/// <summary>
/// Tries to increase a component of the 16-bit color by the given value,
/// starting from the green component with the highest value range.
/// </summary>
/// <param name="color">The 16-bit color to increase.</param>
/// <param name="value">The value of how much to attempt to increase a component.</param>
/// <returns>True if any of the components could be increased by the given value,
/// false otherwise.</returns>
private static bool TryIncrease(ref Color565 color, int value)
{
const int maxValue6Bit = 63;
const int maxValue5Bit = 31;
if (color.G + value > 0 &&
color.G + value <= maxValue6Bit)
{
color = Color565.FromRgb(color.R, color.G + value, color.B);
return(true);
}
if (color.R + value > 0 &&
color.R + value <= maxValue5Bit)
{
color = Color565.FromRgb(color.R + value, color.G, color.B);
return(true);
}
if (color.B + value > 0 &&
color.B + value <= maxValue5Bit)
{
color = Color565.FromRgb(color.R, color.G, color.B + value);
return(true);
}
return(false);
}
public void ConstructFromBytes()
{
var color = Color565.FromRgb((byte)10, (byte)51, (byte)23);
Assert.AreEqual(10, color.R);
Assert.AreEqual(51, color.G);
Assert.AreEqual(23, color.B);
}
/// <summary>
/// Converts the 32-bit color into a 16-bit R5:G6:B5 color by shifting the bits right for
/// each color component.
/// </summary>
public static Color565 To16Bit(Color color)
{
int r = color.R >> 3;
int g = color.G >> 2;
int b = color.B >> 3;
return(Color565.FromRgb(r, g, b));
}
/// <summary>
/// Blends the two colors by taking the average of each color component.
/// </summary>
public static Color565 Blend(Color565 a, Color565 b)
{
var c = BlendComponents(
new[] { a.R, a.G, a.B },
new[] { b.R, b.G, b.B });
return(Color565.FromRgb(c[0], c[1], c[2]));
}
public void ConstructFrom32BitIntegers()
{
var color = Color565.FromRgb(10, 51, 23);
Assert.AreEqual(10, color.R);
Assert.AreEqual(51, color.G);
Assert.AreEqual(23, color.B);
}
/// <summary>
/// Linearly interpolates to two thirds of the distance from the
/// first color to the second color for each color component.
/// </summary>
public static Color565 LerpTwoThirds(Color565 a, Color565 b)
{
var c = LerpComponents(
new[] { a.R, a.G, a.B },
new[] { b.R, b.G, b.B });
return(Color565.FromRgb(c[0], c[1], c[2]));
}
public void Blend16BitColors()
{
var a = Color565.FromRgb(30, 60, 20);
var b = Color565.FromRgb(20, 60, 25);
var expected = Color565.FromRgb(25, 60, 23);
var result = ColorUtility.Blend(a, b);
Assert.AreEqual(expected, result);
}
public void Lerp16BitColors()
{
var a = Color565.FromRgb(10, 60, 20);
var b = Color565.FromRgb(30, 60, 15);
var expected = Color565.FromRgb(23, 60, 17);
var result = ColorUtility.LerpTwoThirds(a, b);
Assert.AreEqual(expected, result);
}
public void DifferentiationDecreasesMinColorByOneWhenMaxCannotBeIncreased()
{
var minOriginal = Color565.FromRgb(31, 63, 31);
var maxOriginal = Color565.FromRgb(31, 63, 31);
var min = minOriginal;
var max = maxOriginal;
ColorUtility.TryDifferentiateByOne(ref min, ref max);
Assert.AreEqual(Color565.FromRgb(31, 62, 31), min);
Assert.AreEqual(maxOriginal, max);
}
public void DifferentiationIncreasesMaxColorByOneWhenMaxCanBeIncreased()
{
var minOriginal = Color565.FromRgb(15, 43, 9);
var maxOriginal = Color565.FromRgb(15, 43, 9);
var min = minOriginal;
var max = maxOriginal;
ColorUtility.TryDifferentiateByOne(ref min, ref max);
Assert.AreEqual(minOriginal, min);
Assert.AreEqual(Color565.FromRgb(15, 44, 9), max);
}
public void ConstructionClampsComponentsForBytes()
{
var expected = Color565.FromRgb((byte)31, (byte)63, (byte)31);
var color1 = Color565.FromRgb((byte)255, (byte)255, (byte)255);
var color2 = Color565.FromRgb((byte)150, (byte)230, (byte)130);
Assert.AreEqual(expected, color1);
Assert.AreEqual(expected, color2);
Assert.AreEqual(MaxValue16Bit, color1.Value);
Assert.AreEqual(MaxValue16Bit, color2.Value);
}
public void DifferentiationDoesNothingWhenColorsAreDifferent()
{
var minOriginal = Color565.FromRgb(15, 31, 21);
var maxOriginal = Color565.FromRgb(13, 24, 14);
var min = minOriginal;
var max = maxOriginal;
ColorUtility.TryDifferentiateByOne(ref min, ref max);
Assert.AreEqual(minOriginal, min);
Assert.AreEqual(maxOriginal, max);
}
public void CalculateDistanceBetween16BitColors()
{
var a = Color565.FromRgb(10, 16, 9);
var b = Color565.FromRgb(20, 63, 31);
var expected = Math.Sqrt((10 - 20) * (10 - 20) +
(16 - 63) * (16 - 63) +
(9 - 31) * (9 - 31));
var result = ColorUtility.Distance(a, b);
const double delta = 0.0001d;
Assert.AreEqual(expected, result, delta);
}
public void Convert32BitColorTo16Bit()
{
var color1 = Color.FromArgb(74, 207, 231);
var expected1 = Color565.FromRgb(9, 51, 28);
var color2 = Color.FromArgb(0, 255, 255);
var expected2 = Color565.FromRgb(0, 63, 31);
var result1 = ColorUtility.To16Bit(color1);
var result2 = ColorUtility.To16Bit(color2);
Assert.AreEqual(expected1, result1);
Assert.AreEqual(expected2, result2);
}
public void ConstructionClampsComponentsFor32BitIntegers()
{
var expected = Color565.FromRgb(31, 63, 31);
var color1 = Color565.FromRgb(3455, 23145, 55132);
var color2 = Color565.FromRgb(255, 255, 255);
var color3 = Color565.FromRgb(150, 230, 130);
Assert.AreEqual(expected, color1);
Assert.AreEqual(expected, color2);
Assert.AreEqual(expected, color3);
Assert.AreEqual(MaxValue16Bit, color1.Value);
Assert.AreEqual(MaxValue16Bit, color2.Value);
Assert.AreEqual(MaxValue16Bit, color3.Value);
}
public void FormatIsR5G6B5()
{
var color = Color565.FromRgb(10, 51, 23);
// 10 = _0 1010 -> R5
// 51 = 11 0011 -> G6
// 23 = _1 0111 -> B5
// R5 G6 B5
// 0101 0|110 011|1 0111 16-bit layout
const int expected = 22135;
var value = color.Value;
Assert.AreEqual(expected, value);
}
public void CalculateClosestColor()
{
var target = Color565.FromRgb(15, 31, 15);
var expected = Color565.FromRgb(13, 29, 14);
var colors = new []
{
Color565.FromRgb(0, 0, 0),
Color565.FromRgb(31, 63, 31),
Color565.FromRgb(9, 56, 45),
expected,
Color565.FromRgb(24, 45, 14),
};
var closest = ColorUtility.GetClosestColor(colors, target);
Assert.AreEqual(expected, closest);
}