predraw 0.1.1

Declarative rendering pipeline: JSON in, SVG/PNG/WebP out

predraw

Declarative rendering pipeline: JSON in, SVG/PNG/WebP out.

The missing link between your AI and the SVGs you want to make.

Install

uv tool install predraw

Quick start

Create a project directory:

my-asset/
  main.json
  config.json

main.json -- the scene:

{
  "width": 400,
  "height": 200,
  "styles": {
    "bg": {"light": "#ffffff", "dark": "#1a1a1a"},
    "fg": {"light": "#000000", "dark": "#ffffff"}
  },
  "elements": [
    {"type": "background", "fill": "$bg"},
    {
      "type": "text",
      "id": "title",
      "content": "hello world",
      "x": 200,
      "y": 110,
      "anchor": "middle",
      "fill": "$fg",
      "font": {"family": "Liberation Sans", "size": 48, "weight": 700}
    }
  ],
  "pipeline": [
    {"action": "text-to-paths", "target": "title"}
  ]
}

config.json -- output targets:

{
  "outputs": [
    {"format": "svg", "path": "hello-dark.svg", "mode": "dark"},
    {"format": "png", "path": "hello-light.png", "mode": "light"},
    {"format": "webp", "path": "hello-dark.webp", "mode": "dark", "quality": 90}
  ]
}

Build:

predraw build my-asset/

Commands

build [path]

Render all outputs defined in config.json. Path can be a directory (looks for main.json) or a file.

predraw build                    # current directory
predraw build path/to/project    # explicit path

pack [path] [-o file]

Convert a directory project into a single portable JSON file. Imports are resolved and inlined as defs.

predraw pack my-asset/ -o packed.json

unpack <file> [-o dir]

Convert a packed JSON file back into a directory project with separate component files.

predraw unpack packed.json -o my-asset/

Format

Element types

Type	Purpose	Key properties
background	Full-canvas fill	fill
rect	Rectangle	x, y, width, height, fill
path	SVG path	d, fill, opacity, transform
text	Text (can convert to paths)	content, font, anchor, charStyles
group	Container	elements, transform

Use (component instantiation)

Reference a component from imports or defs:

{"use": "logo", "transform": {"translate": [100, 50], "scale": [2, 2]}}

Property overrides cascade to children:

{"use": "logo", "fill": "#ff0000", "opacity": 0.5}

Styles

Define color tokens with light/dark variants:

{
  "styles": {
    "primary": {"light": "#000000", "dark": "#ffffff"},
    "muted": {"light": "#666666", "dark": "#999999"}
  }
}

Reference with $ prefix: "fill": "$primary". Mode is selected per-output in config.json.

charStyles

Style individual characters differently:

{
  "type": "text",
  "content": "releasable",
  "fill": "#ffffff",
  "charStyles": [
    {"chars": "rlsbl", "opacity": 1.0},
    {"chars": "eeaa", "opacity": 0.12}
  ]
}

Pipeline

Ordered postprocessing steps:

Action	Fields	Description
text-to-paths	target	Convert text to path outlines via font glyphs
center	target, axis (x/y/both)	Center element on canvas
place	target, below, gap	Position element below another
group	targets, id	Wrap elements into a group

Components

Split reusable parts into separate files:

project/
  main.json
  config.json
  components/
    logo.json

main.json:

{
  "imports": {"logo": "./components/logo.json"},
  "elements": [
    {"use": "logo", "transform": {"translate": [10, 10]}}
  ]
}

Packed format

predraw pack inlines imports as defs:

{
  "defs": {
    "logo": {"type": "group", "elements": [...]}
  },
  "elements": [
    {"use": "logo"}
  ]
}

Config

config.json defines output targets:

{
  "outputs": [
    {"format": "svg", "path": "out.svg"},
    {"format": "png", "path": "out-dark.png", "mode": "dark"},
    {"format": "webp", "path": "out.webp", "mode": "dark", "quality": 90}
  ]
}

Field	Required	Description
format	Yes	svg, png, or webp
path	Yes	Output file path (relative to project dir)
mode	No	light or dark (default: dark)
quality	No	WebP quality 1-100 (default: 90)

JSON Schema

Formal schemas for editor validation and LLM structured output:

• schema/scene.schema.json -- scene format
• schema/config.schema.json -- config format

Requirements

• Python 3.11+
• System fonts for text-to-paths (searches standard font directories)

License

MIT