deckcraft/docs/file-format-parity.md

File-format parity with PowerPoint

Last reviewed: 2026-10-10 · Last updated: 2026-10-12 · Change: minor (SmartArt text follows dsp:txXfrm; previous: trivial, Groups with a small legacy child coordinate space draw outlines, dashes, arrowheads and ink at their own width (#233)) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-10 · Last updated: 2026-10-13 · Change: trivial (Groups with a small legacy child coordinate space draw outlines, dashes, arrowheads and ink at their own width comments: modern threaded parts written, #70; groups with a small legacy child coordinate space draw outlines, dashes, arrowheads and ink at their own width (#233); previously major: created; formats taken from PowerPoint 16.113.4's Info.plist, PPTX coverage measured from crates/pptx) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-10 · Last updated: 2026-10-13 · Change: minor (EMF/WMF rectangle clip regions; previous: trivial, groups with a small legacy child space, #233) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-10 · Last updated: 2026-10-13 · Change: minor (embedded fonts read, written and drawn; MicroType Express subsets kept but not drawn; previously trivial: groups with a small legacy child coordinate space, #233) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-13 · Last updated: 2026-10-13 · Change: minor (owned corpus round-trip; notes-master header and footer text kept; previous: trivial, groups with a small legacy child coordinate space) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-13 · Last updated: 2026-10-13 · Change: minor (owned corpus for comments, links and actions, custom shows, rotated groups and inherited placeholders; paragraph defRPr and action sounds kept; previous: trivial, groups with a small legacy child coordinate space) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-13 · Last updated: 2026-10-13 · Change: minor (owned corpus for text effects, body layout, theme effects, fills, bevels and connectors; a run's inner shadow, reflection and soft edge, and a bevel preset with no kept 3-D XML, survive a save; previous: trivial, groups with a small legacy child coordinate space) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-14 · Last updated: 2026-10-14 · Change: minor (3-D model parts and animation bounce end round-trip; corpus_media.rs covers SmartArt and OLE XML, media bookmarks and trims, sections, fields, ink and timing) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-14 · Last updated: 2026-10-14 · Change: minor (chart trendlines round-trip; previously trivial: groups with a small legacy child coordinate space draw outlines, dashes, arrowheads and ink at their own width (#233); formats taken from PowerPoint 16.113.4's Info.plist, PPTX coverage measured from crates/pptx) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365) Last reviewed: 2026-10-14 · Last updated: 2026-10-14 · Change: minor (chart trendlines are drawn; previously minor: chart trendlines round-trip; groups with a small legacy child coordinate space draw outlines, dashes, arrowheads and ink at their own width (#233); formats taken from PowerPoint 16.113.4's Info.plist, PPTX coverage measured from crates/pptx) · Target: Microsoft PowerPoint for Mac 16.113 (Microsoft 365)

Every format PowerPoint reads or writes, DeckCraft's support, fidelity and how it is tested. Gaps are itemized in gaps.md. Dimension score: ~58% ready (estimated), 60–110 h to parity.

Weights inside this dimension: PPTX 70%, PDF export 10%, image export 5%, legacy binary formats 5%, everything else (templates, shows, macros, ODP, video, GIF, outline) 10%.

Documents

From /Applications/Microsoft PowerPoint.app/Contents/Info.plist CFBundleDocumentTypes (Editor = PowerPoint opens and saves; Viewer = opens only).

Format	PowerPoint	DeckCraft read	DeckCraft write	Fidelity / notes	Tested by
.pptx presentation	Editor	yes	yes	Broad (see below); corpus is decks we author, not measured against PowerPoint renders	crates/pptx/tests/corpus.rs, roundtrip.rs, sample.rs, malformed.rs, sniff.rs; opened in PowerPoint by hand 2026-10-06
.pptx presentation	Editor	yes	yes	Broad (see below); an owned corpus covers comments, links and actions, custom shows, rotated groups and placeholders that inherit from the layout. Embedded fonts and a corpus of decks from outside this repo are still open	crates/pptx/tests/roundtrip.rs, corpus_elements.rs, sample.rs, malformed.rs, sniff.rs; opened in PowerPoint by hand 2026-10-06
.pptx presentation	Editor	yes	yes	Broad (see below); an owned corpus covers text effects, autofit, columns, vertical and RTL text, tabs, line spacing, theme effects, gradient and pattern fills, bevels and connectors. A corpus of decks from outside this repo is still open	crates/pptx/tests/roundtrip.rs, corpus_style.rs, sample.rs, malformed.rs, sniff.rs; opened in PowerPoint by hand 2026-10-06
.pptx presentation	Editor	yes	yes	Broad (see below); never measured on real decks	crates/pptx/tests/roundtrip.rs, sample.rs, malformed.rs, sniff.rs (30 tests), corpus_media.rs; opened in PowerPoint by hand 2026-10-06
.potx template	Editor	yes (as a presentation)	no: written with the .pptx content type	file.saveTemplate is Save As under another name	none
.ppsx slide show	Editor	yes (as a presentation)	no: written as .pptx content	Doesn't start in show mode	none
.pptm / .potm / .ppsm macro-enabled	Editor	no	no	Should open and keep vbaProject.bin without running it	none
.ppt / .pot / .pps 97–2003 binary	Editor	no	no	Owner decision; import only would be enough	none
.odp OpenDocument	Editor	no	no		none
.thmx Office theme	Viewer	no	no	Browse for themes is a P2 row	none
.deckcraft native (zip + JSON)	n/a	yes (also .slidecraft)	yes	Lossless for the DeckCraft model, forward compatible	crates/format tests
PDF	export	no	yes	Slides, notes pages, handouts (1–9); real-text layer with embedded subsets, links, bookmarks. Slide artwork is a raster image at print resolution, not vector	crates/pdf tests
Outline .rtf / .txt	export (RTF), import (outline)	.txt outline; .md as Markdown (headings are slides, list items bullets) (slide.fromOutline)	.txt outline	No RTF	engine tests
PNG / JPEG slide images	export	n/a	yes (file.export, deckcraft-cli render)	Matches the editor's renderer	render tests
TIFF / BMP / GIF slide images	export	n/a	no	Easy (the image crate writes them)	none
Animated GIF of the deck	export	n/a	no		none
MP4 / MOV video of the deck	export	n/a	no	Needs timeline render + H.264 encode	none
Print	yes	n/a	no	PR #66 (browser) open	none

Pictures and media inside decks

Kind	PowerPoint	DeckCraft	Notes
PNG, JPEG, GIF (animated), BMP, TIFF, WebP	yes	yes	image 0.25; animated GIFs play since #39
SVG	yes (with PNG fallback)	no	The PNG fallback shows; SVG files can't be inserted
EMF / WMF	yes	partial	Drawn as vectors (paths, pens, pattern and hatch brushes, bitmaps, text in the document's fonts with the file's character advances). Rectangle clip regions (INTERSECTCLIPRECT, EXCLUDECLIPRECT, EXTSELECTCLIPRGN) limit later drawing. EMF+ only pictures play every EMF+ drawing record (brushes incl. gradients and textures, pens, paths, curves, images, strings, transforms, clipping; see crates/metafile/src/emfplus.rs for the few exceptions). Legacy OLE objects (VML preview) and ActiveX controls show their pictures
HEIC	yes (macOS)	no
Audio: MP3, AAC/M4A, ALAC, WAV, AIFF, CAF, FLAC, Ogg Vorbis, Opus	yes (Ogg/Opus partly)	yes	Pure-Rust decoders in crates/media, crates/opus
WMA	yes (Windows)	embedded, not playable
Video: H.264, HEVC in MP4/MOV	yes	yes	Pure-Rust, software decode
Video: VP9, AV1 in WebM/MKV	partly (OS codecs)	yes	Ahead of PowerPoint for Mac
WMV	yes (Windows)	embedded, not playable
Online video (YouTube embeds)	yes	no	Cloud feature
Embedded OLE objects	yes	kept on round trip (opaque), not insertable or editable	ShapeKind::Opaque
3-D models (.glb)	yes	no
Embedded fonts	yes	yes	p:embeddedFontLst read and written. TrueType, OpenType and Embedded OpenType faces are used to draw; MicroType Express subsets are kept and written back, not drawn
3-D models (.glb)	yes	kept	The model part round-trips (p:contentPart, including an mc:AlternateContent choice and its fallback picture). Not drawn as a mesh and not inserted from the ribbon
Embedded fonts	yes	no	p:embeddedFontLst ignored

PPTX coverage (PresentationML / DrawingML)

What crates/pptx reads and writes, from ECMA-376. "Kept" means the XML is preserved untouched for the round trip even though DeckCraft doesn't model it.

Part / feature	Read	Write	Notes
OPC package, content types, relationships	yes	yes	Content types found anywhere in the zip (#19); zip bombs capped; relationship cycles bounded
Presentation, slide size, sections (p14), custom shows	yes	yes
Slide masters, layouts, placeholders and inheritance	yes	yes
Themes: colour, font (Latin/EA/CS), effect schemes, background styles	yes	yes	Unknown theme parts kept
Notes slides and notes master	yes	yes	Header, footer, date and slide-number text on the notes master is kept. No notes-master editing view
Handout master	no	no
Shapes: preset geometry (~180 presets), custom geometry, groups, connectors	yes	yes	Presets re-derived in crates/geom/src/preset.rs (and preset/extra.rs). Outlines, dashes, arrowheads and ink inside a group, and text, keep their size in points whatever the group's child-coordinate scale (#233).
Fills: solid, gradient, picture (stretch/tile/crop), pattern, group	yes	yes
Lines: dash, compound, caps, joins, arrowheads	yes	yes
Effects: shadow, glow, soft edges, reflection	yes	yes
3-D: scene3d, sp3d	kept	kept	Not rendered
Text: runs, paragraphs, bullets, numbering, levels, autofit, columns, vertical, RTL, script fonts, fields, hyperlinks	yes	yes	Round-trip tests incl. justLow, date fields and paragraph defRPr (the defaults a placeholder's runs inherit, including a link). A click or hover action keeps its sound, endSnd, and a custom show's "Show and return"
Effects: shadow, glow, soft edges, reflection	yes	yes	On a run, inner shadow, reflection and soft edges are kept along with the outer shadow and glow
3-D: scene3d, sp3d	kept	kept	A bevel preset with no sp3d of its own is written back on shapes and theme effect styles. Bevels, cameras and face lighting draw approximately; extrusion does not
Text: runs, paragraphs, bullets, numbering, levels, autofit, columns, vertical, RTL, script fonts, fields, hyperlinks	yes	yes	Round-trip tests incl. justLow, date fields, gradient and outline on a run, autofit, columns, vertical and RTL text, tab stops and line spacing (corpus_style.rs)
Text warp (prstTxWarp)	yes	yes	All 40 presets rendered (crates/geom/src/warp.rs); adjust values (avLst) round-trip
Pictures with crop, recolour, duotone, alpha, luminance	yes	yes
Tables with styles	yes	yes	Merges and both diagonal borders round-trip
Charts (c:chartSpace)	yes	yes	Original XML kept in Chart.raw. Trendlines (type, order or period, forecast, intercept, equation and R²) are read, written and drawn. A combo chart's secondary value axis is read and is not written back when the chart is rebuilt
Charts (cx: chartex: waterfall, funnel, treemap, sunburst, histogram, Pareto, box)	yes	yes	Unchanged parts kept; edited and new ones written from the model with a plain-chart fallback. Treemap and sunburst hierarchy levels kept; region maps kept, drawn as tiles (no map geometry)
SmartArt (dgm)	drawing part only, as a group; text laid out on its dsp:txXfrm rectangle	as shapes	Diagram data model lost on save
SmartArt (dgm)	drawing part only, as a group	as shapes	Diagram data model lost on save. A diagram with no relationship parts keeps its XML; the drawing and data parts are still dropped (#203)
Equations (OMML, a14:m)	no	no	PR #55 open
Audio / video (p14:media, trim, fades, bookmarks)	yes	partly	Playback options lost on save (#74)
Ink (contentPart)	yes	as a group of freeform lines	PowerPoint sees shapes, not ink
Transitions incl. p14/p15 (Vortex, Morph…)	all 48	all 48	every_transition_kind_round_trips
Animations: timing tree, build paragraphs, triggers, motion paths	yes (flattened to the Animation Pane list)	yes (rebuilt)	every_animation_effect_survives; repeat, triggers and bounce end kept; rewind lost (#77)
Comments: legacy	yes	yes
Comments: modern threaded (p188)	yes	yes	Written next to the flattened legacy part; replies and resolved state round-trip (threads_and_resolved_round_trip)
Unknown slide-level elements (graphicFrame OLE, extensions, mc:AlternateContent)	kept	kept	Rendered as a labelled placeholder with the preview picture when present
Tags, custom XML, VBA	no / no / no
Embedded fonts	yes	yes	MicroType Express subsets kept, not drawn
Encryption (password to open)	no	no

What would move the PPTX number

1. A larger owned corpus (corporate templates, SmartArt, chartex charts, EMF, embedded fonts, every transition and animation) in a corpus repo. crates/pptx/tests/corpus.rs already checks open → save → reopen (parts and text) for decks we author. Still needed: render checks and a PowerPoint reference render for each (owner runs PowerPoint).
2. The round-trip losses above (#70, #74, #77).
3. SVG rendering. EMF+ records inside EMF/WMF are still not drawn.

Revision history

Date	Change	Summary
2026-10-12	minor	SmartArt import lays each shape's text out on its dsp:txXfrm text rectangle instead of the shape box
2026-10-13	minor	EMF/WMF rectangle clip regions limit later drawing; EMF+ records remain
2026-10-13	minor	Embedded fonts read and written; TrueType, OpenType and Embedded OpenType faces drawn
2026-10-13	minor	Owned corpus round-trip (parts and text). Notes-master header, footer, date and slide-number text is written back
2026-10-13	minor	Owned corpus for comments, links and actions, custom shows, rotated groups and inherited placeholders. Paragraph defRPr and action sounds (including custom-show return) survive a save
2026-10-13	minor	Owned corpus for text effects, body layout, theme effects, fills, bevels and connectors. A run's inner shadow, reflection and soft edge, and a bevel preset with no kept 3-D XML, survive a save
2026-10-14	minor	3-D models (.glb) round-trip, including an alternate-content fallback picture; animation bounce end is read and written (corpus_media.rs)
2026-10-14	minor	Chart trendlines are drawn (linear, exponential, logarithmic, polynomial, power, moving average, forecast, equation and R²)
2026-10-14	minor	Chart trendlines round-trip (corpus_charts.rs); merges, diagonal borders, columns, autofit, vertical text and WordArt warp are in that slice
2026-10-12	minor	EMF/WMF text and pattern brushes drawn; OLE (VML) and ActiveX previews read
2026-10-12	minor	Text warps rendered; their adjust values read and written
2026-10-12	trivial	Groups with a small legacy child coordinate space draw outlines, dashes, arrowheads and ink at their own width (#233)
2026-10-10	major	Created from PowerPoint 16.113.4's CFBundleDocumentTypes, crates/pptx reader/writer and tests, and the open round-trip issues
2026-10-13	minor	Comments: the writer emits the modern threaded part (p188) next to the flattened legacy one; the reader prefers the modern part and scales its EMU positions (#70)