ACadSharp.Image

High-performance DXF/DWG to image renderer for .NET, built on ACadSharp and ImageSharp.

Transform CAD drawings into raster images for previews, CI/CD pipelines, web applications, documentation, and automated workflows — with zero AutoCAD dependency.

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✨ Features

• 🎨 Multi-format export — PNG, BMP, JPEG, GIF, and WebP support
• 📐 Full CAD support — Render DXF and DWG files with ACadSharp
• 🖼️ Customizable output — Control width, height, padding, background color, and quality
• 📊 Space support — Model space, paper layouts, and viewports
• 🎭 Layer filtering — Hide specific layers with --hide-layer option
• ⚡ CLI tool — Cross-platform command-line interface for automation
• 🔧 Library API — Full .NET integration with intuitive fluent-style configuration
• 🚀 Native AOT - Publish as standalone native binaries with zero .NET runtime requirement
• 📚 Fully documented — Complete XML IntelliSense support

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📦 Installation

NuGet Package

dotnet add package ACadSharp.Image

CLI as Global Tool

dotnet tool install --global ACadSharp.Image.Cli

Update to latest version:

dotnet tool update --global ACadSharp.Image.Cli

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🚀 Quick Start

Library Usage

Render a DWG file with custom settings:

using ACadSharp.IO;
using ACadSharp.Image;
using SixLabors.ImageSharp;

// Load CAD document
var document = DwgReader.Read("part.dwg");

// Configure and export
var exporter = new ImageExporter("output.webp");
exporter.Configuration.Width = 2000;
exporter.Configuration.Height = 1400;
exporter.Configuration.SetPadding(24, 12);
exporter.Configuration.BackgroundColor = Color.Parse("#ffffff");
exporter.Configuration.OutputQuality = 90;

// Optional: hide specific layers
exporter.Configuration.HideLayer("DIMENSIONS");
exporter.Configuration.HideLayer("ANNOTATIONS");

exporter.AddModelSpace(document);
exporter.Save("./output-directory/filename.webp", ImageExportFormat.Webp);

Multi-page export:

var exporter = new ImageExporter();
exporter.AddPaperLayouts(document);
exporter.Save("./output-directory/filename.png", ImageExportFormat.Png);

CLI Usage

Basic rendering:

cad-to-image "drawing.dxf" --format webp --width 1400 --height 1400 --quality 85

Custom background & dimensions:

cad-to-image "part.dwg" --format png --width 1800 --height 1200 --background "#0c0c0c"

Add padding around the drawing:

cad-to-image "part.dwg" --format png --padding 24
cad-to-image "part.dwg" --format png --padding 24,12
cad-to-image "part.dwg" --format png --padding 24,12,40,20

Hide multiple layers:

cad-to-image "complex.dxf" --hide-layer "DIMENSIONS" --hide-layer "ANNOTATIONS" --hide-layer "BORDER"

Export paper layouts:

cad-to-image "multi-sheet.dwg" --paper-layouts --output ./sheets/

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📖 CLI Reference

Usage:
  cad-to-image <input.dxf|input.dwg> [options]

Options:
  -o, --output <path>         Output file or directory path.
  -f, --format <format>       png, bmp, jpg, jpeg, gif, webp.
  -w, --width <pixels>        Output width in pixels. Default: 1600.
  -H, --height <pixels>       Output height in pixels. Default: 900.
  -p, --padding <value>       Padding in pixels: <all>, <x,y>, or <left,top,right,bottom>.
  -b, --background <color>    Background color name or hex value. Default: white.
  -q, --quality <1-100>       Output quality for lossy formats. Default: 90.
      --paper-layouts         Export paper layouts instead of model space.
      --hide-layer <name>     Hide entities on the specified layer. Can be used multiple times.
      --help, -h, -?          Show this help text.

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🏗️ Architecture

ACadSharp.Image/
├── ImageExporter.cs          # Main public API
├── ImageConfiguration.cs     # Fluent configuration
├── ImagePage.cs              # Page representation
├── RenderedImagePage.cs      # Rendered output
└── Rendering/
    ├── ImagePageRenderer.cs      # Page-level rendering
    ├── EntityRenderDispatcher.cs # Entity routing & primitive drawing
    ├── SplineRenderer.cs         # Spline path generation and sampling
    ├── TextRenderer.cs           # Text and MText rendering
    ├── ImageRenderContext.cs     # Coordinate transforms
    └── ImageStyleResolver.cs     # Color & line weight resolution

The library follows a clean architecture pattern:

• ImageExporter - Public API for adding CAD content
• ImagePage - Represents individual renderable pages
• Rendering pipeline - Transforms CAD entities to pixel coordinates and draws them
• Configuration - Fluent, extensible settings for customization

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💡 Advanced Usage

Layer Filtering

Control visibility of specific layers programmatically:

var exporter = new ImageExporter();

// Hide multiple layers (case-insensitive)
exporter.Configuration.HideLayer("0");
exporter.Configuration.HideLayer("DEFPOINTS");
exporter.Configuration.HideLayer("ANNO_TEXT");

exporter.AddModelSpace(document);

Custom Line Weights

Override default line weight values:

exporter.Configuration.SetLineWeight(LineWeightType.W25, 0.30);
exporter.Configuration.LineWeightScale = 1.5f; // Scale all weights

Text & Font Configuration

Customize text rendering:

exporter.Configuration.FontFamilyName = "Consolas";
exporter.Configuration.ArcPrecision = 512; // Higher = smoother arcs

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🛠️ Development

Prerequisites

• .NET 6.0 SDK or later
• Any IDE with C# support (VS 2022, VS Code, Rider)

Build & Test

# Clone and build
git clone https://github.com/slaveoftime/ACadSharp.Image.git
cd ACadSharp.Image
dotnet restore
dotnet build
dotnet format --verify-no-changes

# Run tests
dotnet test

Measure Render Performance

Use the repeatable sample-render benchmark script:

powershell -ExecutionPolicy Bypass -File .\artifacts\measure-render.ps1
powershell -ExecutionPolicy Bypass -File .\artifacts\measure-render.ps1 -Iterations 10

Run Examples

dotnet run --project ./ACadSharp.Image.Cli/ACadSharp.Image.Cli.csproj -- "./Samples/6-57-1119.dxf" --width 300 --height 200 --hide-layer OPTIONAL_DIMENSIONS

dotnet run --project ./ACadSharp.Image.Cli/ACadSharp.Image.Cli.csproj -- "./Samples/HSK80AHCP16190M_BMG.dwg" --format webp --width 1200 --height 760

dotnet run --project ./ACadSharp.Image.Cli/ACadSharp.Image.Cli.csproj -- "./Samples/Subaru Logo Vector Free Wrap.dxf" --format webp --width 1200 --height 700 --background "#a0a7ae"

Build NuGet Package

dotnet pack ./ACadSharp.Image/ACadSharp.Image.csproj -c Release
dotnet pack ./ACadSharp.Image.Cli/ACadSharp.Image.Cli.csproj -c Release
dotnet tool install -g --add-source ./ACadSharp.Image.Cli/bin/Release ACadSharp.Image.Cli

Publish Native Binary (AOT)

Zero-dependency standalone executables:

# Windows x64
dotnet publish ./ACadSharp.Image.Cli/ -c Release -r win-x64 --self-contained -p:PublishAot=true

# Linux x64
dotnet publish ./ACadSharp.Image.Cli/ -c Release -r linux-x64 --self-contained -p:PublishAot=true

# macOS ARM64
dotnet publish ./ACadSharp.Image.Cli/ -c Release -r osx-arm64 --self-contained -p:PublishAot=true

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🔄 Migration Notes

Recent modernization work includes intentional API tightening:

• ImageExporter.Pages is now a read-only collection view.
• ImagePage.Entities and ImagePage.Viewports are now read-only collection views.
• Add content through ImageExporter.Add(...), ImagePage.Add(...), ImagePage.AddEntity(...), and ImagePage.AddViewport(...).
• ImageConfiguration.HiddenLayers is now read-only; use HideLayer, HideLayers, ShowLayer, and ClearHiddenLayers.
• ImageConfiguration.LineWeightValues is now read-only; use SetLineWeight, RemoveLineWeight, and ClearLineWeights.

These changes preserve the rendering behavior while making mutation points explicit and easier to maintain.

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🤝 Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

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📄 License

This project is released under the MIT License.

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🌟 Support

If you find this project helpful, please consider giving it a ⭐️ on GitHub! It helps others discover the project.

Questions or issues? Open an issue or start a Discussion.