Object
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.)
# File lib/gruff/base.rb, line 180 def initialize(target_width=DEFAULT_TARGET_WIDTH) 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
Add a color to the list of available colors for lines.
Example:
add_color('#c0e9d3')
# File lib/gruff/base.rb, line 262 def add_color(colorname) @colors << colorname end
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')
# File lib/gruff/base.rb, line 455 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
Sets the font for graph text to the font at font_path.
# File lib/gruff/base.rb, line 253 def font=(font_path) @font = font_path @d.font = @font end
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.
# File lib/gruff/base.rb, line 202 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 @top_margin = @bottom_margin = @left_margin = @right_margin = DEFAULT_MARGIN @legend_margin = LEGEND_MARGIN @title_margin = TITLE_MARGIN @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
Sets the top, bottom, left and right margins to margin.
# File lib/gruff/base.rb, line 248 def margins=(margin) @top_margin = @left_margin = @right_margin = @bottom_margin = margin end
Replace the entire color list with a new array of colors. Also aliased as the colors= setter method.
If you specify fewer colors than the number of datasets you intend to draw, 'increment_color' will cycle through the array, reusing colors as needed.
Note that (as with the 'theme' method), you should set up your color list before you send your data (via the 'data' method). Calls to the 'data' method made prior to this call will use whatever color scheme was in place at the time data was called.
Example:
replace_colors ['#cc99cc', '#d9e043', '#34d8a2']
# File lib/gruff/base.rb, line 280 def replace_colors(color_list=[]) @colors = color_list @color_index = 0 end
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.)
# File lib/gruff/base.rb, line 298 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
A color scheme plucked from the colors on the popular usability blog.
# File lib/gruff/base.rb, line 340 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
A greyscale theme
# File lib/gruff/base.rb, line 422 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
A color scheme similar to the popular presentation software.
# File lib/gruff/base.rb, line 320 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
A color scheme similar to that used on the popular podcast site.
# File lib/gruff/base.rb, line 381 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
A pastel theme
# File lib/gruff/base.rb, line 401 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
A color scheme from the colors used on the 2005 Rails keynote presentation at RubyConf.
# File lib/gruff/base.rb, line 361 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
Return a calculation of center
# File lib/gruff/base.rb, line 755 def center(size) (@raw_columns - size) / 2 end
Overridden by subclasses to do the actual plotting of the graph.
Subclasses should start by calling super() for this method.
# File lib/gruff/base.rb, line 504 def draw make_stacked if @stacked setup_drawing debug { # Outer margin @d.rectangle( @left_margin, @top_margin, @raw_columns - @right_margin, @raw_rows - @bottom_margin) # Graph area box @d.rectangle( @graph_left, @graph_top, @graph_right, @graph_bottom) } end
Draw the optional labels for the x axis and y axis.
# File lib/gruff/base.rb, line 628 def draw_axis_labels unless @x_axis_label.nil? # X Axis # Centered vertically and horizontally by setting the # height to 1.0 and the width to the width of the graph. x_axis_label_y_coordinate = @graph_bottom + LABEL_MARGIN * 2 + @marker_caps_height # TODO Center between graph area @d.fill = @font_color @d.font = @font if @font @d.stroke('transparent') @d.pointsize = scale_fontsize(@marker_font_size) @d.gravity = NorthGravity @d = @d.annotate_scaled( @base_image, @raw_columns, 1.0, 0.0, x_axis_label_y_coordinate, @x_axis_label, @scale) debug { @d.line 0.0, x_axis_label_y_coordinate, @raw_columns, x_axis_label_y_coordinate } end unless @y_axis_label.nil? # Y Axis, rotated vertically @d.rotation = 90.0 @d.gravity = CenterGravity @d = @d.annotate_scaled( @base_image, 1.0, @raw_rows, @left_margin + @marker_caps_height / 2.0, 0.0, @y_axis_label, @scale) @d.rotation = -90.0 end end
Draws column labels below graph, centered over x_offset
# File lib/gruff/base.rb, line 856 def draw_label(x_offset, index) return if @hide_line_markers if !@labels[index].nil? && @labels_seen[index].nil? y_offset = @graph_bottom + LABEL_MARGIN @d.fill = @font_color @d.font = @font if @font @d.stroke('transparent') @d.font_weight = NormalWeight @d.pointsize = scale_fontsize(@marker_font_size) @d.gravity = NorthGravity @d = @d.annotate_scaled(@base_image, 1.0, 1.0, x_offset, y_offset, @labels[index], @scale) @labels_seen[index] = 1 debug { @d.line 0.0, y_offset, @raw_columns, y_offset } end end
Draws a legend with the names of the datasets matched to the colors used to draw them.
# File lib/gruff/base.rb, line 763 def draw_legend return if @hide_legend @legend_labels = @data.collect {|item| item[DATA_LABEL_INDEX] } legend_square_width = @legend_box_size # small square with color of this item # May fix legend drawing problem at small sizes @d.font = @font if @font @d.pointsize = @legend_font_size label_widths = [[]] # Used to calculate line wrap @legend_labels.each do |label| metrics = @d.get_type_metrics(@base_image, label.to_s) label_width = metrics.width + legend_square_width * 2.7 label_widths.last.push label_width if sum(label_widths.last) > (@raw_columns * 0.9) label_widths.push [label_widths.last.pop] end end current_x_offset = center(sum(label_widths.first)) current_y_offset = @hide_title ? @top_margin + title_margin : @top_margin + title_margin + @title_caps_height @legend_labels.each_with_index do |legend_label, index| # Draw label @d.fill = @font_color @d.font = @font if @font @d.pointsize = scale_fontsize(@legend_font_size) @d.stroke('transparent') @d.font_weight = NormalWeight @d.gravity = WestGravity @d = @d.annotate_scaled( @base_image, @raw_columns, 1.0, current_x_offset + (legend_square_width * 1.7), current_y_offset, legend_label.to_s, @scale) # Now draw box with color of this dataset @d = @d.stroke('transparent') @d = @d.fill @data[index][DATA_COLOR_INDEX] @d = @d.rectangle(current_x_offset, current_y_offset - legend_square_width / 2.0, current_x_offset + legend_square_width, current_y_offset + legend_square_width / 2.0) @d.pointsize = @legend_font_size metrics = @d.get_type_metrics(@base_image, legend_label.to_s) current_string_offset = metrics.width + (legend_square_width * 2.7) # Handle wrapping label_widths.first.shift if label_widths.first.empty? debug { @d.line 0.0, current_y_offset, @raw_columns, current_y_offset } label_widths.shift current_x_offset = center(sum(label_widths.first)) unless label_widths.empty? line_height = [@legend_caps_height, legend_square_width].max + legend_margin if label_widths.length > 0 # Wrap to next line and shrink available graph dimensions current_y_offset += line_height @graph_top += line_height @graph_height = @graph_bottom - @graph_top end else current_x_offset += current_string_offset end end @color_index = 0 end
Draws horizontal background lines and labels
# File lib/gruff/base.rb, line 661 def draw_line_markers return if @hide_line_markers @d = @d.stroke_antialias false if @y_axis_increment.nil? # Try to use a number of horizontal lines that will come out even. # # TODO Do the same for larger numbers...100, 75, 50, 25 if @marker_count.nil? (3..7).each do |lines| if @spread % lines == 0.0 @marker_count = lines break end end @marker_count ||= 4 end @increment = (@spread > 0) ? significant(@spread / @marker_count) : 1 else # TODO Make this work for negative values @maximum_value = [@maximum_value.ceil, @y_axis_increment].max @minimum_value = @minimum_value.floor calculate_spread normalize(true) @marker_count = (@spread / @y_axis_increment).to_i @increment = @y_axis_increment end @increment_scaled = @graph_height.to_f / (@spread / @increment) # Draw horizontal line markers and annotate with numbers (0..@marker_count).each do |index| y = @graph_top + @graph_height - index.to_f * @increment_scaled @d = @d.fill(@marker_color) @d = @d.line(@graph_left, y, @graph_right, y) marker_label = BigDecimal(index.to_s) * BigDecimal(@increment.to_s) + BigDecimal(@minimum_value.to_s) unless @hide_line_numbers @d.fill = @font_color @d.font = @font if @font @d.stroke('transparent') @d.pointsize = scale_fontsize(@marker_font_size) @d.gravity = EastGravity # Vertically center with 1.0 for the height @d = @d.annotate_scaled( @base_image, @graph_left - LABEL_MARGIN, 1.0, 0.0, y, label(marker_label), @scale) end end # # Submitted by a contibutor...the utility escapes me # i = 0 # @additional_line_values.each do |value| # @increment_scaled = @graph_height.to_f / (@maximum_value.to_f / value) # # y = @graph_top + @graph_height - @increment_scaled # # @d = @d.stroke(@additional_line_colors[i]) # @d = @d.line(@graph_left, y, @graph_right, y) # # # @d.fill = @additional_line_colors[i] # @d.font = @font if @font # @d.stroke('transparent') # @d.pointsize = scale_fontsize(@marker_font_size) # @d.gravity = EastGravity # @d = @d.annotate_scaled( @base_image, # 100, 20, # -10, y - (@marker_font_size/2.0), # "", @scale) # i += 1 # end @d = @d.stroke_antialias true end
Shows an error message because you have no data.
# File lib/gruff/base.rb, line 878 def draw_no_data @d.fill = @font_color @d.font = @font if @font @d.stroke('transparent') @d.font_weight = NormalWeight @d.pointsize = scale_fontsize(80) @d.gravity = CenterGravity @d = @d.annotate_scaled( @base_image, @raw_columns, @raw_rows/2.0, 0, 10, @no_data_message, @scale) end
Draws a title on the graph.
# File lib/gruff/base.rb, line 838 def draw_title return if (@hide_title || @title.nil?) @d.fill = @font_color @d.font = @font if @font @d.stroke('transparent') @d.pointsize = scale_fontsize(@title_font_size) @d.font_weight = BoldWeight @d.gravity = NorthGravity @d = @d.annotate_scaled( @base_image, @raw_columns, 1.0, 0, @top_margin, @title, @scale) end
Used by StackedBar and child classes.
May need to be moved to the StackedBar class.
# File lib/gruff/base.rb, line 1016 def get_maximum_by_stack # Get sum of each stack max_hash = {} @data.each do |data_set| data_set[DATA_VALUES_INDEX].each_with_index do |data_point, i| max_hash[i] = 0.0 unless max_hash[i] max_hash[i] += data_point.to_f end end # @maximum_value = 0 max_hash.keys.each do |key| @maximum_value = max_hash[key] if max_hash[key] > @maximum_value end @minimum_value = 0 end
Make copy of data with values scaled between 0-100
# File lib/gruff/base.rb, line 540 def normalize(force=false) if @norm_data.nil? || force @norm_data = [] return unless @has_data calculate_spread @data.each do |data_row| norm_data_points = [] data_row[DATA_VALUES_INDEX].each do |data_point| if data_point.nil? norm_data_points << nil else norm_data_points << ((data_point.to_f - @minimum_value.to_f ) / @spread) end end @norm_data << [data_row[DATA_LABEL_INDEX], norm_data_points, data_row[DATA_COLOR_INDEX]] end end end
Finds the best background to render based on the provided theme options.
Creates a @base_image to draw on.
# File lib/gruff/base.rb, line 894 def render_background case @theme_options[:background_colors] when Array @base_image = render_gradiated_background(*@theme_options[:background_colors]) when String @base_image = render_solid_background(@theme_options[:background_colors]) else @base_image = render_image_background(*@theme_options[:background_image]) end end
Use with a theme definition method to draw a gradiated background.
# File lib/gruff/base.rb, line 913 def render_gradiated_background(top_color, bottom_color) Image.new(@columns, @rows, GradientFill.new(0, 0, 100, 0, top_color, bottom_color)) end
Use with a theme to use an image (800x600 original) background.
# File lib/gruff/base.rb, line 919 def render_image_background(image_path) image = Image.read(image_path) if @scale != 1.0 image[0].resize!(@scale) # TODO Resize with new scale (crop if necessary for wide graph) end image[0] end
Make a new image at the current size with a solid color.
# File lib/gruff/base.rb, line 906 def render_solid_background(color) Image.new(@columns, @rows) { self.background_color = color } end
Use with a theme to make a transparent background
# File lib/gruff/base.rb, line 928 def render_transparent_background Image.new(@columns, @rows) do self.background_color = 'transparent' end end
Resets everything to defaults (except data).
# File lib/gruff/base.rb, line 935 def reset_themes @color_index = 0 @labels_seen = {} @theme_options = {} @d = Draw.new # Scale down from 800x600 used to calculate drawing. @d = @d.scale(@scale, @scale) end
Return a comparable fontsize for the current graph.
# File lib/gruff/base.rb, line 950 def scale_fontsize(value) new_fontsize = value * @scale # return new_fontsize < 10.0 ? 10.0 : new_fontsize return new_fontsize end
Calculates size of drawable area and draws the decorations.
line markers
legend
title
# File lib/gruff/base.rb, line 522 def setup_drawing # Maybe should be done in one of the following functions for more granularity. unless @has_data draw_no_data() return end normalize() setup_graph_measurements() sort_norm_data() if @sort # Sort norm_data with avg largest values set first (for display) draw_legend() draw_line_markers() draw_axis_labels() draw_title end
Calculates size of drawable area, general font dimensions, etc.
# File lib/gruff/base.rb, line 569 def setup_graph_measurements @marker_caps_height = @hide_line_markers ? 0 : calculate_caps_height(@marker_font_size) @title_caps_height = @hide_title ? 0 : calculate_caps_height(@title_font_size) @legend_caps_height = @hide_legend ? 0 : calculate_caps_height(@legend_font_size) if @hide_line_markers (@graph_left, @graph_right_margin, @graph_bottom_margin) = [@left_margin, @right_margin, @bottom_margin] else longest_left_label_width = 0 if @has_left_labels longest_left_label_width = calculate_width(@marker_font_size, labels.values.inject('') { |value, memo| (value.to_s.length > memo.to_s.length) ? value : memo }) * 1.25 else longest_left_label_width = calculate_width(@marker_font_size, label(@maximum_value.to_f)) end # Shift graph if left line numbers are hidden line_number_width = @hide_line_numbers && !@has_left_labels ? 0.0 : (longest_left_label_width + LABEL_MARGIN * 2) @graph_left = @left_margin + line_number_width + (@y_axis_label.nil? ? 0.0 : @marker_caps_height + LABEL_MARGIN * 2) # Make space for half the width of the rightmost column label. # Might be greater than the number of columns if between-style bar markers are used. last_label = @labels.keys.sort.last.to_i extra_room_for_long_label = (last_label >= (@column_count-1) && @center_labels_over_point) ? calculate_width(@marker_font_size, @labels[last_label]) / 2.0 : 0 @graph_right_margin = @right_margin + extra_room_for_long_label @graph_bottom_margin = @bottom_margin + @marker_caps_height + LABEL_MARGIN end @graph_right = @raw_columns - @graph_right_margin @graph_width = @raw_columns - @graph_left - @graph_right_margin # When @hide title, leave a title_margin space for aesthetics. # Same with @hide_legend @graph_top = @top_margin + (@hide_title ? title_margin : @title_caps_height + title_margin ) + (@hide_legend ? legend_margin : @legend_caps_height + legend_margin) x_axis_label_height = @x_axis_label.nil? ? 0.0 : @marker_caps_height + LABEL_MARGIN @graph_bottom = @raw_rows - @graph_bottom_margin - x_axis_label_height @graph_height = @graph_bottom - @graph_top end
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