Creating Drawings¶

A drawing captures the 2D line geometry of a section cut at a point in time. This guide walks you through creating a drawing and understanding its options.

Prerequisites¶

At least one section must exist in the scene.
You must be in Object Mode.

Step 1: Select the Source Section¶

In the Sections list, click on the section you want to generate a drawing from to make it the active section.

Step 2: Open the Create Drawing Dialog¶

In the Drawings panel, click the + button. A dialog opens with the following settings:

General Settings¶

Setting	Description
Name	Name for the new drawing object.
Create At	Where the drawing object is placed after creation (see below).
Include Hidden Objects	When enabled, objects that are hidden in the viewport are also included in the drawing.

Create At options:

Section Origin – The drawing is placed at the section’s position and orientation in 3D space. Most common for keeping the drawing aligned with the model.
World Origin – The drawing is placed at (0, 0, 0). Useful when composing multiple drawings on a flat layout plane.
Custom – After creation you can place the object freely in the viewport.

Projection Settings¶

Toggle Enable Projection to also include the projected edges of the scoped geometry (not just the section outline).

When projection is enabled:

Setting	Description
Perspective	Applies perspective distortion to projected edges.
Distortion	Strength of the perspective distortion (only active when Perspective is on).
Limit	Only include geometry within a maximum distance from the section plane.
Distance	The maximum distance in scene units (only active when Limit is on).
Merge	Merge nearby projection vertices before BVH construction. Reduces geometry complexity and can improve hidden edge detection quality.
Dissolve	Dissolve near-collinear projection edges before BVH construction. Reduces silhouette edge count on smooth or subdivided geometry.
Hidden Edge Detection	Detect and store edges that are hidden behind other geometry. Stored in a separate edge layer.
Quality	Preset for hidden edge detection accuracy (Low, Medium, High, Ultra, Custom).

Step 3: Confirm and Inspect¶

Click OK to generate the drawing. Depending on the complexity of the scene and the selected options, this may take a few seconds. For complex scenes with HED enabled, it can take some minutes to complete, don’t close Blender or interrupt the process.

The drawing object is created inside the SP Drawings collection and becomes the active drawing in the Drawings list. It is a mesh object containing only edges.

Refreshing a Drawing¶

After changing the scene geometry or moving the section, the drawing is not updated automatically. To regenerate it:

Select the drawing in the Drawings list.
Click the Refresh Drawing button in the drawing’s actions row.

The drawing is regenerated in-place using all previously stored settings. Its current position in 3D space is preserved.

Working with Edge Layers¶

A drawing can contain up to three edge layers:

Section edges – the cross-section outline (always present).
Projection edges – visible projected geometry (present when projection was enabled).
Hidden edges – occluded edges detected by HED (present when HED was enabled).

To select a specific layer in the viewport, use the Select Edges buttons in the Actions sub-panel. This enters Edit Mode with the matching edges selected, so you can inspect, modify, or export them independently.