gg/README.md

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# Go Graphics
`gg` is a library for rendering 2D graphics in pure Go.
## Installation
go get github.com/fogleman/gg
## Hello, Circle!
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Look how easy!
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```go
package main
import "github.com/fogleman/gg"
func main() {
dc := gg.NewContext(1000, 1000)
dc.DrawCircle(500, 500, 400)
dc.SetRGB(0, 0, 0)
dc.SetLineWidth(10)
dc.Stroke()
dc.SavePNG("out.png")
}
```
## Drawing Functions
Ever used a graphics library that didn't have functions for drawing rectangles
or circles? What a pain!
```go
DrawLine(x1, y1, x2, y2 float64)
DrawRectangle(x, y, w, h float64)
DrawEllipticalArc(x, y, rx, ry, angle1, angle2 float64)
DrawEllipse(x, y, rx, ry float64)
DrawArc(x, y, r, angle1, angle2 float64)
DrawCircle(x, y, r float64)
DrawImage(im image.Image, x, y int)
DrawString(x, y float64, s string)
MoveTo(x, y float64)
LineTo(x, y float64)
QuadraticTo(x1, y1, x2, y2 float64)
ClosePath()
ClearPath()
Clear()
Stroke()
Fill()
StrokePreserve()
FillPreserve()
```
## Color Functions
Colors can be set in several different ways for your convenience.
```go
SetColor(c color.Color)
SetHexColor(x string)
SetRGBA255(r, g, b, a int)
SetRGB255(r, g, b int)
SetRGBA(r, g, b, a float64)
SetRGB(r, g, b float64)
```
## Transformation Functions
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All the usual matrix transformations are available too.
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```go
Identity()
Translate(x, y float64)
Scale(x, y float64)
Rotate(angle float64)
RotateAbout(angle, x, y float64)
Shear(x, y float64)
TransformPoint(x, y float64) (tx, ty float64)
Push()
Pop()
```