/////////////////////////////////////////////////////////////////////////////
// metal.osl -- metal surface with optional reflections
//
// Parameters:
//    Ka, Kd, Ks, roughness - The usual meaning
//    Kr - coefficient for mirror-like reflections of environment
//    blur - how blurry are the reflections? (0 = perfectly sharp)
//    envname - name of environment map, or geometry set for ray tracing
//              (setting to "" means no mirror reflections)
//    envspace - coord sys for env map lookups (ignored
//          for ray tracing)
//    samples - how many samples, for ray tracing blurry reflections
//    twosided - if nonzero both sides of the surface are shiny, otherwise
//        only the "outside" (where the surface normal points) will
//        have reflections.  This can be an important optimization,
//        especially when ray tracing.
//
/////////////////////////////////////////////////////////////////////////////
// Copyright 2004 NVIDIA Corporation.  All Rights Reserved.
// 
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
// 
// * Redistributions of source code must retain the above copyright
//   notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the
//   documentation and/or other materials provided with the distribution.
// * Neither the name of NVIDIA nor the names of its contributors
//   may be used to endorse or promote products derived from this software
//   without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// (This is the Modified BSD License)
/////////////////////////////////////////////////////////////////////////////

#include "material.h"

surface
metal 
    [[ string help = "Metal, simple, with reflections" ]]
( 
    float Ka = 1
        [[  string help = "Ambient scaling",
            float min = 0, float max = 1 ]],
    float Kd = 0.1
        [[  string help = "Diffuse scaling",
            float min = 0, float max = 1 ]],
    float Ks = 0.8
        [[  string help = "Specular scaling",
            float min = 0, float max = 1 ]],
    float roughness = 0.2
        [[  string help = "Surface roughness (specular highlight size)",
            float min = 0, float max = 1 ]],

    float Kr = 0.5
        [[  string help = "Reflectivity / Environment scaling",
            float min = 0, float max = 1 ]],
    string envname = ""
        [[  string help = "Map or geometry set name for reflections" ]],
    float blur = 0
        [[  string help = "Environment blur",
            float min = 0, float max = 1 ]],
    string envspace = "world"
        [[  string help = "Coordinate system for environment map lookup" ]],
    float samples = 1
        [[  string help = "Environment samples (for ray tracing)",
            float min = 1, float max = 64 ]],
    float twosided = 0
        [[  string help = "Two-sided reflections" ]]
  )
{
    normal Nf = faceforward (normalize(N), I);
    C = MaterialShinyMetal (Nf, C, Ka, Kd, Ks, roughness, Kr, blur,
                              twosided, envname, envspace, samples);

    // Scale color by opacity.
    C *= opacity;
}
