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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!
+
+```go
+package main
+
+import "github.com/fogleman/gg"
+
+func main() {
+    // create a new 1000x1000 pixel image
+    dc := gg.NewContext(1000, 1000)
+
+    // draw a circle at the center with radius 400
+    // nothing is drawn yet, we have to call Stroke or Fill
+    dc.DrawCircle(500, 500, 400)
+
+    // use black and 10px stroke width
+    dc.SetRGB(0, 0, 0)
+    dc.SetLineWidth(10)
+    dc.Stroke()
+
+    // write the result to file
+    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
+
+```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()
+```