Monochrome SVG fill patterns — the hatching vocabulary of a 1970s technical report.
Each preset expands to a unique, deterministic <pattern> element id. Use
the preset atom as a fill reference:
Bland.bar(fig, categories, values, hatch: :diagonal)Presets
The shipped presets (in the order you'd typically use them for a multi-series plot, maximizing visual separation):
:solid_black— fully filled black:solid_white— blank (paper color):diagonal— 45° lines, medium density:anti_diagonal— 135° lines, medium density:crosshatch— 45° + 135°:horizontal— horizontal rules:vertical— vertical rules:grid— square grid:dots_sparse— small dots, wide spacing:dots_dense— small dots, tight spacing:brick— running-bond brick:zigzag— repeating zigzag line:checker— 8x8 checker tiling:dashed_h— interrupted horizontal dashes:diagonal_dense— tightly packed 45° lines
All presets are rendered with 1px black lines on a transparent ground so they compose with any theme stroke color.
Custom patterns
Build your own with define/3:
Bland.Patterns.define("my-hatch", {10, 10}, ~s|<line x1="0" y1="0" x2="10" y2="10" stroke="black"/>|)Summary
Functions
Returns the next n patterns from the cycle, skipping any already used.
Defines a custom pattern inline. Returns an iodata <pattern> element
suitable for placing in a <defs> block. id is the DOM id you will
reference via fill="url(#<id>)".
Emits the SVG <pattern> defs for every preset named in names.
Returns an SVG fill attribute value for a preset. Solid presets return
color names; hatch presets return "url(#bland-pattern-...)".
Canonical DOM id for a preset.
Returns the list of preset names in a recommended cycling order. When a multi-series plot does not specify a per-series pattern, the renderer walks this list.
Functions
@spec cycle(non_neg_integer(), [atom()]) :: atom()
Returns the next n patterns from the cycle, skipping any already used.
Defines a custom pattern inline. Returns an iodata <pattern> element
suitable for placing in a <defs> block. id is the DOM id you will
reference via fill="url(#<id>)".
Emits the SVG <pattern> defs for every preset named in names.
Duplicates are filtered. :solid_black and :solid_white emit no defs;
they are handled as direct fills ("black", "white").
Returns an SVG fill attribute value for a preset. Solid presets return
color names; hatch presets return "url(#bland-pattern-...)".
Canonical DOM id for a preset.
@spec preset_cycle() :: [atom()]
Returns the list of preset names in a recommended cycling order. When a multi-series plot does not specify a per-series pattern, the renderer walks this list.