MarchingCubes.hlsl

/*
 * Copyright 1993-2012 NVIDIA Corporation.  All rights reserved.
 *
 * Please refer to the NVIDIA end user license agreement (EULA) associated
 * with this source code for terms and conditions that govern your use of
 * this software. Any use, reproduction, disclosure, or distribution of
 * this software and related documentation outside the terms of the EULA
 * is strictly prohibited.
 *
 */

/*
   Tables for Marching Cubes
   http://local.wasp.uwa.edu.au/~pbourke/geometry/polygonise/
*/

// edge table maps 8-bit flag representing which cube vertices are inside
// the isosurface to 12-bit number indicating which edges are intersected
const static uint edgeTable[256] =
{
    0x0  , 0x109, 0x203, 0x30a, 0x406, 0x50f, 0x605, 0x70c,
    0x80c, 0x905, 0xa0f, 0xb06, 0xc0a, 0xd03, 0xe09, 0xf00,
    0x190, 0x99 , 0x393, 0x29a, 0x596, 0x49f, 0x795, 0x69c,
    0x99c, 0x895, 0xb9f, 0xa96, 0xd9a, 0xc93, 0xf99, 0xe90,
    0x230, 0x339, 0x33 , 0x13a, 0x636, 0x73f, 0x435, 0x53c,
    0xa3c, 0xb35, 0x83f, 0x936, 0xe3a, 0xf33, 0xc39, 0xd30,
    0x3a0, 0x2a9, 0x1a3, 0xaa , 0x7a6, 0x6af, 0x5a5, 0x4ac,
    0xbac, 0xaa5, 0x9af, 0x8a6, 0xfaa, 0xea3, 0xda9, 0xca0,
    0x460, 0x569, 0x663, 0x76a, 0x66 , 0x16f, 0x265, 0x36c,
    0xc6c, 0xd65, 0xe6f, 0xf66, 0x86a, 0x963, 0xa69, 0xb60,
    0x5f0, 0x4f9, 0x7f3, 0x6fa, 0x1f6, 0xff , 0x3f5, 0x2fc,
    0xdfc, 0xcf5, 0xfff, 0xef6, 0x9fa, 0x8f3, 0xbf9, 0xaf0,
    0x650, 0x759, 0x453, 0x55a, 0x256, 0x35f, 0x55 , 0x15c,
    0xe5c, 0xf55, 0xc5f, 0xd56, 0xa5a, 0xb53, 0x859, 0x950,
    0x7c0, 0x6c9, 0x5c3, 0x4ca, 0x3c6, 0x2cf, 0x1c5, 0xcc ,
    0xfcc, 0xec5, 0xdcf, 0xcc6, 0xbca, 0xac3, 0x9c9, 0x8c0,
    0x8c0, 0x9c9, 0xac3, 0xbca, 0xcc6, 0xdcf, 0xec5, 0xfcc,
    0xcc , 0x1c5, 0x2cf, 0x3c6, 0x4ca, 0x5c3, 0x6c9, 0x7c0,
    0x950, 0x859, 0xb53, 0xa5a, 0xd56, 0xc5f, 0xf55, 0xe5c,
    0x15c, 0x55 , 0x35f, 0x256, 0x55a, 0x453, 0x759, 0x650,
    0xaf0, 0xbf9, 0x8f3, 0x9fa, 0xef6, 0xfff, 0xcf5, 0xdfc,
    0x2fc, 0x3f5, 0xff , 0x1f6, 0x6fa, 0x7f3, 0x4f9, 0x5f0,
    0xb60, 0xa69, 0x963, 0x86a, 0xf66, 0xe6f, 0xd65, 0xc6c,
    0x36c, 0x265, 0x16f, 0x66 , 0x76a, 0x663, 0x569, 0x460,
    0xca0, 0xda9, 0xea3, 0xfaa, 0x8a6, 0x9af, 0xaa5, 0xbac,
    0x4ac, 0x5a5, 0x6af, 0x7a6, 0xaa , 0x1a3, 0x2a9, 0x3a0,
    0xd30, 0xc39, 0xf33, 0xe3a, 0x936, 0x83f, 0xb35, 0xa3c,
    0x53c, 0x435, 0x73f, 0x636, 0x13a, 0x33 , 0x339, 0x230,
    0xe90, 0xf99, 0xc93, 0xd9a, 0xa96, 0xb9f, 0x895, 0x99c,
    0x69c, 0x795, 0x49f, 0x596, 0x29a, 0x393, 0x99 , 0x190,
    0xf00, 0xe09, 0xd03, 0xc0a, 0xb06, 0xa0f, 0x905, 0x80c,
    0x70c, 0x605, 0x50f, 0x406, 0x30a, 0x203, 0x109, 0x0
};

// triangle table maps same cube vertex index to a list of up to 5 triangles
// which are built from the interpolated edge vertices
#define X 255
const static uint triTable[256][16] =
{
    {X, X, X, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {0, 8, 3, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {0, 1, 9, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {1, 8, 3, 9, 8, 1, X, X, X, X, X, X, X, X, X, X},
    {1, 2, 10, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {0, 8, 3, 1, 2, 10, X, X, X, X, X, X, X, X, X, X},
    {9, 2, 10, 0, 2, 9, X, X, X, X, X, X, X, X, X, X},
    {2, 8, 3, 2, 10, 8, 10, 9, 8, X, X, X, X, X, X, X},
    {3, 11, 2, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {0, 11, 2, 8, 11, 0, X, X, X, X, X, X, X, X, X, X},
    {1, 9, 0, 2, 3, 11, X, X, X, X, X, X, X, X, X, X},
    {1, 11, 2, 1, 9, 11, 9, 8, 11, X, X, X, X, X, X, X},
    {3, 10, 1, 11, 10, 3, X, X, X, X, X, X, X, X, X, X},
    {0, 10, 1, 0, 8, 10, 8, 11, 10, X, X, X, X, X, X, X},
    {3, 9, 0, 3, 11, 9, 11, 10, 9, X, X, X, X, X, X, X},
    {9, 8, 10, 10, 8, 11, X, X, X, X, X, X, X, X, X, X},
    {4, 7, 8, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {4, 3, 0, 7, 3, 4, X, X, X, X, X, X, X, X, X, X},
    {0, 1, 9, 8, 4, 7, X, X, X, X, X, X, X, X, X, X},
    {4, 1, 9, 4, 7, 1, 7, 3, 1, X, X, X, X, X, X, X},
    {1, 2, 10, 8, 4, 7, X, X, X, X, X, X, X, X, X, X},
    {3, 4, 7, 3, 0, 4, 1, 2, 10, X, X, X, X, X, X, X},
    {9, 2, 10, 9, 0, 2, 8, 4, 7, X, X, X, X, X, X, X},
    {2, 10, 9, 2, 9, 7, 2, 7, 3, 7, 9, 4, X, X, X, X},
    {8, 4, 7, 3, 11, 2, X, X, X, X, X, X, X, X, X, X},
    {11, 4, 7, 11, 2, 4, 2, 0, 4, X, X, X, X, X, X, X},
    {9, 0, 1, 8, 4, 7, 2, 3, 11, X, X, X, X, X, X, X},
    {4, 7, 11, 9, 4, 11, 9, 11, 2, 9, 2, 1, X, X, X, X},
    {3, 10, 1, 3, 11, 10, 7, 8, 4, X, X, X, X, X, X, X},
    {1, 11, 10, 1, 4, 11, 1, 0, 4, 7, 11, 4, X, X, X, X},
    {4, 7, 8, 9, 0, 11, 9, 11, 10, 11, 0, 3, X, X, X, X},
    {4, 7, 11, 4, 11, 9, 9, 11, 10, X, X, X, X, X, X, X},
    {9, 5, 4, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {9, 5, 4, 0, 8, 3, X, X, X, X, X, X, X, X, X, X},
    {0, 5, 4, 1, 5, 0, X, X, X, X, X, X, X, X, X, X},
    {8, 5, 4, 8, 3, 5, 3, 1, 5, X, X, X, X, X, X, X},
    {1, 2, 10, 9, 5, 4, X, X, X, X, X, X, X, X, X, X},
    {3, 0, 8, 1, 2, 10, 4, 9, 5, X, X, X, X, X, X, X},
    {5, 2, 10, 5, 4, 2, 4, 0, 2, X, X, X, X, X, X, X},
    {2, 10, 5, 3, 2, 5, 3, 5, 4, 3, 4, 8, X, X, X, X},
    {9, 5, 4, 2, 3, 11, X, X, X, X, X, X, X, X, X, X},
    {0, 11, 2, 0, 8, 11, 4, 9, 5, X, X, X, X, X, X, X},
    {0, 5, 4, 0, 1, 5, 2, 3, 11, X, X, X, X, X, X, X},
    {2, 1, 5, 2, 5, 8, 2, 8, 11, 4, 8, 5, X, X, X, X},
    {10, 3, 11, 10, 1, 3, 9, 5, 4, X, X, X, X, X, X, X},
    {4, 9, 5, 0, 8, 1, 8, 10, 1, 8, 11, 10, X, X, X, X},
    {5, 4, 0, 5, 0, 11, 5, 11, 10, 11, 0, 3, X, X, X, X},
    {5, 4, 8, 5, 8, 10, 10, 8, 11, X, X, X, X, X, X, X},
    {9, 7, 8, 5, 7, 9, X, X, X, X, X, X, X, X, X, X},
    {9, 3, 0, 9, 5, 3, 5, 7, 3, X, X, X, X, X, X, X},
    {0, 7, 8, 0, 1, 7, 1, 5, 7, X, X, X, X, X, X, X},
    {1, 5, 3, 3, 5, 7, X, X, X, X, X, X, X, X, X, X},
    {9, 7, 8, 9, 5, 7, 10, 1, 2, X, X, X, X, X, X, X},
    {10, 1, 2, 9, 5, 0, 5, 3, 0, 5, 7, 3, X, X, X, X},
    {8, 0, 2, 8, 2, 5, 8, 5, 7, 10, 5, 2, X, X, X, X},
    {2, 10, 5, 2, 5, 3, 3, 5, 7, X, X, X, X, X, X, X},
    {7, 9, 5, 7, 8, 9, 3, 11, 2, X, X, X, X, X, X, X},
    {9, 5, 7, 9, 7, 2, 9, 2, 0, 2, 7, 11, X, X, X, X},
    {2, 3, 11, 0, 1, 8, 1, 7, 8, 1, 5, 7, X, X, X, X},
    {11, 2, 1, 11, 1, 7, 7, 1, 5, X, X, X, X, X, X, X},
    {9, 5, 8, 8, 5, 7, 10, 1, 3, 10, 3, 11, X, X, X, X},
    {5, 7, 0, 5, 0, 9, 7, 11, 0, 1, 0, 10, 11, 10, 0, X},
    {11, 10, 0, 11, 0, 3, 10, 5, 0, 8, 0, 7, 5, 7, 0, X},
    {11, 10, 5, 7, 11, 5, X, X, X, X, X, X, X, X, X, X},
    {10, 6, 5, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {0, 8, 3, 5, 10, 6, X, X, X, X, X, X, X, X, X, X},
    {9, 0, 1, 5, 10, 6, X, X, X, X, X, X, X, X, X, X},
    {1, 8, 3, 1, 9, 8, 5, 10, 6, X, X, X, X, X, X, X},
    {1, 6, 5, 2, 6, 1, X, X, X, X, X, X, X, X, X, X},
    {1, 6, 5, 1, 2, 6, 3, 0, 8, X, X, X, X, X, X, X},
    {9, 6, 5, 9, 0, 6, 0, 2, 6, X, X, X, X, X, X, X},
    {5, 9, 8, 5, 8, 2, 5, 2, 6, 3, 2, 8, X, X, X, X},
    {2, 3, 11, 10, 6, 5, X, X, X, X, X, X, X, X, X, X},
    {11, 0, 8, 11, 2, 0, 10, 6, 5, X, X, X, X, X, X, X},
    {0, 1, 9, 2, 3, 11, 5, 10, 6, X, X, X, X, X, X, X},
    {5, 10, 6, 1, 9, 2, 9, 11, 2, 9, 8, 11, X, X, X, X},
    {6, 3, 11, 6, 5, 3, 5, 1, 3, X, X, X, X, X, X, X},
    {0, 8, 11, 0, 11, 5, 0, 5, 1, 5, 11, 6, X, X, X, X},
    {3, 11, 6, 0, 3, 6, 0, 6, 5, 0, 5, 9, X, X, X, X},
    {6, 5, 9, 6, 9, 11, 11, 9, 8, X, X, X, X, X, X, X},
    {5, 10, 6, 4, 7, 8, X, X, X, X, X, X, X, X, X, X},
    {4, 3, 0, 4, 7, 3, 6, 5, 10, X, X, X, X, X, X, X},
    {1, 9, 0, 5, 10, 6, 8, 4, 7, X, X, X, X, X, X, X},
    {10, 6, 5, 1, 9, 7, 1, 7, 3, 7, 9, 4, X, X, X, X},
    {6, 1, 2, 6, 5, 1, 4, 7, 8, X, X, X, X, X, X, X},
    {1, 2, 5, 5, 2, 6, 3, 0, 4, 3, 4, 7, X, X, X, X},
    {8, 4, 7, 9, 0, 5, 0, 6, 5, 0, 2, 6, X, X, X, X},
    {7, 3, 9, 7, 9, 4, 3, 2, 9, 5, 9, 6, 2, 6, 9, X},
    {3, 11, 2, 7, 8, 4, 10, 6, 5, X, X, X, X, X, X, X},
    {5, 10, 6, 4, 7, 2, 4, 2, 0, 2, 7, 11, X, X, X, X},
    {0, 1, 9, 4, 7, 8, 2, 3, 11, 5, 10, 6, X, X, X, X},
    {9, 2, 1, 9, 11, 2, 9, 4, 11, 7, 11, 4, 5, 10, 6, X},
    {8, 4, 7, 3, 11, 5, 3, 5, 1, 5, 11, 6, X, X, X, X},
    {5, 1, 11, 5, 11, 6, 1, 0, 11, 7, 11, 4, 0, 4, 11, X},
    {0, 5, 9, 0, 6, 5, 0, 3, 6, 11, 6, 3, 8, 4, 7, X},
    {6, 5, 9, 6, 9, 11, 4, 7, 9, 7, 11, 9, X, X, X, X},
    {10, 4, 9, 6, 4, 10, X, X, X, X, X, X, X, X, X, X},
    {4, 10, 6, 4, 9, 10, 0, 8, 3, X, X, X, X, X, X, X},
    {10, 0, 1, 10, 6, 0, 6, 4, 0, X, X, X, X, X, X, X},
    {8, 3, 1, 8, 1, 6, 8, 6, 4, 6, 1, 10, X, X, X, X},
    {1, 4, 9, 1, 2, 4, 2, 6, 4, X, X, X, X, X, X, X},
    {3, 0, 8, 1, 2, 9, 2, 4, 9, 2, 6, 4, X, X, X, X},
    {0, 2, 4, 4, 2, 6, X, X, X, X, X, X, X, X, X, X},
    {8, 3, 2, 8, 2, 4, 4, 2, 6, X, X, X, X, X, X, X},
    {10, 4, 9, 10, 6, 4, 11, 2, 3, X, X, X, X, X, X, X},
    {0, 8, 2, 2, 8, 11, 4, 9, 10, 4, 10, 6, X, X, X, X},
    {3, 11, 2, 0, 1, 6, 0, 6, 4, 6, 1, 10, X, X, X, X},
    {6, 4, 1, 6, 1, 10, 4, 8, 1, 2, 1, 11, 8, 11, 1, X},
    {9, 6, 4, 9, 3, 6, 9, 1, 3, 11, 6, 3, X, X, X, X},
    {8, 11, 1, 8, 1, 0, 11, 6, 1, 9, 1, 4, 6, 4, 1, X},
    {3, 11, 6, 3, 6, 0, 0, 6, 4, X, X, X, X, X, X, X},
    {6, 4, 8, 11, 6, 8, X, X, X, X, X, X, X, X, X, X},
    {7, 10, 6, 7, 8, 10, 8, 9, 10, X, X, X, X, X, X, X},
    {0, 7, 3, 0, 10, 7, 0, 9, 10, 6, 7, 10, X, X, X, X},
    {10, 6, 7, 1, 10, 7, 1, 7, 8, 1, 8, 0, X, X, X, X},
    {10, 6, 7, 10, 7, 1, 1, 7, 3, X, X, X, X, X, X, X},
    {1, 2, 6, 1, 6, 8, 1, 8, 9, 8, 6, 7, X, X, X, X},
    {2, 6, 9, 2, 9, 1, 6, 7, 9, 0, 9, 3, 7, 3, 9, X},
    {7, 8, 0, 7, 0, 6, 6, 0, 2, X, X, X, X, X, X, X},
    {7, 3, 2, 6, 7, 2, X, X, X, X, X, X, X, X, X, X},
    {2, 3, 11, 10, 6, 8, 10, 8, 9, 8, 6, 7, X, X, X, X},
    {2, 0, 7, 2, 7, 11, 0, 9, 7, 6, 7, 10, 9, 10, 7, X},
    {1, 8, 0, 1, 7, 8, 1, 10, 7, 6, 7, 10, 2, 3, 11, X},
    {11, 2, 1, 11, 1, 7, 10, 6, 1, 6, 7, 1, X, X, X, X},
    {8, 9, 6, 8, 6, 7, 9, 1, 6, 11, 6, 3, 1, 3, 6, X},
    {0, 9, 1, 11, 6, 7, X, X, X, X, X, X, X, X, X, X},
    {7, 8, 0, 7, 0, 6, 3, 11, 0, 11, 6, 0, X, X, X, X},
    {7, 11, 6, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {7, 6, 11, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {3, 0, 8, 11, 7, 6, X, X, X, X, X, X, X, X, X, X},
    {0, 1, 9, 11, 7, 6, X, X, X, X, X, X, X, X, X, X},
    {8, 1, 9, 8, 3, 1, 11, 7, 6, X, X, X, X, X, X, X},
    {10, 1, 2, 6, 11, 7, X, X, X, X, X, X, X, X, X, X},
    {1, 2, 10, 3, 0, 8, 6, 11, 7, X, X, X, X, X, X, X},
    {2, 9, 0, 2, 10, 9, 6, 11, 7, X, X, X, X, X, X, X},
    {6, 11, 7, 2, 10, 3, 10, 8, 3, 10, 9, 8, X, X, X, X},
    {7, 2, 3, 6, 2, 7, X, X, X, X, X, X, X, X, X, X},
    {7, 0, 8, 7, 6, 0, 6, 2, 0, X, X, X, X, X, X, X},
    {2, 7, 6, 2, 3, 7, 0, 1, 9, X, X, X, X, X, X, X},
    {1, 6, 2, 1, 8, 6, 1, 9, 8, 8, 7, 6, X, X, X, X},
    {10, 7, 6, 10, 1, 7, 1, 3, 7, X, X, X, X, X, X, X},
    {10, 7, 6, 1, 7, 10, 1, 8, 7, 1, 0, 8, X, X, X, X},
    {0, 3, 7, 0, 7, 10, 0, 10, 9, 6, 10, 7, X, X, X, X},
    {7, 6, 10, 7, 10, 8, 8, 10, 9, X, X, X, X, X, X, X},
    {6, 8, 4, 11, 8, 6, X, X, X, X, X, X, X, X, X, X},
    {3, 6, 11, 3, 0, 6, 0, 4, 6, X, X, X, X, X, X, X},
    {8, 6, 11, 8, 4, 6, 9, 0, 1, X, X, X, X, X, X, X},
    {9, 4, 6, 9, 6, 3, 9, 3, 1, 11, 3, 6, X, X, X, X},
    {6, 8, 4, 6, 11, 8, 2, 10, 1, X, X, X, X, X, X, X},
    {1, 2, 10, 3, 0, 11, 0, 6, 11, 0, 4, 6, X, X, X, X},
    {4, 11, 8, 4, 6, 11, 0, 2, 9, 2, 10, 9, X, X, X, X},
    {10, 9, 3, 10, 3, 2, 9, 4, 3, 11, 3, 6, 4, 6, 3, X},
    {8, 2, 3, 8, 4, 2, 4, 6, 2, X, X, X, X, X, X, X},
    {0, 4, 2, 4, 6, 2, X, X, X, X, X, X, X, X, X, X},
    {1, 9, 0, 2, 3, 4, 2, 4, 6, 4, 3, 8, X, X, X, X},
    {1, 9, 4, 1, 4, 2, 2, 4, 6, X, X, X, X, X, X, X},
    {8, 1, 3, 8, 6, 1, 8, 4, 6, 6, 10, 1, X, X, X, X},
    {10, 1, 0, 10, 0, 6, 6, 0, 4, X, X, X, X, X, X, X},
    {4, 6, 3, 4, 3, 8, 6, 10, 3, 0, 3, 9, 10, 9, 3, X},
    {10, 9, 4, 6, 10, 4, X, X, X, X, X, X, X, X, X, X},
    {4, 9, 5, 7, 6, 11, X, X, X, X, X, X, X, X, X, X},
    {0, 8, 3, 4, 9, 5, 11, 7, 6, X, X, X, X, X, X, X},
    {5, 0, 1, 5, 4, 0, 7, 6, 11, X, X, X, X, X, X, X},
    {11, 7, 6, 8, 3, 4, 3, 5, 4, 3, 1, 5, X, X, X, X},
    {9, 5, 4, 10, 1, 2, 7, 6, 11, X, X, X, X, X, X, X},
    {6, 11, 7, 1, 2, 10, 0, 8, 3, 4, 9, 5, X, X, X, X},
    {7, 6, 11, 5, 4, 10, 4, 2, 10, 4, 0, 2, X, X, X, X},
    {3, 4, 8, 3, 5, 4, 3, 2, 5, 10, 5, 2, 11, 7, 6, X},
    {7, 2, 3, 7, 6, 2, 5, 4, 9, X, X, X, X, X, X, X},
    {9, 5, 4, 0, 8, 6, 0, 6, 2, 6, 8, 7, X, X, X, X},
    {3, 6, 2, 3, 7, 6, 1, 5, 0, 5, 4, 0, X, X, X, X},
    {6, 2, 8, 6, 8, 7, 2, 1, 8, 4, 8, 5, 1, 5, 8, X},
    {9, 5, 4, 10, 1, 6, 1, 7, 6, 1, 3, 7, X, X, X, X},
    {1, 6, 10, 1, 7, 6, 1, 0, 7, 8, 7, 0, 9, 5, 4, X},
    {4, 0, 10, 4, 10, 5, 0, 3, 10, 6, 10, 7, 3, 7, 10, X},
    {7, 6, 10, 7, 10, 8, 5, 4, 10, 4, 8, 10, X, X, X, X},
    {6, 9, 5, 6, 11, 9, 11, 8, 9, X, X, X, X, X, X, X},
    {3, 6, 11, 0, 6, 3, 0, 5, 6, 0, 9, 5, X, X, X, X},
    {0, 11, 8, 0, 5, 11, 0, 1, 5, 5, 6, 11, X, X, X, X},
    {6, 11, 3, 6, 3, 5, 5, 3, 1, X, X, X, X, X, X, X},
    {1, 2, 10, 9, 5, 11, 9, 11, 8, 11, 5, 6, X, X, X, X},
    {0, 11, 3, 0, 6, 11, 0, 9, 6, 5, 6, 9, 1, 2, 10, X},
    {11, 8, 5, 11, 5, 6, 8, 0, 5, 10, 5, 2, 0, 2, 5, X},
    {6, 11, 3, 6, 3, 5, 2, 10, 3, 10, 5, 3, X, X, X, X},
    {5, 8, 9, 5, 2, 8, 5, 6, 2, 3, 8, 2, X, X, X, X},
    {9, 5, 6, 9, 6, 0, 0, 6, 2, X, X, X, X, X, X, X},
    {1, 5, 8, 1, 8, 0, 5, 6, 8, 3, 8, 2, 6, 2, 8, X},
    {1, 5, 6, 2, 1, 6, X, X, X, X, X, X, X, X, X, X},
    {1, 3, 6, 1, 6, 10, 3, 8, 6, 5, 6, 9, 8, 9, 6, X},
    {10, 1, 0, 10, 0, 6, 9, 5, 0, 5, 6, 0, X, X, X, X},
    {0, 3, 8, 5, 6, 10, X, X, X, X, X, X, X, X, X, X},
    {10, 5, 6, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {11, 5, 10, 7, 5, 11, X, X, X, X, X, X, X, X, X, X},
    {11, 5, 10, 11, 7, 5, 8, 3, 0, X, X, X, X, X, X, X},
    {5, 11, 7, 5, 10, 11, 1, 9, 0, X, X, X, X, X, X, X},
    {10, 7, 5, 10, 11, 7, 9, 8, 1, 8, 3, 1, X, X, X, X},
    {11, 1, 2, 11, 7, 1, 7, 5, 1, X, X, X, X, X, X, X},
    {0, 8, 3, 1, 2, 7, 1, 7, 5, 7, 2, 11, X, X, X, X},
    {9, 7, 5, 9, 2, 7, 9, 0, 2, 2, 11, 7, X, X, X, X},
    {7, 5, 2, 7, 2, 11, 5, 9, 2, 3, 2, 8, 9, 8, 2, X},
    {2, 5, 10, 2, 3, 5, 3, 7, 5, X, X, X, X, X, X, X},
    {8, 2, 0, 8, 5, 2, 8, 7, 5, 10, 2, 5, X, X, X, X},
    {9, 0, 1, 5, 10, 3, 5, 3, 7, 3, 10, 2, X, X, X, X},
    {9, 8, 2, 9, 2, 1, 8, 7, 2, 10, 2, 5, 7, 5, 2, X},
    {1, 3, 5, 3, 7, 5, X, X, X, X, X, X, X, X, X, X},
    {0, 8, 7, 0, 7, 1, 1, 7, 5, X, X, X, X, X, X, X},
    {9, 0, 3, 9, 3, 5, 5, 3, 7, X, X, X, X, X, X, X},
    {9, 8, 7, 5, 9, 7, X, X, X, X, X, X, X, X, X, X},
    {5, 8, 4, 5, 10, 8, 10, 11, 8, X, X, X, X, X, X, X},
    {5, 0, 4, 5, 11, 0, 5, 10, 11, 11, 3, 0, X, X, X, X},
    {0, 1, 9, 8, 4, 10, 8, 10, 11, 10, 4, 5, X, X, X, X},
    {10, 11, 4, 10, 4, 5, 11, 3, 4, 9, 4, 1, 3, 1, 4, X},
    {2, 5, 1, 2, 8, 5, 2, 11, 8, 4, 5, 8, X, X, X, X},
    {0, 4, 11, 0, 11, 3, 4, 5, 11, 2, 11, 1, 5, 1, 11, X},
    {0, 2, 5, 0, 5, 9, 2, 11, 5, 4, 5, 8, 11, 8, 5, X},
    {9, 4, 5, 2, 11, 3, X, X, X, X, X, X, X, X, X, X},
    {2, 5, 10, 3, 5, 2, 3, 4, 5, 3, 8, 4, X, X, X, X},
    {5, 10, 2, 5, 2, 4, 4, 2, 0, X, X, X, X, X, X, X},
    {3, 10, 2, 3, 5, 10, 3, 8, 5, 4, 5, 8, 0, 1, 9, X},
    {5, 10, 2, 5, 2, 4, 1, 9, 2, 9, 4, 2, X, X, X, X},
    {8, 4, 5, 8, 5, 3, 3, 5, 1, X, X, X, X, X, X, X},
    {0, 4, 5, 1, 0, 5, X, X, X, X, X, X, X, X, X, X},
    {8, 4, 5, 8, 5, 3, 9, 0, 5, 0, 3, 5, X, X, X, X},
    {9, 4, 5, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {4, 11, 7, 4, 9, 11, 9, 10, 11, X, X, X, X, X, X, X},
    {0, 8, 3, 4, 9, 7, 9, 11, 7, 9, 10, 11, X, X, X, X},
    {1, 10, 11, 1, 11, 4, 1, 4, 0, 7, 4, 11, X, X, X, X},
    {3, 1, 4, 3, 4, 8, 1, 10, 4, 7, 4, 11, 10, 11, 4, X},
    {4, 11, 7, 9, 11, 4, 9, 2, 11, 9, 1, 2, X, X, X, X},
    {9, 7, 4, 9, 11, 7, 9, 1, 11, 2, 11, 1, 0, 8, 3, X},
    {11, 7, 4, 11, 4, 2, 2, 4, 0, X, X, X, X, X, X, X},
    {11, 7, 4, 11, 4, 2, 8, 3, 4, 3, 2, 4, X, X, X, X},
    {2, 9, 10, 2, 7, 9, 2, 3, 7, 7, 4, 9, X, X, X, X},
    {9, 10, 7, 9, 7, 4, 10, 2, 7, 8, 7, 0, 2, 0, 7, X},
    {3, 7, 10, 3, 10, 2, 7, 4, 10, 1, 10, 0, 4, 0, 10, X},
    {1, 10, 2, 8, 7, 4, X, X, X, X, X, X, X, X, X, X},
    {4, 9, 1, 4, 1, 7, 7, 1, 3, X, X, X, X, X, X, X},
    {4, 9, 1, 4, 1, 7, 0, 8, 1, 8, 7, 1, X, X, X, X},
    {4, 0, 3, 7, 4, 3, X, X, X, X, X, X, X, X, X, X},
    {4, 8, 7, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {9, 10, 8, 10, 11, 8, X, X, X, X, X, X, X, X, X, X},
    {3, 0, 9, 3, 9, 11, 11, 9, 10, X, X, X, X, X, X, X},
    {0, 1, 10, 0, 10, 8, 8, 10, 11, X, X, X, X, X, X, X},
    {3, 1, 10, 11, 3, 10, X, X, X, X, X, X, X, X, X, X},
    {1, 2, 11, 1, 11, 9, 9, 11, 8, X, X, X, X, X, X, X},
    {3, 0, 9, 3, 9, 11, 1, 2, 9, 2, 11, 9, X, X, X, X},
    {0, 2, 11, 8, 0, 11, X, X, X, X, X, X, X, X, X, X},
    {3, 2, 11, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {2, 3, 8, 2, 8, 10, 10, 8, 9, X, X, X, X, X, X, X},
    {9, 10, 2, 0, 9, 2, X, X, X, X, X, X, X, X, X, X},
    {2, 3, 8, 2, 8, 10, 0, 1, 8, 1, 10, 8, X, X, X, X},
    {1, 10, 2, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {1, 3, 8, 9, 1, 8, X, X, X, X, X, X, X, X, X, X},
    {0, 9, 1, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {0, 3, 8, X, X, X, X, X, X, X, X, X, X, X, X, X},
    {X, X, X, X, X, X, X, X, X, X, X, X, X, X, X, X}
};
#undef X

// number of vertices for each case above
const static uint numVertsTable[256] =
{
    0,
    3,
    3,
    6,
    3,
    6,
    6,
    9,
    3,
    6,
    6,
    9,
    6,
    9,
    9,
    6,
    3,
    6,
    6,
    9,
    6,
    9,
    9,
    12,
    6,
    9,
    9,
    12,
    9,
    12,
    12,
    9,
    3,
    6,
    6,
    9,
    6,
    9,
    9,
    12,
    6,
    9,
    9,
    12,
    9,
    12,
    12,
    9,
    6,
    9,
    9,
    6,
    9,
    12,
    12,
    9,
    9,
    12,
    12,
    9,
    12,
    15,
    15,
    6,
    3,
    6,
    6,
    9,
    6,
    9,
    9,
    12,
    6,
    9,
    9,
    12,
    9,
    12,
    12,
    9,
    6,
    9,
    9,
    12,
    9,
    12,
    12,
    15,
    9,
    12,
    12,
    15,
    12,
    15,
    15,
    12,
    6,
    9,
    9,
    12,
    9,
    12,
    6,
    9,
    9,
    12,
    12,
    15,
    12,
    15,
    9,
    6,
    9,
    12,
    12,
    9,
    12,
    15,
    9,
    6,
    12,
    15,
    15,
    12,
    15,
    6,
    12,
    3,
    3,
    6,
    6,
    9,
    6,
    9,
    9,
    12,
    6,
    9,
    9,
    12,
    9,
    12,
    12,
    9,
    6,
    9,
    9,
    12,
    9,
    12,
    12,
    15,
    9,
    6,
    12,
    9,
    12,
    9,
    15,
    6,
    6,
    9,
    9,
    12,
    9,
    12,
    12,
    15,
    9,
    12,
    12,
    15,
    12,
    15,
    15,
    12,
    9,
    12,
    12,
    9,
    12,
    15,
    15,
    12,
    12,
    9,
    15,
    6,
    15,
    12,
    6,
    3,
    6,
    9,
    9,
    12,
    9,
    12,
    12,
    15,
    9,
    12,
    12,
    15,
    6,
    9,
    9,
    6,
    9,
    12,
    12,
    15,
    12,
    15,
    15,
    6,
    12,
    9,
    15,
    12,
    9,
    6,
    12,
    3,
    9,
    12,
    12,
    15,
    12,
    15,
    9,
    12,
    12,
    15,
    15,
    6,
    9,
    12,
    6,
    3,
    6,
    9,
    9,
    6,
    9,
    12,
    6,
    3,
    9,
    6,
    12,
    3,
    6,
    3,
    3,
    0,
};

const static uint3 cellPos[] = 
{
	{0, 0, 0}, //0
	{1, 0, 0}, //1
	{1, 1, 0}, //2
	{0, 1, 0}, //3
	{0, 0, 1}, //4
	{1, 0, 1}, //5
	{1, 1, 1}, //6
	{0, 1, 1}  //7
};

const static float3 cellPos2[] = 
{
	{0, 0, 0}, //0
	{1, 0, 0}, //1
	{1, 1, 0}, //2
	{0, 1, 0}, //3
	{0, 0, 1}, //4
	{1, 0, 1}, //5
	{1, 1, 1}, //6
	{0, 1, 1}  //7
};

const static uint3 subPos[] = {
	{1, 3, 4},
	{0, 2, 5},
	{3, 1, 6},
	{2, 0, 7},
	{5, 7, 0},
	{4, 6, 1},
	{7, 5, 2},
	{6, 4, 3}
};

const static float3 normInv[] = {
	{1, 1, 1},
	{-1, 1, 1},
	{-1, -1, 1},
	{1, -1, 1},
	{1, 1, -1},
	{-1, 1, -1},
	{-1, -1, -1},
	{1, -1, -1}
};

const static uint2 idxTable[] = 
{
	{0, 1},
	{1, 2},
	{2, 3},
	{3, 0},
	{4, 5},
	{5, 6},
	{6, 7},
	{7, 4},
	{0, 4},
	{1, 5},
	{2, 6},
	{3, 7}
};

#define SIMULATION_BLOCK_SIZE 128

struct Vertex
{
	float3 vPosition;
	float3 vNormal;
};

struct Triangle
{
	Vertex v[3];
};

Texture3D<float> texDensityField	:	register( t0 );
AppendStructuredBuffer<Triangle> VerticesRW : register( u0 );
RWBuffer<uint> NumVertsRW : register(u0); 
StructuredBuffer<uint> ParticlesAnisoRO : register( t9 );
Buffer<uint> NumCellsRO : register( t11 );

SamplerState g_sampLinear : register( s0 );

cbuffer cbMarchingCubesConstants : register( b1 )
{
	uint4 gridSize;
	uint4 gridSizeShift;
	uint4 gridSizeMask;
	float4 voxelSize;
};


cbuffer cbGridDimConstants : register( b4 ) 
{
	int4 g_iGridMin;
	int4 g_iGridDim;
	int4 g_iGridDot;
};

cbuffer cbRenderConstants : register( b0 )
{
	matrix g_mViewProjection[2];
	matrix g_mView;
	float4 g_fVolSlicing;
	float4 g_fTessFactor;
	float4 g_fEyePos;
	float4 g_fRMAssist;
	float4 g_fRMAssist2;
	float g_fSmoothlen;
	float g_fParticleSize;
	float g_fParticleAspectRatio;
	float g_fInvGridSize;
};

uint3 calcGridPos(uint i)
{
	uint3 gridPos;
	gridPos.x = i & gridSizeMask.x;
	gridPos.y = (i >> gridSizeShift.y) & gridSizeMask.y;
	gridPos.z = (i >> gridSizeShift.z) & gridSizeMask.z;
	return gridPos;
}

float tangle(float x, float y, float z)
{
	x *= 3.0f;
	y *= 3.0f;
	z *= 3.0f;
	return (x*x*x*x - 5.0f*x*x +y*y*y*y - 5.0f*y*y +z*z*z*z - 5.0f*z*z + 11.8f) * 0.2f + 0.5f;
}

float fieldFunc(float3 p)
{
//	return tangle(p.x, p.y, p.z);
	float3 tex = p * g_fRMAssist.xyz + g_fRMAssist2.xyz;
	return texDensityField.SampleLevel(g_sampLinear, tex.xzy, 0);
}

float3 vertexInterp(float isolevel, float3 p0, float3 p1, float f0, float f1)
{
	float t = (isolevel - f0) / (f1 - f0);
	return lerp(p0, p1, t);
}

float3 calcNormal(float3 v0, float3 v1, float3 v2)
{
	float3 edge0 = v1 - v0;
	float3 edge1 = v2 - v0;
	// note - it's faster to perform normalization in vertex shader rather than here
	return cross(edge0, edge1);
}

uint3 GridDecomposeKeyMC(uint key)
{
	// Bit pack [----Y---][----Z---][----X---]
	//              8-bit		8-bit		8-bit
	uint2 gridDim = g_iGridDim.xz * 3 + 3;
	uint y = key / (gridDim.x * gridDim.y);
	uint xz = key - y * (gridDim.x * gridDim.y);
	uint z = xz / gridDim.x;
	uint x = xz - z * gridDim.x;

    return uint3(x, y, z);
}

groupshared float3 vertlist[12 * SIMULATION_BLOCK_SIZE];

[numthreads(SIMULATION_BLOCK_SIZE, 1, 1)]
void MarchingCubesCS( 
	uint3 Gid : SV_GroupID, 
	uint3 DTid : SV_DispatchThreadID, 
	uint3 GTid : SV_GroupThreadID, 
	uint GI : SV_GroupIndex )
{
	int i = DTid.x;

	if(i >= g_iGridDot.z)
		return;

	uint3 gridPos = GridDecomposeKeyMC(i);

	float3 p = (((float3) gridPos * 0.33333333f + g_iGridMin.xyz) - 0.66666667f) * g_fSmoothlen;

	float3 v[8];
	float field[8];
	uint cubeindex = 0;

	for(uint j = 0; j < 8; j++) {
		v[j] = p + cellPos2[j] * g_fSmoothlen * 0.33333333f;
		field[j] = texDensityField[(gridPos + cellPos[j]).xzy];
		cubeindex |= ((uint)(field[j] < voxelSize.w) << j);
	} 

	uint numVerts = numVertsTable[cubeindex];

	if(numVerts != 0) 
	{
		for(uint j = 0; j < 12; j++) {
			uint2 idx = idxTable[j];
			vertlist[GTid.x + (SIMULATION_BLOCK_SIZE * j)] =
				vertexInterp(voxelSize.w, 
				v[idx.x], v[idx.y], 
				field[idx.x], field[idx.y]);
		}

		for(uint l = 0; l < 15; l += 3) {	
			if(l < numVerts) {
				float3 norm[3];
				for(uint k = 0; k < 3; k++) {
					uint edge = triTable[cubeindex][l + k];
					v[k] = vertlist[(edge * SIMULATION_BLOCK_SIZE) + GTid.x];


					norm[k] = normalize(float3(
						fieldFunc(  v[k] - float3(0.33333333f, 0, 0) * g_fSmoothlen) 
						- fieldFunc(v[k] + float3(0.33333333f, 0, 0) * g_fSmoothlen),
						fieldFunc(  v[k] - float3(0, 0.33333333f, 0) * g_fSmoothlen) 
						- fieldFunc(v[k] + float3(0, 0.33333333f, 0) * g_fSmoothlen),
						fieldFunc(  v[k] - float3(0, 0, 0.33333333f) * g_fSmoothlen) 
						- fieldFunc(v[k] + float3(0, 0, 0.33333333f) * g_fSmoothlen)
						));
				}

				Triangle t;

				t.v[0].vPosition = v[0];
				t.v[0].vNormal =   norm[0];
				t.v[1].vPosition = v[2];
				t.v[1].vNormal =   norm[2];
				t.v[2].vPosition = v[1];
				t.v[2].vNormal =   norm[1];

				VerticesRW.Append(t);
			}
		}
	}
}

[numthreads(1, 1, 1)]
void AdjustNumVertsCS()
{
	NumVertsRW[0] *= 3;
	NumVertsRW[1] = 1;
	NumVertsRW[2] = 0;
	NumVertsRW[3] = 0;
}