IGESNotes by Paul Bourke
IGES stands for Initial Graphics Exchange Specification and was written by a panel for the National Bureau of Standards. The strongest argument for IGES is its high level of support by CAD packages running on the larger computer systems. IGES is both a 2D and 3D format. ExampleA simple example IGES file (so you may recognise one when you see it) is shown below. Each line is based upon a 80 character string, from the era of 80 character punch card readers from the computers of the 70's and 80's running early versions of FORTRAN. Data containing text strings are stored in so called "Hollerith" format, that is a number which is the length of the string, followed by an "H", followed by the string itself. For example the line after the header line below is: ", ; box+line.IGS box+line.IGS CGT v1.0 IGES 3.0 16 8 24 8". The character in column 73 determines the type of data on the line, this may be S, G, D, P, or T standing for Start, Global, Directory Entry, Parameter Data, and Terminate. IGES Start section created by Claris Graphics Translator v1.0 S 1 1H,,1H;,12Hbox+line.IGS,12Hbox+line.IGS,8HCGT v1.0,8HIGES 3.0,16,8,24,8,G 1 24,12Hbox+line.IGS,1.0,1,4HINCH,32000,1.6,13H910305.183439,,,3HIBB,3HWCPG 2 ,4,0; G 3 124 1 1 0 0 0 0 0 0 0 0 0D 1 124 0 0 1 0 0 0 D 2 124 2 1 0 0 0 0 0 0 1 1 0D 3 124 0 0 1 0 0 0 D 4 410 3 1 1 0 0 3 0 0 2 2 0D 5 410 0 0 1 0 0 0 D 6 124 4 1 0 0 0 0 0 0 0 0 0D 7 124 0 0 1 0 0 0 D 8 124 5 1 0 0 0 0 0 0 1 1 0D 9 124 0 0 1 0 0 0 D 10 410 6 1 1 0 0 9 0 0 2 2 0D 11 410 0 0 1 0 0 0 D 12 124 7 1 0 0 0 0 0 0 0 0 0D 13 124 0 0 1 0 0 0 D 14 124 8 1 0 0 0 0 0 0 1 1 0D 15 124 0 0 1 0 0 0 D 16 410 9 1 1 0 0 15 0 0 2 2 0D 17 410 0 0 1 0 0 0 D 18 124 10 1 0 0 0 0 0 0 0 0 0D 19 124 0 0 1 0 0 0 D 20 124 11 1 0 0 0 0 0 0 1 1 0D 21 124 0 0 1 0 0 0 D 22 410 12 1 1 0 0 21 0 0 2 2 0D 23 410 0 0 1 0 0 0 D 24 124 13 1 0 0 0 0 0 0 0 0 0D 25 124 0 0 1 0 0 0 D 26 124 14 1 0 0 0 0 0 0 1 1 0D 27 124 0 0 1 0 0 0 D 28 410 15 1 1 0 0 27 0 0 2 2 0D 29 410 0 0 1 0 0 0 D 30 124 16 1 0 0 0 0 0 0 0 0 0D 31 124 0 0 1 0 0 0 D 32 124 17 1 0 0 0 0 0 0 1 1 0D 33 124 0 0 1 0 0 0 D 34 410 18 1 1 0 0 33 0 0 2 2 0D 35 410 0 0 1 0 0 0 D 36 124 19 1 0 0 0 0 0 0 0 0 0D 37 124 0 0 1 0 0 0 D 38 124 20 1 0 0 0 0 0 0 1 1 0D 39 124 0 0 1 0 0 0 D 40 410 21 1 1 0 0 39 0 0 2 2 0D 41 410 0 0 1 0 0 0 D 42 304 22 1 1 0 0 0 0 0 1 0 0D 43 304 0 0 1 2 0 0 D 44 304 23 1 1 0 0 0 0 0 1 0 0D 45 304 0 0 1 2 0 0 D 46 304 24 1 1 0 0 0 0 0 1 0 0D 47 304 0 0 2 2 0 0 D 48 304 26 1 1 0 0 0 0 0 1 0 0D 49 304 0 0 1 2 0 0 D 50 304 27 1 1 0 0 0 0 0 1 0 0D 51 304 0 0 1 2 0 0 D 52 304 28 1 1 0 0 0 0 0 1 0 0D 53 304 0 0 1 2 0 0 D 54 110 29 1 1 1 5 1 0 0 0 0 0D 55 110 78 1 1 0 0 0 D 56 110 30 1 1 1 5 1 0 0 0 0 0D 57 110 78 1 1 0 0 0 D 58 110 31 1 1 1 5 1 0 0 0 0 0D 59 110 78 1 1 0 0 0 D 60 110 32 1 1 1 5 1 0 0 0 0 0D 61 110 78 1 1 0 0 0 D 62 110 33 1 1 1 5 1 0 0 0 0 0D 63 110 78 1 1 0 0 0 D 64 212 34 1 1 1 41 37 0 0 0 0 0D 65 212 0 1 2 0 0 0 D 66 406 36 1 0 0 0 0 0 0 1 2 0D 67 406 0 0 1 16 0 0 D 68 404 37 1 0 0 0 0 0 0 0 2 0D 69 404 0 0 2 0 0 0 D 70 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 1P 1 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 3P 2 410,2,1.0,0,0,0,0,0,0,0; 5P 3 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 7P 4 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 9P 5 410,3,1.0,0,0,0,0,0,0,0; 11P 6 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 13P 7 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 15P 8 410,4,2.0833333E-2,0,0,0,0,0,0,0; 17P 9 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 19P 10 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 21P 11 410,5,1.9999999E-2,0,0,0,0,0,0,0; 23P 12 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 25P 13 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 27P 14 410,6,2.0,0,0,0,0,0,0,0; 29P 15 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 31P 16 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 33P 17 410,7,1.0,0,0,0,0,0,0,0; 35P 18 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 37P 19 124,1.0,0.0,0.0,0.0,0.0,1.0,0.0,0.0,0.0,0.0,1.0,0.0; 39P 20 410,8,1.0,0,0,0,0,0,0,0; 41P 21 304,2,1.25E-1,4.1666667E-2,1H2; 43P 22 304,4,1.0,6.9444447E-2,1.25E-1,6.9444447E-2,1HA; 45P 23 304,6,1.0,6.9444447E-2,1.25E-1,6.9444447E-2,1.25E-1, 47P 24 6.9444447E-2,2H2A; 47P 25 304,2,1.25E-1,1.25E-1,1H2; 49P 26 304,2,6.9444447E-2,5.5555555E-2,1H2; 51P 27 304,2,2.5E-1,6.9444447E-2,1H2; 53P 28 110,1.125,9.375,0.0,3.25,9.375,0.0; 55P 29 110,3.25,9.375,0.0,3.25,8.375,0.0; 57P 30 110,3.25,8.375,0.0,1.125,8.375,0.0; 59P 31 110,1.125,8.375,0.0,1.125,9.375,0.0; 61P 32 110,1.25,8.25,0.0,3.625,8.875,0.0; 63P 33 212,1,12,1.0555555,1.6666667E-1,1,1.5707963,0.0,0,0,1.3888888, 65P 34 8.875,0.0,12Hbox and line; 65P 35 406,2,8.0,1.05E1; 67P 36 404,7,5,0.0,0.0,11,0.0,0.0,17,0.0,0.0,23,0.0,0.0,29,0.0,0.0,35, 69P 37 0.0,0.0,41,0.0,0.0,0,0,1,67; 69P 38 S 1G 3D 70P 38 T 1 |