---
title: "CadSettings"
canonical_url: "https://www.nutrient.io/api/python/settings/format/cad-settings/"
md_url: "https://www.nutrient.io/api/python/settings/format/cad-settings.md"
last_updated: "2026-06-12T15:43:20.748Z"
description: "Settings for Cad. Values fall back through three levels: document → SDK → built-in default."
---

Settings for Cad. Values fall back through three levels: document → SDK → built-in default. Writes target the document only when set on a document's settings, otherwise the SDK globally when set on SdkSettings.

**Tags:** `Format`

```python

from nutrient_sdk import CadSettings

```

## Construction

`CadSettings` is accessed through a [`Document`](/api/python/document/) instance for per-document overrides, or via [`SdkSettings`](/api/python/settings/document/sdk-settings/) for SDK-wide defaults.

```python

# Per-document override

with Document.open("input.pdf") as doc:
    settings = doc.settings.cad_settings
    settings.some_field = new_value          # mutate fields directly

# SDK-wide default (applies to all documents)

SdkSettings.cad_settings.some_field = new_value

```

Settings are configured by writing to fields on the returned object. The settings property itself cannot be reassigned — `doc.settings.cad_settings = other_settings` is rejected.

## Properties

### canvas_background_color

```python

@property
def canvas_background_color(self) -> Color

@canvas_background_color.setter
def canvas_background_color(self, value: Color) -> None

```

The canvas background color.

**Type:** [`Color`](/api/python/types/color/)

**Default:** `Color.White`

---

### enable_line_weight

```python

@property
def enable_line_weight(self) -> bool

@enable_line_weight.setter
def enable_line_weight(self, value: bool) -> None

```

This flags controls the support of line weight. It is the same command option as AutoCad "Lineweight".

**Type:** `bool`

**Default:** `true`

---

### rendering_layout_mode

```python

@property
def rendering_layout_mode(self) -> RenderingLayoutMode

@rendering_layout_mode.setter
def rendering_layout_mode(self, value: RenderingLayoutMode) -> None

```

The rendering layout mode that determines how the canvas size and rendering origin are computed.

**Type:** [`RenderingLayoutMode`](/api/python/enums/rendering-layout-mode/)

**Default:** `RenderingLayoutMode.ZoomExtents`

---

### render_zoom

```python

@property
def render_zoom(self) -> float

@render_zoom.setter
def render_zoom(self, value: float) -> None

```

The zoom level for rendering CAD documents.

**Type:** `float`

**Default:** `The default value is 0.`

---

### thumbnail_mode

```python

@property
def thumbnail_mode(self) -> bool

@thumbnail_mode.setter
def thumbnail_mode(self, value: bool) -> None

```

Indicates whether thumbnail mode is enabled for CAD rendering.

**Type:** `bool`

**Default:** `false`

---

### unit_mode

```python

@property
def unit_mode(self) -> UnitMode

@unit_mode.setter
def unit_mode(self, value: UnitMode) -> None

```

The unit mode for measurement in CAD documents.

**Type:** [`UnitMode`](/api/python/enums/unit-mode/)

**Default:** `UnitMode.UnitPoint`

---

---

## Related pages

- [Per-document override](/api/python/settings/format/email-settings.md)
- [Per-document override](/api/python/settings/format/html-settings.md)
- [Per-document override](/api/python/settings/format/image-settings.md)
- [Format](/api/python/settings/format.md)
- [Per-document override](/api/python/settings/format/pdf-settings.md)
- [Per-document override](/api/python/settings/format/jpeg-settings.md)
- [Per-document override](/api/python/settings/format/spreadsheet-settings.md)
- [Per-document override](/api/python/settings/format/markdown-settings.md)
- [Per-document override](/api/python/settings/format/word-settings.md)