Renamed option -m to -c and changed semantics

README.md

@@ -29,7 +29,7 @@ To install
   - **`-t`** : luma threshold (0.0 to 1.0)
   - **`-l`** : use BT.701 luma function instead of BT.601 to give more
     weight to red and blue
-  - **`-m`** : create monochrome
+  - **`-c`** : use average color for area rather than just black (default true)
 
 Example usages
 

main.go

@@ -32,7 +32,7 @@ var (
 	outputFile    = flag.String("o", "", "Output file")
 	boxSize       = flag.Int("b", 50, "Box size for dots")
 	lumaThreshold = flag.Float64("t", 1.0, "Luma threshold - don't draw dots above this luminescence value.  Value from 0.0 to 1.0")
-	mono          = flag.Bool("m", false, "Set image to monochrome")
+	color         = flag.Bool("c", true, "Use average color for area rather than just black")
 	bt701         = flag.Bool("l", false, "Use BT.701 instead of BT.601 for luma calculations")
 )
 
@@ -71,7 +71,7 @@ func lumaBT601(r uint32, g uint32, b uint32) float64 {
 // makeDots creates dots whose diameter is proportional to the
 // luminance and color is the average color of the area in the image
 // they represent.
-func makeDots(img image.Image, boxSize int, lumaThreshold float64, mono bool, bt709 bool, outputFileName string) {
+func makeDots(img image.Image, boxSize int, lumaThreshold float64, color bool, bt709 bool, outputFileName string) {
 	// Create the output file
 	svgFile, err := os.Create(outputFileName)
 	if err != nil {
@@ -138,7 +138,7 @@ func makeDots(img image.Image, boxSize int, lumaThreshold float64, mono bool, bt
 				continue
 			}
 
-			if mono {
+			if color {
 				canvas.Circle((x*boxSize)+boxHalf, (y*boxSize)+boxHalf, int((1.0-luma)*float64(boxHalf)), "fill:black;stroke:none")
 			} else {
 				canvas.Circle((x*boxSize)+boxHalf, (y*boxSize)+boxHalf, int((1.0-luma)*float64(boxHalf)), fmt.Sprintf("fill:#%02x%02x%02x;stroke:none", rSum, gSum, bSum))
@@ -169,5 +169,5 @@ func main() {
 		outputFile = &fn
 	}
 
-	makeDots(img, *boxSize, *lumaThreshold, *mono, *bt701, *outputFile)
+	makeDots(img, *boxSize, *lumaThreshold, *color, *bt701, *outputFile)
 }