Draw directly on the model or on the screen with the Pen tool, allowing the flexiblity to annotate in the best way for you.

Access the Pen

To begin using the Pen, select Tools from the main menu, and select Pen from the Tools menu.

2D Pen

By default, the 2D Pen is selected. This tool allows you to draw on the screen in front of the model. 2D drawings stay in place when the tool is deselected, allowing you to navigate the model separately.

Toggle 2D and 3D

To swap between the 2D and 3D pens, use the toggle in the bottom left corner.

3D Pen

Choose 3D Pen to draw directly on the model in 3D. Start drawing on the model by dragging across a structure. To rotate or zoom into the model, tap ‘Done’ in the top right corner of the screen and navigate the model as normal.

Pen Options

Change the pen style using the options available by tapping the button at the centre of the bottom of the screen. The current style is previewed in the center of the button.

Brush Size

Change the size of the pen using the options to the right-hand side of the options button.


Select a color from the array to the left of the options button.


Drag the slider above the options button to change the transparency of the Pen.

Rotating the model

To rotate, zoom, or change the model position, tap Done in the top right corner and navigate the model as normal.

Undo and Redo

Undo and redo Pen strokes using the buttons at the top of the tool selection panel.

Clear Pen

When using the Pen tool, tap the ‘Clear Pen’ button in the top left corner of the screen to remove all 2D or 3D pen work. At any point, select the ‘Clear’ button in the top left corner of the screen, and select to Clear Pen or to Clear All.

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