Quantum Geographic Information System (QGIS) is a powerful open-source platform that allows users to create, modify, and visualize geographic data. One of the standout features of QGIS is its ability to create 3D map views. This feature brings geographic data to life, allowing users to explore terrain, buildings, and other geographic features in three dimensions. Whether you’re a city planner, a geologist, or just a map enthusiast, QGIS’s 3D Map Views can provide a new perspective on the world around us. In this article, we will explore the process of creating a 3D view in QGIS and delve into some of its most fascinating features.
Creating a 3D Map View
- Navigate to View > 3D Map Views.
- Click “New 3D Map View” to open a floating panel.
- This panel replicates the extent and view of your main 2D map canvas but provides 3D navigation tools.
Manage 3D Map Views:
- Access the manager via View > 3D Map Views > Manage 3D Map Views.
- Here you can open, duplicate, remove, and rename your 3D map views.
- They are saved with your project, even when turned off.
Interacting with the 3D Map View
The 3D map view panel provides various functionalities:
- Camera Control: Move the view while maintaining the camera angle and direction.
- Zoom Full: Resize the view to encompass the entire layer extent or a set reference extent.
- Identify: Click on the terrain or a 3D feature to fetch information.
- Measurement Line: Measure horizontal distances between points.
- Animations: Show/hide the animation player for creating fly-through videos.
- Save as Image…: Export the current view as an image file.
- Export 3D Scene: Export the view as a 3D scene (.obj file) for further processing in applications like Blender. This includes terrain, vector features, and customizable settings.
- Set View Theme: Select predefined map themes to control which layers are displayed.
Options Menu:
- Access visual effects like shadows, lighting, and ambient occlusion.
- Synchronize views between 2D and 3D (camera position following either view).
- Show the visible camera area in the 2D map view.
- Configure 3D map view settings.
- Dock/undock the 3D Map View panel.
Configuring the 3D Scene
Expand the Options menu and click “Configure” to open the 3D configuration window. Here you can fine-tune various aspects of your 3D scene:
- General:
- Limit the 3D scene to a specific 2D map extent.
- Display the current extent as a rubberband in the main map canvas.
- Terrain:
- Choose the terrain type (flat, loaded DEM, online service, or loaded mesh dataset).
- Set the elevation source (raster layer or mesh layer).
- Adjust vertical scale to exaggerate elevation for dramatic effect.
- Control tile resolution for terrain detail (higher resolution increases complexity).
- Modify terrain shading using lighting or texture-based options.
- Lights:
- Add point lights or directional lights to illuminate your scene.
- Configure light properties like color, intensity, and attenuation.
- Shadows:
- Enable shadows with options for distance, bias, and resolution.
- Camera & Skybox:
- Override default camera settings.
- Show a 3D axis for reference and camera view adjustment.
- Enable camera view synchronization with the 2D map view.
- Include a skybox for a more immersive experience (panoramic or distinct faces).
- Advanced:
- Fine-tune terrain tile resolution, rendering complexity, and display options.
- Enable visual effects like Eye Dome Lighting and Screen-Space Ambient Occlusion for enhanced depth perception.
- Utilize debugging tools for troubleshooting terrain issues.
Explore your 3D map view using various navigation techniques:
- Tilt the terrain (up/down or drag with middle mouse button).
- Rotate the terrain (left/right or drag with middle mouse button).
- Change camera position (drag with left mouse button or arrow keys).
- Adjust camera altitude (Page Up/Down keys).
- Change camera orientation (Ctrl + arrow keys or drag with Ctrl + left mouse button).
- Zoom in/out (mouse wheel, zoom tools, or drag with right mouse button).
- Reset camera view (Zoom Full button).
Creating Animations
Bring your scene to life by creating fly-through animations:
- Activate the Animations tool.
- Click “Add keyframe” and set a time.
- Use navigation tools to position the camera for that keyframe.
- Repeat for additional keyframes at different times and positions.
- Preview the animation or export it as a series of images.
Advanced Rendering with 3D Vector Layers
Vector layers containing elevation data can be displayed in 3D. In the vector layer properties, under the 3D View section, check the “Enable 3D Renderer” box. This unlocks various options for customizing the 3D rendering of your vector layer.
Practical Applications of QGIS 3D Map Views
- Terrain Visualization: QGIS 3D Map Views can be used to visualize terrain based on a digital elevation model (DEM). This allows users to explore the topography of a region in three dimensions. For instance, a geologist studying a mountain range could use this feature to better understand the topography and make more accurate predictions about geological phenomena.
- Urban Planning: Urban planners can use 3D Map Views to create a 3D map view of buildings in a city. This can be particularly useful for planning and development. For example, a city planner could use this feature to visualize how a proposed building would fit into the existing cityscape.
- Environmental Studies: Environmental scientists can use 3D Map Views to visualize environmental data such as vegetation, water bodies, and other natural features. This can help in understanding the spatial distribution of these features and their impact on the environment. For instance, a conservation biologist could use this feature to study the distribution of a particular species across a landscape.
- Geological Studies: Geologists can use 3D Map Views to visualize geological features such as faults, rock formations, and mineral deposits. This can help in understanding the geological history of a region and predicting future geological events. For example, a geologist studying an active fault line could use this feature to better understand the fault’s structure and make more accurate predictions about potential earthquakes.
- Transportation Planning: Transportation planners can use 3D Map Views to visualize transportation networks such as roads, railways, and airports. This can help in planning and optimizing transportation routes. For instance, a transportation planner could use this feature to visualize a proposed new road and assess its impact on the existing transportation network.
- Disaster Management: In disaster management, 3D Map Views can be used to visualize areas prone to natural disasters such as floods, landslides, and earthquakes. This can help in planning and implementing disaster management strategies. For example, a disaster management team could use this feature to visualize a flood-prone area and plan evacuation routes.
Conclusion
QGIS 3D map views empower you to create compelling 3D visualizations of your geospatial data. From configuring the terrain and lighting to crafting fly-through animations, you can transform your maps into interactive and informative experiences. With a little exploration and experimentation, you can unlock the full potential of QGIS’s 3D capabilities and bring your geographic stories to life in a whole new dimension.
