Roof Drawing
The page explains how to create accurate roof geometry by drawing a 2D roof outlines and inner edges, defining slopes to generate a 3D model, managing map providers, and adding obstacles.
Purpose of This Page
The Roof Drawing page is the foundation of the entire design and feasibility workflow in solarVis.
Users start by drawing a 2D roof outline, optionally dividing it using inner edges, and then assigning slopes to convert the drawing into a 3D roof model.
This 3D model is later used for:
Panel placement
Shading analysis
Energy and feasibility calculations
What You Can Do Here
On this page, you can:
Switch between View Mode and Draw Mode
Draw and edit the roof outline in 2D
Use snapping and angle guides for precision
Use Inner Edge Detector to create interior divisions
Add and manage roof obstacles
Edit building height and roof faces
Assign slopes to convert 2D geometry into 3D roof faces
Adjust building height and roof face properties
Change map provider or upload custom imagery
Navigate and rotate the 3D scene
On this page, changes are saved automatically after you make them.
Modes
Explains the available interaction modes used to view, draw, and modify roof geometry.
View Mode
View Mode is used to inspect the roof model without modifying its geometry.
In View Mode, you can:
Rotate, pan, and zoom the scene
Access and review the building height
Select roof faces to inspect technical properties like slope, azimuth, and area information
Select the building for editing or moving the roof and flattening the faces
Switch back to Draw Mode when geometry changes are needed
This mode is recommended for quality checks and validation.
Draw Mode
Draw Mode is used to create and edit the 2D roof outline.
Drawing the Outline
Click to place vertices
Continue clicking to define edges
Close the polygon to complete the outline
Orange guides show perpendicular and parallel alignment
Vertices snap automatically to create a clean roof outline
Edge lengths are displayed automatically
Undo and redo buttons are always available
The outline is still 2D at this stage. A slope assignment is required to convert it into 3D.
When subdividing or splitting the roof, use the Escape (Esc) key to complete the current line drawing.
Converting From 2D to 3D
Once the roof outline is complete, slopes are assigned to the roof faces.
Slope Assignment
Select a face or edge
Adjust the slope value from the right panel
Or drag the slope arrow directly on the model
Each slope transforms that face into a 3D plane
Building height can also be adjusted numerically or visually.
Each slope transforms a flat face into a 3D plane with a defined orientation. Also, different faces can have different slopes.
Inner Edge Detector
The Inner Edge Detector helps users quickly divide complex roof shapes into smaller faces.
How It Works
Analyzes the angles of the roof outline
Generates an inner line along the bisector
Suggests these lines as possible interior divisions
What Users Can Do
Accept suggested inner edges
Adjust or reposition them
Remove unnecessary edges
Add the missing inner edges manually
Inner edges define geometry only; they do not assign slopes automatically.
Obstacles
Obstacles represent physical objects on the roof where solar panels cannot be placed.
Obstacles affect shading calculations.
Adding Obstacles
You can add obstacles as:
Rectangles
Circles
Polygons
Each obstacle can be resized, moved, and positioned precisely.
You can also duplicate obstacles to quickly model repetitive rooftop elements, or their height above the roof surface can be adjusted manually.
Obstacle Features
Draw rectangular obstacles
Resize by dragging corners
Move obstacles freely on the roof
Set obstacle height for shading calculations
Obstacles can be aligned directly with the roof surface using the Flush option.
Common Obstacle Examples
Chimneys
Skylights
Satellite dishes
Roof Dormers
Roof dormers are structural roof elements that extend vertically from the main roof surface and create additional roof faces.
In solarVis, dormers are modeled as part of the roof geometry, not as simple obstacles. This allows dormer faces to participate in slope and panel placement logic.
Dormers are commonly used in residential and hotel-type buildings and must be defined accurately to avoid incorrect panel layouts and shading results.
Adding a Dormer
Dormers can be added while working in Draw mode.
To add a dormer:
Switch to Draw mode
Select the Roof Dormer tool from the top toolbar
Choose a dormer type
Click on the target roof face to place the dormer
Once placed, the dormer becomes part of the roof structure.
Dormer Types
SolarVis supports multiple dormer geometries to reflect real-world roof structures.
Available dormer types include:
Shed Dormer
A single-slope dormer with one roof plane.
Gable Dormer
A dormer with two sloped faces forming a ridge.
Hip Dormer
A dormer with multiple sloped faces converging at the top.
Each dormer type generates its own roof faces automatically.
Dormer Roof Faces Properties
When a dormer is selected, its properties are shown in the right-side panel.
You can adjust the following parameters:
Width
Defines the horizontal size of the dormer.
Length
Defines how far the dormer extends along the roof surface.
Pitch
Defines the slope angle of the dormer roof faces.
All values are entered numerically and update the model in real time. Dormer roof faces are treated the same as main roof faces in panel placement and shading calculations.
Editing Dormer
Dormers can be edited after placement.
You can:
Resize the dormer by changing the width and length
Adjust pitch to match architectural drawings
Move the dormer across the roof face
Reposition it to avoid conflicts with panels or obstacles
Edits are applied instantly to all dormer roof faces.
Duplicating a Dormer
Dormers can be duplicated to quickly recreate repeating roof structures.
How Duplication Works
Select an existing dormer
Click the Duplicate action from the toolbar or context menu
A copy of the dormer is created with the same:
Dormer type
Dimensions
Pitch values
The duplicated dormer can then be moved and adjusted independently.
Dormers vs Obstacles
Dormers are not obstacles.
Key differences:
Dormers create new roof geometry
Obstacles only block panel placement
Use dormers when the structure is part of the roof.
Use obstacles for rooftop objects, such as chimneys or vents, on the roof surface.
Undo & Redo & Delete Buttons
Undo
Reverts the last drawing or edit made on the roof layout.
Redo
Restores the last drawing or edit that was undone.
Delete
Removes everything that you made, like obstacles, or drawing from the roof.
Keyboard Shortcuts
Keyboard shortcuts allow you to work faster and more precisely while drawing and editing roofs in solarVis.
View States
1: Top View
2: Front View
3: Side View
4: Perspective View
5: Isometric View
N: Reset North
View shortcuts change the camera view without modifying geometry.
Design Tools
E: Edit Mode
C: Draw Mode
V: View Mode
M: Move Mode
I: Inner Edge Tool
These shortcuts switch between drawing and editing tools.
Visibility Controls
L: Show or Hide Dimensions
G: Show or Hide Satellite Ground
Visibility shortcuts reduce visual clutter during editing.
Actions
Ctrl + Z: Undo
Ctrl + Shift + Z: Redo
Delete or Backspace: Delete
Ctrl + C: Duplicate
Action shortcuts manage editing history and objects.
Quick Add Obstacles
Alt + C: Add Circle Obstacle
Alt + R: Add Rectangle Obstacle
Alt + P: Add Polygon Obstacle
Quick add shortcuts instantly create obstacles for shading and no-go zones.
Building Editing
It allows you to manage the overall structure of the roof model after the 2D outline has been converted into 3D.
Building-level edits affect all connected roof faces and are critical for accurate shading, production, and feasibility calculations.
The drawn roof can be duplicated easily instead of creating it again from scratch.
Accessing Building Editing
To access building editing tools:
Switch from Draw mode to View mode
Click on the building body
The Building panel opens on the right side
This panel contains actions that apply to the entire building or selected roof faces.
Building Panel Actions
From this panel, you can:
Edit roof geometry and slopes numerically
You can resize the building horizontally by dragging a horizontal edge outward or inward. This will extend the drawn edge and adjust the building size accordingly.
By dragging the edges upward, you can set the desired roof slope
Move the entire roof that you drew
Movement does not change geometry, slopes, or dimensions.
Flatten selected roof faces
Flattening is useful to reset incorrect slope assignments or inner edges.
Adjust building height numerically or visually in the scene
Building height affects shading calculations and multi-level roof behavior.
Roof Face Selection
Individual roof faces can be selected for detailed inspection or editing.
To select a roof face:
Double-click on the face
The Roof Face Information panel opens
This allows face-level control without affecting the entire building.
Roof Face Information
When a roof face is selected, the following data is displayed:
Slope represents the inclination of the roof face.
Azimuth represents the compass orientation of the roof face
Area represents the usable surface of the roof face.
This allows precise control over multi-level or complex roof structures.
🧷 Best Practices for Building Editing
Always validate the roof face slope and azimuth before panel placement
Use Flatten Faces to fix early mistakes instead of redrawing
Inspect each roof face individually on complex roofs
Accurate building editing ensures reliable results across all downstream modules.
Map Provider and Imagery Controls
Map and imagery selection is a critical first step for accurate roof drawing.
These controls are located at the bottom left of the screen.
Satellite Visibility
You can toggle satellite imagery on or off to:
Reduce visual clutter
Focus on geometry and measurements
Improve drawing precision
Dimension Visibility
You can show or hide dimensions to:
Validate edge lengths
Reduce screen noise during editing
Dimension labels remain readable while zooming in and out.
Map Provider Selection
You can choose between different map providers depending on availability and resolution:
Google Maps
Google Maps HD (Google Solar API)
Azure Maps
Switching providers can improve image clarity, edge visibility, or alignment accuracy for specific locations.
Availability of solar and roof data for Google Maps HD depends on Google Maps Solar API coverage. Please check the coverage map on the website below to confirm whether data is available for your location.
Sometimes, the browser’s default settings may not support “WebGL”. Please check whether your browser supports WebGL by using the link.
If you see the “WebGL is not supported” error, the game engine used for roof drawing may not work properly. To avoid this issue, please make sure that WebGL is enabled in your browser settings.
You can follow the steps in the link to update your settings.
Custom Images
In addition to map providers, you can upload custom images.
Common use cases include:
Architectural roof plans
Drone imagery
High-resolution site photos
Uploaded images can be aligned to the coordinate system and used as a drawing reference.
This is especially useful when satellite imagery is outdated or unclear.
Camera and Navigation
Camera tools located bottom right affect only how the model is viewed.
They do not change geometry.
Navigation Compass
The compass allows you to:
Jump to preset views, such as top or side
Validate roof orientation
Rotate the view around the building
It can be rotated to view around the building by right-clicking and dragging the mouse
Camera Tools
You can:
Pan the view
Zoom in
Zoom out
These tools help inspect details without modifying the model.
The map can be panned by pressing and dragging the mouse wheel.
Related Pages
If you encounter any issues, feel free to contact us.
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