sugar_png.rb in sugar_png-0.4.0

- old
+ new
@@ -1,5 +1,167 @@
 require 'zpng'
 
-SugarPNG = ZPNG
+require 'sugar_png/dyn_accessor'
+require 'sugar_png/color'
+require 'sugar_png/border'
+require 'sugar_png/image'
+require 'sugar_png/font'
+require 'sugar_png/glyph'
 
-require 'sugar_png/datastream'
+class SugarPNG
+  DEFAULT_BG = :transparent
+  DEFAULT_FG = :black
+
+  Canvas = Datastream = Image
+
+  class Exception < ::Exception; end
+  class ArgumentError < Exception; end
+
+  extend DynAccessor
+  dyn_accessor :width, :height, :zoom, :depth
+  dyn_accessor :bg => %w'background bg_color background_color'
+  dyn_accessor :fg => %w'foreground fg_color foreground_color color'
+
+  def initialize h={}, &block
+    @bg   = DEFAULT_BG
+    @fg   = DEFAULT_FG
+    @zoom = 1
+    clear
+
+    if block_given?
+      if block.arity == 1
+        yield self
+      else
+        instance_eval &block
+      end
+    end
+
+    # boring non-magic hash
+    h.each do |k,v|
+      self.send "#{k}=", v
+    end
+  end
+
+  # reset all drawings
+  def clear
+    @pixels  = Hash.new{ |k,v| k[v] = {} }
+    @borders = []
+  end
+
+  # set pixels
+  # accepted coordinate values:
+  # a) boring Integers
+  # b) neat   Arrays
+  # c) long   Ranges
+  # d) super  Enumerators
+  #
+  # accepted color values: see SugarPNG::Color
+  def []= ax, ay, color
+    Array(ay).each do |y|
+      Array(ax).each do |x|
+        @pixels[y][x] = color
+      end
+    end
+  end
+
+  # same as above, but color argument can be optional
+  def pixel ax, ay, color = @fg
+    Array(ay).each do |y|
+      Array(ax).each do |x|
+        @pixels[y][x] = color
+      end
+    end
+  end
+  alias :pixels :pixel
+
+  %w'put_pixel set_pixel point dot'.each do |x|
+    # plural & singular aliases to increase entropy & prevent global singularity
+    class_eval "alias :#{x} :pixel; alias :#{x}s :pixels"
+  end
+
+  # draw image border with specified color
+  def border size, color = nil
+    color ||= @fg || @bg
+    @borders << Border.new( size.is_a?(Hash) ? size : {:size => size, :color => color} )
+  end
+
+  # same as border, but default color is background
+  def padding size, color = @bg
+    border size, color
+  end
+
+  # draw a single glyph, used from within text()
+  def draw_glyph glyph, x0, y, color
+    #TODO: optimize?
+    glyph.to_a.each do |row|
+      x = x0
+      row.each do |bit|
+        self[x,y] = color if bit == 1
+        x += 1
+      end
+      y += 1
+    end
+  end
+
+  # draws text, optional arguments are :color, :x, :y
+  def text text, h = {}
+    font  = @font ||= Font.new
+    color = h[:color] || @fg
+    y = h[:y] || 0
+    text.split(/[\r\n]+/).each do |line|
+      x = h[:x] || 0
+      line.each_char do |c|
+        glyph = font[c]
+        draw_glyph glyph, x, y, color
+        x += glyph.width
+      end
+      y += font.height
+    end
+  end
+
+  # export PNG to file
+  def save fname
+    File.open(fname, "wb"){ |f| f<<to_s }
+  end
+
+  # get PNG as bytestream, for saving it to file manually, or for sending via HTTP
+  def to_s
+    height = @height || ((t=@pixels.keys.max) && t+1 ) || 0
+    width = @width || ((t=@pixels.values.map(&:keys).map(&:max).max) && t+1 ) || 0
+
+    xofs = yofs = 0
+    xmax = width-1
+    ymax = height-1
+
+    if @borders.any?
+      width  += @borders.map(&:width).inject(&:+)
+      height += @borders.map(&:height).inject(&:+)
+      xofs   += @borders.map(&:left).inject(&:+)
+      yofs   += @borders.map(&:top).inject(&:+)
+    end
+
+    raise(Exception.new("invalid image height #{height}")) if height <= 0
+    raise(Exception.new("invalid image width #{width}")) if width <= 0
+
+    img = Image.new :width => width, :height => height, :depth => @depth
+    img.clear(_color(@bg))     if @bg
+    img.draw_borders(@borders.each{ |b| b.color = _color(b.color)} )
+
+    @pixels.each do |y, xh|
+      next if y>ymax
+      xh.each do |x, c|
+        next if x>xmax
+        img[x+xofs,y+yofs] = _color(c)
+      end
+    end
+
+    img.zoom(@zoom).export
+  end
+  alias :export :to_s
+
+  private
+
+  # create color from any of the supported color representations
+  def _color c
+    c = c.is_a?(ZPNG::Color) ? c : Color.new(c, :depth => @depth)
+  end
+end