> For the complete documentation index, see [llms.txt](https://maps4fs.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://maps4fs.gitbook.io/docs/map-components/dem.md).

# DEM (Elevation)

## Overview: The Foundation of Terrain

The Digital Elevation Model (DEM) serves as the **fundamental terrain foundation** for your Farming Simulator map. Every hill, valley, slope, and elevation change is precisely defined by this critical component.

**Core Concept**: A DEM is essentially a 2D grid where each cell contains a height value, creating a digital representation of real-world topography that the game engine transforms into 3D terrain.

## Technical Specifications

### File Requirements

| Game Version | Image Dimensions                  | File Path                    | Data Format |
| ------------ | --------------------------------- | ---------------------------- | ----------- |
| **FS25**     | (map\_size + 1) × (map\_size + 1) | `map_directory/data/dem.png` | 16-bit PNG  |

**Data Structure:**

* **Channels**: Single channel (grayscale)
* **Data Type**: `uint16` (unsigned 16-bit integer)
* **Value Range**: 0 to 65,535 (2^16 possible elevation levels)
* **Color Depth**: 16-bit for maximum terrain detail precision

### Dimension Examples

**FS25 Standard Sizes:**

* 2048m map → 2049×2049 DEM
* 4096m map → 4097×4097 DEM
* 8192m map → 8193×8193 DEM
* 2048m map → 1025×1025 DEM
* 4096m map → 2049×2049 DEM

## Height Scale System

### Understanding Height Conversion

**The Challenge**: DEM pixels store values 0-65,535, but real-world elevations can exceed 8,000 meters. How does this work?

**The Solution**: The `heightScale` parameter acts as a **conversion multiplier** that transforms pixel values into real-world heights.

### Height Scale Configuration

**Default Value**: 255 (in Giants Editor maps) **Maximum Terrain Height**: `65,535 × (heightScale ÷ 65,535) = heightScale meters` **With Default Settings**: Maximum possible elevation = 255 meters

**Example Calculations:**

```
heightScale = 255  → Max height: 255m
heightScale = 512  → Max height: 512m
heightScale = 1000 → Max height: 1000m
```

### Practical Height Scale Selection

**For Flat Terrain (plains, farmland)**: 128-255m **For Moderate Hills**: 256-512m **For Mountain Regions**: 513-1000m+ **For Extreme Terrain**: 1000m+ (with performance considerations)

### Giants Editor Configuration

1. **Open Map**: Load your map in Giants Editor
2. **Select Terrain**: Choose terrain object in Scenegraph
3. **Terrain Tab**: Navigate to Attributes → Terrain
4. **Set heightScale**: Enter your calculated value
5. **Apply Changes**: Save and reload map (File → Reload)

## Units Per Pixel System

### Spatial Resolution Control

The `unitsPerPixel` parameter defines the **terrain resolution** by specifying how many meters each DEM pixel represents.

**Game Version Defaults:**

* **Available**: `unitsPerPixel = 1` (1 meter per pixel - highest detail)

### Resolution Impact

**Higher Resolution (unitsPerPixel = 1)**:

* ✅ Maximum terrain detail and precision
* ✅ Sharp elevation transitions and fine features
* ⚠️ Larger file sizes and longer processing times

**Lower Resolution (unitsPerPixel = 2+)**:

* ✅ Faster processing and smaller files
* ✅ Suitable for large, gradually changing terrain
* ⚠️ Less detailed elevation features

### Custom Resolution Configuration

1. **Access Settings**: Giants Editor → Terrain → Attributes
2. **Modify unitsPerPixel**: Set integer value (1, 2, 4, etc.)
3. **Recalculate DEM Size**: Adjust DEM image dimensions accordingly
4. **Test Results**: Reload and verify terrain quality

## Advanced Optimization Strategies

### Terrain Quality vs Performance

**Maximum Quality Setup**:

* `unitsPerPixel = 1`
* `heightScale = terrain-appropriate value`
* Full-resolution DEM with detailed elevation data

**Balanced Performance Setup**:

* `unitsPerPixel = 2`
* `heightScale = 512`
* Moderate resolution suitable for most use cases

**Large Map Optimization**:

* `unitsPerPixel = 4`
* Focus on broad terrain features rather than fine detail
* Ideal for 16×16km maps with performance constraints

### Professional Workflow

1. **Analyze Source Terrain**: Study your real-world elevation data
2. **Calculate Height Range**: Determine minimum to maximum elevation difference
3. **Set Height Scale**: Choose value that accommodates your terrain range with headroom
4. **Configure Resolution**: Balance detail needs with performance requirements
5. **Generate & Test**: Create DEM and verify terrain quality in Giants Editor
6. **Iterative Refinement**: Adjust parameters based on visual and performance results

**Pro Tip**: Always maintain some headroom in your height scale to accommodate manual terrain sculpting in Giants Editor without reaching the maximum elevation limit.