Module: Chingu::Helpers::GFX

Included in:
GameState, Window
Defined in:
lib/chingu/helpers/gfx.rb

Overview

Various helper-methods to manipulate the screen. All drawings depend on the global variable $window which should be an instance of Gosu::Window or Chingu::Window

Constant Summary collapse

CIRCLE_STEP =

Draws an unfilled circle, thanks shawn24!

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Instance Method Summary collapse

Instance Method Details

#draw_circle(cx, cy, r, color) ⇒ Object 



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# File 'lib/chingu/helpers/gfx.rb', line 80

def draw_circle(cx,cy,r,color)      
  0.step(360, CIRCLE_STEP) do |a1|
    a2 = a1 + CIRCLE_STEP
    $window.draw_line cx + Gosu.offset_x(a1, r), cy + Gosu.offset_y(a1, r), color, cx + Gosu.offset_x(a2, r), cy + Gosu.offset_y(a2, r), color, 9999
  end
end

#draw_rect(rect, color, zorder) ⇒ Object

Draws an unfilled rect in given color



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# File 'lib/chingu/helpers/gfx.rb', line 68

def draw_rect(rect, color, zorder)
  $window.draw_line(rect.x, rect.y, color, rect.right, rect.y, color, zorder)
  $window.draw_line(rect.right, rect.y, color, rect.right, rect.bottom, color, zorder)
  $window.draw_line(rect.right, rect.bottom, color, rect.x, rect.bottom, color, zorder)
  $window.draw_line(rect.x, rect.bottom, color, rect.x, rect.y, color, zorder)
end

#fill(options, zorder = 0) ⇒ Object

Fills window or a given rect with a gradient between two colors.

:from         - Start with this color
:to           - End with this color
:rect         - Only fill rectangle :rect with the gradient, either a Rect-instance or [x,y,width,height] Array.
:orientation  - Either :vertical (top to bottom) or :horizontal (left to right)



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# File 'lib/chingu/helpers/gfx.rb', line 51

def fill(options, zorder = 0)
  #
  # if only 1 color-argument is given, assume fullscreen simple color fill.
  #
  if options.is_a?(Gosu::Color)
    $window.draw_quad(0, 0, options,
                    $window.width, 0, options,
                    $window.width, $window.height, options,
                    0, $window.height, options, zorder, :default)
  else
    fill_gradient(options)
  end
end

#fill_gradient(options) ⇒ Object

Fills window or a given rect with a gradient between two colors.

:from         - Start with this color
:to           - End with this color
:rect         - Only fill rectangle :rect with the gradient, either a Rect-instance or [x,y,width,height] Array.
:orientation  - Either :vertical (top to bottom) or :horizontal (left to right)



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# File 'lib/chingu/helpers/gfx.rb', line 107

def fill_gradient(options)
  default_options = { :from => Gosu::Color::BLACK,
                      :to => Gosu::Color::WHITE,
                      :thickness => 10, 
                      :orientation => :vertical,
                      :rect => Rect.new([0, 0, $window.width, $window.height]),
                      :zorder => 0,
                      :mode => :default
                    }
  options = default_options.merge(options)
  
  rect   = Rect.new(options[:rect])
  colors = options[:colors] || options.values_at(:from, :to)
  
  case options[:orientation]
  when :vertical
    rect.height /= colors.count - 1
    colors.each_cons(2) do |from, to|
      $window.draw_quad(  rect.left,  rect.top,    from,
                          rect.right, rect.top,    from,
                          rect.right, rect.bottom, to,
                          rect.left,  rect.bottom, to,
                          options[:zorder], options[:mode]
                        )
      rect.top += rect.height
    end
  when :horizontal
    rect.width /= colors.count - 1
    colors.each_cons(2) do |from, to|
      $window.draw_quad(  rect.left,  rect.top,    from,
                          rect.left,  rect.bottom, from,
                          rect.right, rect.bottom, to,
                          rect.right, rect.top,    to,
                          options[:zorder], options[:mode]
                        )
      rect.left += rect.width
    end
  else
    raise ArgumentError, "bad gradient orientation: #{options[:orientation]}"
  end
end

#fill_rect(rect, color, zorder = 0) ⇒ Object

Fills a given Rect ‘rect’ with Color ‘color’, drawing with zorder ‘zorder’



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# File 'lib/chingu/helpers/gfx.rb', line 90

def fill_rect(rect, color, zorder = 0)
  rect = Rect.new(rect)     # Make sure it's a rect
  $window.draw_quad(  rect.x, rect.y, color,
                      rect.right, rect.y, color,
                      rect.right, rect.bottom, color,
                      rect.x, rect.bottom, color,
                      zorder, :default)
end