dart_pdf_editor_flutter_gpu 0.3.4

Opt-in Impeller flutter_gpu tile backend for dart_pdf_editor.

Changelog

0.3.4

• Outline unembedded standard-14 text from the bundled metric-compatible TeX Gyre faces where dart_pdf_editor_assets supplies them, so the accelerated backend draws the same glyphs, in the same places, as the Canvas renderer. The platform font catalogue is still used when those assets are absent, and a face that is still loading declines the run rather than outlining one Canvas would not draw.

0.3.3

• Stop stretching substituted glyphs across their character spacing in the outliner, matching the raster path.

0.3.2

• Align dependency constraints with the dart-pdf 4.3.0 package suite.

0.3.1

• Report full-page raster warm-up support to dart_pdf_editor via the new supportsFullPageRasterWarmUp backend getter, so document raster warming can use the GPU route where it is available.
• Make deterministic GPU buffer reuse stable under benchmarking.
• Require the dart-pdf 4.2.0 package suite. No public constructor or rendering entry point was removed.

0.3.0

• Greatly expand exact retained-GPU coverage for blends, transparency groups, soft masks, gradients, images, stroked text, overprint, and knockout groups, while preserving the Canvas fallback for unsupported or inexact scenes.
• Reduce GPU allocation and submission overhead with completion-fenced buffer and attachment pools, compact transient arenas, scene-level texture leases, retained bindings, and bounded advanced-blend source targets.
• Import compatible platform-decoded image textures directly, keep mipmapped fallback pixels only when needed, and accelerate MRC JPEG 2000 rendering on supported Apple devices.
• Add proactive pipeline and live-scene warm-up, exact high-resolution colourant retries, off-crop command culling, and deterministic route and performance diagnostics.
• Keep dense CAD linework conservative at subpixel scale, retain more exact hairlines and clipped vector content, and fix lifetime hazards around in-flight GPU resources.
• Require the dart-pdf 4.1.0 package suite. No existing public constructor or rendering entry point was removed.

0.2.0

• Require the dart-pdf 4.0.0 suite and its expanded tile-backend warm-up and transparency interfaces.

• Run requested scene warm-up for route-change benchmarks, matching the viewer's idle-prepared production path while suppressing the unmatched timing marker when the Canvas base has no GPU session.

• Preserve per-paint Normal, Multiply, and Screen state inside isolated offscreen transparency groups.

• Retain ordinary images in single-paint and mixed vector/text transparency groups, reusing the scene texture cache and the exact offscreen group pass.

• Retain outlined text in single-paint and mixed vector transparency groups, including clipped isolated groups that require the exact offscreen tile pass for group alpha and outer blending.

• Retain exact macOS CJK substitutions for Songti, Heiti, Hiragino Sans, and Hiragino Mincho, including CFF outlines inside OpenType collections. Six additional PDF.js corpus pages now stay on the GPU, with a dedicated CJK same-host scenario.

• Render every PDF blend mode exactly with retained GPU destination sampling. Advanced modes use bounded ping-pong tile attachments; provably disjoint paints share one blend pass, while overlapping paints retain painter order. Oversized tiles and scenes that combine advanced blends with offscreen transparency groups keep the conservative Canvas fallback.

• Retain isolated knockout groups made entirely from vector fills. Later sibling shapes use exact source replacement only inside their retained path, while the group's alpha and outer blend remain a single offscreen composite.

• Retain isolated knockout groups containing a base fill and one vector-soft-masked fill, including clipped vector mask bounds.

• Render overlapping Normal paints in isolated transparency groups into a shader-readable tile attachment, then apply group alpha and outer blend once when sampling it into the page pass.

• Elide zero-alpha and zero-area transparency groups before GPU auditing; their composite alpha or form BBox clip makes all nested paints exact no-ops.

• Retain non-Normal transparency groups whose padded fill bounds are provably disjoint, preserving exact outer blending without an offscreen surface.

• Treat C1 controls as non-rendering glyph placements in the exact native outline seam, matching Flutter shaping while preserving their PDF advances.

• Retain stroke-only and fill-plus-stroke outline text, including page-space alpha and zero-width hairlines, by reusing the exact path stroke pipeline. Filled glyphs keep the analytic atlas while their stroke overlays in painter order.

• Retain ordinary filled text as six-vertex glyph quads backed by a scale-independent analytic curve atlas. The shader derives device scale per tile, eliminating repeated flattened outline fans across LoDs while exact stencil rendering remains the automatic fallback for unsupported glyphs.

• Add an exact substituted-text outline seam for the retained backend. Hosts can resolve their registered TrueType/TTC bytes directly, while the opt-in native adapter probes the standard platform substitution faces and declines any unavailable, complex-shaped, or unplaceable run. Add the same-host system-font route-change benchmark to the Metal CI matrix.

• Render zero-width PDF hairlines as exact one-device-pixel contours generated for each tile LoD, while retaining the flattened source path with the scene.

• Collapse isolated transparency groups containing one clipped vector fill or stroke into retained stencil geometry, preserving group alpha and the group's page blend mode without an intermediate texture; one-element knockout groups use the same exact path because they have no sibling elements to knock out. Alpha-one, normal-blend non-knockout groups can retain multiple ordered fills and strokes because source-over is associative.

• Render platform-decoded images with deferred /SMask companion surfaces on the GPU by caching both textures and combining them in the soft-mask shader.

• Combine a single vector fill with one opaque grayscale image soft mask in a retained stencil pass. Rectangular vector-mask fills, including alpha or luminosity /BC and linearized /TR, stay entirely in retained geometry.

• Render Multiply and Screen exactly with fixed-function blending over the backend's opaque page surface.

• Warm the nonzero stencil-cover render state used by retained fills, moving its first-use Metal compilation into the existing idle pipeline phase.

• Render tiled stencil images exactly using scene-scoped, hand-built mipmaps. Mip levels participate in the shared texture budget and cache identity, and worker-reconstructed tiling cells retain their decoded images.

• Warm every tile shader with a one-pixel idle submission, shared per Impeller context and MSAA mode, then compile and submit each live page's retained scene at one-pixel scale. Both passes wait for useful pixels plus a 750 ms quiet window, so first-use driver, geometry, and upload work does not land on the first deep-zoom tile or contend with immediate navigation. Proactive warm-up defaults to desktop; mobile stays on-demand unless the host opts in, avoiding a large idle context allocation on memory-constrained devices.

• Benchmark tiling-pattern and radial-shading pipeline warm-up, scene warm-up, first GPU tiles, and Canvas parity three times on the designated macOS Metal CI lane. PRs receive a main comparison with details collapsed beneath the headline, and retain the normalized trace as a downloadable artifact.

• Accelerate exact vector tiling cells, axial gradients (including embedded outline text), and nested-circle radial gradients while retaining explicit Canvas fallback for unsafe variants.

0.1.6

• Align the experimental Flutter GPU backend with the 3.8.0 package suite. No public GPU API changes since 0.1.5.

0.1.5

• Align the experimental Flutter GPU backend with the 3.7.0 package suite.

0.1.4

• Isolate pipelines, geometry buffers, and image textures by Flutter GPU context so native windows never reuse resources owned by another view.
• Keep image-texture leases alive until in-flight command buffers complete, preventing stale blocks or unrelated fragments after structural edits.
• Report context identities and switches in the backend diagnostics.

0.1.3

• Rebuild the packaged shader bundle with Flutter 3.47's impellerc so the runtime accepts the new bundle format.

0.1.2

• Support both the Flutter 3.44 and 3.47 flutter_gpu APIs after shader loading became asynchronous and draw vertex counts moved to draw.

0.1.1

• Fall back to the Canvas renderer for deferred image soft masks that the GPU backend cannot yet reproduce exactly, preserving correct output on Impeller.

0.1.0

• Render final GPU tile textures directly and admit one per repaint, avoiding deferred slab-to-tile texture-copy bursts. Track synchronous issue time and command-buffer completion latency, failures, and in-flight submissions.
• Render ordinary non-rectangular PDF clip stacks exactly with retained stencil geometry, including nested even-odd/nonzero clips and save/restore; rectangular clips keep the cheaper scissor path.
• Report compiled clip paths and per-tile clip-mask rebuilds in backend stats.
• Add an opt-in Impeller flutter_gpu backend for retained-scene LoD tiles.
• Retain geometry and byte-budgeted image textures across tile renders and combine supported image soft masks directly in the tile shader.
• Pack command-heavy CAD geometry into backend-wide reusable 16 MiB device buffers under a strict byte budget, releasing leases only after GPU work completes and falling back instead of overshooting the ceiling.
• Fall back to the Canvas backend for unsupported pages and expose a web stub that preserves the same host API.
• Expose JSON-safe diagnostics for the latest tile route, accepted/rejected/ active sessions, runtime fallbacks, compile/replay timings, cache pressure, uploads/readbacks, and live GPU resource leases.