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

Instance Method Summary collapse

Instance Method Details

#draw_arc(cx, cy, r, from, to, color, zorder = 0, mode = :default) ⇒ Object

Draws an unfilled arc from a1 to a2



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# File 'lib/chingu/helpers/gfx.rb', line 131

def draw_arc(cx, cy, r, from, to, color, zorder = 0, mode = :default)
  from, to = to, from if from > to
  $window.translate(cx,  cy) do
    $window.scale(r) do
      detail = _circle_segments(r)
      _walk_arc(from, to, detail) do |x1, y1, x2, y2|
        $window.draw_line(x1, y1, color,
                          x2, y2, color,
                          zorder, mode)
      end
    end
  end
end

#draw_circle(cx, cy, r, color, zorder = 0, mode = :default) ⇒ Object

Draws an unfilled circle, thanks shawn24!



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# File 'lib/chingu/helpers/gfx.rb', line 124

def draw_circle(cx, cy, r, color, zorder = 0, mode = :default)
  draw_arc(cx, cy, r, 0, 360, color, zorder, mode)
end

#draw_rect(rect, color, zorder = 0, mode = :default) ⇒ Object

Draws an unfilled rect in given color



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# File 'lib/chingu/helpers/gfx.rb', line 66

def draw_rect(rect, color, zorder = 0, mode = :default)
  rect = Rect.new(rect) unless rect.is_a? Rect
  _stroke_rect(rect, color, color, color, color, zorder, mode)
end

#fill(material, zorder = 0, mode = :default) ⇒ 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(material, zorder = 0, mode = :default)
  #
  # if only 1 color-argument is given, assume fullscreen simple color fill.
  #
  if material.is_a?(Gosu::Color)
    rect = Rect.new([0, 0, $window.width, $window.height])
    _fill_rect(rect, material, material, material, material, zorder, mode)
  else
    fill_gradient(material)
  end
end

#fill_arc(cx, cy, r, from, to, color, zorder = 0, mode = :default) ⇒ Object

Draws a filled arc from a1 to a2



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# File 'lib/chingu/helpers/gfx.rb', line 155

def fill_arc(cx, cy, r, from, to, color, zorder = 0, mode = :default)
  from, to = to, from if from > to
  $window.translate(cx,  cy) do
    $window.scale(r) do
      detail = _circle_segments(r)
      _walk_arc(from, to, detail) do |x1, y1, x2, y2|
        $window.draw_triangle(0,  0,  color,
                              x1, y1, color,
                              x2, y2, color,
                              zorder, mode)
      end
    end
  end
end

#fill_circle(cx, cy, r, color, zorder = 0, mode = :default) ⇒ Object

Draws a filled circle



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# File 'lib/chingu/helpers/gfx.rb', line 148

def fill_circle(cx, cy, r, color, zorder = 0, mode = :default)
  fill_arc(cx, cy, r, 0, 360, color, zorder, mode)
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 88

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

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

Fills a given Rect 'rect' with Color 'color', drawing with zorder 'zorder'



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# File 'lib/chingu/helpers/gfx.rb', line 75

def fill_rect(rect, color, zorder = 0, mode = :default)
  rect = Rect.new(rect) unless rect.is_a? Rect
  _fill_rect(rect, color, color, color, color, zorder, mode)
end