This Quarto extension allows you to render D2 diagrams directly within your markdown documents.

Main features:

• Render D2 diagrams directly within your Quarto markdown documents.
• Control the appearance and layout of your diagrams using global settings or code block attributes.
• Tune the width and height of the resulting figures using the “width” and “height” arguments.

This extension was inspired by ram02z/d2-filter.

Ensure that you have D2 installed on your system.

Run the following command to add this extension to your current project:

quarto add data-intuitive/quarto-d2

This will install the extension under the _extensions subdirectory. If you’re using version control, you will want to check in this directory.

logs: {
  shape: page
  style.multiple: true
}
user: User {shape: person}
network: Network {
  tower: Cell Tower {
    satellites: {
      shape: stored_data
      style.multiple: true
    }

    satellites -> transmitter
    satellites -> transmitter
    satellites -> transmitter
    transmitter
  }
  processor: Data Processor {
    storage: Storage {
      shape: cylinder
      style.multiple: true
    }
  }
  portal: Online Portal {
    UI
  }

  tower.transmitter -> processor: phone logs
}
server: API Server

user -> network.tower: Make call
network.processor -> server
network.processor -> server
network.processor -> server

server -> logs
server -> logs
server -> logs: persist

server -> network.portal.UI: display
user -> network.portal.UI: access {
  style.stroke-dash: 3
}

To use the d2 filter, add the d2 filter to your quarto document. Next, add the .d2 class to any code blocks containing D2 diagram code. Here is a basic example:

---
title: "D2 Example"
filters:
  - d2
---

```{.d2}
x -> y
```

With this setup, the d2 filter will process any code blocks with the .d2 class, applying the attributes you specify.

That’s it! Now you know how to use the d2 filter to generate diagrams in your quarto documents.

You can specify additional attributes to control the appearance and layout of the diagram.

• theme: Specifies the theme of the diagram. Default is "NeutralDefault". Options are "NeutralDefault", "NeutralGrey", "FlagshipTerrastruc"t, "CoolClassics", "MixedBerryBlue", "GrapeSoda", "Aubergine", "ColorblindClear", "VanillaNitroCola", "ShirelyTemple", "EarthTones", "EvergladeGreen", "ButteredToast", "DarkMauve", "Terminal", "TerminalGrayscale", "Origami".
• layout: Specifies the layout algorithm to use. Default is "elk". Options are "dagre", "elk", "tala".
• format: Specifies the format of the output image. Default is svg. Option are "svg", "png", "pdf".
• sketch: Whether to use a “sketch” style for the diagram. Default is false.
• pad: Amount of padding around the diagram. Default is 100.
• caption: Caption to add to the diagram.
• folder: Folder where the generated diagram will be saved. If not provided, the image will be embedded inline in the document (HTML only).
• filename: Name of the output file.
• width: Width of the output image. Default is 100%. Examples are "100px", "50%", "3cm".
• height: Height of the output image. Default is auto. Examples are "100px", "50%", "3cm".
• echo: Whether to echo the original diagram code in the output. Default is false.
• embed_mode: How to embed the diagram in the output. Default is "inline" for HTML output and "link" for other output formats. Options are "inline", "link", "raw".

Here’s an example that uses multiple attributes:

```{.d2 theme="CoolClassics" layout="elk" pad=20 caption="This is a caption" width="50%"}
x -> y -> z
```

You can set global options for the d2 filter using the d2 field in the document metadata. Here’s an example:

---
title: "D2 Example"
filters:
  - d2
d2:
  layout: elk
  theme: "GrapeSoda"
---

```{.d2 width="40%" echo=true}
x -> y -> z
```

You can specify a folder where the generated diagram will be saved using the folder attribute. The filename attribute allows you to set a custom name for the output file.

```{.d2 folder="./images" filename="my_diagram"}
x -> y -> z
```

Interactive diagrams will only work when the Quarto output format is HTML, the figure format is "svg", and the embed mode is "raw". Example:

---
title: "D2 Example"
format: html
filters:
  - d2
d2:
  format: svg
  embed_mode: raw
---

```{.d2 width="40%"}
x { 
  link: "https://quarto.org"
}
y {
  tooltip: "This is a tooltip"
}
x -> y -> z
```