--- /dev/null
+## Copyright (C) 2009-2012 Martin Helm
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or (at
+## your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+## General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING. If not, see
+## <http://www.gnu.org/licenses/>.
+##
+## Author: Martin Helm <martin@mhelm.de>
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {[@var{vxyz}, @var{idx}, @var{frac}] =} __interp_cube__ (@var{x}, @var{y}, @var{z}, @var{val}, @var{v})
+## Undocumented internal function.
+## @end deftypefn
+
+function [Vxyz, idx, frac] = __interp_cube__(x, y, z, val, v, req = "values" )
+ if (ismatrix (x) && ndims (x) == 3 && ismatrix (y) && ndims (y) == 3 ...
+ && ismatrix (z) && ndims (z) == 3 && size_equal (x, y, z, val))
+ x = squeeze (x(1,:,1))(:);
+ y = squeeze (y(:,1,1))(:);
+ z = squeeze (z(1,1,:))(:);
+ elseif (isvector (x) && isvector (y) && isvector (z) )
+ x = x(:);
+ y = y(:);
+ z = z(:);
+ else
+ error("__interp_cube__: X, Y, Z have wrong dimensions");
+ endif
+ if (size (val) != [length(x), length(y), length(z)])
+ error ("__interp_cube__: VAL has wrong dimensions");
+ endif
+ if (size (v, 2) != 3)
+ error ( "v has to be N*3 matrix");
+ endif
+ if (!ischar (req))
+ error ("__interp_cube__: Invalid request parameter use 'values', 'normals' or 'normals8'");
+ endif
+ if (isempty (v))
+ Vxyz = idx = frac = [];
+ return
+ endif
+
+ switch (req)
+ case "values"
+ [Vxyz, idx, frac] = interp_cube_trilin (x, y, z, val, v);
+ case "normals"
+ [idx, frac] = cube_idx (x, y, z, v);
+
+ dx = x(2:end) - x(1:end-1);
+ dy = y(2:end) - y(1:end-1);
+ dz = z(2:end) - z(1:end-1);
+ dx = 0.5 .* [dx;dx(end)](idx(:,2));
+ dy = 0.5 .* [dy;dy(end)](idx(:,1));
+ dz = 0.5 .* [dz;dz(end)](idx(:,3));
+
+ p000 = [v(:, 1) - dx, v(:, 2) - dy, v(:, 3) - dz];
+ p100 = [v(:, 1) + dx, v(:, 2) - dy, v(:, 3) - dz];
+ p010 = [v(:, 1) - dx, v(:, 2) + dy, v(:, 3) - dz];
+ p001 = [v(:, 1) - dx, v(:, 2) - dy, v(:, 3) + dz];
+ p011 = [v(:, 1) - dx, v(:, 2) + dy, v(:, 3) + dz];
+ p101 = [v(:, 1) + dx, v(:, 2) - dy, v(:, 3) + dz];
+ p110 = [v(:, 1) + dx, v(:, 2) + dy, v(:, 3) - dz];
+ p111 = [v(:, 1) + dx, v(:, 2) + dy, v(:, 3) + dz];
+
+ v000 = interp_cube_trilin (x, y, z, val, p000);
+ v100 = interp_cube_trilin (x, y, z, val, p100);
+ v010 = interp_cube_trilin (x, y, z, val, p010);
+ v001 = interp_cube_trilin (x, y, z, val, p001);
+ v011 = interp_cube_trilin (x, y, z, val, p011);
+ v101 = interp_cube_trilin (x, y, z, val, p101);
+ v110 = interp_cube_trilin (x, y, z, val, p110);
+ v111 = interp_cube_trilin (x, y, z, val, p111);
+
+ Dx = -v000 .+ v100 .- v010 .- v001 .- v011 .+ v101 .+ v110 .+ v111;
+ Dy = -v000 .- v100 .+ v010 .- v001 .+ v011 .- v101 .+ v110 .+ v111;
+ Dz = -v000 .- v100 .- v010 .+ v001 .+ v011 .+ v101 .- v110 .+ v111;
+ Vxyz = 0.5 .* [Dx./dx, Dy./dy, Dz./dz];
+ case "normals8"
+ [idx, frac] = cube_idx (x, y, z, v);
+
+ dx = x(2:end) - x(1:end-1);
+ dy = y(2:end) - y(1:end-1);
+ dz = z(2:end) - z(1:end-1);
+ dx = [dx;dx(end)](idx(:,2));
+ dy = [dy;dy(end)](idx(:,1));
+ dz = [dz;dz(end)](idx(:,3));
+ [Dx, Dy, Dz, idx, frac] = interp_cube_trilin_grad (x, y, z, val, v);
+ Vxyz = [Dx./dx, Dy./dy, Dz./dz];
+ otherwise
+ error ("__interp_cube__: Invalid request type '%s', use 'values', 'normals' or 'normals8'", req);
+ endswitch
+endfunction
+
+function [Vxyz, idx, frac] = interp_cube_trilin(x, y, z, val, v)
+ [idx, frac] = cube_idx (x(:), y(:), z(:), v);
+ sval = size (val);
+ i000 = sub2ind (sval, idx(:, 1), idx(:, 2), idx(:, 3));
+ i100 = sub2ind (sval, idx(:, 1)+1, idx(:, 2), idx(:, 3));
+ i010 = sub2ind (sval, idx(:, 1), idx(:, 2)+1, idx(:, 3));
+ i001 = sub2ind (sval, idx(:, 1), idx(:, 2), idx(:, 3)+1);
+ i101 = sub2ind (sval, idx(:, 1)+1, idx(:, 2), idx(:, 3)+1);
+ i011 = sub2ind (sval, idx(:, 1), idx(:, 2)+1, idx(:, 3)+1);
+ i110 = sub2ind (sval, idx(:, 1)+1, idx(:, 2)+1, idx(:, 3));
+ i111 = sub2ind (sval, idx(:, 1)+1, idx(:, 2)+1, idx(:, 3)+1 );
+ Bx = frac(:, 1);
+ By = frac(:, 2);
+ Bz = frac(:, 3);
+ Vxyz = ...
+ val( i000 ) .* (1 .- Bx) .* (1 .- By) .* (1 .- Bz) .+ ...
+ val( i100 ) .* Bx .* (1 .- By) .* (1 .- Bz) .+ ...
+ val( i010 ) .* (1 .- Bx) .* By .* (1 .- Bz) .+ ...
+ val( i001 ) .* (1 .- Bx) .* (1 .- By) .* Bz .+ ...
+ val( i011 ) .* (1 .- Bx) .* By .* Bz .+ ...
+ val( i101 ) .* Bx .* (1 .- By) .* Bz .+ ...
+ val( i110 ) .* Bx .* By .* (1 .- Bz) .+ ...
+ val( i111 ) .* Bx .* By .* Bz;
+endfunction
+
+function [Dx, Dy, Dz, idx, frac] = interp_cube_trilin_grad(x, y, z, val, v)
+ [idx, frac] = cube_idx (x(:), y(:), z(:), v);
+ sval = size (val);
+ i000 = sub2ind (sval, idx(:, 1), idx(:, 2), idx(:, 3));
+ i100 = sub2ind (sval, idx(:, 1)+1, idx(:, 2), idx(:, 3));
+ i010 = sub2ind (sval, idx(:, 1), idx(:, 2)+1, idx(:, 3));
+ i001 = sub2ind (sval, idx(:, 1), idx(:, 2), idx(:, 3)+1);
+ i101 = sub2ind (sval, idx(:, 1)+1, idx(:, 2), idx(:, 3)+1);
+ i011 = sub2ind (sval, idx(:, 1), idx(:, 2)+1, idx(:, 3)+1);
+ i110 = sub2ind (sval, idx(:, 1)+1, idx(:, 2)+1, idx(:, 3));
+ i111 = sub2ind (sval, idx(:, 1)+1, idx(:, 2)+1, idx(:, 3)+1 );
+ Bx = frac(:, 1);
+ By = frac(:, 2);
+ Bz = frac(:, 3);
+ Dx = ...
+ val( i000 ) .* -1 .* (1 .- By) .* (1 .- Bz) .+ ...
+ val( i100 ) .* (1 .- By) .* (1 .- Bz) .+ ...
+ val( i010 ) .* -1 .* By .* (1 .- Bz) .+ ...
+ val( i001 ) .* -1 .* (1 .- By) .* Bz .+ ...
+ val( i011 ) .* -1 .* By .* Bz .+ ...
+ val( i101 ) .* (1 .- By) .* Bz .+ ...
+ val( i110 ) .* By .* (1 .- Bz) .+ ...
+ val( i111 ) .* By .* Bz;
+ Dy = ...
+ val( i000 ) .* (1 .- Bx) .* -1 .* (1 .- Bz) .+ ...
+ val( i100 ) .* Bx .* -1 .* (1 .- Bz) .+ ...
+ val( i010 ) .* (1 .- Bx) .* (1 .- Bz) .+ ...
+ val( i001 ) .* (1 .- Bx) .* -1 .* Bz .+ ...
+ val( i011 ) .* (1 .- Bx) .* Bz .+ ...
+ val( i101 ) .* Bx .* -1 .* Bz .+ ...
+ val( i110 ) .* Bx .* (1 .- Bz) .+ ...
+ val( i111 ) .* Bx .* Bz;
+ Dz = ...
+ val( i000 ) .* (1 .- Bx) .* (1 .- By) .* -1 .+ ...
+ val( i100 ) .* Bx .* (1 .- By) .* -1 .+ ...
+ val( i010 ) .* (1 .- Bx) .* By .* -1 .+ ...
+ val( i001 ) .* (1 .- Bx) .* (1 .- By) .+ ...
+ val( i011 ) .* (1 .- Bx) .* By + ...
+ val( i101 ) .* Bx .* (1 .- By) .+ ...
+ val( i110 ) .* Bx .* By .* -1 .+ ...
+ val( i111 ) .* Bx .* By;
+endfunction
+
+function [idx, frac] = cube_idx(x, y, z, v)
+ idx = zeros (size (v));
+ frac = zeros (size (v));
+ idx(:, 2) = lookup (x(2:end-1), v(:, 1)) + 1;
+ frac(:, 2) = (v(:, 1) - x(idx(:, 2)) )...
+ ./ (x(idx(:, 2)+1) - x(idx(:, 2)));
+ idx(:, 1) = lookup (y(2:end-1), v(:, 2)) + 1;
+ frac(:, 1) = (v(:, 2) - y(idx(:, 1))) ...
+ ./ (y(idx(:, 1)+1) - y(idx(:, 1)));
+ idx(:, 3) = lookup (z(2:end-1), v(:, 3)) + 1;
+ frac(:, 3) = (v(:, 3) - z(idx(:, 3))) ...
+ ./ (z(idx(:, 3)+1) - z(idx(:, 3)));
+endfunction
git://git.creatis.insa-lyon.fr / CreaPhase.git / blobdiff