Class: SvgConform::Requirements::TextAsPathRequirement

Inherits:
BaseRequirement
  • Object
show all
Defined in:
lib/svg_conform/requirements/text_as_path_requirement.rb

Overview

Detects SVG files where text is rendered as outlined path glyphs instead of native elements.

An SVG is flagged when ALL of these conditions are met:

1. No <text> element present
2. No <image> element present
3. Contains bezier curves (C/c/Q/q commands) in path d attributes
4. Longest single path d string >= min_d_length

These files are problematic because:

- Text cannot be indexed or copied
- Glyph outlines are much larger than text elements
- Poorly rendered in many graphics viewers

This is a quality check (severity: warning), not a schema violation. There is no remediation since outlined text cannot be auto-converted.

Defined Under Namespace

Classes: State

Instance Method Summary collapse

Methods inherited from BaseRequirement

#check, #get_attributes, #should_check_node?, #skip_attribute_validation?, #to_s, #validate_sax_element

Methods included from Interfaces::RequirementInterface

#check, #reset_state, #should_check_node?, #to_s, #validate_sax_element

Methods included from NodeHelpers

#element?, #get_attribute, #has_attribute?, #remove_attribute, #set_attribute, #text?

Instance Method Details

#collect_sax_data(element, context) ⇒ Object 



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# File 'lib/svg_conform/requirements/text_as_path_requirement.rb', line 59

def collect_sax_data(element, context)
  state = context.state_for(self)

  case element.name
  when "text"
    state.has_text_element = true
  when "image"
    state.has_image_element = true
  when "path"
    d_value = element["d"]
    state.path_ds << d_value if d_value && !d_value.empty?
  end
end

#needs_deferred_validation? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/svg_conform/requirements/text_as_path_requirement.rb', line 47

def needs_deferred_validation?
  true
end

#validate_document(document, context) ⇒ Object

Override validate_document to do nothing since this requirement only supports SAX-based deferred validation. DOM validation is not supported because we need to collect all path data before making a determination.



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# File 'lib/svg_conform/requirements/text_as_path_requirement.rb', line 55

def validate_document(document, context)
  # No-op: This requirement only works with SAX deferred validation
end

#validate_sax_complete(context) ⇒ Object 



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# File 'lib/svg_conform/requirements/text_as_path_requirement.rb', line 73

def validate_sax_complete(context)
  state = context.state_for(self)

  # Skip if has text or image elements (not text-as-path)
  return if state.has_text_element || state.has_image_element
  return if state.path_ds.empty?

  # Calculate metrics
  longest_d = state.path_ds.map(&:length).max
  total_bezier = state.path_ds.sum { |d| d.scan(/[CQcq]/).count }

  # Check if this is a text-as-path SVG
  if longest_d >= min_d_length && total_bezier >= min_bezier
    context.add_error(
      requirement_id: id,
      message: "Text appears to be rendered as paths (d-length: #{longest_d}, " \
               "beziers: #{total_bezier}). Consider using <text> elements " \
               "for better accessibility and smaller file size.",
      node: nil,
      severity: :warning,
    )
  end
end