GDSII Preview for VS Code

A high-performance GDSII/OASIS file viewer for Visual Studio Code, featuring GPU-accelerated rendering for handling large integrated circuit layouts.

Features

• High-Performance Rendering: View large GDSII layouts smoothly directly within VS Code.
• Multi-Engine Support: Choose between WebGL (GPU), Canvas (CPU), or SVG rendering.
• Text Rendering: Displays text labels and annotations within the GDSII layout.
• Layer Management: Toggle layer visibility and customize layer colors.
• Cell Navigation: Inspect different cells within the GDS library.
• Interactive Controls:
  • Floating Toolbar: Draggable toolbar for common view operations.
  • Transformations: Flip (Horizontal/Vertical) and Rotate (CW/CCW) the layout.
  • Pan & Zoom: Smooth navigation with mouse and scroll wheel.
  • Fit View: Quickly center and fit the layout to the screen.
• Configuration Panel: Quick access to rendering settings and parameters directly within the viewer.
• Performance Optimizations:
  • Parallel Loading: Uses Web Workers to parse and process geometry off the main thread.
  • Viewport Culling: Only renders what is visible on screen.
  • Dynamic Level of Detail (LOD): Automatically reduces detail during fast interactions to maintain high frame rates.

Rendering Engines

This extension provides three rendering pipelines to suit different needs:

1. WebGL (Default & Recommended)

• Technology: GPU-accelerated rendering using WebGL.
• Pros: Extremely smooth Pan/Zoom performance ("Silky Smooth"). Handles millions of polygons with ease.
• Cons: Slightly longer initial load time due to polygon triangulation.
• Best For: Large, complex layouts (10MB+).

2. SVG

• Technology: Scalable Vector Graphics (DOM-based).
• Pros: Perfect vector fidelity at any zoom level. Easy to inspect via DOM tools.
• Cons: Very high memory usage and slow rendering for large files.
• Best For: Medium-sized layouts, high-quality static screenshots or where WebGL might be overkill or incompatible.

3. Canvas

• Technology: HTML5 Canvas 2D Context (CPU-based).
• Pros: Fast initial load. Good compatibility.
• Cons: Performance drops significantly with high polygon counts.
• Best For: Small cells, debugging.

Extension Settings

This extension contributes the following settings:

• gdsPreview.renderingEngine: Select the rendering backend.

  • webgl (Default): GPU acceleration.
  • canvas: Standard HTML5 Canvas.
  • svg: Legacy vector rendering.

• gdsPreview.fastModeThreshold: (Default: 10)

  • Controls the aggressiveness of the Dynamic LOD optimization (Only use for Canvas engine).
  • Specifies the minimum pixel size for polygons to be rendered during interaction (panning/zooming).
  • Higher values (e.g., 20, 50) improve interaction fluidity but temporarily reduce detail.

• gdsPreview.labelFontSize: (Default: 12)

  • Font size for text labels in pixels.

• gdsPreview.maxWorkers: (Default: -1)

  • Number of Web Workers to use for parallel processing.
  • Set to -1 to automatically use all available CPU cores.

• gdsPreview.chunkSize: (Default: 2000)

  • Number of polygons per data chunk streamed from Python.
  • Adjusting this can help balance memory usage and throughput.

• gdsPreview.pythonPath: (Default: python)

  • Path to the Python executable used for parsing GDSII files.
  • Useful if you have multiple Python installations or use a virtual environment.

Requirements

• Python 3: Required for parsing GDSII files.
• gdstk: Python library for GDSII manipulation.
  • The extension will attempt to automatically install gdstk if it is missing (pip install gdstk).
  • You can also install it manually using pip install gdstk.

Known Issues

• WebGL mode requires a graphics-capable environment.
• Very large files may take a moment to parse before the first render appears.