example for github.com/sztanpet/sh1106

sh1106.go

package main

import (
	"image"
	"image/draw"
	"image/gif"
	"log"
	"os"
	"time"

	"github.com/nfnt/resize"
	"github.com/sztanpet/sh1106"
	"periph.io/x/periph/conn/gpio"
	"periph.io/x/periph/conn/gpio/gpioreg"
	"periph.io/x/periph/conn/i2c/i2creg"
	"periph.io/x/periph/host"
)

func main() {
	_, err := host.Init()
	if err != nil {
		panic(err)
	}
	// chk(err)

	resetPin := gpioreg.ByName("4")
	if resetPin == nil {
		panic("can't get reset pin")
	}

	resetPin.Out(gpio.High)
	time.Sleep(1 * time.Millisecond)
	resetPin.Out(gpio.Low)
	time.Sleep(10 * time.Millisecond)
	resetPin.Out(gpio.High)
	time.Sleep(10 * time.Millisecond)

	bus, err := i2creg.Open("")
	chk(err)
	dev, err := sh1106.NewI2C(bus, &sh1106.DefaultOpts)
	chk(err)

	// Decodes an animated GIF as specified on the command line:
	if len(os.Args) != 2 {
		log.Fatal("please provide the path to an animated GIF")
	}
	f, err := os.Open(os.Args[1])
	chk(err)
	g, err := gif.DecodeAll(f)
	f.Close()
	chk(err)

	// Converts every frame to image.Gray and resize them:
	imgs := make([]*image.Gray, len(g.Image))
	w, h := dev.Bounds().Dx(), dev.Bounds().Dy()
	for i := range g.Image {
		imgs[i] = convertAndResizeAndCenter(w, h, g.Image[i])
	}

	// Display the frames in a loop:
	for i := 0; ; i++ {
		index := i % len(imgs)
		c := time.After(time.Duration(10*g.Delay[index]) * time.Millisecond)
		img := imgs[index]
		dev.Draw(img.Bounds(), img, image.Point{})
		<-c
	}
}

func convertAndResizeAndCenter(w, h int, src image.Image) *image.Gray {
	src = resize.Thumbnail(uint(w), uint(h), src, resize.Bicubic)
	img := image.NewGray(image.Rect(0, 0, w, h))
	r := src.Bounds()
	r = r.Add(image.Point{(w - r.Max.X) / 2, (h - r.Max.Y) / 2})
	draw.Draw(img, r, src, image.Point{}, draw.Src)
	return img
}

func chk(err error) {
	if err != nil {
		panic(err)
	}
}