Added dimensions converter

src/main/java/w2phtml/util/DimensionsConverter.java

@@ -0,0 +1,59 @@
+package w2phtml.util;
+
+public class DimensionsConverter {
+
+	public static float pixelsPerInch = 96.0F;
+	public static final float length2px(String input, float ppi) {
+		if ( input.equals("0")) {
+			return 0;
+		}
+		if (ppi <= 0) {
+			ppi = pixelsPerInch;
+		}
+		String unit = input.replaceAll("[^a-zA-Z]", "");
+		String dimension = input.replaceAll("[^0-9.]", "");
+		float length = parseNumber(dimension, 0);
+		float pixels = ppi / getUnitsPerInch(unit) * length;
+		if (Math.abs(pixels) < 0.01) {
+			// Very small, treat as zero
+			return 0;
+		} else if (pixels > 0) {
+			// Never return less that 1px
+			return pixels < 1 ? 1 : pixels;
+		} else {
+			// Or above -1px
+			return pixels > -1 ? -1 : pixels;
+		}
+	}
+	
+	public static final float parseNumber(String input, float defaultValue) {
+		float result;
+		try {
+			result = Float.parseFloat(input);
+		} catch (NumberFormatException e) {
+			return defaultValue;
+		}
+		return result;
+	}
+
+	private static final float getUnitsPerInch(String unit) {
+		if (unit == null) {
+			unit = "";
+		}
+		switch (unit) {
+		case "in":
+			return 1.0F;
+		case "mm":
+			return 25.4F;
+		case "cm":
+			return 2.54F;
+		case "pc":
+			return 6F;
+		case "pt":
+			return 72F;
+		default:
+			return 72;
+		}
+	}
+
+}