icns

commit e6262f6023aba2df14b9f86976dcf57364f33acc
parent a57a0acee894cdc0975d74bba1cbb995fbf5e2f5
Author: Jack Mordaunt <jackmordaunt@gmail.com>
Date:   Sat, 17 Feb 2018 23:48:29 +0100

[*] Expanded the OsType to associate the types with their sizes.

Diffstat:
M
icns.go
 | 
57
+++++++++++++++++++++++++++++++++++----------------------
M
writer.go
 | 
8
++++----

2 files changed, 39 insertions(+), 26 deletions(-)
diff --git a/icns.go b/icns.go
@@ -71,7 +71,7 @@ func NewIconSet(img image.Image, interp InterpolationFunction, format string) (*
 	}
 	icons := []*Icon{}
 	for _, size := range sizesFrom(biggest) {
-		t, ok := getType(size)
+		t, ok := getTypeFromSize(size)
 		if !ok {
 			continue
 		}
@@ -139,28 +139,41 @@ func sizesFrom(max uint) []uint {
 }
 
 // OsType is a 4 character identifier used to differentiate icon types.
-type OsType string
+type OsType struct {
+	ID   string
+	Size uint
+}
+
+var osTypes = []OsType{
+	{ID: "ic10", Size: uint(1024)},
+	{ID: "ic14", Size: uint(512)},
+	{ID: "ic13", Size: uint(256)},
+	{ID: "ic07", Size: uint(128)},
+	{ID: "ic12", Size: uint(64)},
+	{ID: "ic11", Size: uint(32)},
+}
 
-// getType returns the type for the given icon size (in px).
+// getTypeFromSize returns the type for the given icon size (in px).
 // The boolean indicates whether the type exists.
-func getType(size uint) (OsType, bool) {
-	// 'types' is a map of the OSTypes we care about.
-	// All dimensions are considered as retina.
-	//
-	// Todo(jackmordaunt): Not sure if only retina is sufficient. Should all
-	// types be handled? `iconutil` uses file names to determine whether a
-	// retina image is desired eg: "icon_256x256@2.png", without such a hint
-	// how can you disambiguate 256x256 standard vs 256x256 retina?
-	// Do we even need to consider standard sizes over retina?
-	// For now, just retina types are considered.
-	types := map[uint]OsType{
-		1024: "ic10",
-		512:  "ic14",
-		256:  "ic13",
-		128:  "ic07",
-		64:   "ic12",
-		32:   "ic11",
+func getTypeFromSize(size uint) (OsType, bool) {
+	for _, t := range osTypes {
+		if t.Size == size {
+			return t, true
+		}
+	}
+	return OsType{}, false
+}
+
+func getTypeFromID(ID string) (OsType, bool) {
+	for _, t := range osTypes {
+		if t.ID == ID {
+			return t, true
+		}
 	}
-	v, ok := types[size]
-	return v, ok
+	return OsType{}, false
+}
+
+func osTypeFromID(ID string) OsType {
+	t, _ := getTypeFromID(ID)
+	return t
 }
diff --git a/writer.go b/writer.go
@@ -68,10 +68,10 @@ func encodeImage(img image.Image, format string) ([]byte, error) {
 func (i *Icon) writeHeader(wr io.Writer) (int64, error) {
 	if !i.headerSet {
 		defer func() { i.headerSet = true }()
-		i.header[0] = i.Type[0]
-		i.header[1] = i.Type[1]
-		i.header[2] = i.Type[2]
-		i.header[3] = i.Type[3]
+		i.header[0] = i.Type.ID[0]
+		i.header[1] = i.Type.ID[1]
+		i.header[2] = i.Type.ID[2]
+		i.header[3] = i.Type.ID[3]
 		length := uint32(len(i.data) + 8)
 		writeUint32(i.header[4:8], length)
 	}