Mercurial > octave
view scripts/plot/draw/isonormals.m @ 30236:628f26e122d9
maint: use rows() or columns() instead of size(__, 1 | 2) for clarity.
* ccolamd.cc, colamd.cc, Map.m, material.m, isocolors.m, isonormals.m,
isosurface.m, light.m, reducepatch.m, reducevolume.m, movfun.m, ilu.m,
__alltohandles__.m, dump_demos.m, mk-sparse-tst.sh:
Use rows() or columns() instead of size(__, 1 | 2) for clarity.
author | Rik <rik@octave.org> |
---|---|
date | Mon, 11 Oct 2021 20:09:59 -0700 |
parents | 7854d5752dd2 |
children | 796f54d4ddbf |
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######################################################################## ## ## Copyright (C) 2009-2021 The Octave Project Developers ## ## See the file COPYRIGHT.md in the top-level directory of this ## distribution or <https://octave.org/copyright/>. ## ## 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 ## <https://www.gnu.org/licenses/>. ## ######################################################################## ## -*- texinfo -*- ## @deftypefn {} {@var{vn} =} isonormals (@var{val}, @var{vert}) ## @deftypefnx {} {@var{vn} =} isonormals (@var{val}, @var{hp}) ## @deftypefnx {} {@var{vn} =} isonormals (@var{x}, @var{y}, @var{z}, @var{val}, @var{vert}) ## @deftypefnx {} {@var{vn} =} isonormals (@var{x}, @var{y}, @var{z}, @var{val}, @var{hp}) ## @deftypefnx {} {@var{vn} =} isonormals (@dots{}, "negate") ## @deftypefnx {} {} isonormals (@var{val}, @var{hp}) ## @deftypefnx {} {} isonormals (@var{x}, @var{y}, @var{z}, @var{val}, @var{hp}) ## @deftypefnx {} {} isonormals (@dots{}, "negate") ## ## Calculate normals to an isosurface. ## ## The vertex normals @var{vn} are calculated from the gradient of the ## 3-dimensional array @var{val} (size: lxmxn) containing the data for an ## isosurface geometry. The normals point towards smaller values in @var{val}. ## ## If called with one output argument @var{vn}, and the second input argument ## @var{vert} holds the vertices of an isosurface, then the normals @var{vn} ## are calculated at the vertices @var{vert} on a grid given by ## @code{[x, y, z] = meshgrid (1:l, 1:m, 1:n)}. The output argument ## @var{vn} has the same size as @var{vert} and can be used to set the ## @qcode{"VertexNormals"} property of the corresponding patch. ## ## If called with additional input arguments @var{x}, @var{y}, and @var{z}, ## which are 3-dimensional arrays with the same size as @var{val}, ## then the volume data is taken at these points. Instead of the vertex data ## @var{vert}, a patch handle @var{hp} can be passed to the function. ## ## If the last input argument is the string @qcode{"negate"}, compute the ## reverse vector normals of an isosurface geometry (i.e., pointed towards ## larger values in @var{val}). ## ## If no output argument is given, the property @qcode{"VertexNormals"} of ## the patch associated with the patch handle @var{hp} is changed directly. ## ## @seealso{isosurface, isocolors, smooth3} ## @end deftypefn function vn = isonormals (varargin) narg = nargin; negate = false; if (nargin > 2) if (ischar (varargin{end})) if (strcmpi (varargin{end}, "negate")) negate = true; narg -= 1; else error ("isonormals: Unknown option '%s'", varargin{end}); endif endif endif switch (narg) case 2 val = varargin{1}; vp = varargin{2}; x = 1:columns (val); y = 1:rows (val); z = 1:size (val, 3); case 5 x = varargin{1}; y = varargin{2}; z = varargin{3}; val = varargin{4}; vp = varargin{5}; otherwise print_usage (); endswitch if (isnumeric (vp) && columns (vp) == 3) pa = []; v = vp; elseif (isgraphics (vp, "patch")) pa = vp; v = get (pa, "Vertices"); else error ("isonormals: input must be a list of vertices or a patch handle"); endif if (negate) normals = __interp_cube__ ("isonormals", x, y, z, val, v, "normals"); else normals = -__interp_cube__ ("isonormals", x, y, z, val, v, "normals"); endif if (nargout == 0) if (! isempty (pa)) set (pa, "VertexNormals", normals); endif else vn = normals; endif endfunction %!demo %! function isofinish (hp) %! axis equal; %! set (hp, "VertexNormals", -get (hp, "VertexNormals")); # Revert normals %! shading interp; %! lighting gouraud; %! set (hp, "BackFaceLighting", "lit"); %! light (); %! endfunction %! %! N = 15; # Increase number of vertices in each direction %! iso = .4; # Change isovalue to .1 to display a sphere %! lin = linspace (0, 2, N); %! [x, y, z] = meshgrid (lin, lin, lin); %! val = (x-.5).^2 + (y-.5).^2 + (z-.5).^2; %! clf; %! %! subplot (2,2,1); %! view (-38, 20); %! [fac, vert, cdat] = isosurface (x, y, z, val, iso, y); %! hp = patch ("Faces", fac, "Vertices", vert, "FaceVertexCData", cdat); %! title ("without isonormals"); %! isofinish (hp); %! set (hp, "VertexNormalsMode", "auto"); # for Matlab compatibility %! %! subplot (2,2,2); %! view (-38, 20); %! hp = patch ("Faces", fac, "Vertices", vert, "FaceVertexCData", cdat); %! title ("patch modified by isonormals"); %! isonormals (x, y, z, val, hp); # Directly modify patch %! isofinish (hp); %! %! subplot (2,2,3); %! view (-38, 20); %! hp = patch ("Faces", fac, "Vertices", vert, "FaceVertexCData", cdat); %! vn = isonormals (x, y, z, val, vert); # Compute normals of isosurface %! set (hp, "VertexNormals", vn); # Manually set vertex normals %! title ('set "VertexNormals" from isonormals'); %! isofinish (hp); %! %! subplot (2,2,4); %! view (-38, 20); %! hp = patch ("Faces", fac, "Vertices", vert, "FaceVertexCData", cdat); %! isonormals (x, y, z, val, hp, "negate"); # Use reverse directly %! title ('patch modified by isonormals (..., "negate")'); %! isofinish (hp); %!shared x,y,z,val,vert %! [x, y, z] = meshgrid (0:.5:2, 0:.5:2, 0:.5:2); %! val = abs ((x-.5).^2 + (y-.3).^2 + (z-.4).^2); %! [fac, vert, cdat] = isosurface (x, y, z, val, .4, y); %!test %! vn = isonormals (x, y, z, val, vert); %! assert (size (vert), size (vn)); %!test %! np = isonormals (x, y, z, val, vert); %! nn = isonormals (x, y, z, val, vert, "negate"); %! assert (np, -nn); %!test %! [x,y,z] = meshgrid (-2:1:2, -2:1:2, -2:1:2); %! val = x.^2 + y.^2 + z.^2; %! [f,vert] = isosurface (x, y, z, val, 1); %! vn = isonormals (x, y, z, val, vert); %! dirn = vert ./ vn; %! assert (all (dirn(isfinite (dirn)) <= 0)); ## Test input validation %!error <Invalid call> isonormals () %!error <Invalid call> isonormals (1) %!error <Invalid call> isonormals (1,2,3) %!error <Invalid call> isonormals (1,2,3,4) %!error <Invalid call> isonormals (1,2,3,4,5,6) %!error <Unknown option 'foo'> isonormals (x, y, z, val, vert, "foo") %!error <must be a list of vertices> isonormals (1, {1}) %!error <must be a list of vertices> isonormals (1, [1 2 3 4]) %!error <must be a .* patch handle> isonormals (x, y, z, val, x) ## Test validation of private function __interp_cube__ %!error <X, Y, Z have unequal dimensions> isonormals ({x}, y, z, val, vert) %!error <X, Y, Z have unequal dimensions> isonormals (x, {y}, z, val, vert) %!error <X, Y, Z have unequal dimensions> isonormals (x, y, {z}, val, vert) %!error <X, Y, Z have unequal dimensions> isonormals (x, y, z(1), val, vert) %!error <X, Y, Z have unequal dimensions> isonormals (x(:), y(:), z, val, vert) %!error <VAL dimensions must match those of X, Y, and Z> isonormals (1, 2, 3, val, vert)