1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
// -----------------------------------------------------------------------------
//
// Gmsh GEO tutorial 8
//
// Post-processing and animations
//
// -----------------------------------------------------------------------------
// In addition to creating geometries and meshes, GEO scripts can also be used
// to manipulate post-processing datasets (called "views" in Gmsh).
// We first include `t1.geo' as well as some post-processing views:
Include "t1.geo";
Include "view1.pos";
Include "view1.pos";
Include "view4.pos";
// Gmsh can read post-processing views in various formats. Here the `view1.pos'
// and `view4.pos' files are in the Gmsh "parsed" format, which is interpreted
// directly by the GEO script parser. The parsed format should only be used for
// relatively small datasets of course: for larger datasets using e.g. MSH files
// is much more efficient.
// We then set some general options:
General.Trackball = 0;
General.RotationX = 0; General.RotationY = 0; General.RotationZ = 0;
General.Color.Background = White; General.Color.Foreground = Black;
General.Color.Text = Black;
General.Orthographic = 0;
General.Axes = 0; General.SmallAxes = 0;
// We also set some options for each post-processing view:
v0 = PostProcessing.NbViews-4;
v1 = v0+1; v2 = v0+2; v3 = v0+3;
View[v0].IntervalsType = 2;
View[v0].OffsetZ = 0.05;
View[v0].RaiseZ = 0;
View[v0].Light = 1;
View[v0].ShowScale = 0;
View[v0].SmoothNormals = 1;
View[v1].IntervalsType = 1;
View[v1].ColorTable = { Green, Blue };
View[v1].NbIso = 10;
View[v1].ShowScale = 0;
View[v2].Name = "Test...";
View[v2].Axes = 1;
View[v2].Color.Axes = Black;
View[v2].IntervalsType = 2;
View[v2].Type = 2;
View[v2].IntervalsType = 2;
View[v2].AutoPosition = 0;
View[v2].PositionX = 85;
View[v2].PositionY = 50;
View[v2].Width = 200;
View[v2].Height = 130;
View[v3].Visible = 0;
// You can save an MPEG movie directly by selecting `File->Export' in the
// GUI. Several predefined animations are setup, for looping on all the time
// steps in views, or for looping between views.
// But a script can be used to build much more complex animations, by changing
// options at run-time and re-rendering the graphics. Each frame can then be
// saved to disk as an image, and multiple frames can be encoded to form a
// movie. Below is an example of such a custom animation.
t = 0; // Initial step
// Loop on num from 1 to 3
For num In {1:3}
View[v0].TimeStep = t; // Set time step
View[v1].TimeStep = t;
View[v2].TimeStep = t;
View[v3].TimeStep = t;
t = (View[v0].TimeStep < View[v0].NbTimeStep-1) ? t+1 : 0; // Increment
View[v0].RaiseZ += 0.01/View[v0].Max * t; // Raise view v0
If (num == 3)
// Resize the graphics when num == 3, to create 640x480 frames
General.GraphicsWidth = General.MenuWidth + 640;
General.GraphicsHeight = 480;
EndIf
frames = 50;
// Loop on num2 from 1 to frames
For num2 In {1:frames}
// Incrementally rotate the scene
General.RotationX += 10;
General.RotationY = General.RotationX / 3;
General.RotationZ += 0.1;
// Sleep for 0.01 second
Sleep 0.01;
// Draw the scene (one could use `DrawForceChanged' instead to force the
// reconstruction of the vertex arrays, e.g. if changing element clipping)
Draw;
If (num == 3)
// Uncomment the following lines to save each frame to an image file (the
// `Print' command saves the graphical window; the `Sprintf' function
// permits to create the file names on the fly):
// Print Sprintf("t8-%02g.gif", num2);
// Print Sprintf("t8-%02g.ppm", num2);
// Print Sprintf("t8-%02g.jpg", num2);
EndIf
EndFor
If(num == 3)
// Here we could make a system call to generate a movie. For example,
// with whirlgif:
/*
System "whirlgif -minimize -loop -o t8.gif t8-*.gif";
*/
// with mpeg_encode (create parameter file first, then run encoder):
/*
Printf("PATTERN I") > "t8.par";
Printf("BASE_FILE_FORMAT PPM") >> "t8.par";
Printf("GOP_SIZE 1") >> "t8.par";
Printf("SLICES_PER_FRAME 1") >> "t8.par";
Printf("PIXEL HALF") >> "t8.par";
Printf("RANGE 10") >> "t8.par";
Printf("PSEARCH_ALG EXHAUSTIVE") >> "t8.par";
Printf("BSEARCH_ALG CROSS2") >> "t8.par";
Printf("IQSCALE 1") >> "t8.par";
Printf("PQSCALE 1") >> "t8.par";
Printf("BQSCALE 25") >> "t8.par";
Printf("REFERENCE_FRAME DECODED") >> "t8.par";
Printf("OUTPUT t8.mpg") >> "t8.par";
Printf("INPUT_CONVERT *") >> "t8.par";
Printf("INPUT_DIR .") >> "t8.par";
Printf("INPUT") >> "t8.par";
tmp = Sprintf("t8-*.ppm [01-%02g]", frames);
Printf(tmp) >> "t8.par";
Printf("END_INPUT") >> "t8.par";
System "mpeg_encode t8.par";
*/
// with mencoder:
/*
System "mencoder 'mf://*.jpg' -mf fps=5 -o t8.mpg -ovc lavc
-lavcopts vcodec=mpeg1video:vhq";
System "mencoder 'mf://*.jpg' -mf fps=5 -o t8.mpg -ovc lavc
-lavcopts vcodec=mpeg4:vhq";
*/
// with ffmpeg:
/*
System "ffmpeg -hq -r 5 -b 800 -vcodec mpeg1video
-i t8-%02d.jpg t8.mpg"
System "ffmpeg -hq -r 5 -b 800 -i t8-%02d.jpg t8.asf"
*/
EndIf
EndFor
|
