1. // A simple Halftone shader
    2. // Halftone.osl, by Zap Andersson
    3. // Modified: 2019-11-25
    4. // Modified: 202-1-11 by Saul Espinosa for Redshift 3D
    5. // Copyright 2019 Autodesk Inc, All rights reserved. This file is licensed under Apache 2.0 license
    6. //    https://github.com/ADN-DevTech/3dsMax-OSL-Shaders/blob/master/LICENSE.txt
    8. shader HalftoneDots
    9.     [[ string help="Halftone Dots (by default i screen space)<br>"
    10.                    "Works well together with toon shaders.",
    11.        string category = "Textures",
    12.        string label = "Halftone Dots" ]] 
    13. (
    14.     // Inputs
    15.     vector UVW   = transform("raster", P)
    16.         [[ string help = "The input coordinate. If not connected, uses screen pixel space" ]],
    17.     vector Scale = vector(8.0,8.0,8.0)
    18.         [[ string help = "This size of the dots. In the default screen space mapping, this is in pixels." ]],
    19.     float  Angle = 45.0
    20.         [[ string help = "Angle of the Halftoning" ,
    21.         float min = -180, float max = 180
    22.         ]],    
    23.     color  InputValue = 0.25
    24.         [[ string help = "The input value defining the size of the dots to yield the right halftone density. " ]],    
    25.     int  U_Input = 0
    26.         [[ string help = "If checked, adds the U coordinate as the input value. This works "
    27.                          "well when connected in a 'base_tonemap' input of an Arnold Toon shader.",
    28.            string widget = "checkBox" ]],        
    29.     float  Fuzz = 0.1 [[ float min = 0.0, float max = 2.0 ]],
    30.     color  BlackDots = 0.0
    31.         [[ string help = "The color of the dots" ]],        
    32.     color  WhiteDots = 1.0
    33.         [[ string help = "The color of the space between the dots" ]],        
    34.     // Outputs
    35.     output color Out = 0.0
    36. )
    37. {
    38.     vector pos = rotate(UVW, radians(Angle), 0.0, vector(0.0,0.0,1.0));
    39.     pos = vector(pos[0] / Scale[0], pos[1] / Scale[1], 0.0);
    40.     if (Scale[0] == 0.0)
    41.         pos[0] = 0.5;
    42.     if (Scale[1] == 0.0)
    43.         pos[1] = 0.5;
    45.     color inputV = InputValue;
    47.     if (U_Input)
    48.         inputV += u;    
    50.     pos = pos - floor(pos);
    52.     float dist = 1.0 - (distance(vector(0.5,0.5,0.0), pos) / (sqrt(2.0) / 2.5));    
    53.     color factor = smoothstep(-Fuzz, 0.0, inputV - sqrt(max(0,dist)));
    55.     Out = mix(BlackDots, WhiteDots, factor);
    56. }