skia2/experimental/go-demo/main.go
Stephan Altmueller efa48d599d Experimental Go bindings for Skia
This CL implements Go bindings for a subset of the functions in the C API. 
It implements a Go version of the C demo program in 
experimental/c-api-example/skia-c-example.c and the output is identical. 
(Checked by hand). 

The main purpose is to establish a pattern of calling the Skia C API that 
is memory safe and provides a idiomatic Go interface to Skia. 

Follow up CLs will cover the entire C API, add documentation and establish 
a pattern to distribute the bindings more easily.

BUG=
Change-Id: I96ff7c3715164c533202ce300ab0312b1b07f884

Change-Id: I96ff7c3715164c533202ce300ab0312b1b07f884
Reviewed-on: https://skia-review.googlesource.com/10032
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Stephan Altmueller <stephana@google.com>
2017-05-10 15:32:19 +00:00

77 lines
1.6 KiB
Go

/*
* Copyright 2015 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
package main
/*
This is a translation of the example code in
"experimental/c-api-example/skia-c-example.c" to test the
go-skia package.
*/
import (
"log"
"os"
skia "skia.googlesource.com/skia/experimental/go-skia"
)
func main() {
imgInfo := &skia.ImageInfo{
Width: 640,
Height: 480,
ColorType: skia.GetDefaultColortype(),
AlphaType: skia.PREMUL_ALPHATYPE,
}
surface, err := skia.NewRasterSurface(imgInfo)
if err != nil {
log.Fatalln(err)
}
canvas := surface.Canvas()
fillPaint := skia.NewPaint()
fillPaint.SetColor(0xFF0000FF)
canvas.DrawPaint(fillPaint)
fillPaint.SetColor(0xFF00FFFF)
rect := skia.NewRect(100, 100, 540, 380)
canvas.DrawRect(rect, fillPaint)
strokePaint := skia.NewPaint()
strokePaint.SetColor(0xFFFF0000)
strokePaint.SetAntiAlias(true)
strokePaint.SetStroke(true)
strokePaint.SetStrokeWidth(5.0)
path := skia.NewPath()
path.MoveTo(50, 50)
path.LineTo(590, 50)
path.CubicTo(-490, 50, 1130, 430, 50, 430)
path.LineTo(590, 430)
canvas.DrawPath(path, strokePaint)
fillPaint.SetColor(0x8000FF00)
canvas.DrawOval(skia.NewRect(120, 120, 520, 360), fillPaint)
// // Get a skia image from the surface.
skImg := surface.Image()
// Write new image to file if we have one.
if skImg != nil {
out, err := os.Create("testimage.png")
if err != nil {
log.Fatal(err)
}
defer out.Close()
if err := skImg.WritePNG(out); err != nil {
log.Fatalf("Unable to write png: %s", err)
}
}
}