function NrbsSrf2IGES(NrbSurf, OutName, BaseDir)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% This function will take a NURBS surface and convert it to an IGES file
% using Entity type 128 (Rational B-Spline Surface Entity). Some things
% that should be noted are:
%
% 1 - This is a very speciallized IGES converter and ONLY outputs NURBS
% surfaces.
% 2 - I make no attempt to work with different versions of IGES.
% 3 - To make the output more readable and easy I wasted a lot of space
% 4 - All the spacing is done manually so if any of the G section words
% are changed the spacing will need to be fixed.
% 5 - Changing the output that of Rational B-Spline Curves should be
% relatively easy. Other Entities will require significantly more work.
%
% Created: 8 - 2006 Michael Fassbind
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
clear P;
%% to do examples need to comment first and last line of this script
% % Example 1 The basic test surface from the free NURBS toolbox
% BaseDir = '.\';
% load([BaseDir 'TestSRF']);
% OutName = 'NurbSrf.igs';
% NrbSurf = srf;
% nrbplot(NrbSurf, [20 20]);
% % Example 2 The basic Ruled surface from the free NURBS toolbox
% BaseDir = '.\';
% load([BaseDir 'TSTRuled']);
% OutName = 'TSTRuld.igs';
% NrbSurf = srf;
% nrbplot(NrbSurf, [20 20]);
nam = 'NrbSurf_Output';
%**************************information*********************************
SLine = 'Matlab Nurbs converted -> IGES file. Written by Mike F. ';
%GGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGGG
G{1,1} = ','; % Parameter Deliminator Character
G{2,1} = ';'; % Record Delimiter Character
G{3,1} = nam; % Product ID from Sender
G{4,1} = OutName; % File Name
G{5,1} = 'MatNrb'; % System ID
G{6,1} = 'Matlab -> IGES v3.0 Aug 2006'; % Pre-processor Version
G{7,1} = 16; % Number of Bits for Integers
G{8,1} = 6; % Single Precision Magnitude
G{9,1} = 15; % Single Precision Significance
G{10,1}= 13; % Double Precision Magnitude
G{11,1}= 15; % Double Precision Significance
G{12,1}= nam; % Product ID for Receiver
G{13,1}= 1.00000; % Model Space Scale
G{14,1}= 3; % Unit Flag (1 = inches, 3 = look to index 15 name)
G{15,1}= 'MM'; % Units (Inches = "INCH")
G{16,1}= 8; % Maximum Number of Line Weights
G{17,1}= 0.0160000; % Size of Maximum Line Width
G{18,1}= 'Today'; % Date and Time Stamp ** fix me **
G{19,1}= 0.000100000; % Minimum User-intended Resolution
G{20,1}= 300.000; % Approximate Maximum Coordinate
G{21,1}= 'Michael Fassbind: mikefazz@gmail.com'; % Name of Author
G{22,1}= 'Puget Sound VA RR&D'; % Author's Organization
G{23,1}= 11; % - USPRO/IPO-100 (IGES 5.2) [USPRO93]'; % IGES Version Number ** prob not right **
G{24,1}= 3; % - ANSI'; % Drafting Standard Code
G{25,1}= 'Today of course'; % Model Creation/Change Date
%DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDd
sz_i = size(NrbSurf.knots{1,1});
sz_j = size(NrbSurf.knots{1,2});
sz_w = size(NrbSurf.coefs);
N_pnts = (sz_w(1,2)*sz_w(1,3));
NumLines = 1 + sz_i(1,2) + sz_j(1,2) + N_pnts + N_pnts + 1;
D{1,1} = 128; % Entity Type. 128 is Rational B-Spline surface
D{2,1} = 1; % Data Start line (only one entity so = 1)
D{3,1} = 0; % Structure
D{4,1} = 1; % Line Font Pattern (1= Solid)
D{5,1} = 0; % Level
D{6,1} = 0; % View
D{7,1} = 0; % Transformation Matrix
D{8,1} = 0; % Label Display
D{9,1} = 0; % Blank Status (0 = Visible)
D{10,1}= 0; % Subord. Entity Switch (0 = Independant)
D{11,1}= 0; % Entity Use Flag (0 = Geometry)
D{12,1}= 1; % Hierarchy ( 1 = Global defer)
D{13,1}= 0; % Line Weight Number
D{14,1}= NumLines; % Data end line
D{15,1}= 0; % Form Number (9 = General Quadratic Surface), 0 = none of above (1-9) options
%PPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP
P{1,1} = 128; % Entity Type. 128 = Rational spline surface
P{2,1} = NrbSurf.number(1,1)-1; % Number of points in u direction (doesn't work without -1)
P{3,1} = NrbSurf.number(1,2)-1; % Number of points in v direction
P{4,1} = NrbSurf.order(1,1)-1; % Degree_u (degree = order -1)
P{5,1} = NrbSurf.order(1,2)-1; % Degree_v
P{6,1} = 0; % PROP1 Closed_u (0 = Not Closed)
P{7,1} = 0; % PROP2 Closed_v (0 = Not Closed) ****change to 1 for FEA Limb****
P{8,1} = 0; % PROP3 (1 = Polynomial i.e. all weights equal), 0 = rational
P{9,1} = 0; % PROP4 1st Direction periodicity (0 = Non-periodic)
P{10,1}= 0; % PROP5 2nd Direction periodicity (0 = Non-periodic)
%-----------------Knots----------------
% It looks like we need to have integers and not floating point numbers for
% the knot values
% must add a superfolous 0 and 1 to front and back of each knot sequence
%----U----
% P{i+11,1} = NrbSurf.knots{1,2}(1,1);
for i = 1:sz_i(1,2)
tmp1{i,1} = NrbSurf.knots{1,1}(1,i);
end
P = [P;tmp1];
% P = [P; NrbSurf.knots{1,1}(1,i)];
%----V----
for j = 1:sz_j(1,2)
tmp2{j,1} = NrbSurf.knots{1,2}(1,j);
end
P = [P;tmp2];
% P = [P; NrbSurf.knots{1,2}(1,j)];
%----------------Weights---------------
k=1;
for v=1:sz_w(1,3)
for u=1:sz_w(1,2)
tmp3{k,1} = NrbSurf.coefs(4,u,v); %**This should be fixed if ever want non-uniform splines**
k=k+1;
end
end
P = [P; tmp3];
clear tmp1 tmp2 tmp3
%************************Data export to file*******************************
% All lines must have exactly 80 characters across
filnam = [BaseDir OutName];
fid=fopen(filnam, 'w');
%------S Line information (The initial line to get things started)---------
% fprintf(fid,
% '*********|*********|*********|*********|*********|*********|*********|*********|\n'); 80 Characters for measurment
Sln =1;
fprintf(fid, '%s S%07.f\n', SLine, Sln);
%---------------G Line information (Header infomation)--------------------
Gln=1;
for i = 1:25 % Number of characters after each one
tmp = str2mat(G{i,1});
len=size(tmp);
G{i,2} = len(1,2);
G{i,3} = ischar(G{i,1}); % 1 = yes, 0 = no
end
fprintf(fid, '%1.0fH%s,', G{1,2}, G{1,1}); % 1
fprintf(fid, '%1.0fH%s,', G{2,2}, G{2,1});
fprintf(fid, '%2.0fH%s,', G{3,2}, G{3,1});
fprintf(fid, '%2.0fH%s, G%07.f\n', G{4,2}, G{4,1}, Gln); Gln=Gln+1;
fprintf(fid, '%1.0fH%s,', G{5,2}, G{5,1}); % 5
fprintf(fid, '%2.0fH%s,', G{6,2}, G{6,1});
fprintf(fid, '%2.0f,', G{7,1});
fprintf(fid, '%2.0f,', G{8,1});
fprintf(fid, '%2.0f,', G{9,1});
fprintf(fid, '%2.0f,', G{10,1}); % 10
fprintf(fid, '%2.0f, G%07.f\n', G{11,1}, Gln); Gln=Gln+1;
fprintf(fid, '%2.0fH%s,', G{12,2}, G{12,1});
fprintf(fid, '%5.2f,', G{13,1});
fprintf(fid, '%2.0f,', G{14,1});
fprintf(fid, '%2.0fH%s,', G{15,2}, G{15,1}); % 15
fprintf(fid, '%2.0f,', G{16,1});
fprintf(fid, '%7.4f,', G{17,1});
fprintf(fid, '%2.0fH%s,', G{18,2}, G{18,1});
fprintf(fid, '%5.5f, G%07.f\n', G{19,1}, Gln); Gln=Gln+1;
fprintf(fid, '%2.0f,', G{20,1}); % 20
fprintf(fid, '%2.0fH%s, G%07.f\n', G{21,2}, G{21,1}, Gln); Gln=Gln+1;
fprintf(fid, '%2.0fH%s, G%07.f\n', G{22,2}, G{22,1}, Gln); Gln=Gln+1;
fprintf(fid, '%2.0f,', G{23,1});
fprintf(fid, '%2.0f,', G{24,1});
fprintf(fid, '%2.0fH%s; G%07.f\n', G{25,2}, G{25,1}, Gln);
%------------------D Line information (Data information)-------------------
Dln=1;
% Doing this with only one entity...
fprintf(fid, '%8.0f%8.0f%8.0f%8.0f%8.0f%8.0f%8.0f 1D%07.f\n',...
D{1,1}, D{2,1}, D{3,1}, D{4,1}, D{5,1}, D{6,1}, D{7,1}, Dln);Dln=Dln+1;
fprintf(fid, '%8.0f%8.0f%8.0f%8.0f%8.0f D%07.f\n',...
D{1,1},D{12,1},D{13,1},D{14,1},D{15,1}, Dln);
%-----------------P Line information (All the data)-----------------------
Pln=1;
fprintf(fid, '%3.0f, %4.0f, %4.0f, %1.0f, %1.0f, ',...
P{1,1}, P{2,1}, P{3,1}, P{4,1}, P{5,1});
fprintf(fid, '%1.0f, %1.0f, %1.0f, %1.0f, %1.0f, 1P%07.f\n',...
P{6,1}, P{7,1}, P{8,1}, P{9,1}, P{10,1}, Pln); Pln=Pln+1;
len = size(P);
%-----------------Knots and Weights
st=1;
for i =11:len(1,1)
fprintf(fid, '%7.6f, 1P%07.f\n', P{i,1}, Pln); Pln=Pln+1;
end
%------------------Coefficients------------------------------
for U = 1:sz_w(1,3)
for V = 1:sz_w(1,2)
fprintf(fid, '%010.6f, %010.6f, %010.6f, ', ...
NrbSurf.coefs(1,V,U), NrbSurf.coefs(2,V,U), NrbSurf.coefs(3,V,U));
fprintf(fid, '1P%07.f\n', Pln);
Pln = Pln+1;
end
end
fprintf(fid, '0., 1., 0., 1.; 1P%07.f\n', Pln);% U(0), U(1),V(0),V(1)
%-----------------T Line information (Termination)------------------------
fprintf(fid, 'S%07.fG%07.fD%07.fP%07.f T0000001',...
Sln, Gln, Dln, Pln);
fclose(fid);
'Finished Export to IGES'
end
