func run(t *time.Time) error {
// Make the image grid.
m := make([][]image.Image, depth)
for i := range m {
m[i] = make([]image.Image, depth)
}
// Download images in parallel. Woo go!
log.Println("Starting download...")
startTime := time.Now()
var wg sync.WaitGroup
var err error
for i := 0; i < depth; i++ {
for j := 0; j < depth; j++ {
wg.Add(1)
go func(i, j int) {
defer wg.Done()
m[i][j], err = himawari.GridAt(t, depth, i, j)
}(i, j)
}
}
wg.Wait()
log.Printf("Done! Downloading images took %s.\n", time.Now().Sub(startTime))
// Join the pieces and set the background image.
// A depth=20 crashed my VM around this part, so watch out.
var img image.Image
img = background.Join(m, gridSize*depth, gridSize*depth)
img = background.Expand(img, 16/9) // FIXME
log.Println("Setting image as background...")
return background.Set(img)
}
func main() {
flag.Parse()
// Set the satellite.
var dl download.Downloader
switch satellite {
case "himawari":
dl = download.Himawari{Depth: depth}
case "dscovr":
dl = download.Dscovr{}
default:
log.Fatalln("Satellite not recognized. Exiting.")
}
// Start off with a zero time.
for lastTime := (time.Time{}); ; time.Sleep(every) {
// Get the filename to the latest image.
filename, err := dl.ModifiedSince(lastTime)
if err != nil {
log.Println(err)
continue
}
if filename == "" {
log.Println("No changes since last time. Trying again later...")
continue
}
// There is new image out. Download it.
log.Println("Starting download...")
benchmarkTime := time.Now()
img, err := dl.Download(filename)
if err != nil {
log.Println(err)
continue
}
log.Printf("Done! Download took %s.\n", time.Now().Sub(benchmarkTime))
// Set the image as the background.
// This one's a serious error, so break if it happens.
log.Println("Setting image as background...")
if err := background.Set(img); err != nil {
log.Println(err)
break
}
// Success. Replace lastTime with the current time.
lastTime = time.Now()
// If we're only doing this once, quit.
if every == 0 {
break
}
}
}