PaperForge.FontRegistry (PaperForge v0.2.0)

Stores the standard PDF fonts registered in a document.

Each font is registered only once. Repeated uses of the same font reuse both its internal resource name and its indirect object reference.

Resource names are generated sequentially:

F1
F2
F3

Summary

Types

t()

Functions

all(registry)

Returns all registered fonts sorted by their resource identifier.

fetch(registry, font_key)

Fetches a registered font.

fetch!(registry, font_key)

Fetches a registered font and raises when it does not exist.

keys(registry)

Returns all registered font keys.

new()

Creates an empty font registry.

next_resource_name(registry)

Returns the resource name that will be assigned to the next new font.

register(registry, font_key, reference)

Registers a built-in PDF font.

registered?(registry, font_key)

Returns whether a font has already been registered.

resource_dictionary(registry, font_keys)

Creates a PDF /Font resource dictionary for selected fonts.

Types

t()

@type t() :: %PaperForge.FontRegistry{
  fonts: %{optional(atom()) => PaperForge.Font.t()},
  next_resource_id: pos_integer()
}

Functions

all(registry)

@spec all(t()) :: [PaperForge.Font.t()]

Returns all registered fonts sorted by their resource identifier.

fetch(registry, font_key)

@spec fetch(t(), atom()) :: {:ok, PaperForge.Font.t()} | :error

Fetches a registered font.

Returns {:ok, font} or :error.

fetch!(registry, font_key)

@spec fetch!(t(), atom()) :: PaperForge.Font.t()

Fetches a registered font and raises when it does not exist.

keys(registry)

@spec keys(t()) :: [atom()]

Returns all registered font keys.

new()

@spec new() :: t()

Creates an empty font registry.

next_resource_name(registry)

@spec next_resource_name(t()) :: binary()

Returns the resource name that will be assigned to the next new font.

register(registry, font_key, reference)

@spec register(
  t(),
  atom(),
  PaperForge.Reference.t()
) :: {t(), PaperForge.Font.t()}

Registers a built-in PDF font.

The reference must point to the font dictionary previously added to the PDF document.

When the font already exists, the registry and existing font are returned unchanged.

Example

{registry, font} =
  PaperForge.FontRegistry.register(
    registry,
    :helvetica_bold,
    reference
  )

font.resource_name
#=> "F1"

registered?(registry, font_key)

@spec registered?(t(), atom()) :: boolean()

Returns whether a font has already been registered.

resource_dictionary(registry, font_keys)

@spec resource_dictionary(
  t(),
  [atom()]
) :: map()

Creates a PDF /Font resource dictionary for selected fonts.

Example result

%{
  "F1" => %PaperForge.Reference{
    object_id: 3,
    generation: 0
  },
  "F2" => %PaperForge.Reference{
    object_id: 7,
    generation: 0
  }
}

Duplicate font keys are ignored.