write

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v0.8.0 Latest Latest
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 Go to latest Published: Jan 11, 2026 License: MIT Imports: 22 Imported by: 0

Documentation

Overview

Package writer provides PDF writing capabilities including page content streams

Package writer provides PDF writing capabilities including image embedding

Package writer provides PDF writing capabilities including page creation

Package writer provides PDF writing capabilities

Index

Constants

This section is empty.

Variables

View Source 
var (
	PageSizeLetter = PageSize{612, 792}  // 8.5 x 11 inches
	PageSizeA4     = PageSize{595, 842}  // 210 x 297 mm
	PageSizeLegal  = PageSize{612, 1008} // 8.5 x 14 inches
	PageSizeA3     = PageSize{842, 1191} // 297 x 420 mm
	PageSizeA5     = PageSize{420, 595}  // 148 x 210 mm
)

Standard page sizes

Functions

func CreateEncryptionDictionary 

func CreateEncryptionDictionary(encrypt *types.PDFEncryption) []byte

CreateEncryptionDictionary creates the encryption dictionary object content for V5

func SetupAES256Encryption 

func SetupAES256Encryption(userPassword, ownerPassword []byte, fileID []byte, permissions int32, encryptMetadata bool) (*types.PDFEncryption, error)

SetupAES256Encryption creates an encryption dictionary for AES-256 (V5/R5/R6) Based on ISO 32000-2 section 7.6.4

Types

type ContentStream 

type ContentStream struct {
	// contains filtered or unexported fields
}

ContentStream builds PDF page content streams

func NewContentStream 

func NewContentStream() *ContentStream

NewContentStream creates a new content stream builder

func (*ContentStream) BeginText 

func (cs *ContentStream) BeginText() *ContentStream

BeginText starts a text object (BT operator)

func (*ContentStream) Bytes 

func (cs *ContentStream) Bytes() []byte

Bytes returns the content stream data

func (*ContentStream) ClosePath 

func (cs *ContentStream) ClosePath() *ContentStream

ClosePath closes the current subpath (h operator)

func (*ContentStream) ClosePathStroke 

func (cs *ContentStream) ClosePathStroke() *ContentStream

ClosePathStroke closes and strokes the path (s operator)

func (*ContentStream) CurveTo added in v0.8.0 

func (cs *ContentStream) CurveTo(x1, y1, x2, y2, x3, y3 float64) *ContentStream

CurveTo appends a cubic Bezier curve (c operator)

func (*ContentStream) CurveToV added in v0.8.0 

func (cs *ContentStream) CurveToV(x2, y2, x3, y3 float64) *ContentStream

CurveToV appends a cubic Bezier curve (v operator) - first control point = current point

func (*ContentStream) CurveToY added in v0.8.0 

func (cs *ContentStream) CurveToY(x1, y1, x3, y3 float64) *ContentStream

CurveToY appends a cubic Bezier curve (y operator) - second control point = end point

func (*ContentStream) DrawImage 

func (cs *ContentStream) DrawImage(imageName string) *ContentStream

DrawImage draws an image XObject (Do operator) imageName should be a resource name like "/Im1" The image is drawn with its lower-left corner at the origin You should use SetMatrix to position and scale it first

func (*ContentStream) DrawImageAt 

func (cs *ContentStream) DrawImageAt(imageName string, x, y, width, height float64) *ContentStream

DrawImageAt draws an image at a specific position and size

func (*ContentStream) EndText 

func (cs *ContentStream) EndText() *ContentStream

EndText ends a text object (ET operator)

func (*ContentStream) Fill 

func (cs *ContentStream) Fill() *ContentStream

Fill fills the current path (f operator)

func (*ContentStream) FillStroke 

func (cs *ContentStream) FillStroke() *ContentStream

FillStroke fills and strokes the current path (B operator)

func (*ContentStream) LineTo 

func (cs *ContentStream) LineTo(x, y float64) *ContentStream

LineTo appends a line segment (l operator)

func (*ContentStream) MoveTextPosition added in v0.8.0 

func (cs *ContentStream) MoveTextPosition(tx, ty float64) *ContentStream

MoveTextPosition moves the text position relative to current position (TD operator) This is equivalent to: SetTextLeading(-ty); SetTextPosition(tx, ty)

func (*ContentStream) MoveTo 

func (cs *ContentStream) MoveTo(x, y float64) *ContentStream

MoveTo starts a new subpath (m operator)

func (*ContentStream) NextLine 

func (cs *ContentStream) NextLine() *ContentStream

NextLine moves to the next line (T* operator)

func (*ContentStream) Raw 

func (cs *ContentStream) Raw(data string) *ContentStream

Raw writes raw content stream data

func (*ContentStream) Rectangle 

func (cs *ContentStream) Rectangle(x, y, width, height float64) *ContentStream

Rectangle appends a rectangle (re operator)

func (*ContentStream) RestoreState 

func (cs *ContentStream) RestoreState() *ContentStream

RestoreState restores the previous graphics state (Q operator)

func (*ContentStream) SaveState 

func (cs *ContentStream) SaveState() *ContentStream

SaveState saves the current graphics state (q operator)

func (*ContentStream) Scale 

func (cs *ContentStream) Scale(sx, sy float64) *ContentStream

Scale scales the coordinate system

func (*ContentStream) SetCharSpacing 

func (cs *ContentStream) SetCharSpacing(spacing float64) *ContentStream

SetCharSpacing sets character spacing (Tc operator)

func (*ContentStream) SetFillColorGray 

func (cs *ContentStream) SetFillColorGray(gray float64) *ContentStream

SetFillColorGray sets the fill color to grayscale (g operator)

func (*ContentStream) SetFillColorRGB 

func (cs *ContentStream) SetFillColorRGB(r, g, b float64) *ContentStream

SetFillColorRGB sets the fill color (rg operator)

func (*ContentStream) SetFont 

func (cs *ContentStream) SetFont(fontName string, size float64) *ContentStream

SetFont sets the font and size (Tf operator) fontName should be a resource name like "/F1"

func (*ContentStream) SetLineDash added in v0.8.0 

func (cs *ContentStream) SetLineDash(dashArray []float64, dashPhase float64) *ContentStream

SetLineDash sets the line dash pattern (d operator) dashArray is the dash pattern, dashPhase is the phase offset

func (*ContentStream) SetLineWidth 

func (cs *ContentStream) SetLineWidth(width float64) *ContentStream

SetLineWidth sets the line width (w operator)

func (*ContentStream) SetMatrix 

func (cs *ContentStream) SetMatrix(a, b, c, d, e, f float64) *ContentStream

SetMatrix sets the current transformation matrix (cm operator)

func (*ContentStream) SetStrokeColorGray 

func (cs *ContentStream) SetStrokeColorGray(gray float64) *ContentStream

SetStrokeColorGray sets the stroke color to grayscale (G operator)

func (*ContentStream) SetStrokeColorRGB 

func (cs *ContentStream) SetStrokeColorRGB(r, g, b float64) *ContentStream

SetStrokeColorRGB sets the stroke color (RG operator)

func (*ContentStream) SetTextLeading 

func (cs *ContentStream) SetTextLeading(leading float64) *ContentStream

SetTextLeading sets the text leading (TL operator)

func (*ContentStream) SetTextMatrix 

func (cs *ContentStream) SetTextMatrix(a, b, c, d, e, f float64) *ContentStream

SetTextMatrix sets the text matrix (Tm operator)

func (*ContentStream) SetTextPosition 

func (cs *ContentStream) SetTextPosition(x, y float64) *ContentStream

SetTextPosition sets the text position (Td operator)

func (*ContentStream) SetTextRenderMode added in v0.8.0 

func (cs *ContentStream) SetTextRenderMode(mode int) *ContentStream

SetTextRenderMode sets the text rendering mode (Tr operator) Mode: 0=fill, 1=stroke, 2=fill+stroke, 3=invisible, 4=fill+clip, 5=stroke+clip, 6=fill+stroke+clip, 7=clip

func (*ContentStream) SetTextRise 

func (cs *ContentStream) SetTextRise(rise float64) *ContentStream

SetTextRise sets text rise (Ts operator)

func (*ContentStream) SetWordSpacing 

func (cs *ContentStream) SetWordSpacing(spacing float64) *ContentStream

SetWordSpacing sets word spacing (Tw operator)

func (*ContentStream) ShowText 

func (cs *ContentStream) ShowText(text string) *ContentStream

ShowText displays a string (Tj operator)

func (*ContentStream) ShowTextArray added in v0.8.0 

func (cs *ContentStream) ShowTextArray(elements []interface{}) *ContentStream

ShowTextArray displays text with individual character positioning (TJ operator) Each element in the array can be either a string or a number (adjustment in thousandths of a text space unit) Example: ShowTextArray([]interface{}{"Hello", -50, "World"}) moves "World" 0.05 units to the left

func (*ContentStream) ShowTextHex added in v0.8.0 

func (cs *ContentStream) ShowTextHex(hexString string) *ContentStream

ShowTextHex displays text using hexadecimal string notation (TJ with hex) Useful for characters that are difficult to escape in literal strings

func (*ContentStream) ShowTextNextLine 

func (cs *ContentStream) ShowTextNextLine(text string) *ContentStream

ShowTextNextLine moves to next line and shows text (' operator)

func (*ContentStream) String 

func (cs *ContentStream) String() string

String returns the content stream as a string

func (*ContentStream) Stroke 

func (cs *ContentStream) Stroke() *ContentStream

Stroke strokes the current path (S operator)

func (*ContentStream) Translate 

func (cs *ContentStream) Translate(tx, ty float64) *ContentStream

Translate moves the origin

type Dictionary 

type Dictionary map[string]interface{}

Dictionary represents a PDF dictionary

type ImageInfo 

type ImageInfo struct {
	ObjectNum  int    // Object number of the image XObject
	Width      int    // Image width in pixels
	Height     int    // Image height in pixels
	ColorSpace string // PDF color space name (e.g., "/DeviceRGB")
	Name       string // Resource name (e.g., "/Im1")
}

ImageInfo contains information about an embedded image

type PDFObject 

type PDFObject struct {
	Number     int
	Generation int
	Content    []byte     // Raw content (dictionary, stream, etc.)
	Stream     []byte     // Stream data (if this is a stream object)
	Dict       Dictionary // Parsed dictionary (for convenience)
	IsFree     bool
}

PDFObject represents a PDF object with its content

type PDFWriter 

type PDFWriter struct {
	// contains filtered or unexported fields
}

PDFWriter builds PDF files from scratch

func NewPDFWriter 

func NewPDFWriter() *PDFWriter

NewPDFWriter creates a new PDF writer

func (*PDFWriter) AddImage 

func (w *PDFWriter) AddImage(imgData []byte, name string) (*ImageInfo, error)

AddImage adds a generic image (PNG, etc.) to the PDF The image is converted to raw RGB/Gray data and compressed with FlateDecode

func (*PDFWriter) AddJPEGImage 

func (w *PDFWriter) AddJPEGImage(jpegData []byte, name string) (*ImageInfo, error)

AddJPEGImage adds a JPEG image to the PDF and returns its info JPEG images are embedded directly without re-encoding (DCTDecode)

func (*PDFWriter) AddObject 

func (w *PDFWriter) AddObject(content []byte) int

AddObject adds a new object and returns its object number

func (*PDFWriter) AddStreamObject 

func (w *PDFWriter) AddStreamObject(dict Dictionary, data []byte, compress bool) int

AddStreamObject adds a stream object with dictionary and data

func (*PDFWriter) Bytes 

func (w *PDFWriter) Bytes() ([]byte, error)

Bytes returns the complete PDF as a byte slice

func (*PDFWriter) GetObject 

func (w *PDFWriter) GetObject(objNum int) ([]byte, error)

GetObject returns an object's content (for reading existing objects)

func (*PDFWriter) NewPageBuilder 

func (w *PDFWriter) NewPageBuilder(size PageSize) *PageBuilder

NewPageBuilder creates a new page builder

func (*PDFWriter) NextObjectNumber 

func (w *PDFWriter) NextObjectNumber() int

NextObjectNumber returns the next available object number

func (*PDFWriter) SetEncryptRef 

func (w *PDFWriter) SetEncryptRef(objNum int)

SetEncryptRef sets the encrypt dictionary object reference

func (*PDFWriter) SetEncryption 

func (w *PDFWriter) SetEncryption(encryptInfo *types.PDFEncryption, fileID []byte)

SetEncryption enables encryption for the output PDF

func (*PDFWriter) SetInfo 

func (w *PDFWriter) SetInfo(objNum int)

SetInfo sets the info dictionary object reference

func (*PDFWriter) SetObject 

func (w *PDFWriter) SetObject(objNum int, content []byte)

SetObject sets or replaces an object at a specific number

func (*PDFWriter) SetRoot 

func (w *PDFWriter) SetRoot(objNum int)

SetRoot sets the root (catalog) object reference

func (*PDFWriter) SetStreamObject 

func (w *PDFWriter) SetStreamObject(objNum int, dict Dictionary, data []byte, compress bool)

SetStreamObject sets a stream object at a specific number

func (*PDFWriter) SetVersion 

func (w *PDFWriter) SetVersion(version string)

SetVersion sets the PDF version (e.g., "1.7")

func (*PDFWriter) SetupEncryptionWithPasswords 

func (w *PDFWriter) SetupEncryptionWithPasswords(userPassword, ownerPassword []byte, permissions int32, encryptMetadata bool) (int, error)

SetupEncryptionWithPasswords is a convenience function that sets up encryption and creates the encryption dictionary object Returns the encryption dictionary object number

func (*PDFWriter) Write 

func (w *PDFWriter) Write(out io.Writer) error

Write outputs the complete PDF to the given writer

type PageBuilder 

type PageBuilder struct {
	// contains filtered or unexported fields
}

PageBuilder helps build PDF pages

func (*PageBuilder) AddEmbeddedFont 

func (pb *PageBuilder) AddEmbeddedFont(f *font.Font) (string, error)

AddEmbeddedFont adds an embedded TrueType/OpenType font and returns the resource name The font will be subset to include only the characters added via font.AddString() or font.AddRune()

func (*PageBuilder) AddImage 

func (pb *PageBuilder) AddImage(info *ImageInfo) string

AddImage adds an image and returns the resource name

func (*PageBuilder) AddStandardFont 

func (pb *PageBuilder) AddStandardFont(fontName string) string

AddStandardFont adds a standard PDF font (Helvetica, Times-Roman, etc.) Returns the resource name to use (e.g., "/F1")

func (*PageBuilder) Build 

func (pb *PageBuilder) Build(pagesObjNum int) int

Build finalizes the page and returns the page object number

func (*PageBuilder) Content 

func (pb *PageBuilder) Content() *ContentStream

Content returns the content stream for adding graphics/text

type PageSize 

type PageSize struct {
	Width  float64
	Height float64
}

PageSize represents standard page dimensions in points (1 point = 1/72 inch)

type SimplePDFBuilder 

type SimplePDFBuilder struct {
	// contains filtered or unexported fields
}

SimplePDFBuilder provides a high-level API for creating simple PDFs

func NewSimplePDFBuilder 

func NewSimplePDFBuilder() *SimplePDFBuilder

NewSimplePDFBuilder creates a new simple PDF builder

func (*SimplePDFBuilder) AddPage 

func (b *SimplePDFBuilder) AddPage(size PageSize) *PageBuilder

AddPage adds a new page and returns a page builder

func (*SimplePDFBuilder) Bytes 

func (b *SimplePDFBuilder) Bytes() ([]byte, error)

Bytes returns the complete PDF

func (*SimplePDFBuilder) FinalizePage 

func (b *SimplePDFBuilder) FinalizePage(pb *PageBuilder)

FinalizePage adds a built page to the document

func (*SimplePDFBuilder) Pages 

func (b *SimplePDFBuilder) Pages() []int

Pages returns the list of page object numbers

func (*SimplePDFBuilder) PagesObjNum 

func (b *SimplePDFBuilder) PagesObjNum() int

PagesObjNum returns the pages object number

func (*SimplePDFBuilder) Writer 

func (b *SimplePDFBuilder) Writer() *PDFWriter

Writer returns the underlying PDF writer for advanced operations

type XFABuilder 

type XFABuilder struct {
	// contains filtered or unexported fields
}

XFABuilder builds PDFs with XFA content

func NewXFABuilder 

func NewXFABuilder(verbose bool) *XFABuilder

NewXFABuilder creates a new XFA PDF builder

func (*XFABuilder) BuildFromOriginal 

func (b *XFABuilder) BuildFromOriginal(originalPDF []byte, updatedStreams map[string][]byte, encryptInfo *types.PDFEncryption) ([]byte, error)

BuildFromOriginal rebuilds a PDF preserving structure but updating XFA streams

func (*XFABuilder) BuildFromXFA 

func (b *XFABuilder) BuildFromXFA(streams []XFAStreamData) ([]byte, error)

BuildFromXFA creates a complete PDF from XFA stream data

type XFAStreamData 

type XFAStreamData struct {
	Name     string
	Data     []byte
	Compress bool
}

XFAStreamData represents XFA stream data with its name

Source Files

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