small fixes

assets/loader-sprites.go

@@ -44,8 +44,8 @@ type AnimationMeta struct {
 
 // Needed to thaw sprite set written by asesprite
 type AnimationJSON struct {
-	Meta   AnimationMeta    `json:"Meta"`
-	Frames []AnimationFrame `json:"frames"`
+	Meta   AnimationMeta             `json:"Meta"`
+	Frames map[string]AnimationFrame `json:"frames"`
 }
 
 // used to store Animation data
@@ -133,7 +133,7 @@ func ReadJson(imagefile fs.DirEntry, fd fs.File) AnimationJSON {
 
 	err := json.Unmarshal(buf.Bytes(), &animationjson)
 	if err != nil {
-		log.Fatalf("failed to parse JSON: %s", err)
+		log.Fatalf("failed to parse JSON in %s: %s", imagefile, err)
 	}
 
 	return animationjson