Just one more example. To run this example you will need the following file(s): ./fem.box. If the example requires more than one file, then you should put them into the same directory. You can then launch Box/Boxer with box -l g ./fem.box or boxer ./fem.box.
//!BOXER:VERSION:0:1:1 include "g" GUI = Void Window@GUI[] //!BOXER:REFPOINTS:BEGIN gui1 = Point[.x=22.6463104326, .y=20.1530612245] gui2 = Point[.x=28.6162436548, .y=12.297979798] gui3 = Point[.x=49.1240447419, .y=12.0103472727] gui4 = Point[.x=54.4623687097, .y=20.1621436364] gui5 = Point[.x=31.4164974619, .y=25.254040404] gui6 = Point[.x=45.4177664975, .y=25.254040404] gui7 = Point[.x=39.7184263226, .y=39.2679163636] gui8 = Point[.x=42.1083756345, .y=19.9191919192] gui9 = Point[.x=10.9408632, .y=14.7867554639] gui10 = Point[.x=16.3969543147, .y=27.0323232323] gui11 = Point[.x=17.9243654822, .y=4.42272727273] gui12 = Point[.x=41.7408808, .y=2.3788769802] gui13 = Point[.x=64.1408501455, .y=5.65008293194] gui14 = Point[.x=67.4499864, .y=16.8216725773] gui15 = Point[.x=59.5590339273, .y=28.7857752356] gui16 = Point[.x=40.3408577818, .y=17.4899572539] gui17 = Point[.x=27.7408657455, .y=33.107827644] gui18 = Point[.x=38.1772249091, .y=32.3451125131] gui19 = Point[.x=51.9226735636, .y=34.1247811518] gui20 = Point[.x=6.0692602623, .y=8.17327484536] gui21 = Point[.x=-1.38793373941, .y=47.8541585567] gui22 = Point[.x=77.9399739409, .y=-2.08636485187] //!BOXER:REFPOINTS:END include "arrows" w = Window[][ BBox[gui21, gui22] b = 0.15 // border bd = Border[b, color.black] s1 = Style[bd] s2 = StrokeStyle[bd, Dash[2]] s3 = StrokeStyle[bd, Dash[0.5]] Lines[s3, gui10, gui1, gui9, gui2, gui11, gui12, gui2; gui5, gui10, gui9, gui11; gui4, gui14, gui3, gui13, gui12, gui3; gui4, gui15, gui14, gui13; gui6, gui15; gui17, gui5, gui18, gui6, gui19] Circles[color.white, gui16, 25, 10; 37, 20] c1 = Color[color.green, .a=0.5] c2 = Color[c1, .Darker[0.4], .a=0.5] c3 = Color[c1, .a=0.5] c4 = Color[c1, .Darker[0.8], .a=0.5] Poly[s1, c1, gui2, gui3, gui4, gui6, gui5, gui1] Poly[s1, c2, gui1, gui7, gui2] Poly[s1, c3, gui2, gui7, gui3] Poly[s1, c4, gui3, gui7, gui4] Line[s2, gui5, gui7, gui6] center = Point[gui8, .x=Point[gui7].x] Lines[c = center, s2, c, gui7; c, gui1; c, gui2; c, gui3; c, gui4; c, gui5; c, gui6] Circles[center, 2*b, color.black; gui7] color.black ax = gui20 + (10, 0), az = gui20 + (0, 10), ay = gui20 + (3, 5) Lines[0.25, gui20, Scale[0.8], arrow, ax; gui20, arrow, az; gui20, Scale[0.6], arrow, ay] Texts[Font["times-italic", 3.4] "e_{i }(P) = 1", gui7, From[(0.5, -0.1)]; "P", center, From[(0.5, 1.3)]; From[(-0.2, 0)], "x", ax; "y", ay; From[(0.5, 0)], "e_{i }(x, y)", az] ] GUI[w] \ Window["rgb24", .Origin[gui21], ss = Point[gui22] - Point[gui21], (ss.x, ss.y), .Res[Dpi[150]]][ Put[w] .Save["fem.png"] ]