Class: Rasem::SVGImage

Inherits:
Object
  • Object
show all
Defined in:
lib/rasem/svg_image.rb

Constant Summary collapse

DefaultStyle = 
{:stroke=>"black", :fill=>"black"}

Instance Method Summary collapse

Constructor Details

#initialize(width, height, output = nil, &block) ⇒ SVGImage

Returns a new instance of SVGImage.



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# File 'lib/rasem/svg_image.rb', line 4

def initialize(width, height, output=nil, &block)
  @output = create_output(output)
  
  # Initialize a stack of default styles
  @default_styles = [DefaultStyle]

  write_header(width, height)
  if block
    self.instance_exec(&block)
    self.close
  end
end

Instance Method Details

#circle(cx, cy, r, style = {}) ⇒ Object

Draw a circle given a center and a radius



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# File 'lib/rasem/svg_image.rb', line 41

def circle(cx, cy, r, style={})
  @output << %Q{<circle cx="#{cx}" cy="#{cy}" r="#{r}"}
  write_style(style)
  @output << %Q{/>}
end

#close ⇒ Object

Closes the file. No more drawing is possible after this



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# File 'lib/rasem/svg_image.rb', line 82

def close
  write_close
  @closed = true
end

#closed? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rasem/svg_image.rb', line 91

def closed?
  @closed
end

#ellipse(cx, cy, rx, ry, style = {}) ⇒ Object

Draw an circle given a center and two radii



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# File 'lib/rasem/svg_image.rb', line 67

def ellipse(cx, cy, rx, ry, style={})
  @output << %Q{<ellipse cx="#{cx}" cy="#{cy}" rx="#{rx}" ry="#{ry}"}
  write_style(style)
  @output << %Q{/>}
end

#group(style = {}, &proc) ⇒ Object 



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# File 'lib/rasem/svg_image.rb', line 106

def group(style={}, &proc)
  # Open the group
  @output << "<g"
  write_style(style)
  @output << ">"
  # Call the block
  self.instance_exec(&proc)
  # Close the group
  @output << "</g>"
end

#line(x1, y1, x2, y2, style = {}) ⇒ Object

Draw a straight line between the two end points



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# File 'lib/rasem/svg_image.rb', line 34

def line(x1, y1, x2, y2, style={})
  @output << %Q{<line x1="#{x1}" y1="#{y1}" x2="#{x2}" y2="#{y2}"}
  write_style(style)
  @output << %Q{/>}
end

#output ⇒ Object 



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# File 'lib/rasem/svg_image.rb', line 87

def output
  @output.to_s
end

#polygon(*args) ⇒ Object 



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# File 'lib/rasem/svg_image.rb', line 73

def polygon(*args)
  polything("polygon", *args)
end

#polyline(*args) ⇒ Object 



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# File 'lib/rasem/svg_image.rb', line 77

def polyline(*args)
  polything("polyline", *args)
end

#rectangle(x, y, width, height, *args) ⇒ Object

Draw a rectangle or rounded rectangle



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# File 'lib/rasem/svg_image.rb', line 48

def rectangle(x, y, width, height, *args)
  style = (!args.empty? && args.last.is_a?(Hash)) ? args.pop : {}
  if args.length == 0
    rx = ry = 0
  elsif args.length == 1
    rx = ry = args.pop
  elsif args.length == 2
    rx, ry = args
  else
    raise "Illegal number of arguments to rectangle"
  end
    
  @output << %Q{<rect x="#{x}" y="#{y}" width="#{width}" height="#{height}"}
  @output << %Q{ rx="#{rx}" ry="#{ry}"} if rx && ry
  write_style(style)
  @output << %Q{/>}
end

#set_height(new_height) ⇒ Object 



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# File 'lib/rasem/svg_image.rb', line 25

def set_height(new_height)
  if @output.respond_to?(:sub!)
    @output.sub!(/<svg width="([^"]+)" height="[^"]+"/, %Q{<svg width="\\1" height="#{new_height}"})
  else
    raise "Cannot change width after initialization for this output"
  end
end

#set_width(new_width) ⇒ Object 



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# File 'lib/rasem/svg_image.rb', line 17

def set_width(new_width)
  if @output.respond_to?(:sub!)
    @output.sub!(/<svg width="[^"]+"/, %Q{<svg width="#{new_width}"})
  else
    raise "Cannot change width after initialization for this output"
  end
end

#with_style(style = {}, &proc) ⇒ Object 



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# File 'lib/rasem/svg_image.rb', line 95

def with_style(style={}, &proc)
  # Merge passed style with current default style
  updated_style = default_style.merge(style)
  # Push updated style to the stack
  @default_styles.push(updated_style)
  # Call the block
  self.instance_exec(&proc)
  # Pop style again to revert changes
  @default_styles.pop
end