DRAWSPHERE Draw a sphere as a mesh.
drawSphere(SPHERE)
Where SPHERE = [XC YC ZC R], draw the sphere centered on the point with
coordinates [XC YC ZC] and with radius R, using a quad mesh.
drawSphere(CENTER, R)
Where CENTER = [XC YC ZC], specifies the center and the radius with two
arguments.
drawSphere(XC, YC, ZC, R)
Specifiy sphere center and radius as four arguments.
drawSphere(..., NAME, VALUE);
Specifies one or several options using parameter name-value pairs.
Available options are usual drawing options, as well as:
'nPhi' the number of arcs used for drawing the meridians
'nTheta' the number of circles used for drawing the parallels
H = drawSphere(...)
Return a handle to the graphical object created by the function.
[X Y Z] = drawSphere(...)
Return the coordinates of the vertices used by the sphere. In this
case, the sphere is not drawn.
Example
% Draw four spheres with different centers
figure(1); clf; hold on;
drawSphere([10 10 30 5]);
drawSphere([20 30 10 5]);
drawSphere([30 30 30 5]);
drawSphere([30 20 10 5]);
view([-30 20]); axis equal; l = light;
% Draw sphere with different settings
figure(1); clf;
drawSphere([10 20 30 10], 'linestyle', ':', 'facecolor', 'r');
axis([0 50 0 50 0 50]); axis equal;
l = light;
% The same, but changes style using graphic handle
figure(1); clf;
h = drawSphere([10 20 30 10]);
set(h, 'linestyle', ':');
set(h, 'facecolor', 'r');
axis([0 50 0 50 0 50]); axis equal;
l = light;
% Draw a sphere with high resolution
figure(1); clf;
h = drawSphere([10 20 30 10], 'nPhi', 360, 'nTheta', 180);
l = light; view(3);
See also
spheres, circles3d, sphere, drawEllipsoid0001 function varargout = drawSphere(varargin) 0002 %DRAWSPHERE Draw a sphere as a mesh. 0003 % 0004 % drawSphere(SPHERE) 0005 % Where SPHERE = [XC YC ZC R], draw the sphere centered on the point with 0006 % coordinates [XC YC ZC] and with radius R, using a quad mesh. 0007 % 0008 % drawSphere(CENTER, R) 0009 % Where CENTER = [XC YC ZC], specifies the center and the radius with two 0010 % arguments. 0011 % 0012 % drawSphere(XC, YC, ZC, R) 0013 % Specifiy sphere center and radius as four arguments. 0014 % 0015 % drawSphere(..., NAME, VALUE); 0016 % Specifies one or several options using parameter name-value pairs. 0017 % Available options are usual drawing options, as well as: 0018 % 'nPhi' the number of arcs used for drawing the meridians 0019 % 'nTheta' the number of circles used for drawing the parallels 0020 % 0021 % H = drawSphere(...) 0022 % Return a handle to the graphical object created by the function. 0023 % 0024 % [X Y Z] = drawSphere(...) 0025 % Return the coordinates of the vertices used by the sphere. In this 0026 % case, the sphere is not drawn. 0027 % 0028 % Example 0029 % % Draw four spheres with different centers 0030 % figure(1); clf; hold on; 0031 % drawSphere([10 10 30 5]); 0032 % drawSphere([20 30 10 5]); 0033 % drawSphere([30 30 30 5]); 0034 % drawSphere([30 20 10 5]); 0035 % view([-30 20]); axis equal; l = light; 0036 % 0037 % % Draw sphere with different settings 0038 % figure(1); clf; 0039 % drawSphere([10 20 30 10], 'linestyle', ':', 'facecolor', 'r'); 0040 % axis([0 50 0 50 0 50]); axis equal; 0041 % l = light; 0042 % 0043 % % The same, but changes style using graphic handle 0044 % figure(1); clf; 0045 % h = drawSphere([10 20 30 10]); 0046 % set(h, 'linestyle', ':'); 0047 % set(h, 'facecolor', 'r'); 0048 % axis([0 50 0 50 0 50]); axis equal; 0049 % l = light; 0050 % 0051 % % Draw a sphere with high resolution 0052 % figure(1); clf; 0053 % h = drawSphere([10 20 30 10], 'nPhi', 360, 'nTheta', 180); 0054 % l = light; view(3); 0055 % 0056 % 0057 % See also 0058 % spheres, circles3d, sphere, drawEllipsoid 0059 0060 % --------- 0061 % author: David Legland 0062 % INRA - TPV URPOI - BIA IMASTE 0063 % created the 17/02/2005 0064 % 0065 0066 % HISTORY 0067 % 2006-05-19 use centered sphere with radius 1 when no input specified 0068 % 2007-01-04 typo 0069 % 2010-11-08 code cleanup, add doc 0070 0071 % Check if axes handle is specified 0072 if isAxisHandle(varargin{1}) 0073 hAx = varargin{1}; 0074 varargin(1)=[]; 0075 elseif nargout ~= 3 0076 hAx = gca; 0077 end 0078 0079 % process input options: when a string is found, assumes this is the 0080 % beginning of options 0081 options = {'FaceColor', 'g', 'LineStyle', 'none'}; 0082 for i = 1:length(varargin) 0083 if ischar(varargin{i}) 0084 if length(varargin) == 1 0085 options = {'FaceColor', varargin{1}, 'LineStyle', 'none'}; 0086 else 0087 options = [options(1:end) varargin(i:end)]; 0088 end 0089 varargin = varargin(1:i-1); 0090 break; 0091 end 0092 end 0093 0094 % Parse the input (try to extract center coordinates and radius) 0095 if isempty(varargin) 0096 % no input: assumes unit sphere 0097 xc = 0; yc = 0; zc = 0; 0098 r = 1; 0099 0100 elseif length(varargin) == 1 0101 % one argument: concatenates center and radius 0102 sphere = varargin{1}; 0103 xc = sphere(:,1); 0104 yc = sphere(:,2); 0105 zc = sphere(:,3); 0106 r = sphere(:,4); 0107 0108 elseif length(varargin) == 2 0109 % two arguments, corresponding to center and radius 0110 center = varargin{1}; 0111 xc = center(1); 0112 yc = center(2); 0113 zc = center(3); 0114 r = varargin{2}; 0115 0116 elseif length(varargin) == 4 0117 % four arguments, corresponding to XC, YX, ZC and R 0118 xc = varargin{1}; 0119 yc = varargin{2}; 0120 zc = varargin{3}; 0121 r = varargin{4}; 0122 else 0123 error('drawSphere: please specify center and radius'); 0124 end 0125 0126 % number of meridians 0127 nPhi = 32; 0128 ind = find(strcmpi('nPhi', options(1:2:end))); 0129 if ~isempty(ind) 0130 ind = ind(1); 0131 nPhi = options{2*ind}; 0132 options(2*ind-1:2*ind) = []; 0133 end 0134 0135 % number of parallels 0136 nTheta = 16; 0137 ind = find(strcmpi('nTheta', options(1:2:end))); 0138 if ~isempty(ind) 0139 ind = ind(1); 0140 nTheta = options{2*ind}; 0141 options(2*ind-1:2*ind) = []; 0142 end 0143 0144 % compute spherical coordinates 0145 theta = linspace(0, pi, nTheta+1); 0146 phi = linspace(0, 2*pi, nPhi+1); 0147 0148 % convert to cartesian coordinates 0149 sintheta = sin(theta); 0150 x = xc + cos(phi')*sintheta*r; 0151 y = yc + sin(phi')*sintheta*r; 0152 z = zc + ones(length(phi),1)*cos(theta)*r; 0153 0154 % Process output 0155 if nargout == 0 0156 % no output: draw the sphere 0157 surf(hAx, x, y, z, options{:}); 0158 0159 elseif nargout == 1 0160 % one output: compute 0161 varargout{1} = surf(hAx, x, y, z, options{:}); 0162 0163 elseif nargout == 3 0164 varargout{1} = x; 0165 varargout{2} = y; 0166 varargout{3} = z; 0167 end 0168