Duotone Gradient Mapping [v2 2023-04-22]

[pascal]

[April 22th 2023] Version 2 available!

 

Back with my second plugin. This time I made a plugin that can be used to easily and quickly create a gradient mapping effect using 2 colors. I know pyrochild already made a gradient mapping tool, but this is just a simplified version using only 2 colors for dark and light tones. I added some options for post processing as well, like contrast and blending mode.

 

 

Download

Location: Effects > Color > Duotone Gradient Map

duotonegradientmap.zip

 

Code

Spoiler

#region UICode
ColorWheelControl DARK = ColorBgra.FromBgr(0, 0, 0); // Dark
ColorWheelControl LIGHT = ColorBgra.FromBgr(255, 255, 255); // Light
IntSliderControl CONTRAST = 0; // [-100,100] Contrast
ListBoxControl<BlendMode> BLEND = 0; // Blending mode|Normal
IntSliderControl MIX = 100; // [0,100] Mix
#endregion
enum BlendMode
{
    Normal, Multiply, Screen, Darken, Lighten, Overlay, Additive
}

Func<byte, byte, byte> blender = null;

void PreRender(Surface dst, Surface src)
{
    blender = BLEND switch
        {
            BlendMode.Multiply => BlendMult,
            BlendMode.Screen => BlendScreen,
            BlendMode.Darken => BlendDarken,
            BlendMode.Lighten => BlendLighten,
            BlendMode.Overlay => BlendOverlay,
            BlendMode.Additive => BlendAdd,
            _ => BlendNormal
        };
}

void Render(Surface dst, Surface src, Rectangle rect)
{
    double mix = MIX / 100.0;
    double contrast = CONTRAST / 10.0;
    
    ColorBgra c;
    for (int y = rect.Top; y < rect.Bottom; y++)
    {
        if (IsCancelRequested) return;
        for (int x = rect.Left; x < rect.Right; x++)
        {
            c = src[x,y];
            double value = Contrast((c.R + c.G + c.B) / 765.0, contrast);
            ColorBgra n = Mix(DARK, LIGHT, value);
            n = ApplyBlend(c, n, blender);
            n = Mix(c, n, mix);
            n.A = c.A;
            dst[x,y] = n;
        }
    }
}

double Contrast(double x, double p)
{
    if (p == 0)
    {
        return x;
    }
    if (p > 0)
    {
        return x < 0.5
            ? 0.5 * Math.Pow(2.0 * x, p + 1.0)
            : 1.0 - 0.5 * Math.Pow(2.0 - 2.0 * x, p + 1.0);
    }
    else {
        return x < 0.5
            ? 0.5 - 0.5 * Math.Pow(1.0 - 2.0 * x, 1.0 - p)
            : 0.5 + 0.5 * Math.Pow(2.0 * x - 1.0, 1.0 - p);
    }
}

ColorBgra Mix(ColorBgra a, ColorBgra b, double value)
{
    return ColorBgra.FromBgr(
        Mix(a.B, b.B, value),
        Mix(a.G, b.G, value),
        Mix(a.R, b.R, value)
    );
}

byte Mix(byte a, byte b, double value)
{
    double output = (1.0 - value) * a + value * b;
    return (byte) Math.Clamp(output, 0.0, 255.0);
}

ColorBgra ApplyBlend(ColorBgra a, ColorBgra b, Func<byte, byte, byte> f)
{
    return ColorBgra.FromBgr(
        f(a.B, b.B), 
        f(a.G, b.G),
        f(a.R, b.R)
    );
}

byte BlendNormal(byte a, byte b)
{
    return b;
}

byte BlendDarken(byte a, byte b)
{
    return Math.Min(a, b);
}

byte BlendLighten(byte a, byte b)
{
    return Math.Max(a, b);
}

byte BlendMult(byte a, byte b)
{
    return (byte) Math.Clamp(a * b * 0.0039215686, 0.0, 255.0);
}

byte BlendScreen(byte a, byte b)
{
    return (byte) (255 - BlendMult((byte) (255 - a), (byte) (255 - b)));
}

byte BlendOverlay(byte a, byte b)
{
    return (byte) (a < 127
        ? 2 * BlendMult(a, b)
        : 2 * BlendScreen(a, b));
}

byte BlendAdd(byte a, byte b)
{
    return (byte) Math.Clamp(a + b, 0, 255);
}

 

Edited April 22, 2023 by pascal
effect location

[Ego Eram Reputo]

//BLENDING MODES

            //multiply
            if(M == 1){

You could clean up the code using Switch /Case for these tests.

 

      switch (M)
      {
          case 1:
              //Console.WriteLine("Case 1");
              break;
          case 2:
              //Console.WriteLine("Case 2");
              break;
          
          ...
            
          default:
              //Console.WriteLine("Default case");
              break;
      }

 

It's not a big thing - but BoltBait & toe_head2001 have got some awesome coloring effects for sliders baked right into Codelab. They look really cool

[toe_head2001]

1 hour ago, Ego Eram Reputo said:

You could clean up the code using Switch /Case for these tests.

 

Using an enum is even cleaner.

#region UICode
ListBoxControl<BlendingMode> blendingMode = 0; // Blending mode|Normal|Multiply|Darken|Lighten|Additive
#endregion

enum BlendingMode
{
    Normal,
    Multiply,
    Darken,
    Lighten,
    Additive
}

void Render(Surface dst, Surface src, Rectangle rect)
{
    switch (blendingMode)
    {
        case BlendingMode.Multiply:
            // code here
            break;

        case BlendingMode.Darken:
            // code here
            break;

        case BlendingMode.Lighten:
            // code here
            break;

        case BlendingMode.Additive:
            // code here
            break;

        case BlendingMode.Normal:
        default:
            // code here
            break;
    }
}

 

[TrevorOutlaw]

I wanted to make a plugin very similar to this at one time. Awesome plugin!

[Vagabondi]

Works like charm @pascal. Endless possibilities to recolor photo - and very good settings.

 

[Panchdara]

@pascal - Nice. Whilst the "suggestions" are constructive, you've built some code that can be used. There's always a critic. Your code is entirely readable. Stick with what you feel comfortable with.

[pascal]

Version 2 available

- Changed the layout to make it more clear in which order things are applied.

- Contrast now only applies to the color-mapped layer.

- Added more blending modes.

- Made the mix slider independent of blending modes.

- Improved overall code.