Utility_Apps/Blender/simple scripts/CSV Terrain Import for Blender

CSV Terrain Import for Blender

This workflow imports survey-style CSV point data into Blender as:

1. Empties (named from the label column)

2. A triangulated 3D mesh surface generated from those empties

It handles:

• Large world coordinates (offsets near origin)

• Mirrored Y axis correction

• Z normalization (lowest point = 0)

• Unit conversion (CSV in feet → Blender scene units)

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Requirements

• Blender 4.x

• SciPy installed in Blender’s Python (for Delaunay triangulation)

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Installing SciPy in Blender

✅ Correct Way to Install SciPy for Blender 4.5

You must use Blender’s Python executable, not your system one.

Open PowerShell or CMD and run:

Code

"C:\\Program Files\\Blender Foundation\\Blender 4.5\\4.5\\python\\bin\\python.exe" -m ensurepip

Then:

Code

"C:\\Program Files\\Blender Foundation\\Blender 4.5\\4.5\\python\\bin\\python.exe" -m pip install --upgrade pip

Then:

Code

"C:\\Program Files\\Blender Foundation\\Blender 4.5\\4.5\\python\\bin\\python.exe" -m pip install scipy

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CSV Format

Your CSV must include the following headers:

Code

id,x,y,z,label

Example:

Code

1,436942.2079,856128.116,869.0791,3/4"RBR
2,436943.0254,856128.0656,868.833,BT

Assumptions:

• Coordinates are in feet

• X/Y are projected coordinates

• Z is elevation

• label will become the Empty name

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Step 1 — Import CSV as Empties

Open Blender:

1. Go to Scripting workspace

2. Create a new script

3. Paste the “Script 1” code

4. Set your csv_path

5. Run the script

What this does:

• Creates a collection named CSV_Points

• Creates one Empty per CSV row

• Offsets X/Y near origin

• Flips Y axis to match Blender

• Sets lowest Z to 0

• Converts feet → Blender units automatically

You should now see labeled empties in 3D space.

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Step 2 — Generate Triangulated Mesh

1. Create a new script

2. Paste the “Script 2” code

3. Run it

What this does:

• Reads all empties in CSV_Points

• Performs Delaunay triangulation (XY plane)

• Builds a 3D triangulated mesh using the empty Z values

• Creates a new object named TriangulatedMesh

You now have a terrain surface mesh.

Here’s a short section you can add to your README.md explaining the filtering behavior.

You can paste this anywhere after the “Generate Triangulated Mesh” step.

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Skipping Certain Survey Points

The triangulation script supports excluding specific points based on the name of the Empty (which comes from the CSV label column).

This is useful because survey datasets often contain points that should not be part of a terrain surface, for example:

• House corners

• Utilities

• Reference marks

• Temporary layout points

The script ignores any Empty whose name contains certain keywords.

Current defaults:

HSE FOO BAR

The filtering is case-insensitive.
Examples that will be skipped:

HSE  
hse\_corner  
foo\_marker  
BAR-TEST  
my\_house\_hse\_point

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How It Works

Before triangulation, the script checks each Empty in the CSV_Points collection and removes any that match an exclusion keyword. Only the remaining points are used to build the terrain mesh.

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Customizing the Filter

You can edit the list inside Script 2:

EXCLUDE_KEYWORDS = ["HSE", "FOO", "BAR"]

Why This Matters

Triangulation assumes every point belongs to the same continuous surface.
If non-terrain points are included (tops of foundations, utility lids, walls, etc.), the mesh will produce long spikes, inverted triangles, or unrealistic slopes.

Filtering produces a much cleaner and more accurate terrain model.

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Unit Handling

This workflow assumes:

• CSV coordinates are in feet

• Blender scene may be meters, feet, etc.

The script automatically converts:

Code

CSV feet → meters → Blender units

So your terrain will scale correctly regardless of Blender’s unit settings.

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Coordinate Adjustments Explained

Offset to Origin

Large survey coordinates can cause floating-point precision issues.

The script subtracts:

• Minimum X

• Minimum Y

• Minimum Z

So geometry is created close to (0,0,0).

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Y-Axis Flip

Many survey systems increase Y in the opposite direction from Blender.

The script flips Y so the terrain is not mirrored.

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Common Issues

Mesh looks mirrored

Ensure the Y-flip line exists:

Python

y_adj = -(y - y_offset) * scale

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Mesh scale is wrong

Verify:

• CSV is truly in feet

• Blender unit system is set correctly

• CSV_UNIT_TO_METERS = 0.3048

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SciPy Import Error

If you see:

Code

ModuleNotFoundError: No module named 'scipy'

Reinstall SciPy into Blender’s Python.

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Recommended Workflow

For large terrain datasets:

1. Import empties first

2. Inspect distribution visually

3. Then triangulate

4. Optionally delete empties after mesh creation

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Optional Improvements

Possible enhancements:

• Assign vertex colors based on label

• Assign materials per label

• Automatically delete empties after mesh creation

• Add smoothing or decimation

• Convert to Geometry Nodes workflow