Add color font palette support and improve variable font robustness by mattleibow · Pull Request #3742 · mono/SkiaSharp

mattleibow · 2026-04-25T17:02:38Z

Summary

Builds on top of the variable font support merged in #3703. Adds color font palette APIs (Skia + HarfBuzz), improves Span method robustness, and significantly expands test coverage.

Companion skia PR: mono/skia#197

Color Font Palette Support

SkiaSharp

SKTypeface.Clone(int paletteIndex) — clone with a specific palette
SKTypeface.Clone(SKFontArguments) — clone with palette index, overrides, variation position, and collection index
SKFontArguments.PaletteIndex / PaletteOverrides — ref struct properties for palette configuration
SKFontPaletteOverride struct — override individual palette color entries

HarfBuzzSharp

Face.HasPalettes / PaletteCount — query color font palette support
Face.GetPaletteColors(int) / GetPaletteColors(int, Span<uint>) — retrieve palette color entries
Face.GetPaletteFlags(int) / GetPaletteNameId(int) / GetPaletteColorNameId(int) — palette metadata
Face.HasColorLayers / HasColorPng / HasColorSvg — color font capability detection

C API (skia submodule)

sk_fontarguments_palette_override_t struct
sk_typeface_clone_with_arguments extended with paletteIndex, paletteOverrides, paletteOverrideCount
DEF_MAP + static_assert for Palette::Override

Span Method Robustness

Skia undersized buffer fix: GetVariationDesignParameters(Span) and GetVariationDesignPosition(Span) now handle Skia's all-or-nothing native semantics — if the buffer is too small, they retry with a pooled buffer (ArrayPool) and copy what fits, returning the actual written count
Empty span early return: both methods return 0 immediately for empty spans, avoiding unnecessary native calls and pool allocations
HarfBuzz Font.GetVariationCoordsNormalized(Span): fixed to return written count instead of total length when buffer is undersized

Bug Fix

SKTypeface.ContainsGlyphs(ReadOnlySpan<byte>, SKTextEncoding): fixed pre-existing infinite recursion (called itself instead of GetFont().ContainsGlyphs(...)) that caused StackOverflowException

Validation & Tests

All Span APIs tested across 5 buffer scenarios with exact assertions:

Scenario	Coverage
Negative index	Throws `ArgumentOutOfRangeException`
Empty (0-size) span	Returns 0
Undersized span	Fills what fits, returns written count
Exact-size span	Fills all, matches array property
Oversized span	Fills total, returns total
Static font	Returns 0 or -1 (platform-dependent)

New test coverage

12 palette API tests (colors, flags, name IDs, different palettes, negative indices)
HasColorPng / HasColorSvg false-path tests
CloneWithPaletteOverride / CloneWithDifferentPaletteIndex / CloneWithNegativePaletteIndexThrows
ContainsGlyphsWithByteSpanDoesNotStackOverflow
Undersized buffer tests for all 6 Span APIs (Skia + HarfBuzz)
InterVariable.ttf added for multi-axis testing

Gallery Sample

Color Fonts sample: Nabla font (Google Fonts, COLRv1) with 7 palette picker, weight/YTRA sliders, demonstrates Clone(SKFontArguments) with palette + variation axes

Files Changed

Area	Files
C# bindings	`SKTypeface.cs`, `SKFontArguments.cs`, `Face.cs`, `Font.cs`
Generated	`SkiaApi.generated.cs`, `libSkiaSharp.json`
C API	`sk_typeface.h`, `sk_typeface.cpp`, `sk_types_priv.h`, `sk_structs.cpp`
Tests	`SKTypefaceTest.cs`, `HBFaceTest.cs`, `HBFontTest.cs`
Samples	`ColorFontSample.cs`, `Nabla.ttf`
Test fonts	`InterVariable.ttf`, `test_glyphs-COLRv1.ttf`

Native layer (mono/skia submodule): - C API: sk_typeface_get_variation_design_position, sk_typeface_get_variation_design_parameters, sk_typeface_clone_with_arguments - New structs: sk_fontarguments_variation_axis_t, sk_fontarguments_variation_position_coordinate_t SkiaSharp managed bindings: - SKTypeface: GetVariationDesignParameters, GetVariationDesignPosition, Clone - SKFontVariationTag: Make("wght") / GetName(tag) helper - TagName property on SKFontVariationAxis and SKFontVariationDesignPositionCoordinate - Generated P/Invoke bindings and struct type mappings in libSkiaSharp.json HarfBuzzSharp managed bindings: - Face: HasVariationData, axis queries, named instance enumeration - Font: SetVariations, Set/GetVarCoords, SetVarNamedInstance - P/Invoke bindings for hb-ot-var.h (removed from exclude list) Tests: - HBFaceTest, HBFontTest, SKTypefaceTest, SKVariableFontRenderingTest Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

- Face: validate instanceIndex >= 0 on named instance methods - Face: explicit (int) cast on uint array lengths - Font: validate instanceIndex >= 0 on SetVarNamedInstance - Tests: dispose Blob in CreateVariableFace/CreateVariableFontPair helpers Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Interactive demo that showcases the new variable font APIs: - Weight axis slider (100–900) with real-time text rendering - Optical size axis slider (14–32) - Weight spectrum showing all 9 standard weights - Uses Inter Variable font (SIL OFL license, 2 axes: wght, opsz) Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Default parameters break ABI stability. Split into two overloads: - Clone(position) delegates to Clone(position, 0) - Clone(position, collectionIndex) contains the implementation Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Incorporates libpng 1.6.58, libexpat 2.7.5, and stream move int32 fix. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…pport # Conflicts: # binding/SkiaSharp/SkiaApi.generated.cs

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Face: - GetVariationAxisCount() → VariationAxisCount property - GetNamedInstanceCount() → NamedInstanceCount property - Add GetVariationAxisInfos(Span<>) overload - Add GetNamedInstanceDesignCoordsCount() - Add GetNamedInstanceDesignCoords(int, Span<float>) overload Font: - Rename SetVarCoordsDesign → SetVariationCoordsDesign - Rename SetVarCoordsNormalized → SetVariationCoordsNormalized - Rename SetVarNamedInstance → SetVariationNamedInstance - GetVarCoordsNormalized() → VariationCoordsNormalized property - Add GetVariationCoordsNormalized(Span<int>) overload Tests: add span-vs-array equivalence tests for all overloads. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Face tests: - VariationAxisCount matches GetVariationAxisInfos().Length - Span overload with oversized buffer - NamedInstanceCount asserts > 0 (Distortable.ttf has 3 instances) - DesignCoordsCount matches AxisCount (per HB docs, return value) - DesignCoords array length matches count - Span vs array equivalence for design coords - All named instances have non-empty design coords - SubfamilyNameId returns valid name ID - PostScriptNameId does not throw - Negative index throws for all 5 instance methods Font tests: - Span GetVariationCoordsNormalized returns total length with empty buffer - SetVariationCoordsDesign affects normalized coords - Negative index throws for SetVariationNamedInstance - Span returns 0 for static font Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Follows existing HarfBuzzSharp convention where parameterless array-returning getters are properties (Tables, GlyphInfos, GlyphPositions, VariationCoordsNormalized). The Span<> overload remains a method since it takes a parameter. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

SKFontVariationTag was a static helper class that didn't correspond to any Skia type. Replace it with SKFourByteTag, a proper struct matching Skia's SkFourByteTag (uint32_t) with the same bit layout. SKFourByteTag provides: - Parse(string) for creating tags from strings like "wght" - ToString() for converting back to four-character strings - Implicit uint conversion (matches how Skia uses uint32_t) - IEquatable<T>, ==, != operators - char constructor matching SkSetFourByteTag(a,b,c,d) Follows the same pattern as HarfBuzzSharp.Tag but in the SkiaSharp namespace, wrapping Skia's native type rather than HarfBuzz's. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

The primary type in this file is now SKFourByteTag. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

The generator's member mapping only supports name remapping (string), not type overrides, so the generated struct fields stay as UInt32. With implicit uint <-> SKFourByteTag conversion, users cast explicitly: SKFourByteTag tag = axis.Tag; string name = tag.ToString(); Revert the libSkiaSharp.json change that tried object-style members. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

- Add sk_fourbytetag_t → SKFourByteTag mapping in libSkiaSharp.json - Regenerate SkiaApi.generated.cs: SKFontVariationAxis.Tag and SKFontVariationDesignPositionCoordinate.Axis are now SKFourByteTag - axis.Tag.ToString() now returns "wght" directly (no cast needed) - Update tests to use SKFourByteTag.Parse instead of raw hex Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Doc comments are inserted via a localized repo process, not manually. Fix Assert.NotEqual type inference after Tag became SKFourByteTag. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Pure value type with no reference fields — nullable context is fine. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…and Span overloads Rename: - SKFontVariationDesignPositionCoordinate → SKFontVariationPositionCoordinate (matches C++ SkFontArguments::VariationPosition::Coordinate — no 'Design' in the struct name; 'Design' belongs in the method names only) Add count properties for span-based usage: - VariationDesignParameterCount - VariationDesignPositionCount Clone now takes ReadOnlySpan instead of array. Tests: span vs property equivalence, static font span returns, ReadOnlySpan clone. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Skia: - Add sk_fontarguments_palette_override_t C struct - Extend sk_typeface_clone_with_arguments with palette parameters - Add SKFontPaletteOverride generated struct - Add Clone overload with paletteIndex + palette overrides HarfBuzz Face: - HasPalettes, PaletteCount properties - GetPaletteColors() + Span<uint> overload - GetPaletteFlags(), GetPaletteNameId(), GetPaletteColorNameId() - HasColorLayers, HasColorPng, HasColorSvg properties Tests (18 new): - Color font test_glyphs-COLRv1.ttf (21KB, 3 palettes, 14 entries) - Palette queries: count, colors, flags, name IDs - Span vs array equivalence for palette colors - Different palettes have different colors - Negative index validation for all palette methods - SKTypeface Clone with palette override and palette index Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Demonstrates COLRv1 color font palette selection using the test glyph font (3 palettes, 14 color entries). Shows: - Palette index slider to switch between built-in palettes - Color swatch display for current palette entries - Glyph picker for different Unicode codepoints - Text size slider Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

API surface improvements: - SKFontVariationTag → SKFourByteTag struct (matches Skia's SkFourByteTag) - SKFontVariationDesignPositionCoordinate → SKFontVariationPositionCoordinate - Properties instead of Get*() for parameterless array getters - Span<T> and ReadOnlySpan<T> overloads for all APIs - Count properties (VariationDesignParameterCount, VariationDesignPositionCount) - Overloads instead of default parameters (ABI stability) - File-scoped namespaces in new files - Consistent 'Variation' naming (not 'Var') in HarfBuzz C API cleanup (skia submodule): - sk_fourbytetag_t typedef, DEF_MAP for converters - static_assert in sk_structs.cpp - As*/To* helpers in sk_types_priv.h HarfBuzz Face: - VariationAxisCount, NamedInstanceCount → properties - VariationAxisInfos → property - Span overloads + GetNamedInstanceDesignCoordsCount - Fixed return-value semantics for hb_ot_var_named_instance_get_design_coords HarfBuzz Font: - Renamed SetVar* → SetVariation* for consistency - VariationCoordsNormalized property + Span overload Tests: comprehensive coverage for all new APIs (131 tests). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

github-actions · 2026-04-25T17:02:45Z

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Step 2 — Add the local NuGet source

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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

github-actions · 2026-04-25T17:17:11Z

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SKFontArguments is a ref struct with ReadOnlySpan properties for allocation-free usage. Clone API: - Clone(ReadOnlySpan<Position>) — variable font shortcut - Clone(int paletteIndex) — color palette shortcut - Clone(SKFontArguments) — full control (position, collection, palette, overrides) Removes the noisy (span, int, int, span) overload. Simplifies ColorFontSample from Clone(emptySpan, 0, idx, emptySpan) to Clone(idx). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Incorporates sk_fontmgr_legacy_create_typeface C API fix (#198). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Copilot

Pull request overview

Adds OpenType variable-font robustness and introduces color font palette support across SkiaSharp + HarfBuzzSharp, with new samples and expanded test coverage.

Changes:

Add SKTypeface palette cloning support via SKFontArguments (palette index + overrides) and a new SKFontPaletteOverride interop struct.
Add HarfBuzzSharp Face APIs for querying palettes/colors/flags/name IDs and color table presence.
Expand tests for undersized Span buffer behavior and add a new Gallery sample for color palettes (Nabla).

Reviewed changes

Copilot reviewed 12 out of 16 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tests/Tests/SkiaSharp/SKTypefaceTest.cs	Adds tests for undersized Span buffers and palette clone APIs.
tests/Tests/HarfBuzzSharp/HBFontTest.cs	Tightens variation tests and aligns Span semantics with “written count”.
tests/Tests/HarfBuzzSharp/HBFaceTest.cs	Adds palette/color font API tests (colors, flags, IDs, negative index checks).
tests/Content/fonts/test_glyphs-COLRv1.ttf	Adds a COLRv1/CPAL test font for palette coverage.
samples/Gallery/Shared/Samples/ColorFontSample.cs	New Gallery sample demonstrating palette selection and preview grid.
samples/Gallery/Shared/SampleMedia.cs	Exposes embedded Nabla + COLRv1 test glyphs fonts to samples.
samples/Gallery/Shared/Media/COLRv1-TestGlyphs.ttf	Adds COLRv1 test font for sample media.
binding/libSkiaSharp.json	Maps new native palette override struct to managed type.
binding/SkiaSharp/SkiaApi.generated.cs	Updates native clone signature + generates `SKFontPaletteOverride`.
binding/SkiaSharp/SKTypeface.cs	Implements palette clone overload and Span “undersized buffer” behavior.
binding/SkiaSharp/SKFontArguments.cs	Extends arguments with `PaletteIndex` and `PaletteOverrides`.
binding/HarfBuzzSharp/Font.cs	Fixes Span getter to return written count for normalized coords.
binding/HarfBuzzSharp/Face.cs	Adds palette/color-table query APIs and palette color retrieval.

Fix pre-existing bug: SKTypeface.ContainsGlyphs(ReadOnlySpan<byte>, SKTextEncoding) called itself instead of GetFont().ContainsGlyphs(), causing StackOverflowException. Add tests: - ContainsGlyphsWithByteSpanDoesNotStackOverflow (confirms fix) - HasColorPngIsFalseForStaticFont - HasColorSvgIsFalseForStaticFont Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

- Empty span (length 0) now returns 0 immediately without calling native or allocating from the pool - Clone(int paletteIndex) now throws ArgumentOutOfRangeException for negative indices, matching HarfBuzz Face palette methods - Add test: CloneWithNegativePaletteIndexThrows Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Add missing tests to ensure every Span API is tested for: empty (0), undersized, exact, and oversized buffers. HarfBuzz Face: - GetVariationAxisInfos: add empty buffer test - GetNamedInstanceDesignCoords: add empty and oversized tests - GetPaletteColors: add empty buffer test HarfBuzz Font: - GetVariationCoordsNormalized: add oversized test Skia SKTypeface: - GetVariationDesignParameters: add oversized test - GetVariationDesignPosition: add oversized test Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

COLRv1-TestGlyphs.ttf and its SampleMedia property were never used by any sample. The font remains in tests/Content/fonts/ where it's used by unit tests. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

https://mono.github.io/SkiaSharp/staging/3742/

Copilot

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds variable font robustness plus color font palette APIs across SkiaSharp/HarfBuzzSharp, with expanded tests and a new gallery sample.

Changes:

Fixes/extends variable font Span APIs (undersized/oversized/empty buffers) and related regression tests.
Introduces color font palette support (palette counts/flags/name IDs/colors, palette overrides, palette-aware typeface cloning).
Adds a new Color Fonts gallery sample and updates embedded media.

Reviewed changes

Copilot reviewed 12 out of 15 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tests/Tests/SkiaSharp/SKTypefaceTest.cs	Adds regression + buffer-sizing tests for variable fonts and palette cloning.
tests/Tests/HarfBuzzSharp/HBFontTest.cs	Tightens variation tests and adds undersized-buffer coverage.
tests/Tests/HarfBuzzSharp/HBFaceTest.cs	Adds extensive palette/color font API tests.
samples/Gallery/Shared/Samples/ColorFontSample.cs	New interactive sample demonstrating palette selection rendering.
samples/Gallery/Shared/SampleMedia.cs	Adds Nabla font stream for the new sample.
externals/skia	Updates Skia submodule for new C APIs.
binding/libSkiaSharp.json	Maps new native palette override struct to managed type.
binding/SkiaSharp/SkiaApi.generated.cs	Updates clone_with_arguments P/Invoke signature + adds SKFontPaletteOverride struct.
binding/SkiaSharp/SKTypeface.cs	Fixes recursion bug, improves Span behavior, and adds palette cloning/args.
binding/SkiaSharp/SKFontArguments.cs	Extends font arguments with palette index and overrides.
binding/HarfBuzzSharp/Font.cs	Changes Span getter semantics to return written count.
binding/HarfBuzzSharp/Face.cs	Adds HarfBuzz color palette APIs (counts, colors, flags, name IDs, formats).

Add color font palette support to C API (#197) Requires: mono/SkiaSharp#3742 Extends the variable font C API (merged in #185) with color palette support, enabling SkiaSharp to clone typefaces with specific palette selections and per-color overrides for COLRv1/COLR fonts. New C API surface: * sk_fontarguments_palette_override_t — struct mapping to SkFontArguments::Palette::Override (index + color) * sk_typeface_clone_with_arguments — extended from 4 to 7 parameters, adding paletteIndex, paletteOverrides, and paletteOverrideCount Supporting changes: * DEF_MAP for Palette::Override (reinterpret_cast, layout-compatible) * static_assert in sk_structs.cpp for ABI verification * AsSkFontArguments helper updated to call setPalette() Co-authored-by: Ramez Gerges <ramezragaa@proton.me> Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

https://mono.github.io/SkiaSharp/staging/3742/

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

https://mono.github.io/SkiaSharp/staging/3742/

Pulls origin/skiasharp commit b9b89f23a5 ("Add color font palette support to C API") into our dev/update-skia-147 work tree. The new sk_typeface_clone_with_arguments signature gains paletteIndex + palette-override array parameters; AsSkFontArguments grows to match. Required by mono/skiasharp PR mono#3742 (origin/main HEAD), which adds the corresponding managed wrappers. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Re-runs the SkiaSharp generator against the merged submodule head so the bindings reflect the union of: - origin/main's color font palette additions (sk_typeface_clone_with_arguments new signature with paletteIndex / palette-override array, plus the sk_fontarguments_palette_override_t struct, from PR mono#3742 on the managed side and PR mono#197 on the C-API side), - our existing m147 surface carries. HarfBuzzApi.generated.cs is intentionally not regenerated here — see the prior "Regenerate SkiaApi.generated.cs" commit for rationale (generator picks up extra HB 7.0+ callback APIs that have no hand-written DelegateProxies companion in this repo). During the rebase onto origin/main I took --ours on the SkiaApi.generated.cs conflict to keep the rebase moving; this is that regeneration. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

ramezgerges and others added 21 commits April 22, 2026 17:53

Update skia submodule: merge origin/skiasharp

b24f0b7

Incorporates libpng 1.6.58, libexpat 2.7.5, and stream move int32 fix. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Merge remote-tracking branch 'origin/main' into 001-variable-fonts-su…

ec65fe0

…pport # Conflicts: # binding/SkiaSharp/SkiaApi.generated.cs

Use file-scoped namespaces in new files

3e1ea36

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Rename SKFontVariationAxis.cs to SKFourByteTag.cs

6e23d92

The primary type in this file is now SKFourByteTag. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Update skia submodule: DEF_MAP and static_assert cleanup

efb7139

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Remove XML doc comments and fix test compilation

324305d

Doc comments are inserted via a localized repo process, not manually. Fix Assert.NotEqual type inference after Tag became SKFourByteTag. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Remove unnecessary #nullable disable from SKFourByteTag

5f84f1d

Pure value type with no reference fields — nullable context is fine. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

github-project-automation Bot added this to SkiaSharp Backlog Apr 25, 2026

Add PR screenshots for variable font comparison

cf45dc9

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

github-actions Bot pushed a commit that referenced this pull request Apr 25, 2026

Deploy staging docs for PR #3742

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github-actions Bot pushed a commit that referenced this pull request Apr 25, 2026

Deploy staging docs for PR #3742

507fba0

mattleibow and others added 2 commits April 25, 2026 20:52

Remove screenshots from repo (permalinked via SHA)

af42511

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Update skia submodule: merge origin/skiasharp

4b93266

Incorporates sk_fontmgr_legacy_create_typeface C API fix (#198). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Copilot AI reviewed Apr 26, 2026

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Comment thread binding/SkiaSharp/SKTypeface.cs

Comment thread samples/Gallery/Shared/Samples/ColorFontSample.cs

Comment thread samples/Gallery/Shared/Samples/ColorFontSample.cs

Comment thread binding/SkiaSharp/SKTypeface.cs

Comment thread binding/SkiaSharp/SKTypeface.cs

mattleibow and others added 3 commits April 26, 2026 15:31

mattleibow force-pushed the dev/font-enhancements branch from 80170a5 to 323d3f7 Compare April 26, 2026 13:42

github-actions Bot pushed a commit that referenced this pull request Apr 26, 2026

Deploy staging docs for PR #3742

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https://mono.github.io/SkiaSharp/staging/3742/

mattleibow requested a review from Copilot April 26, 2026 16:14

Copilot started reviewing on behalf of mattleibow April 26, 2026 16:15 View session

Merge remote-tracking branch 'origin/main' into dev/font-enhancements

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Comment thread tests/Tests/SkiaSharp/SKTypefaceTest.cs

Comment thread binding/HarfBuzzSharp/Face.cs

Comment thread binding/HarfBuzzSharp/Font.cs

Comment thread samples/Gallery/Shared/Samples/ColorFontSample.cs

Comment thread samples/Gallery/Shared/Samples/ColorFontSample.cs

mattleibow marked this pull request as ready for review April 26, 2026 16:21

mattleibow changed the title ~~Variable font and color palette support~~ Add color font palette support and improve variable font robustness Apr 26, 2026

mattleibow mentioned this pull request Apr 26, 2026

Add color font palette support to C API mono/skia#197

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github-actions Bot pushed a commit that referenced this pull request Apr 26, 2026

Deploy staging docs for PR #3742

70c3a5d

https://mono.github.io/SkiaSharp/staging/3742/

Update skia submodule to include palette C API (#197)

1a73f53

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

github-actions Bot pushed a commit that referenced this pull request Apr 26, 2026

Deploy staging docs for PR #3742

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https://mono.github.io/SkiaSharp/staging/3742/

mattleibow merged commit 9dba444 into main Apr 26, 2026
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mattleibow deleted the dev/font-enhancements branch April 26, 2026 19:12

github-project-automation Bot moved this to Done in SkiaSharp Backlog Apr 26, 2026

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Remove staging docs for PR #3742

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mattleibow mentioned this pull request Apr 28, 2026

fix: reuse same PR for release notes workflow #3782

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[docs] Add release notes for upcoming version 4.147.0 #3784

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This was referenced May 8, 2026

[FEATURE] Expose additional API for variable font support #2397

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[FEATURE] Variable fonts support, shaping with opentype features opt-in #2318

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Update HarfBuzzSharp binding #3490

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mattleibow added this to the 4.x Preview 1 milestone May 19, 2026

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Add color font palette support and improve variable font robustness#3742

Add color font palette support and improve variable font robustness#3742
mattleibow merged 43 commits into
mainfrom
dev/font-enhancements

mattleibow commented Apr 25, 2026 •

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mattleibow commented Apr 25, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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Summary

Color Font Palette Support

SkiaSharp

HarfBuzzSharp

C API (skia submodule)

Span Method Robustness

Bug Fix

Validation & Tests

New test coverage

Gallery Sample

Files Changed

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github-actions Bot commented Apr 25, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

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📦 Try the packages from this PR

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mattleibow commented Apr 25, 2026 •

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github-actions Bot commented Apr 25, 2026 •

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