Graph with dots and labels along a vertical access see: ‘Creating More Effective Graphs’ by Robbins
| Class | Gruff::Dot |
| In: |
lib/gruff/dot.rb
|
| Parent: | Gruff::Base |
Graph with dots and labels along a vertical access see: ‘Creating More Effective Graphs’ by Robbins
# File lib/gruff/dot.rb, line 9
9: def draw
10: @has_left_labels = true
11: super
12:
13: return unless @has_data
14:
15: # Setup spacing.
16: #
17: spacing_factor = 1.0
18:
19: @items_width = @graph_height / @column_count.to_f
20: @item_width = @items_width * spacing_factor / @norm_data.size
21: @d = @d.stroke_opacity 0.0
22: height = Array.new(@column_count, 0)
23: length = Array.new(@column_count, @graph_left)
24: padding = (@items_width * (1 - spacing_factor)) / 2
25:
26: @norm_data.each_with_index do |data_row, row_index|
27: data_row[DATA_VALUES_INDEX].each_with_index do |data_point, point_index|
28:
29: x_pos = @graph_left + (data_point * @graph_width) - (@item_width.to_f/6.0).round
30: y_pos = @graph_top + (@items_width * point_index) + padding + (@item_width.to_f/2.0).round
31:
32: if row_index == 0
33: @d = @d.stroke(@marker_color)
34: @d = @d.stroke_width 1.0
35: @d = @d.opacity 0.1
36: @d = @d.line(@graph_left, y_pos, @graph_left + @graph_width, y_pos)
37: end
38:
39: @d = @d.fill data_row[DATA_COLOR_INDEX]
40: @d = @d.stroke('transparent')
41: @d = @d.circle(x_pos, y_pos, x_pos + (@item_width.to_f/3.0).round, y_pos)
42:
43: # Calculate center based on item_width and current row
44: label_center = @graph_top + (@items_width * point_index + @items_width / 2) + padding
45: draw_label(label_center, point_index)
46: end
47:
48: end
49:
50: @d.draw(@base_image)
51: end
Draw on the Y axis instead of the X
# File lib/gruff/dot.rb, line 96
96: def draw_label(y_offset, index)
97: if !@labels[index].nil? && @labels_seen[index].nil?
98: @d.fill = @font_color
99: @d.font = @font if @font
100: @d.stroke = 'transparent'
101: @d.font_weight = NormalWeight
102: @d.pointsize = scale_fontsize(@marker_font_size)
103: @d.gravity = EastGravity
104: @d = @d.annotate_scaled(@base_image,
105: 1, 1,
106: -@graph_left + LABEL_MARGIN * 2.0, y_offset,
107: @labels[index], @scale)
108: @labels_seen[index] = 1
109: end
110: end
Instead of base class version, draws vertical background lines and label
# File lib/gruff/dot.rb, line 56
56: def draw_line_markers
57:
58: return if @hide_line_markers
59:
60: @d = @d.stroke_antialias false
61:
62: # Draw horizontal line markers and annotate with numbers
63: @d = @d.stroke(@marker_color)
64: @d = @d.stroke_width 1
65: number_of_lines = 5
66:
67: # TODO Round maximum marker value to a round number like 100, 0.1, 0.5, etc.
68: increment = significant(@maximum_value.to_f / number_of_lines)
69: (0..number_of_lines).each do |index|
70:
71: line_diff = (@graph_right - @graph_left) / number_of_lines
72: x = @graph_right - (line_diff * index) - 1
73: @d = @d.line(x, @graph_bottom, x, @graph_bottom + 0.5 * LABEL_MARGIN)
74: diff = index - number_of_lines
75: marker_label = diff.abs * increment
76:
77: unless @hide_line_numbers
78: @d.fill = @font_color
79: @d.font = @font if @font
80: @d.stroke = 'transparent'
81: @d.pointsize = scale_fontsize(@marker_font_size)
82: @d.gravity = CenterGravity
83: # TODO Center text over line
84: @d = @d.annotate_scaled( @base_image,
85: 0, 0, # Width of box to draw text in
86: x, @graph_bottom + (LABEL_MARGIN * 2.0), # Coordinates of text
87: marker_label.to_s, @scale)
88: end # unless
89: @d = @d.stroke_antialias true
90: end
91: end