Module: Rabbit::Renderer::Engine::Cairo

Includes:
Kernel
Included in:
Display::ClutterEmbed, Display::DrawingArea, Display::DrawingAreaViewOnly, Offscreen, Printer, Widget::DrawingArea
Defined in:
lib/rabbit/renderer/engine/cairo.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Kernel

#draw_circle, #draw_circle_by_radius, #draw_cone, #draw_cube, #draw_dodecahedron, #draw_flag, #draw_flag_layout, #draw_icosahedron, #draw_octahedron, #draw_rectangle_flag, #draw_slide, #draw_sphere, #draw_teapot, #draw_tetrahedron, #draw_torus, #draw_triangle_flag, #flag_size, #gl_call_list, #gl_compile, #gl_supported?, #make_color, #new_list_id, #z_far, #z_view

Instance Attribute Details

#background=(value) ⇒ Object (writeonly)

Sets the attribute background

Parameters:

  • value —

    the value to set the attribute background to.



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 13

def background=(value)
  @background = value
end

#foreground=(value) ⇒ Object (writeonly)

Sets the attribute foreground

Parameters:

  • value —

    the value to set the attribute foreground to.



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 13

def foreground=(value)
  @foreground = value
end

Instance Method Details

#alpha_available? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rabbit/renderer/engine/cairo.rb', line 15

def alpha_available?
  true
end

#background_image=(pixbuf) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 19

def background_image=(pixbuf)
  surface = ::Cairo::ImageSurface.new(::Cairo::FORMAT_A1, 1, 1)
  context = ::Cairo::Context.new(surface)
  context.set_source_pixbuf(pixbuf)
  @background_image = context.source
  @background_image.extend = ::Cairo::EXTEND_REPEAT
  pixbuf
end

#create_pango_context ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 291

def create_pango_context
  context = Pango::CairoFontMap.default.create_context
  set_font_resolution(context)
  context
end

#draw_arc(filled, x, y, w, h, a1, a2, color = nil, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 141

def draw_arc(filled, x, y, w, h, a1, a2, color=nil, params={})
  r = w * 0.5
  draw_arc_by_radius(filled, x + w * 0.5, y + h * 0.5,
                     r, a1, a2, color, params)
end

#draw_arc_by_radius(filled, x, y, r, a1, a2, color = nil, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 147

def draw_arc_by_radius(filled, x, y, r, a1, a2, color=nil, params={})
  x, y = from_screen(x, y)
  a1, a2 = convert_angle(a1, a2)
  @context.save do
    set_source(color, params)
    set_line_options(params)
    args = [x, y, r, a1, a2]
    action, = cairo_action(filled, params)
    @context.move_to(x, y) unless action == :stroke
    @context.arc(*args)
    @context.close_path unless action == :stroke
    apply_cairo_action(filled, params)
  end
end

#draw_background(slide) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 93

def draw_background(slide)
  super
  if @background_image
    @context.save do
      @context.set_source(@background_image)
      @context.paint
    end
  end
end

#draw_layout(layout, x, y, color = nil, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 180

def draw_layout(layout, x, y, color=nil, params={})
  x, y = from_screen(x, y)
  @context.save do
    set_source(color, params)
    set_line_options(params)
    @context.move_to(x, y)
    if params[:stroke]
      @context.pango_layout_path(layout)
      apply_cairo_action(false, params)
    else
      @context.show_pango_layout(layout)
    end
  end
end

#draw_line(x1, y1, x2, y2, color = nil, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 103

def draw_line(x1, y1, x2, y2, color=nil, params={})
  x1, y1 = from_screen(x1, y1)
  x2, y2 = from_screen(x2, y2)
  @context.save do
    set_source(color, params)
    set_line_options(params)
    @context.new_path
    @context.move_to(x1, y1)
    @context.line_to(x2, y2)
    apply_cairo_action(false, params)
  end
end

#draw_lines(points, color = nil, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 162

def draw_lines(points, color=nil, params={})
  draw_polygon(false, points, color, params.merge({:opened => true}))
end

#draw_link(uri) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 271

def draw_link(uri)
  if @context.respond_to?(:tag)
    @context.tag(::Cairo::Tag::LINK, "uri='#{uri}'") do
      yield
    end
  else
    yield
  end
end

#draw_pixbuf(pixbuf, x, y, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 195

def draw_pixbuf(pixbuf, x, y, params={})
  x, y = from_screen(x, y)
  @context.save do
    @context.translate(x, y)
    set_source_pixbuf(pixbuf, params)
    @context.paint(params[:alpha])
  end

  _draw_reflected_pixbuf(pixbuf, x, y, params)
end

#draw_polygon(filled, points, color = nil, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 166

def draw_polygon(filled, points, color=nil, params={})
  return if points.empty?
  @context.save do
    set_source(color, params)
    set_line_options(params)
    @context.move_to(*from_screen(*points.first))
    points[1..-1].each do |x, y|
      @context.line_to(*from_screen(x, y))
    end
    @context.line_to(*from_screen(*points.first)) unless params[:opened]
    apply_cairo_action(filled, params)
  end
end

#draw_poppler_page(page, x, y, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 259

def draw_poppler_page(page, x, y, params={})
  x, y = from_screen(x, y)
  w, h = page.size
  width = (params[:width] || w).to_f
  height = (params[:height] || h).to_f
  @context.save do
    @context.translate(x, y)
    @context.scale(width / w, height / h)
    @context.render_poppler_page(page)
  end
end

#draw_rectangle(filled, x, y, w, h, color = nil, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 116

def draw_rectangle(filled, x, y, w, h, color=nil, params={})
  x, y = from_screen(x, y)
  @context.save do
    set_source(color, params)
    set_line_options(params)
    @context.rectangle(x, y, w, h)
    apply_cairo_action(filled, params)
  end
end

#draw_rounded_rectangle(filled, x, y, w, h, radius, color = nil, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 126

def draw_rounded_rectangle(filled, x, y, w, h, radius,
                           color=nil, params={})
  x, y = from_screen(x, y)
  x_radius = params[:x_radius] || radius
  y_radius = params[:y_radius] || radius

  @context.save do
    set_source(color, params)
    set_line_options(params)
    @context.new_path
    @context.rounded_rectangle(x, y, w, h, x_radius, y_radius)
    apply_cairo_action(filled, params)
  end
end

#draw_rsvg_handle(handle, x, y, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 244

def draw_rsvg_handle(handle, x, y, params={})
  x, y = from_screen(x, y)
  dim = handle.dimensions
  width = (params[:width] || dim.width).to_f
  height = (params[:height] || dim.height).to_f
  @context.save do
    @context.translate(x, y)
    @context.scale(width / dim.width, height / dim.height)
    @context.render_rsvg_handle(handle)
  end

  _draw_reflected_rsvg_handle(handle, x, y, width, height,
                              params)
end

#finish_context ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 45

def finish_context
  @contexts.pop
  @context.destroy if @context.respond_to?(:destroy)
  @context = @contexts.last
end

#finish_renderer ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 32

def finish_renderer
  finish_context
end

#init_context(context) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 36

def init_context(context)
  @context = context
  @contexts ||= []
  @contexts.push(@context)
  set_line_width(1)
  @context.line_cap = ::Cairo::LINE_CAP_ROUND
  @context.line_join = ::Cairo::LINE_JOIN_ROUND
end

#init_renderer(drawable) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 28

def init_renderer(drawable)
  init_context(drawable.create_cairo_context)
end

#make_layout(text) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 281

def make_layout(text)
  attributes, text = Pango.parse_markup(text)
  layout = @context.create_pango_layout
  layout.text = text
  layout.attributes = attributes
  set_font_resolution(layout.context)
  @context.update_pango_layout(layout)
  layout
end

#reflect_context(base, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 67

def reflect_context(base, params={})
  case base
  when :y
    matrix = make_matrix(-1, 0, 0,
                          0, 1, 0)
  else
    matrix = make_matrix(1,  0, 0,
                         0, -1, 0)
  end
  @context.transform(matrix)
end

#restore_context ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 89

def restore_context
  @context.restore
end

#rotate_context(angle, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 59

def rotate_context(angle, params={})
  @context.rotate(convert_angle(angle, 0)[0])
end

#save_context ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 84

def save_context
  @context.save
  super
end

#scale_context(x, y, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 63

def scale_context(x, y, params={})
  @context.scale(x, y)
end

#set_font_resolution(context) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 297

def set_font_resolution(context)
  context.resolution = @canvas.font_resolution
end

#set_source_pixbuf(pixbuf, params) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 206

def set_source_pixbuf(pixbuf, params)
  draw_scaled_pixbuf = params[:draw_scaled_pixbuf]
  draw_scaled_pixbuf = @draw_scaled_image if draw_scaled_pixbuf.nil?
  width = (params[:width] || pixbuf.width).to_f
  height = (params[:height] || pixbuf.height).to_f

  if [width, height] == [pixbuf.width, pixbuf.height]
    @context.set_source_pixbuf(pixbuf, 0, 0)
    return
  end

  case draw_scaled_pixbuf
  when true
    scaled_pixbuf = pixbuf.scale(width, height)
    @context.set_source_pixbuf(scaled_pixbuf, 0, 0)
  when false
    @context.set_source_pixbuf(pixbuf, 0, 0)
    matrix = ::Cairo::Matrix.scale(pixbuf.width / width,
                                   pixbuf.height / height)
    @context.source.matrix = matrix
  else
    scales = [4, 3, 2]
    scales.each do |scale|
      if width * scale < pixbuf.width and height * scale < pixbuf.height
        scaled_pixbuf = pixbuf.scale(width * scale, height * scale)
        @context.set_source_pixbuf(scaled_pixbuf)
        matrix = ::Cairo::Matrix.scale(scale, scale)
        @context.source.matrix = matrix
        return
      end
    end
    @context.set_source_pixbuf(pixbuf, 0, 0)
    matrix = ::Cairo::Matrix.scale(pixbuf.width / width,
                                   pixbuf.height / height)
    @context.source.matrix = matrix
  end
end

#shear_context(x, y, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 79

def shear_context(x, y, params={})
  @context.transform(make_matrix(1, x, 0,
                                 y, 1, 0))
end

#to_gdk_rgb(color) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 51

def to_gdk_rgb(color)
  make_color(color).to_gdk_rgb
end

#translate_context(x, y, params = {}) ⇒ Object 



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# File 'lib/rabbit/renderer/engine/cairo.rb', line 55

def translate_context(x, y, params={})
  @context.translate(x, y)
end