Présentation de 3D_58a.jps

/syracuse/bbgraf/albums/sections_planes_02/3D_58a.jpg
autocrop 15 setxunit %quadrillage marks -22 8 setxrange -8 18 setyrange %% le plan de base /P1 {-9 -5} def /P2 {4 -7} def /P3 {8.5 0} def /o {0 0 0} def /i {0 0 7} def /o' {0 0 14} def /M {-12 2} def /N {-7 -3} def /vect_I {15 cos 15 sin} def /vect_J {135 cos 135 sin .8 mulv} def /vect_K {0 1} def /xyz2xy { 3 dict begin /z exch def /y exch def /x exch def vect_I x mulv vect_J y mulv vect_K z mulv addv addv end } def [/I /O /O'] [i o o'] {xyz2xy} capply mapnp /r1 6 def /r2 1.5 def /ell [O r1 r2 0] def /ell' [O' r1 r2 0] def 0 ell epoint /A defpoint 0 ell' epoint /A' defpoint 180 ell epoint /B defpoint 180 ell' epoint /B' defpoint O M ell interdroiteell /m defpoint /m' defpoint O O' m paral I M interdroite /M' defpoint O O' m' paral I M interdroite /M" defpoint gsave .8 setlinewidth orange pointilles [m' M M"] ligne [m M'] ligne [m' M"] ligne grestore /dotscale {2 dup} def [I O O' M] {times} plot [M' M"] {times2} plot 1.2 setlinewidth -180 0 ell Ellipse ell' ellipse [A A'] ligne [B B'] ligne M N 1.5 hompoint N 1.2 trait gsave .8 setlinewidth pointilles 0 180 ell Ellipse [O O'] ligne grestore 2 setlinewidth [-12 P2 P1 xdpoint P2 P3] ligne 12 setfontsize setTimesItalic (I) I drtext (O) O drtext (O') O' drtext (d) 5 M N ydpoint urtext (M) M dltext % (N) N dltext