Class: Squib::Graphics::CairoContextWrapper Private

Inherits:
Object
  • Object
show all
Extended by:
Forwardable
Defined in:
lib/squib/graphics/cairo_context_wrapper.rb

Overview

This class is part of a private API. You should avoid using this class if possible, as it may be removed or be changed in the future.

Wrapper class for the Cairo context. Private.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(cairo_cxt) ⇒ CairoContextWrapper

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

:nodoc:



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# File 'lib/squib/graphics/cairo_context_wrapper.rb', line 17

def initialize(cairo_cxt)
  @cairo_cxt = cairo_cxt
end

Instance Attribute Details

#cairo_cxt ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

:nodoc:



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# File 'lib/squib/graphics/cairo_context_wrapper.rb', line 13

def cairo_cxt
  @cairo_cxt
end

Instance Method Details

#fancy_stroke(draw) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Convenience method for a common task



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# File 'lib/squib/graphics/cairo_context_wrapper.rb', line 84

def fancy_stroke(draw)
  set_source_squibcolor draw.stroke_color
  set_line_width draw.stroke_width
  set_line_join draw.join
  set_line_cap draw.cap
  set_dash draw.dash
  stroke
end

#fill_n_stroke(draw) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Convenience method for a common task



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# File 'lib/squib/graphics/cairo_context_wrapper.rb', line 58

def fill_n_stroke(draw)
  return stroke_n_fill(draw) if draw.stroke_strategy == :stroke_first
  set_source_squibcolor draw.fill_color
  fill_preserve
  set_source_squibcolor draw.stroke_color
  set_line_width draw.stroke_width
  set_line_join draw.join
  set_line_cap draw.cap
  set_dash draw.dash
  stroke
end

#flip(vertical, horizontal, x, y) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Flip either vertical or horizontal depending From the cairo website: cairographics.org/matrix_transform/ cairo.Matrix(fx, 0, 0,

fy, cx*(1-fx), cy*(fy-1))

fx/fy = 1 means ‘no flip’, fx/fy = -1 are used for horizontal/vertical flip



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# File 'lib/squib/graphics/cairo_context_wrapper.rb', line 104

def flip(vertical, horizontal, x, y)
  v = vertical   ? -1.0 : 1.0
  h = horizontal ? -1.0 : 1.0
  transform Cairo::Matrix.new(v, 0.0,     0.0,
                              h, x * (1 - v), y * (1 - h))
end

#rotate_about(x, y, angle) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/squib/graphics/cairo_context_wrapper.rb', line 93

def rotate_about(x, y, angle)
  translate(x, y)
  rotate(angle)
  translate(-x, -y)
end

#set_source_squibcolor(arg) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

:nodoc:



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# File 'lib/squib/graphics/cairo_context_wrapper.rb', line 32

def set_source_squibcolor(arg)
  raise 'nil is not a valid color' if arg.nil?
  if match = arg.match(LINEAR_GRADIENT)
    x1, y1, x2, y2 = match.captures
    linear = Cairo::LinearPattern.new(x1.to_f, y1.to_f, x2.to_f, y2.to_f)
    arg.scan(STOPS).each do |color, offset|
      linear.add_color_stop(offset.to_f, color)
    end
    linear.matrix = matrix # match the coordinate systems - see bug 127
    @cairo_cxt.set_source(linear)
  elsif match = arg.match(RADIAL_GRADIENT)
    x1, y1, r1, x2, y2, r2 = match.captures
    radial = Cairo::RadialPattern.new(x1.to_f, y1.to_f, r1.to_f,
                                      x2.to_f, y2.to_f, r2.to_f)
    radial.matrix = matrix # match the coordinate systems - see bug 127
    arg.scan(STOPS).each do |color, offset|
      radial.add_color_stop(offset.to_f, color)
    end
    @cairo_cxt.set_source(radial)
  else
    @cairo_cxt.set_source_color(arg)
  end
end

#stroke_n_fill(draw) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/squib/graphics/cairo_context_wrapper.rb', line 70

def stroke_n_fill(draw)
  return fill_n_stroke(draw) if draw.stroke_strategy == :fill_first
  set_source_squibcolor draw.stroke_color
  set_line_width draw.stroke_width
  set_line_join draw.join
  set_line_cap draw.cap
  set_dash draw.dash
  stroke_preserve
  set_source_squibcolor draw.fill_color
  fill
end