Use this reference to find the main component classes, page drawing API, security options, image and compression support, and working Pascal examples directly in the web help
API, example, conformance, preflight, and workflow topics are available as standalone web pages
Eight hard-to-match differentiators, the supporting evidence, and the audiences HotPDF is built for — on one page: native source with no DLL, full OpenType shaping, in-process PFX signing, PAdES, three-axis compliance, the multi-gigabyte Direct File API and more
See the core selling pointsCreate documents, configure output, manage metadata, protect files, and finalize generated PDFs
THotPDF classReview loaded-document resolution, direct-file handling, xref-stream parsing, conformance output, and shaping helper workflows
Advanced workflow methodsEdit, merge, inspect, sign, search, print, display, and recover existing PDFs through loaded-document APIs with multi-widget form editing, complete annotation editing, automatic bare-link activation, and cache-aware VCL viewing
Loaded document toolkitEvaluate bounded calculation and validation scripts, regenerate variable-text appearances, resolve annotation states, and flatten selected fields under signature policies
Advanced AcroForm processingInspect and sanitise RichMedia assets, flatten indexed XFA data with bounded FormCalc, and round-trip every supported XFDF annotation subtype
Interactive document processingCreate RSA-PSS signatures, validate PDF/X output conditions and overprint controls, inspect tagged reading order, and build metadata-rich PDF Portfolios
RSA-PSS signing · PDF Portfolio collectionsResolve Unicode scalars through script-specific font chains, inspect actionable missing-glyph diagnostics, and emit CJK text with Identity-V and OpenType vertical metrics
Font fallback and vertical textMeasure and split reusable elements into owned continuations, compose stable background, header, footer, and foreground layers, stage completed pages in file-backed storage, and inspect bounded layout diagnostics
Constrained streaming layoutRender large loaded pages in bounded slices and cancel loading, rendering, optimisation, validation, and signing through one caller-owned token
Progressive rendering and cancellationCache rendered pages by effective viewer state, override ICC rendering intent, report or reject unsupported page content, and inspect unified operation costs
Rendering diagnostics and telemetryRender isolated and knockout transparency groups, luminosity soft masks, complete Type 3 glyph procedures, and clipped JPEG 2000 regions
Advanced rendering semanticsValidate free lists, generation transitions, duplicate definitions, and shadowed revision offsets, then relocate or rebuild damaged xref data under bounded limits
Cross-reference recoveryWrite dependency-ordered PDFs with first-page and shared-object hint tables for fast display over byte-range transports
Linearized output and fast web viewDecode strict ASCII and compression filters through memory-to-disk spill buffers, select deterministic high-ratio Flate output, run bounded parallel image jobs, and rewrite only when output shrinks
Stream extraction, optimization, budgets, and diagnosticsRead source-file windows, expose linearized first-page readiness from disjoint HTTP ranges, track object lifecycle states, and safely release decoded object-stream caches
Scalable and random-access loadingUse bounded weighted object caching, streaming SHA-256 keys, persistent font-subset reuse, and a recoverable rendered-page cache with immediate LRU limit enforcement
Cache infrastructureVerify RSA, RSA-PSS, ECDSA, Ed25519, Ed448, extension-gated ML-DSA, and RFC 3161 signatures, use callback, remote, or PKCS#11 signing providers, and inspect DocMDP and FieldMDP structures
Modern signature providers and permissionsValidate and register ICC v2/v4 profiles, render ICCBased vector and image colours to sRGB, and honour PDF rendering intents
RegisterICCProfileExplore the HotPDF overview for forms, annotations, secure signatures, conformance, layers, graphics, images, text, large files, and stream output capabilities
HotPDF OverviewDraw text, paths, curves, images, metafiles, annotations, and barcode output on the active page
THPDFPage classReview THPDFBarcode, barcode option enums, simple bar records, and Simple* encoder functions
HPDFBarcode unit referenceReview supported bitmap, TIFF, JPEG2000, JBIG2, EMF, and WMF workflows
Supported image formatsUnderstand FlateDecode, LZW, JBIG2, JPEG, JPEG2000, and bundled native compression paths
Compression overviewGenerate structure reports, apply profiles, write JSON or HTML, aggregate batch runs, and review diagnostics
Preflight cookbookApply reusable intake policies, read WTPDF declarations, run bounded validation jobs, and repair metadata independently
Validation policies and WTPDFControl initial display, print preferences, single-page, column, and two-page cover-spread layouts, page mode, and related PDF viewer settings
ViewerPreferences referenceOpen runnable examples for document creation, drawing, encryption, font embedding, paragraphs, and outlines
Example topics