recording

README

Recording System Example

This example demonstrates the recording system for vector export.

What it does

1. Creates a Recorder to capture drawing operations
2. Draws various shapes: gradient background, circle, rounded rectangle, dashed line, rotated square
3. Exports to multiple formats: PNG (raster), PDF, SVG

Running

Raster only (no additional dependencies)

go run main.go

Output: output.png

With PDF export

go get github.com/gogpu/gg-pdf

Then uncomment the import in main.go:

_ "github.com/gogpu/gg-pdf"

Output: output.png, output.pdf

With SVG export

go get github.com/gogpu/gg-svg

Then uncomment the import in main.go:

_ "github.com/gogpu/gg-svg"

Output: output.png, output.svg

Key Concepts

Recording

rec := recording.NewRecorder(width, height)
// Draw using familiar API...
r := rec.Finish()

Playback

backend, _ := recording.NewBackend("pdf")
r.Playback(backend)
backend.(recording.FileBackend).SaveToFile("output.pdf")

Backend Registration

Backends are registered via blank imports (like database/sql drivers):

import _ "github.com/gogpu/gg-pdf"  // Registers "pdf"
import _ "github.com/gogpu/gg-svg"  // Registers "svg"

Output

The example produces a 400x300 image with:

• Gradient background (dark blue to light blue)
• Red circle
• White rounded rectangle (stroked)
• Yellow dashed line
• Green rotated square with transparency

Documentation

Overview

Example: Recording System

This example demonstrates the recording system for vector export. It creates a drawing, records it, and exports to multiple formats.

To run with PDF/SVG export, you need the backend packages:

go get github.com/gogpu/gg-pdf
go get github.com/gogpu/gg-svg

Then uncomment the relevant import lines below.