/// <summary>
/// Creates a new instance of the <see cref="ImageBuilder"/> class.
/// </summary>
public ImageBuilder()
{
_drawFormat = new StringFormat();
_drawFormat.Alignment = StringAlignment.Center;
_unit = BarCodeUnit.Inch;
_dpi = UnitConverter.ScreenDpi;
}
/// <summary>
/// Converts and stores the settings' convertible properties to another unit of measure.
/// </summary>
/// <param name="fromUnit">The unit the settings properties are.</param>
/// <param name="toUnit">the unit to convert to.</param>
public void ConvertValues(BarCodeUnit fromUnit, BarCodeUnit toUnit)
{
int dpi = _settings.Dpi;
_settings.BarHeight = UnitConverter.Convert(_settings.BarHeight, fromUnit, toUnit, dpi);
_settings.GuardExtraHeight = UnitConverter.Convert(_settings.GuardExtraHeight, fromUnit, toUnit, dpi);
_settings.ModuleWidth = UnitConverter.Convert(_settings.ModuleWidth, fromUnit, toUnit, dpi);
_settings.NarrowWidth = UnitConverter.Convert(_settings.NarrowWidth, fromUnit, toUnit, dpi);
_settings.WideWidth = UnitConverter.Convert(_settings.WideWidth, fromUnit, toUnit, dpi);
_settings.OffsetHeight = UnitConverter.Convert(_settings.OffsetHeight, fromUnit, toUnit, dpi);
_settings.OffsetWidth = UnitConverter.Convert(_settings.OffsetWidth, fromUnit, toUnit, dpi);
}
/// <summary>
/// Convert a value to another DPI.
/// If the value is in a non-pixel unit, the same value is returned to maintain the aspect ratio.
/// </summary>
/// <param name="value">Value to convert.</param>
/// <param name="unit">Value unit.</param>
/// <param name="fromDpi">The current DPI of the value.</param>
/// <param name="toDpi">The target DPI for conversion.</param>
/// <returns>The value in the new DPI.</returns>
public static float ConvertDpi(float value, BarCodeUnit unit, int fromDpi, int toDpi)
{
if (fromDpi <= 0 || toDpi <= 0)
{
throw new ArgumentException("DPIs must be greater than zero.");
}
if (unit != BarCodeUnit.Pixel)
{
return(value);
}
var ratio = toDpi / (float)fromDpi;
return(value * ratio);
}
/// <summary>
/// Converts a value between measuring units.
/// </summary>
/// <param name="value">Value to be converted.</param>
/// <param name="sourceUnit">The unit to convert from.</param>
/// <param name="targetUnit">The unit to convert to.</param>
/// <param name="dpi">The DPI to use.</param>
/// <returns>The converted unit.</returns>
public static float Convert(float value, BarCodeUnit sourceUnit, BarCodeUnit targetUnit, int dpi)
{
if (dpi <= 0)
{
throw new ArgumentException("DPI must be greater than zero.");
}
if (sourceUnit == targetUnit)
{
return(value);
}
// keep track of the value being converted
float converted = value;
int sourceUnitIndex = (int)sourceUnit;
if (sourceUnit == BarCodeUnit.Pixel)
{
// convert the value from pixels to inches
converted /= dpi;
sourceUnitIndex = (int)BarCodeUnit.Inch;
}
int targetUnitIndex = (int)targetUnit;
if (targetUnit == BarCodeUnit.Pixel)
{
// apply the inch to pixel ratio (the DPI)
converted *= dpi;
// convert to inches rather than to pixels
targetUnitIndex = (int)BarCodeUnit.Inch;
}
converted *= ConversionTable [sourceUnitIndex, targetUnitIndex];
return(converted);
}