icns

commit 4f16af745526e95b661c14f351d630f54bf55f0f
parent bcdb459e06604ebe066cebaa4f971bd68e2e0a70
Author: Jack Mordaunt <jackmordaunt@gmail.com>
Date:   Mon, 31 Dec 2018 21:59:25 +1300

[+] Create resized images in parallel.

Diffstat:
M
icns.go
 | 
24
++++++++++++++++--------
M
writer.go
 | 
3
+++

2 files changed, 19 insertions(+), 8 deletions(-)
diff --git a/icns.go b/icns.go
@@ -4,6 +4,7 @@ import (
 	"errors"
 	"image"
 	"io"
+	"sync"
 
 	"github.com/nfnt/resize"
 )
@@ -61,19 +62,26 @@ func NewIconSet(img image.Image, interp InterpolationFunction) (*IconSet, error)
 	if biggest == 0 {
 		return nil, ErrImageTooSmall{image: img, need: 16}
 	}
-	icons := []*Icon{}
-	for _, size := range sizesFrom(biggest) {
+	icons := make([]*Icon, len(osTypes))
+	work := sync.WaitGroup{}
+	for ii, size := range sizesFrom(biggest) {
 		t, ok := getTypeFromSize(size)
 		if !ok {
 			continue
 		}
-		iconImg := resize.Resize(size, size, img, interp)
-		icon := &Icon{
-			Type:  t,
-			Image: iconImg,
-		}
-		icons = append(icons, icon)
+		ii := ii
+		size := size
+		work.Add(1)
+		go func() {
+			iconImg := resize.Resize(size, size, img, interp)
+			icons[ii] = &Icon{
+				Type:  t,
+				Image: iconImg,
+			}
+			work.Done()
+		}()
 	}
+	work.Wait()
 	iconset := &IconSet{
 		Icons: icons,
 	}
diff --git a/writer.go b/writer.go
@@ -109,6 +109,9 @@ func (s *IconSet) encodeIcons() error {
 	}
 	buf := bytes.NewBuffer(nil)
 	for _, icon := range s.Icons {
+		if icon == nil {
+			continue
+		}
 		if _, err := icon.WriteTo(buf); err != nil {
 			return err
 		}