README- ::equalAlignment::equal
- ::not_equalAlignment::not_equal
- ::equalCodeBackground::equal
- ::not_equalCodeBackground::not_equal
- TColumns
- ::ascender_ptFace::ascender_pt
- ::descender_ptFace::descender_pt
- ::height_ptFace::height_pt
- ::kerningFace::kerning
- ::line_gap_ptFace::line_gap_pt
- ::prawn_widthFace::prawn_width
- ::add_anchorFlow::add_anchor
- ::advance_pageFlow::advance_page
- ::at_page_topFlow::at_page_top
- ::column_boxFlow::column_box
- ::cursorFlow::cursor
- ::dest_xFlow::dest_x
- ::fitsFlow::fits
- ::fontFlow::font
- ::go_to_pageFlow::go_to_page
- ::height_ofFlow::height_of
- ::indentFlow::indent
- ::ink_lineFlow::ink_line
- ::itemsFlow::items
- ::line_itemsFlow::line_items
- ::marginFlow::margin
- ::markFlow::mark
- ::move_downFlow::move_down
- ::newFlow::new
- ::on_versoFlow::on_verso
- ::pad_bottomFlow::pad_bottom
- ::page_hFlow::page_h
- ::pushFlow::push
- ::start_new_pageFlow::start_new_page
- ::taredFlow::tared
- ::textFlow::text
- ::to_last_columnFlow::to_last_column
- ::typesetFlow::typeset
- ::typeset_boxFlow::typeset_box
- ::underlayFlow::underlay
- ::widthFlow::width
- ::width_ofFlow::width_of
- ::has_iconsFontCatalog::has_icons
- ::icon_glyphFontCatalog::icon_glyph
- ::loadFontCatalog::load
- ::svg_familiesFontCatalog::svg_families
- TFragment
- ::newHooks::new
- TIconSet
- TItem
- TLine
- TLineMetrics
- TLineRun
- TMark
- TPageSetup
- ::equalStyle::equal
- ::face_styleStyle::face_style
- ::not_equalStyle::not_equal
- ::faceTextContext::face
- Vbuild_items
- Vdashed_hrule
- Vdefault_font_files
- Vdefault_icon_font_files
- Vface_key
- Vhrule
- Vline_extent
- Vline_metrics
- Vpdf_anchor_name
- Vrect_item
- Vrgb_hex
- Vsource_wrap
- Vtypeset_lines
- Vvrule
prawn
Prawn's layout behaviour for MoonBit on moonbitlang/pagelayout: the document cursor and bounds, formatted text, font metrics, prawn-svg and prawn-table sizing
pdf
prawn
svg
typesetting
Author
Version
0.1.0
License
MIT
Repository
Last updated
13 hours ago
Downloads
14
Dependencies
#bobzhang/prawn
The layout of Prawn 2.4.0, the Ruby PDF
library Asciidoctor PDF
2.3.27 lays documents out with, for MoonBit, drawing through
moonbitlang/pagelayout.
It reproduces Prawn's measurements and decisions closely enough that
bobzhang/asciidoctor-pdf matches Ruby Asciidoctor PDF's
output.
| package | what it is |
|---|---|
| bobzhang/prawn | the document cursor, bounds, columns and pages (Flow), formatted text (Fragment, Style) and its line wrapping (typeset_lines, Flow::typeset, Flow::typeset_box), font metrics of TrueType and the standard AFM fonts (FontCatalog, Face) with fallback fonts and icon fonts |
| bobzhang/prawn/svg | a port of prawn-svg 0.34.2: SVG documents rendered into pagelayout graphic operations |
| bobzhang/prawn/table | prawn-table 0.2.2's sizing: column widths and row heights |
Where Prawn calls back into Asciidoctor PDF (its fragment callbacks for inline
images and destinations, and its font policy), a Flow takes Hooks from the
document:
let catalog = FontCatalog::load(files)
let flow = Flow::new(catalog, setup, hooks={ ..Hooks::new(), base_family: "Noto Serif" })
flow.start_new_page()
flow.typeset(fragments, line_metrics(1.15, flow.font(style), style.size), style)The module is developed in the asciidoctor.mbt repository together with the
PDF backend, and checked by its comparison with Ruby Asciidoctor PDF
(scripts/pdf_compare.mbtx).
#License
MIT, except for the third-party material listed in NOTICE: the
prawn-svg port (MIT, svg/LICENSE) and the parts adapted from Prawn and
prawn-table (Matz's terms for Ruby, LICENSES/LICENSE-prawn).
Alignment
CodeBackground
How far the background of a fragment of a highlighted source block
reaches, when not just its glyph box.
CodeBackground::not_equal
Columns
pub(all) struct Columns {
count : Int
stride : Double
current : Int
}A column box (Prawn's ColumnBox with reflow_margins): the bounds are
split into count columns gap apart; running out of room moves to
the next column at the box's top, and past the last one to a new page,
where the box starts at the page's top.
Face
pub(all) struct Face {
metrics : FaceMetrics
ascender : Int
descender : Int
line_gap : Int
kern : Map[Int, Double]
standard : Bool
}One face of the font catalog, with the metrics Prawn (the layout engine
behind Ruby asciidoctor-pdf) derives from it. Prawn works in 1/1000 em
and truncates every metric to an integer there; so does this.
Face::descender_pt
Positive depth below the baseline.
Face::height_pt
Prawn's font.height: ascender − descender + line gap.
Face::kerning
Kerning between two codepoints, 1/1000 em (negative tightens).
Flow
pub(all) struct Flow {
catalog : FontCatalog
setup : PageSetup
hooks : Hooks
model : PageModel
scratch : Bool
page_top : Double
top : Double
bottom : Double
page : Int
y : Double
left : Double
right : Double
columns : Columns?
last_line : (Line, Int, Double)?
last_line_first : Bool
taring : Int
inked : Bool
first_break_empty : Bool?
page_margins : (Int) -> (Double, Double)?
margin_left : Double
margin_right : Double
page_width_now : Double
page_height_now : Double
}Flow::add_anchor
Flow::advance_page
Move to the next page, creating it unless an earlier pass already did
(a block's background revisits pages its content spilled onto); in a
column box, to the next column first (Prawn's move_past_bottom).
Flow::column_box
Lay out body in count columns gap apart, starting at the cursor
(Prawn's column_box with reflow_margins: true); the cursor ends
where the first column did, or, when the box went on past it, at the
bottom of the last one.
Flow::cursor
Space left above the bottom margin (Prawn's cursor).
Flow::dest_x
A named destination for the block at the cursor (asciidoctor-pdf's
add_dest_for_block).
Flow::fits
Whether height fits below the cursor (prawn-table's fits_on_page?).
Flow::go_to_page
Make page index the current page (Prawn's go_to_page), in its
margins; the cursor is left where it is.
Flow::height_of
The height typeset would take for fragments in the current bounds
(asciidoctor-pdf's height_of_typeset_text), ignoring page breaks.
Flow::indent
Flow::ink_line
Draw one placed line on the current page.
Flow::line_items
The items that draw one placed line with its left edge at x0 and its
baseline at baseline: backgrounds, glyph runs, decorations, link
regions and anchors.
Flow::margin
asciidoctor-pdf's margin: nothing at the top of a page, a move down
when it fits, else a new page.
Flow::new
A flow over pages set up as setup, its text set from catalog, the
document answering hooks; scratch for a dry run.
Flow::on_verso
Whether the current page is a verso page (an even page number).
Flow::pad_bottom
The bottom padding of a padded box: a move down when it fits, else the
next page (Prawn's move_past_bottom).
Flow::page_h
The current page's height (the PDF's y axis is measured up from its
bottom).
Flow::start_new_page
Flow::tared
Ink body as tared content: captions and backgrounds, which do not
keep a block on a page by themselves.
Flow::to_last_column
In a column box, move to its last column (Prawn's
bounds.current_column = bounds.last_column), so the next page break
starts a new page.
Flow::typeset
Ink formatted text at the cursor, flowing onto new pages as needed —
asciidoctor-pdf's typeset_text over Prawn's text.
Flow::typeset_box
Prawn's formatted text box with a height (text_box): the lines of
fragments set width wide from x (the first one text_indent
further in, Prawn's indent_paragraphs), the first hanging from the
cursor plus the line padding, as many as fit in height. Returns the
fragments that did not fit and the baseline of the last line inked
(None when none was); the cursor does not move.
Flow::underlay
Slide make(page, top, bottom, first, last) underneath everything inked
since start, on every page from start to the cursor: the painter's
order of a background drawn before its content, without a dry run.
FontCatalog
pub struct FontCatalog {
faces : Map[String, Face]
registry : FontRegistry
legacy_icons : Map[String, String]
// private fields
}The font catalog of the theme: family → the four styles, and the
pagelayout registry holding them, which the renderer draws with; and
the icon sets (icons=font), each a font family of its own.
FontCatalog::has_icons
Whether the catalog can draw font icons (it has icon sets).
FontCatalog::icon_glyph
The glyph of icon name in icon set set, when the catalog has both.
FontCatalog::load
fn FontCatalog::load(files : Array[(String, Bool, Bool, Bytes)], icon_sets? : Array[IconSet], legacy_icon_mapping? : String, fallbacks? : Array[String]) -> FontCatalog raiseLoad a catalog from font files: (family, bold, italic, TrueType bytes),
with the icon sets icons=font draws from, asciidoctor-pdf's mapping of
Font Awesome 4 icon names (fa-legacy-mapping.yml), and the families a
character the text's font lacks is looked for in (fallbacks).
FontCatalog::svg_families
The families Prawn knows (font_families), with their styles: the
catalog's (not the icon sets'), and Prawn's built-in AFM families.
Fragment
A run of text in one style. An anchor fragment has no text and marks
a named destination at its position.
Hooks
What the document does where Prawn calls back into asciidoctor-pdf: the
fragment callbacks it registers (InlineImageArranger and
InlineImageRenderer for inline images, InlineDestinationMarker for
anchors), and its font policy. One per document: a font catalog may be
shared between documents, these may not.
IconSet
pub(all) struct IconSet {
name : String
font : Bytes
legend : String
}An icon font of prawn-icon (data/fonts/<set>/): the set's name (fas,
far, fab, fi, pf), its TrueType font and its legend, which names
each glyph: name: glyph lines (fire: "…", under the set's key in
prawn-icon's <set>.yml; the bundled @icons.fonts() have their own
tables, <set>/glyphs.txt, made from the fonts' projects).
Item
pub(all) struct Item {
unit : Int
fragment : Int
fit : Double
draw : Double
kern : Double
hard_break : Bool
anchor : String?
offset : Int
}Line
LineMetrics
pub(all) struct LineMetrics {
leading : Double
padding_top : Double
padding_bottom : Double
}Prawn's line metrics for a line height factor (asciidoctor-pdf's
calc_line_metrics).
LineRun
One placed run of a line; x is relative to the line's left edge.
Mark
pub(all) struct Mark {
page : Int
y : Double
item : Int
}A point in the flow: page, cursor, and how many items the page held,
so backgrounds can be slid underneath content inked after it.
PageSetup
pub(all) struct PageSetup {
width : Double
height : Double
margin_top : Double
margin_right : Double
margin_bottom : Double
margin_left : Double
}The page size and margins a document starts with (asciidoctor-pdf's
build_pdf_options: page_size, page_layout, page_margin), in
points.
Style
pub(all) struct Style {
family : String
size : Double
bold : Bool
italic : Bool
color : Color
link : LinkTarget?
background : Color?
script : Int
border_offset : Double
underline : Bool
strike : Bool
wj : Bool
image : Int
callback : Int
doc_bold : Bool
doc_italic : Bool
font_set : Bool
text_transform : String?
code_background : CodeBackground?
linenum : Bool
line_mark : Bool
wrap_break : Bool
} derive(Eq)Character formatting of a fragment.
Style::face_style
The (bold, italic) face a fragment is set in, as Prawn's arranger picks
it (apply_font_settings): a fragment whose markup names a font or a
bold or italic style takes exactly those styles; any other fragment is
set in the document font, whatever its style.
TextContext
What text is set with: the font catalog and the document's hooks.
TextContext::face
build_items
dashed_hrule
A dashed horizontal rule (dashes and gaps four times its width, as
Prawn's dash in asciidoctor-pdf's dashed style), as filled segments.
default_font_files
The file names of the default theme's catalog (asciidoctor-pdf's
data/fonts): (family, bold, italic, file).
default_icon_font_files
The icon sets of prawn-icon 3.0.0 (its data/fonts): (set, font file,
legend file), relative to that directory.
hrule
A horizontal rule width thick centred on y.
line_extent
The ascender, descender and height a placed line takes: its fragments'
largest, or the document font's for an empty line. With
normalize_line_height, the document font's count on every line, as
asciidoctor-pdf's arranger puts a zero-width space in that font at the
start of each line (so a line of code in a list takes the prose line's
height, not the smaller one of the monospace font).
pdf_anchor_name
fn pdf_anchor_name(id : String) -> StringThe PDF destination name for an id (asciidoctor-pdf's
derive_anchor_from_id): the id itself when it is ASCII, else 0x and
the hex of its UTF-8 bytes.
rect_item
source_wrap
asciidoctor-pdf's SourceWrap: fragments (a numbered source block, each
line starting with its line number, Style::linenum) with every line
that wraps in width broken where it wraps: a line break, then the
number's blank (a no-break space and spaces as wide as the number, in
no style of its own), the line's highlight mark if it has one
(Style::line_mark), and the rest of the line without the blanks it
starts with. A number (or blank) wider than the line breaks before its
trailing blanks, the line's text going on a line of its own, as Prawn
breaks it. Each pass breaks the first line that wraps, consuming some of
the source's text or of a number's blanks, so the passes end.
None when a line cannot fit, as Prawn raises Prawn::Errors::CannotFit:
its number (or blank) without its blanks is wider than the line, or it
would hold nothing else.
typeset_lines
Break fragments into lines of at most width (the first line
first_width, and with indent_paragraphs also each line after a hard
break: Prawn's indent_paragraphs starts a paragraph there) and place
them.
Install
Download zipPrawn's layout behaviour for MoonBit on moonbitlang/pagelayout: the document cursor and bounds, formatted text, font metrics, prawn-svg and prawn-table sizing
pdfprawnsvgtypesetting
MIT
Updated 13 hours ago
14 downloadsDependencies