0.9.0

🎉 Overview

v0.9.0 is a major update that includes significant performance improvements, API redesign, and the introduction of a more user-friendly Builder pattern.

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⚡ Performance Improvements

This release dramatically improves QR code generation speed and memory efficiency:

Performance for several data types.

Memory Allocation Reduction

• Redesigned QRCodeData implementation from List<BitArray> to 1D byte[] array (#233, #186)
• Used stackalloc for small datasets to reduce allocations (#236, #209, #212)
• Leveraged ArrayPool for large datasets (#228, #237)
• Reused temporary QRCode objects during mask pattern selection (#207, #234)
• Removed allocations during FinderPattern placement (#243)
• Reduced re-allocations when adding masks by including QuietZone in constructor (#252)

Algorithm Optimization

• Replaced LINQ linear search O(n) with lookup table O(1) (#173)
• Removed LINQ from hot paths (#184, #198, #202)
• Eliminated Reflection usage (MaskCode) (#191)
• Executed penalty calculations in a single pass (#231, #241)
• Optimized Penalty3 calculation with sliding window 11-bit masking (#232)
• Optimized QR code module placement with bitmask (#244)
• Pre-calculated mod/div for mask pattern selection (#248)
• Wrote multiple bits at once (#225)
• Single-pass text analysis with TextAnalyzer (#229)

Data Structure Improvements

• Changed QR Code data tables from instance to Lazy static, initializing once (#171)
• Changed Point & Rectangle from class to readonly record struct (#166)
• Made Vector2Slim immutable (#196)
• Changed CodewordBlock to readonly struct (#199)
• Replaced string format/version operations with uint/ushort (#208)

Other Optimizations

• Changed char array access to range check for Numeric/AlphaNumeric (#168, #169)
• Used StringBuilder with capacity (#172)
• Specified List capacity (#185)
• Faster ISO-8859-1 validation with range check (#180)
• Removed unnecessary modulo in Galois multiplication (#247)
• Removed temporary collections with collection expressions (#211)

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💥 Breaking Changes

API Changes

1. QrCode Class Deprecation and Migration to QRCodeImageBuilder

The QrCode class is now obsolete. Please use the new QRCodeImageBuilder instead. See detail #266

Before (Old API):

var qrCode = new QrCode(content, new Vector2Slim(512, 512), SKEncodedImageFormat.Png);
using (var output = new FileStream(path, FileMode.OpenOrCreate))
{
    qrCode.GenerateImage(output);
}

After (New API):

Simple QR code generation with static method:

var pngBytes = QRCodeImageBuilder.GetPngBytes(content);
File.WriteAllBytes(path, pngBytes);

Advanced usage with builder pattern:

using var stream = File.OpenWrite(path);
var pngBytes = new QRCodeImageBuilder(content)
    .WithSize(512, 512)
    .WithErrorCorrection(ECCLevel.H)
    .SaveTo(stream);

Related PRs: #265, #264

2. IDisposable Removal

• Removed IDisposable from QRCodeData (#214)
• Removed IDisposable from QRCodeRenderer and changed to static class (#216, #220)

Remove using statements for these classes if you were using them.

// 0.8.0 and before
using var qrCodeData = QRCodeGenerator.CreateQrCode("Hello, World!", ECCLevel.L);

// 0.9.0 and after
var qrCodeData = QRCodeGenerator.CreateQrCode("Hello, World!", ECCLevel.L);

// 0.8.0 and before
using var renderer = new QRCodeRenderer();
renderer.Render(...);

// 0.9.0 and after
QRCodeRenderer.Render(...);

3. Stricter Null Checking

QRCodeRenderer.Render now throws ArgumentNullException when null data is passed (#218)

4. IconData Namespace Move

IconData moved to SkiaSharp.QrCode.Image namespace (#239)

Update your using directives:

using SkiaSharp.QrCode.Image;

5. QuietZone Size Specification

QRCodeData(byte[] rawData) now accepts QuietZoneSize specification (#253)

Removed Features

• Removed forceUtf8 parameter (#177)
• Removed ISO-8859-2 encoding support (#178)
• Removed compression feature (#256)
• Removed Kanji encoding mode (#269)

Encoding Changes

• Fixed empty data encoding from Numeric to Byte (#240)

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✨ New Features

QRCodeImageBuilder - New Builder Pattern

Introduced a new API that provides static QR code image generation with a fluent builder pattern:

using var image = QRCodeImageBuilder.Create()
    .WithContent("Hello, World!")
    .WithECCLevel(ECCLevel.H)
    .WithSize(pixelsPerModule: 10)
    .WithColors(SKColors.Black, SKColors.White)
    .WithIcon(iconData, iconSizePercent: 15)
    .Build();

Related PR: #264

Enhanced Rendering Features

• Gradient color support (#263)
• Enhanced QR code rendering customization options (#261)
• Consolidated rendering methods and batch rendering (#259, #260)

Binary Data Support

• Added binary data encoding for QR codes (#204)
• Changed Binary CreateQrCode to receive ReadOnlySpan<char> (#205)

New APIs

• Added pre-calculate QR size API (#251)
• Provided GetRawData(IBufferWriter<byte> writer) API (#257)

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🐛 Bug Fixes

• Fixed invalid QR code generation when upgraded version (EciMode.Default UTF8 fallback) (#179)
• Fixed ECC encoding to ensure the remainder always produces the expected number of ECC words (#183)
• Fixed Penalty3 calculation to execute for rows and columns separately (#242)
• Fixed GetVersion not considering UTF8 BOM header bytes (#250)

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🔧 Refactoring & Internal Improvements

Encoding Redesign

• Replaced QR code generation with QREncoder and ECCEncoder (#176)
• Pipelined CreateQrCode (#197)
• QRCodeGenerator.CreateQrCode text API now forwards to binary API (#258)

Module Placement Improvements

• Internalized ModulePlacer (#190)
• Changed ModulePlacer receiver from ref QRCodeData to Span<byte> (#235)
• Used span instead of static field header signature (#201)

Code Quality

• Enabled ImplicitUsings (#181)
• Enabled Nullable (#182)
• Refactored and optimized QR code constants (#167)

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🛠️ Development Environment

• .NET 9.0 support (#170)
• Added .NET 8.0, handling .NET 5 or greater (#227)
• NativeAOT support (#267)
• Added benchmarks (#163, #226)
• Added README to NuGet (#162)
• Updated README (#270)

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🔗 Links

Full Changelog: 0.8.0...0.9.0