1 # Generate set of boxes resembling OCC logo and arranged in the shape of
2 # Penrose triangle on perspective view.
3 # The sample shows how the viewer can be manipulated to produce required
6 #Category: Visualization
7 #Title: Penrose triangle on perspective view
9 pload MODELING VISUALIZATION
11 # procedure to define box dimensions
16 set scale [expr $scale * $ratio]
17 return [list 1.8*$scale 1.8*$scale 1.3*$scale]
21 eval box b1 0 0 0 [defbox]
22 eval box b2 2 0 0 [defbox]
23 eval box b3 4 0 0 [defbox]
24 eval box b4 6 0 0 [defbox]
25 eval box b5 6 -1.5 0 [defbox]
26 eval box b6 6 -3 0 [defbox]
27 eval box b7 6 -4.5 0 [defbox]
28 eval box b8 6 -6 0 [defbox]
29 eval box b9 6 -6 1 [defbox]
30 eval box b10 6 -6 2 [defbox]
32 # cut last box by prisms created from the first two to make impression
33 # that it is overlapped by these on selected view (see vviewparams below)
36 prism p0 b1_5 12.3 -14 6.8
38 prism p1 b2_3 12 -14 6.8
42 # make some boxes hollow
43 for {set i 1} {$i <= 1} {incr i} {
44 set dim [bounding b$i -save xmin ymin zmin xmax ymax zmax]
45 set dx [dval xmax-xmin]
46 set x1 [dval xmin+0.1*$dx]
47 set x2 [dval ymin+0.1*$dx]
48 set x3 [dval zmin+0.1*$dx]
49 box bc $x1 $x2 $x3 0.8*$dx 0.8*$dx $dx
55 vinit Penrose w=1024 h=512
56 vbackground -color WHITE
57 vrenderparams -rayTrace -fsaa on -reflections off -shadows off
59 # set camera position and adjust lights
60 vcamera -persp -fovy 25
61 vviewparams -eye 14 -14 6.8 -up 0 0 1 -at 4 -4 0 -scale 70
64 vlight add directional direction 1 -2 -10 head 1 color white
65 vlight add directional direction 0 -10 0 head 1 color white
68 vdisplay b1 b2 b3 b4 b5 b6 b7 b8 b9 b10
70 # set colors like in boxes of on OCC logo
71 vsetcolor b1 0.8671875 0 0.16015625
72 vsetcolor b2 0.96484375 0.8671875 0
73 vsetcolor b3 0.609375 0.97734375 0.09375
74 vsetcolor b4 0.90234375 0 0.48046875
75 vsetcolor b5 0 0.48046875 0.73828125
76 vsetcolor b6 0.578125 0 0.48046875
77 vsetcolor b7 0.93359375 0.609375 0
78 vsetcolor b8 0 0.70703125 0.9296875
79 vsetcolor b9 0 0.64453125 0.48046875
80 vsetcolor b10 0 0.48046875 0.73828125
82 # set material to plastic for better look
83 for {set i 1} {$i <= 10} {incr i} {vsetmaterial b$i plastic}
85 vdrawtext label "Which\nbox\nis\ncloser\nto\nyou?" -pos 0 -6 -2 -color 0 0 0 -halign left -valign bottom -angle 0 -zoom 0 -height 40