TIN Surface Tools Overview 

The TIN Surface Tools in SPCAD provide all the functionality you need to build, edit, and manage digital terrain models directly in your CAD environment. Accessible through the Manage panel in the TIN Surface Manager, these tools support multiple input types and workflows—from survey points and contours to 3D faces and legacy data.

Each tool ensures efficient terrain data capture, processing, and modeling with full compatibility across SPCAD’s modern surface management system.

1. Create TIN From Points 

Use this tool to generate a TIN surface from Cogo Points or any point-based data. You can source data from:

• Cogo Point Groups (collections of survey points)
• Points on specific layers or blocks
• Interactive on-screen selections

Features

• Direct classification of points for visual styling
• Optional breaklines and clipping boundaries
• Optimized for topographic and survey data

Use Case Example

Create a surface from ground-level topographic points collected in the field and organized into a Point Group. 

2. Create TIN From Contours 

The Create TIN from Contours command converts 2D or 3D contour polylines into a TIN surface. It automatically extracts elevation data from polyline vertices to produce a realistic terrain model.

Features

• Recognizes elevation from Z values in polylines 
• Automatically fills gaps between contours with triangulated faces 
• Suitable for scanned topographic maps or imported GIS datasets 

Use Case Example

Generate a surface model for an area using contour data imported from a shapefile or DWG. 

3. Create TIN from 3D Faces 

This tool allows you to build a new TIN surface from existing 3DFace entities in the drawing. It is useful for reusing manually drawn terrain meshes or converting older 3D drawings into structured TIN surfaces. 

Features

• Converts raw 3DFace geometry into a formalized TIN model 
• Extracts elevation data directly from face vertices 
• Supports editing, reclassification, and export after conversion 

Use Case Example

Convert a conceptual terrain model created using AutoCAD 3DFaces into a full-featured TIN with analysis capabilities. 

4. Upgrade Legacy TIN Surface 

Legacy surfaces created in earlier versions of your application can be upgraded to the current TIN model format using this command. This unlocks access to modern tools such as: 

• Classification by elevation range 
• Advanced editing (swap edge, redefine) 
• Full compatibility with import/export workflows 

Features 

• Preserves original geometry 
• Enhances metadata with elevation statistics 
• Unlocks new visual styles and export formats 

Use Case Example

Bring a previously created TIN from older projects into your current environment for further refinement or export.