Class: CooCoo::Drawing::CairoCanvas

Inherits:
Canvas show all
Defined in:
lib/coo-coo/drawing/cairo_canvas.rb

Instance Attribute Summary collapse

Attributes inherited from Canvas

#fill_color, #stroke_color

Instance Method Summary collapse

Constructor Details

#initialize(surface_or_width, height = nil) ⇒ CairoCanvas

Returns a new instance of CairoCanvas.



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 9

def initialize(surface_or_width, height = nil)
  if height
    surface = Cairo::ImageSurface.new(surface_or_width, height)
  else
    surface = surface_or_width
  end
  
  @surface = surface
  @context = Cairo::Context.new(@surface)
end

Instance Attribute Details

#context ⇒ Object (readonly)

Returns the value of attribute context.



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 7

def context
  @context
end

#surface ⇒ Object (readonly)

Returns the value of attribute surface.



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 7

def surface
  @surface
end

Instance Method Details

#blit(img, x, y, w, h) ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 67

def blit(img, x, y, w, h)
  surface = Cairo::ImageSurface.from_png(StringIO.new(img))
  zx = w / surface.width.to_f
  zy = h / surface.height.to_f
  @context.set_source(surface, x / zx, y / zy)
  @context.scale(zx, zy)
  @context.paint

  self
end

#circle(x, y, r) ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 60

def circle(x, y, r)
  @context.circle(x, y, r)
  @context.set_source_rgba(*ChunkyPNG::Color.to_truecolor_alpha_bytes(fill_color))
  @context.fill
  self
end

#flush ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 20

def flush
  @surface.flush
  self
end

#line(x1, y1, x2, y2) ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 25

def line(x1, y1, x2, y2)
  @context.set_source_rgba(ChunkyPNG::Color.to_truecolor_alpha_bytes(stroke_color))
  @context.move_to(x1, y1)
  @context.line_to(x2, y2)
  @context.stroke
  self
end

#rect(x, y, w, h) ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 53

def rect(x, y, w, h)
  @context.rectangle(x, y, w, h)
  @context.set_source_rgba(*ChunkyPNG::Color.to_truecolor_alpha_bytes(fill_color))
  @context.fill
  self
end

#stroke(points) ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 33

def stroke(points)
  @context.set_source_rgba(*ChunkyPNG::Color.to_truecolor_alpha_bytes(stroke_color))
  @context.set_line_width(points[0][2])
  @context.move_to(points[0][0], points[0][1])
  @context.line_cap = Cairo::LINE_CAP_ROUND
  @context.line_join = Cairo::LINE_JOIN_ROUND

  points.each.drop(1).each do |(x, y, w, color)|
    @context.set_line_width(w)
    if color
      @context.set_source_rgba(*ChunkyPNG::Color.to_truecolor_alpha_bytes(color))
    end
    @context.line_to(x, y)
  end

  @context.stroke

  self
end

#text(txt, x, y, font, font_size, style = Cairo::FONT_SLANT_NORMAL) ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 78

def text(txt, x, y, font, font_size, style = Cairo::FONT_SLANT_NORMAL)
  @context.move_to(x, y + font_size)
  @context.set_source_rgba(*ChunkyPNG::Color.to_truecolor_alpha_bytes(fill_color))
  @context.select_font_face(font, style)
  @context.font_size = font_size
  @context.show_text(txt)
  self
end

#to_blob ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 87

def to_blob
  data = StringIO.new
  @surface.write_to_png(data)
  data.rewind
  data.read
end

#to_vector(grayscale = false) ⇒ Object 



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# File 'lib/coo-coo/drawing/cairo_canvas.rb', line 94

def to_vector(grayscale = false)
  @surface.flush
  chunky_to_vector(ChunkyPNG::Image.from_blob(to_blob), grayscale)
end