Class: Gruff::Base

Inherits:
Object
  • Object
show all
Includes:
Deprecated, Magick
Defined in:
lib/gruff/base.rb

Direct Known Subclasses

Area, Bar, Bullet, Line, Net, PhotoBar, Pie, Scene, SideBar, Spider, StackedArea, StackedBar

Defined Under Namespace

Modules: StackedMixin

Constant Summary collapse

DEBUG =

Draw extra lines showing where the margins and text centers are

false
DATA_LABEL_INDEX =

Used for navigating the array of data to plot

0
DATA_VALUES_INDEX = 
1
DATA_COLOR_INDEX = 
2
LEGEND_MARGIN =

Space around text elements. Mostly used for vertical spacing

TITLE_MARGIN = LABEL_MARGIN = 10.0
DEFAULT_TARGET_WIDTH = 
800

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Deprecated

#graph_height, #graph_left, #graph_top, #graph_width, #scale_measurements, #total_height

Constructor Details

#initialize(target_width = DEFAULT_TARGET_WIDTH) ⇒ Base

If one numerical argument is given, the graph is drawn at 4/3 ratio according to the given width (800 results in 800x600, 400 gives 400x300, etc.).

Or, send a geometry string for other ratios (‘800x400’, ‘400x225’).

Looks for Bitstream Vera as the default font. Expects an environment var of MAGICK_FONT_PATH to be set. (Uses RMagick’s default font otherwise.)



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# File 'lib/gruff/base.rb', line 172

def initialize(target_width=DEFAULT_TARGET_WIDTH)
  @top_margin = @bottom_margin = @left_margin = @right_margin = 20.0

  if not Numeric === target_width
    geometric_width, geometric_height = target_width.split('x')
    @columns = geometric_width.to_f
    @rows = geometric_height.to_f
  else
    @columns = target_width.to_f
    @rows = target_width.to_f * 0.75
  end

  initialize_ivars

  reset_themes
  theme_keynote
end

Instance Attribute Details

#additional_line_values ⇒ Object

Experimental



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# File 'lib/gruff/base.rb', line 153

def additional_line_values
  @additional_line_values
end

#bottom_margin ⇒ Object

Blank space below the graph



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# File 'lib/gruff/base.rb', line 47

def bottom_margin
  @bottom_margin
end

#center_labels_over_point ⇒ Object

Used internally for spacing.

By default, labels are centered over the point they represent.



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# File 'lib/gruff/base.rb', line 66

def center_labels_over_point
  @center_labels_over_point
end

#colors ⇒ Object

Get or set the list of colors that will be used to draw the bars or lines.



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# File 'lib/gruff/base.rb', line 83

def colors
  @colors
end

#font ⇒ Object

Font used for titles, labels, etc. Works best if you provide the full path to the TTF font file. RMagick must be built with the Freetype libraries for this to work properly.

Tries to find Bitstream Vera (Vera.ttf) in the location specified by ENV. Uses default RMagick font otherwise.

The font= method below fulfills the role of the writer, so we only need a reader here.



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# File 'lib/gruff/base.rb', line 97

def font
  @font
end

#font_color ⇒ Object

Returns the value of attribute font_color.



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# File 'lib/gruff/base.rb', line 99

def font_color
  @font_color
end

#has_left_labels ⇒ Object

Used internally for horizontal graph types.



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# File 'lib/gruff/base.rb', line 69

def has_left_labels
  @has_left_labels
end

#hide_legend ⇒ Object

Prevent drawing of the legend



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# File 'lib/gruff/base.rb', line 105

def hide_legend
  @hide_legend
end

#hide_line_markers ⇒ Object

Prevent drawing of line markers



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# File 'lib/gruff/base.rb', line 102

def hide_line_markers
  @hide_line_markers
end

#hide_line_numbers ⇒ Object

Prevent drawing of line numbers



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# File 'lib/gruff/base.rb', line 111

def hide_line_numbers
  @hide_line_numbers
end

#hide_title ⇒ Object

Prevent drawing of the title



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# File 'lib/gruff/base.rb', line 108

def hide_title
  @hide_title
end

#labels ⇒ Object

A hash of names for the individual columns, where the key is the array index for the column this label represents.

Not all columns need to be named.

Example: 0 => 2005, 3 => 2006, 5 => 2007, 7 => 2008



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# File 'lib/gruff/base.rb', line 61

def labels
  @labels
end

#left_margin ⇒ Object

Blank space to the left of the graph



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# File 'lib/gruff/base.rb', line 53

def left_margin
  @left_margin
end

#legend_box_size ⇒ Object

Optionally set the size of the colored box by each item in the legend. Default is 20.0

Will be scaled down if graph is smaller than 800px wide.



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# File 'lib/gruff/base.rb', line 162

def legend_box_size
  @legend_box_size
end

#legend_font_size ⇒ Object

Optionally set the size of the font. Based on an 800x600px graph. Default is 20.

Will be scaled down if graph is smaller than 800px wide.



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# File 'lib/gruff/base.rb', line 124

def legend_font_size
  @legend_font_size
end

#marker_color ⇒ Object

The color of the auxiliary lines



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# File 'lib/gruff/base.rb', line 130

def marker_color
  @marker_color
end

#marker_count ⇒ Object

The number of horizontal lines shown for reference



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# File 'lib/gruff/base.rb', line 133

def marker_count
  @marker_count
end

#marker_font_size ⇒ Object

The font size of the labels around the graph



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# File 'lib/gruff/base.rb', line 127

def marker_font_size
  @marker_font_size
end

#maximum_value ⇒ Object

You can manually set a maximum value, such as a percentage-based graph that always goes to 100.

If you use this, you must set it after you have given all your data to the graph object.



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# File 'lib/gruff/base.rb', line 146

def maximum_value
  @maximum_value
end

#minimum_value ⇒ Object

You can manually set a minimum value instead of having the values guessed for you.

Set it after you have given all your data to the graph object.



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# File 'lib/gruff/base.rb', line 139

def minimum_value
  @minimum_value
end

#no_data_message ⇒ Object

Message shown when there is no data. Fits up to 20 characters. Defaults to “No Data.”



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# File 'lib/gruff/base.rb', line 115

def no_data_message
  @no_data_message
end

#right_margin ⇒ Object

Blank space to the right of the graph



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# File 'lib/gruff/base.rb', line 50

def right_margin
  @right_margin
end

#sort ⇒ Object

Set to false if you don’t want the data to be sorted with largest avg values at the back.



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# File 'lib/gruff/base.rb', line 150

def sort
  @sort
end

#stacked ⇒ Object

Experimental



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# File 'lib/gruff/base.rb', line 156

def stacked
  @stacked
end

#title ⇒ Object

The large title of the graph displayed at the top



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# File 'lib/gruff/base.rb', line 86

def title
  @title
end

#title_font_size ⇒ Object

The font size of the large title at the top of the graph



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# File 'lib/gruff/base.rb', line 118

def title_font_size
  @title_font_size
end

#top_margin ⇒ Object

Blank space above the graph



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# File 'lib/gruff/base.rb', line 44

def top_margin
  @top_margin
end

#x_axis_label ⇒ Object

A label for the bottom of the graph



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# File 'lib/gruff/base.rb', line 72

def x_axis_label
  @x_axis_label
end

#y_axis_increment ⇒ Object

Manually set increment of the horizontal marking lines



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# File 'lib/gruff/base.rb', line 80

def y_axis_increment
  @y_axis_increment
end

#y_axis_label ⇒ Object

A label for the left side of the graph



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# File 'lib/gruff/base.rb', line 75

def y_axis_label
  @y_axis_label
end

Instance Method Details

#add_color(colorname) ⇒ Object

Add a color to the list of available colors for lines.

Example:

add_color('#c0e9d3')



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# File 'lib/gruff/base.rb', line 252

def add_color(colorname)
  @colors << colorname
end

#data(name, data_points = [], color = nil) ⇒ Object

Parameters are an array where the first element is the name of the dataset and the value is an array of values to plot.

Can be called multiple times with different datasets for a multi-valued graph.

If the color argument is nil, the next color from the default theme will be used.

NOTE: If you want to use a preset theme, you must set it before calling data().

Example:

data("Bart S.", [95, 45, 78, 89, 88, 76], '#ffcc00')



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# File 'lib/gruff/base.rb', line 436

def data(name, data_points=[], color=nil)
  data_points = Array(data_points) # make sure it's an array
  @data << [name, data_points, (color || increment_color)]
  # Set column count if this is larger than previous counts
  @column_count = (data_points.length > @column_count) ? data_points.length : @column_count

  # Pre-normalize
  data_points.each_with_index do |data_point, index|
    next if data_point.nil?

    # Setup max/min so spread starts at the low end of the data points
    if @maximum_value.nil? && @minimum_value.nil?
      @maximum_value = @minimum_value = data_point
    end

    # TODO Doesn't work with stacked bar graphs
    # Original: @maximum_value = larger_than_max?(data_point, index) ? max(data_point, index) : @maximum_value
    @maximum_value = larger_than_max?(data_point) ? data_point : @maximum_value
    @has_data = true if @maximum_value > 0

    @minimum_value = less_than_min?(data_point) ? data_point : @minimum_value
    @has_data = true if @minimum_value < 0
  end
end

#initialize_ivars ⇒ Object

Set instance variables for this object.

Subclasses can override this, call super, then set values separately.

This makes it possible to set defaults in a subclass but still allow developers to change this values in their program.



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# File 'lib/gruff/base.rb', line 196

def initialize_ivars
  # Internal for calculations
  @raw_columns = 800.0
  @raw_rows = 800.0 * (@rows/@columns)
  @column_count = 0
  @marker_count = nil
  @maximum_value = @minimum_value = nil
  @has_data = false
  @data = Array.new
  @labels = Hash.new
  @labels_seen = Hash.new
  @sort = true
  @title = nil

  @scale = @columns / @raw_columns

  vera_font_path = File.expand_path('Vera.ttf', ENV['MAGICK_FONT_PATH'])
  @font = File.exists?(vera_font_path) ? vera_font_path : nil

  @marker_font_size = 21.0
  @legend_font_size = 20.0
  @title_font_size = 36.0

  @legend_box_size = 20.0

  @no_data_message = "No Data"

  @hide_line_markers = @hide_legend = @hide_title = @hide_line_numbers = false
  @center_labels_over_point = true
  @has_left_labels = false

  @additional_line_values = []
  @additional_line_colors = []
  @theme_options = {}

  @x_axis_label = @y_axis_label = nil
  @y_axis_increment = nil
  @stacked = nil
  @norm_data = nil
end

#margins=(margin) ⇒ Object

Sets the top, bottom, left and right margins to margin.



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# File 'lib/gruff/base.rb', line 238

def margins=(margin)
  @top_margin = @left_margin = @right_margin = @bottom_margin = margin
end

#replace_colors(color_list = []) ⇒ Object

Replace the entire color list with a new array of colors. You need to have one more color than the number of datasets you intend to draw. Also aliased as the colors= setter method.

Example:

replace_colors ['#cc99cc', '#d9e043', '#34d8a2']



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# File 'lib/gruff/base.rb', line 262

def replace_colors(color_list=[])
  @colors = color_list
end

#theme=(options) ⇒ Object

You can set a theme manually. Assign a hash to this method before you send your data.

graph.theme = {
  :colors => %w(orange purple green white red),
  :marker_color => 'blue',
  :background_colors => %w(black grey)
}

:background_image => ‘squirrel.png’ is also possible.

(Or hopefully something better looking than that.)



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# File 'lib/gruff/base.rb', line 279

def theme=(options)
  reset_themes()

  defaults = {
    :colors => ['black', 'white'],
    :additional_line_colors => [],
    :marker_color => 'white',
    :font_color => 'black',
    :background_colors => nil,
    :background_image => nil
  }
  @theme_options = defaults.merge options

  @colors = @theme_options[:colors]
  @marker_color = @theme_options[:marker_color]
  @font_color = @theme_options[:font_color] || @marker_color
  @additional_line_colors = @theme_options[:additional_line_colors]

  render_background
end

#theme_37signals ⇒ Object

A color scheme plucked from the colors on the popular usability blog.



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# File 'lib/gruff/base.rb', line 321

def theme_37signals
  # Colors
  @green = '#339933'
  @purple = '#cc99cc'
  @blue = '#336699'
  @yellow = '#FFF804'
  @red = '#ff0000'
  @orange = '#cf5910'
  @black = 'black'
  @colors = [@yellow, @blue, @green, @red, @purple, @orange, @black]

  self.theme = {
    :colors => @colors,
    :marker_color => 'black',
    :font_color => 'black',
    :background_colors => ['#d1edf5', 'white']
  }
end

#theme_greyscale ⇒ Object

A greyscale theme



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# File 'lib/gruff/base.rb', line 403

def theme_greyscale
  # Colors
  @colors = [
    '#282828', #
    '#383838', #
    '#686868', #
    '#989898', #
    '#c8c8c8', #
    '#e8e8e8', #
  ]

  self.theme = {
    :colors => @colors,
    :marker_color => '#aea9a9', # Grey
    :font_color => 'black',
    :background_colors => 'white'
  }
end

#theme_keynote ⇒ Object

A color scheme similar to the popular presentation software.



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# File 'lib/gruff/base.rb', line 301

def theme_keynote
  # Colors
  @blue = '#6886B4'
  @yellow = '#FDD84E'
  @green = '#72AE6E'
  @red = '#D1695E'
  @purple = '#8A6EAF'
  @orange = '#EFAA43'
  @white = 'white'
  @colors = [@yellow, @blue, @green, @red, @purple, @orange, @white]

  self.theme = {
    :colors => @colors,
    :marker_color => 'white',
    :font_color => 'white',
    :background_colors => ['black', '#4a465a']
  }
end

#theme_odeo ⇒ Object

A color scheme similar to that used on the popular podcast site.



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# File 'lib/gruff/base.rb', line 362

def theme_odeo
  # Colors
  @grey = '#202020'
  @white = 'white'
  @dark_pink = '#a21764'
  @green = '#8ab438'
  @light_grey = '#999999'
  @dark_blue = '#3a5b87'
  @black = 'black'
  @colors = [@grey, @white, @dark_blue, @dark_pink, @green, @light_grey, @black]

  self.theme = {
    :colors => @colors,
    :marker_color => 'white',
    :font_color => 'white',
    :background_colors => ['#ff47a4', '#ff1f81']
  }
end

#theme_pastel ⇒ Object

A pastel theme



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# File 'lib/gruff/base.rb', line 382

def theme_pastel
  # Colors
  @colors = [
    '#a9dada', # blue
    '#aedaa9', # green
    '#daaea9', # peach
    '#dadaa9', # yellow
    '#a9a9da', # dk purple
    '#daaeda', # purple
    '#dadada' # grey
  ]

  self.theme = {
    :colors => @colors,
    :marker_color => '#aea9a9', # Grey
    :font_color => 'black',
    :background_colors => 'white'
  }
end

#theme_rails_keynote ⇒ Object

A color scheme from the colors used on the 2005 Rails keynote presentation at RubyConf.



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# File 'lib/gruff/base.rb', line 342

def theme_rails_keynote
  # Colors
  @green = '#00ff00'
  @grey = '#333333'
  @orange = '#ff5d00'
  @red = '#f61100'
  @white = 'white'
  @light_grey = '#999999'
  @black = 'black'
  @colors = [@green, @grey, @orange, @red, @white, @light_grey, @black]

  self.theme = {
    :colors => @colors,
    :marker_color => 'white',
    :font_color => 'white',
    :background_colors => ['#0083a3', '#0083a3']
  }
end

#to_blob(fileformat = 'PNG') ⇒ Object

Return the graph as a rendered binary blob.



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# File 'lib/gruff/base.rb', line 471

def to_blob(fileformat='PNG')
  draw()
  return @base_image.to_blob do
    self.format = fileformat
  end
end

#write(filename = "graph.png") ⇒ Object

Writes the graph to a file. Defaults to ‘graph.png’

Example:

write('graphs/my_pretty_graph.png')



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# File 'lib/gruff/base.rb', line 465

def write(filename="graph.png")
  draw()
  @base_image.write(filename)
end