Documentation
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Index ¶
- func AppendLineEndAfter(head, n Node) (Node, Node)
- func Debug(n Node)
- func DebugToFile(n Node, fn string) error
- func DebugToString(n Node) string
- func Dimensions(start Node, stop Node, dir Direction) (bag.ScaledPoint, bag.ScaledPoint, bag.ScaledPoint)
- func GetAttribute(n Node, attr string) (any, bool)
- func IsNode(arg any) bool
- func Linebreak(n Node, settings *LinebreakSettings) (*VList, []*Breakpoint)
- func SetAttribute(n Node, attr string, val any)
- func String(n Node) string
- func StringValue(n Node) string
- type ActionType
- type Breakpoint
- type Direction
- type Disc
- type Glue
- type GlueOrder
- type GlueSubtype
- type Glyph
- type H
- type HList
- type HpackOption
- type Image
- type Kern
- type Lang
- type LinebreakSettings
- type Node
- type PDFDataOutput
- type Penalty
- type Rule
- type StartStop
- func (d *StartStop) Copy() Node
- func (d *StartStop) GetID() int
- func (d *StartStop) Name() string
- func (d *StartStop) Next() Node
- func (d *StartStop) Prev() Node
- func (d *StartStop) SetNext(n Node)
- func (d *StartStop) SetPrev(n Node)
- func (d *StartStop) String() string
- func (d *StartStop) Type() Type
- type StartStopFunc
- type Type
- type VList
- type VerticalAlignment
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func AppendLineEndAfter ¶
AppendLineEndAfter adds a penalty 10000, glue 0pt plus 1fil, penalty -10000 after n (the node lists starting with head). It returns the new head (if head is nil) and the penalty node (the tail of the list).
func DebugToFile ¶
DebugToFile writes an XML file with the node list.
func DebugToString ¶
DebugToString returns node list debug output.
func Dimensions ¶
func Dimensions(start Node, stop Node, dir Direction) (bag.ScaledPoint, bag.ScaledPoint, bag.ScaledPoint)
Dimensions returns the width, height and the depth of the node list starting at n and ending with the stop node or at the end if stop is nil. If dir is Horizontal, then calculate in horizontal mode, otherwise in vertical mode.
func GetAttribute ¶
GetAttribute returns the value of the attribute attr and true or nil and false if the attribute does not exist.
func Linebreak ¶
func Linebreak(n Node, settings *LinebreakSettings) (*VList, []*Breakpoint)
Linebreak breaks the node list starting at n into lines. Returns a VList of HLists and information about each line.
func SetAttribute ¶
SetAttribute sets the attribute attr on the node n.
func StringValue ¶
StringValue returns a short string representation of the node list starting at n.
Types ¶
type ActionType ¶
type ActionType int
ActionType represents a start/stop action such as a PDF link.
const ( // ActionNone represents no special action ActionNone ActionType = iota // ActionHyperlink represents a hyperlink. ActionHyperlink // ActionDest insets a PDF destination. ActionDest // ActionUserSetting allows user defined settings. ActionUserSetting )
func (ActionType) String ¶
func (at ActionType) String() string
type Breakpoint ¶
type Breakpoint struct {
Position Node
Pre Node
Line int
Fitness int
Width bag.ScaledPoint
R float64
Demerits int
// contains filtered or unexported fields
}
Breakpoint is a feasible break point.
func (*Breakpoint) String ¶
func (bp *Breakpoint) String() string
type Direction ¶
type Direction bool
Direction represents the direction of the node list. This can be horizontal or vertical.
type Disc ¶
type Disc struct {
Pre Node
Post Node
Replace Node
Penalty int // Added to the hyphen penalty
// contains filtered or unexported fields
}
A Disc represents a hyphenation point. Currently only the Penalty field is used.
func NewDiscWithContents ¶
NewDiscWithContents creates an initialized Disc node with the given contents
type Glue ¶
type Glue struct {
Subtype GlueSubtype
Width bag.ScaledPoint // The natural width of the glue.
Stretch bag.ScaledPoint // The stretchability of the glue, where width plus stretch = maximum width.
Shrink bag.ScaledPoint // The shrinkability of the glue, where width minus shrink = minimum width.
StretchOrder GlueOrder // The order of infinity of stretching.
ShrinkOrder GlueOrder // The order of infinity of shrinking.
// contains filtered or unexported fields
}
A Glue node has the value of a shrinking and stretching space
type GlueSubtype ¶
type GlueSubtype int
GlueSubtype is set wherever the glue comes from.
const ( // GlueDefault when no subtype is set GlueDefault GlueSubtype = iota // GlueLineStart is inserted left of the hlist during the line breaking GlueLineStart // GlueLineEnd is added at the end of each line in a paragraph so that copy // and paste works in PDF. GlueLineEnd )
type Glyph ¶
type Glyph struct {
Font *font.Font
// The font specific glyph id
Codepoint int
// A codepoint can contain more than one rune, for example a fi ligature
// contains f + i. Filling the components string is optional.
Components string
// The advance width of the box.
Width bag.ScaledPoint
// The height is the length above the base line.
Height bag.ScaledPoint
// The Depth is the length below the base line. For example the letter g has
// a depth > 0.
Depth bag.ScaledPoint
// Vertical displacement. Positive values move the glyph towards the top of
// the page.
YOffset bag.ScaledPoint
// This allows the glyph to be part of word hyphenation.
Hyphenate bool
// contains filtered or unexported fields
}
Glyph nodes represents a single visible entity such as a letter or a ligature.
type HList ¶
type HList struct {
Width bag.ScaledPoint
Height bag.ScaledPoint
Depth bag.ScaledPoint
Badness int
GlueSet float64 // The ratio of the glue. Positive means stretching, negative shrinking.
GlueSign uint8 // 0 = normal, 1 = stretching, 2 = shrinking
GlueOrder GlueOrder // The level of infinity
Shift bag.ScaledPoint // The displacement perpendicular to the progressing direction. Not used.
List Node // The list itself.
VAlign VerticalAlignment
// contains filtered or unexported fields
}
A HList is a container for a list which items are placed horizontally next to each other. The most convenient way to create a hlist is using node.HPack. The width, height, depth, badness and the glue settings are calculated when using node.HPack.
func HpackTo ¶
func HpackTo(firstNode Node, width bag.ScaledPoint) *HList
HpackTo returns a HList node with the node list as its list. The width is the desired width.
func HpackToWithEnd ¶
func HpackToWithEnd(firstNode Node, lastNode Node, width bag.ScaledPoint, opts ...HpackOption) *HList
HpackToWithEnd returns a HList node with nl as its list. The width is the desired width. The list stops at lastNode (including lastNode).
type HpackOption ¶
type HpackOption func(*hpackSetting)
HpackOption controls the packaging of the box.
func FontExpansion ¶
func FontExpansion(amount float64) HpackOption
FontExpansion sets the allowed font expansion (0-1).
func SqueezeOverfullBoxes ¶
func SqueezeOverfullBoxes(avoid bool) HpackOption
SqueezeOverfullBoxes avoids overfull boxes by shrinking more than allowed.
type Image ¶
type Image struct {
Width bag.ScaledPoint
Height bag.ScaledPoint
Img *image.Image
// contains filtered or unexported fields
}
An Image contains a reference to the image object.
type Kern ¶
type Kern struct {
// The displacement in progression direction.
Kern bag.ScaledPoint
// contains filtered or unexported fields
}
A Kern is a small space between glyphs.
type Lang ¶
type Lang struct {
Lang *lang.Lang // The language setting for the following nodes.
// contains filtered or unexported fields
}
A Lang is a node that sets the current language.
func NewLangWithContents ¶
NewLangWithContents creates an initialized Lang node with the given contents
type LinebreakSettings ¶
type LinebreakSettings struct {
SqueezeOverfullBoxes bool
DemeritsFitness int
DoublehyphenDemerits int
HangingPunctuationEnd bool
FontExpansion float64
HSize bag.ScaledPoint
Hyphenpenalty int
Indent bag.ScaledPoint
IndentRows int
LineEndGlue *Glue
LineHeight bag.ScaledPoint
LineStartGlue *Glue
OmitLastLeading bool
Tolerance float64
}
LinebreakSettings controls the line breaking algorithm.
func NewLinebreakSettings ¶
func NewLinebreakSettings() *LinebreakSettings
NewLinebreakSettings returns a settings struct with defaults initialized.
type Node ¶
type Node interface {
Next() Node
Prev() Node
SetNext(Node)
SetPrev(Node)
GetID() int
Type() Type
Name() string
Copy() Node
}
Node represents any kind of node
func DeleteFromList ¶
DeleteFromList removes the node cur from the list starting at head. The possible new head is returned.
func InsertAfter ¶
InsertAfter inserts the node insert right after cur. If cur is nil then insert is the new head. This method returns the head node.
func InsertBefore ¶
InsertBefore inserts the node insert before the current not cur. It returns the (perhaps) new head node.
type PDFDataOutput ¶
type PDFDataOutput int
PDFDataOutput defines the location of inserted PDF data.
const ( // PDFOutputNone ignores any movement commands. PDFOutputNone PDFDataOutput = iota // PDFOutputHere inserts ET and moves to current position before inserting // the PDF data. PDFOutputHere // PDFOutputDirect inserts the PDF data without leaving the text mode with ET. PDFOutputDirect // PDFOutputPage inserts ET before writing the PDF data. PDFOutputPage // PDFOutputLowerLeft moves to the lower left corner before inserting the // PDF data. PDFOutputLowerLeft )
type Penalty ¶
type Penalty struct {
Penalty int // Value
Width bag.ScaledPoint // Width of the penalty
// contains filtered or unexported fields
}
A Penalty is a valid horizontal or vertical break point. The higher the penalty the less likely the break occurs at this penalty. Anything below or equal -10000 is considered a forced break, anything higher than or equal to 10000 is considered a disallowed break.
func IsPenalty ¶
IsPenalty returns the value of the element and true, if the element is a Penalty node.
type Rule ¶
type Rule struct {
// PDF code that gets output before the rule.
Pre string
// PDF Code after drawing the rule.
Post string
// Hide makes the rule invisible, no colored area is drawn. Used to make Pre
// and Post appear in the output with the given dimensions.
Hide bool
Width bag.ScaledPoint
Height bag.ScaledPoint
Depth bag.ScaledPoint
// contains filtered or unexported fields
}
A Rule is a node represents a colored rectangular area.
type StartStop ¶
type StartStop struct {
Action ActionType
StartNode *StartStop
Position PDFDataOutput
ShipoutCallback StartStopFunc
// Value contains action specific contents
Value any
// contains filtered or unexported fields
}
A StartStop is a paired node type used for color switches, hyperlinks and such.
type StartStopFunc ¶
StartStopFunc is the type of the callback when this node is encountered in the node list. The returned string (if not empty) gets written to the PDF.
type Type ¶
type Type int
Type is the type of node.
const ( // TypeUnknown is a node which type is unknown. TypeUnknown Type = iota // TypeDisc is a Disc node. TypeDisc // TypeGlue is a Glue node. TypeGlue // TypeGlyph is a Glyph node. TypeGlyph // TypeHList is a HList node. TypeHList // TypeImage is a Image node. TypeImage // TypeKern is a Kern node. TypeKern // TypeLang is a Lang node. TypeLang // TypePenalty is a Penalty node. TypePenalty // TypeRule is a Rule node. TypeRule // TypeStartStop marks the beginning and end of a something interesting. TypeStartStop // TypeVList is a VList node. TypeVList )
type VList ¶
type VList struct {
Width bag.ScaledPoint
Height bag.ScaledPoint
Depth bag.ScaledPoint
GlueSet float64
GlueSign uint8
ShiftX bag.ScaledPoint
List Node
// contains filtered or unexported fields
}
A VList is a vertical list.
type VerticalAlignment ¶
type VerticalAlignment uint
VerticalAlignment sets the alignment in horizontal lists (hlist). The default alignment is VAlignBaseline which means that all items in the hlist have the same base line.
const ( // VAlignBaseline is the default alignment in hlists which has all items // aligned at the base line. VAlignBaseline VerticalAlignment = 0 // VAlignTop has all items in a hlist hanging down from the top like // stalactites in a cave. VAlignTop = 1 )
Source Files