Added verbose mode

Replaced hacky Sprintf/concat constructs with just Printf

main.go

@@ -13,7 +13,7 @@ import (
 )
 
 const (
-	version = "0.2"
+	version = "0.2.1"
 )
 
 func main() {
@@ -39,7 +39,7 @@ func main() {
 		os.Exit(1)
 	}
 
-	r := remapper.NewMapper(opts.MemoryHog)
+	r := remapper.NewMapper(opts.MemoryHog, opts.Verbose)
 
 	err = r.RemapFrames(opts.InputDir, opts.InputPattern, opts.OutputDir, opts.StartIndex)
 	if err != nil {

options.go

@@ -6,8 +6,8 @@ type CommandLineOpts struct {
 	InputPattern string `short:"p" long:"pattern" description:"Input file name glob pattern (optional)"`
 
 	StartIndex int `short:"s" long:"start-index" default:"0" description:"Starting index"`
-
 	MemoryHog bool `short:"M" long:"memory-hog" description:"Hog Mode (will attempt to keep all new frames in memory)"`
+	Verbose bool `short:"V" long:"verbose" description:"Outputs more status messages"`
 
 	Version  bool `short:"v" long:"version" description:"Show version and exit"`
 }

remapper/remapper.go

@@ -18,14 +18,15 @@ type Remapper struct {
 	inputFrames []string
 
 	frameWidth, frameHeight int
-	hogMode bool
+	hogMode, verbose bool
 }
 
-func NewMapper(hogMode bool) Remapper {
+func NewMapper(hogMode, verbose bool) Remapper {
 	r := Remapper{
 		frameWidth: -1,
 		frameHeight: -1,
 		hogMode: hogMode,
+		verbose: verbose,
 	}
 	return r
 }
@@ -127,13 +128,13 @@ func (r *Remapper) hogCheck() error {
 func (r *Remapper) RemapFrames(inputDir, inputPattern, outputDir string, startFrame int) error {
 	r.loadFilesWithPattern(inputDir, inputPattern)
 
-	fmt.Println("preflight check")
+	fmt.Println("Preflight check…")
 	err := r.preflightCheck()
 	if err != nil {
 		return err
 	}
 
-	fmt.Println("hog check")
+	fmt.Println("Hog check…")
 	err = r.hogCheck()
 	if err != nil {
 		// This is the one non-critical error here, so we merely print it instead of panicking
@@ -142,12 +143,20 @@ func (r *Remapper) RemapFrames(inputDir, inputPattern, outputDir string, startFr
 
 	inputFrameCache := make([]image.Image, len(r.inputFrames))
 
+	numDigits := len(strconv.Itoa(r.frameWidth))
+
 	// there will be as many new frames as pixels the input frames are wide
 	for frameX := startFrame; frameX < r.frameWidth; frameX++ {
 		// new frames are as high as the input frames
 		// but as wide as the total number of input frames
 		img := image.NewRGBA(image.Rect(0, 0, len(r.inputFrames), r.frameHeight))
 
+		fmt.Printf("Building frame %0[3]*[1]d/%0[3]*[2]d…\n", frameX+1, r.frameWidth, numDigits)
+
+		if r.hogMode && frameX == 0 {
+			fmt.Println("(Subsequent frames will be processed much faster)")
+		}
+
 		percent := -1
 
 		// loop through input frames and fill new frames with 1px-wide pixel columns
@@ -185,21 +194,25 @@ func (r *Remapper) RemapFrames(inputDir, inputPattern, outputDir string, startFr
 			newPercent := int(math.Floor(float64(dstX) / float64(len(r.inputFrames)) * 100))
 			if newPercent >= percent+1 {
 				percent = newPercent
-				fmt.Printf("%03d%% (%d/%d)\n",
-					newPercent,
-					dstX,
-					len(r.inputFrames))
+				if r.verbose {
+					fmt.Printf("%03[1]d%% (%0[4]*[2]d/%0[4]*[3]d)\n",
+						newPercent,
+						dstX, len(r.inputFrames),
+						numDigits)
+				}
 			}
 		}
 
-		fmt.Printf("%03d%% (%d/%d)\n",
-			100,
-			len(r.inputFrames),
-			len(r.inputFrames))
+		if r.verbose {
+			fmt.Printf("%03[1]d%% (%0[4]*[2]d/%0[4]*[3]d)\n",
+				100,
+				len(r.inputFrames), len(r.inputFrames),
+				numDigits)
+		}
 
-		formatStr := fmt.Sprintf("frame%%0%dd.png", len(strconv.Itoa(r.frameWidth)))
-		newFileName := filepath.Join(outputDir, fmt.Sprintf(formatStr, frameX))
-		newFrameFile, err := os.Create(newFileName)
+		newFileName := fmt.Sprintf("frame%0[2]*[1]d.png", frameX, numDigits)
+		newFilePath := filepath.Join(outputDir, newFileName)
+		newFrameFile, err := os.Create(newFilePath)
 		if err != nil {
 			return err
 		}