] = 0
	@going[direction] = false
end

#update_moving(time) ⇒ Object 



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# File 'lib/xgame.rb', line 131

def update_moving(time)
	update_no_moving(time)

	if @animating[:left][0] > 0
		@animating[:left][0] -= 1
		@velocity[:left] = @animating[:left][1] if @animating[:left][0] < 1
	end
	if @animating[:right][0] > 0
		@animating[:right][0] -= 1
		@velocity[:right] = @animating[:right][1] if @animating[:right][0] < 1
	end
	if @animating[:up][0] > 0
		@animating[:up][0] -= 1
		@velocity[:up] = @animating[:up][1] if @animating[:up][0]  < 1
	end
	if @animating[:down][0] > 0
		@animating[:down][0] -= 1
		@velocity[:down] = @animating[:down][1] if @animating[:down][0] < 1
	end
	x,y = @rect.center
	base = @speed * time/1000.0

	@rect.centerx = x + (@reference[0] + velocity[0]) * base
	@rect.centery = y + (@reference[1] + velocity[1]) * base
	@reference = [0,0] # Frame of reference must be reset every frame
end

#velocity ⇒ Object 



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# File 'lib/xgame.rb', line 67

def velocity
	[@velocity[:left]*-1 + @velocity[:right], @velocity[:up]*-1 + @velocity[:down]]
end