69 lines
2.3 KiB
Go
69 lines
2.3 KiB
Go
// Copyright 2010 The draw2d Authors. All rights reserved.
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// created: 13/12/2010 by Laurent Le Goff
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// Package draw2d is a pure go 2D vector graphics library with support
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// for multiple output devices such as images (draw2d), pdf documents
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// (draw2dpdf) and opengl (draw2dopengl), which can also be used on the
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// google app engine.
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//
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// Features
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//
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// Operations in draw2d include stroking and filling polygons, arcs,
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// Bézier curves, drawing images and text rendering with truetype fonts.
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// All drawing operations can be transformed by affine transformations
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// (scale, rotation, translation).
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//
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// Installation
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//
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// To install or update the package on your system, run:
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// go get -u github.com/llgcode/draw2d
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//
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// Quick Start
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//
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// Package draw2d itself provides a graphic context that can draw vector
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// graphics and text on an image canvas. The following Go code
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// generates a simple drawing and saves it to an image file:
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// // Initialize the graphic context on an RGBA image
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// dest := image.NewRGBA(image.Rect(0, 0, 297, 210.0))
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// gc := draw2d.NewGraphicContext(dest)
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//
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// // Set some properties
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// gc.SetFillColor(color.RGBA{0x44, 0xff, 0x44, 0xff})
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// gc.SetStrokeColor(color.RGBA{0x44, 0x44, 0x44, 0xff})
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// gc.SetLineWidth(5)
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//
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// // Draw a closed shape
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// gc.MoveTo(10, 10) // should always be called first for a new path
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// gc.LineTo(100, 50)
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// gc.QuadCurveTo(100, 10, 10, 10)
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// gc.Close()
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// gc.FillStroke()
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//
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// // Save to file
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// draw2d.SaveToPngFile(fn, dest)
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//
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// There are more examples here:
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// https://github.com/llgcode/draw2d.samples
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//
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// Drawing on pdf documents is provided by the draw2dpdf package.
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// Drawing on opengl is provided by the draw2dgl package.
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// See subdirectories at the bottom of this page.
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//
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// Acknowledgments
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//
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// Laurent Le Goff wrote this library, inspired by postscript and
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// HTML5 canvas. He implemented the image and opengl backend. Also
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// he created a pure go Postscripter interpreter which can draw to a
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// draw2d graphic context (https://github.com/llgcode/ps). Stani
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// Michiels implemented the pdf backend.
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//
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// The package depends on freetype-go package for its rasterization
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// algorithm.
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//
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// Packages using draw2d
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//
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// - https://github.com/llgcode/ps
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//
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// - https://github.com/gonum/plot
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package draw2d
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