1vbo_rendering(3Version)                                vbo_rendering(3Version)
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NAME

6       vbo_rendering - Vertex array and VBO rendering in Coin
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8       Coin 2.5 added improved support for OpenGL vertex array and VBO
9       rendering. This might lead to major rendering performance improvements
10       compared to the old rendering code. The new rendering code has been
11       added for the SoIndexedFaceSet, SoVRMLIndexedFaceSet, SoIndexedLineSet,
12       SoVRMLIndexedLineSet, SoPointSet and SoVRMLPointSet nodes.
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14       To take advantage of the improved performance vertex array and VBO
15       rendering yields, you'll need to organize your vertex data in a way
16       that makes it possible to render it with OpenGL vertex arrays. OpenGL
17       vertex array rendering does not support multiple index arrays, so all
18       your vertex data (coordinates, normals, colors and texture coordinates)
19       must use the same index array; or use OVERALL binding. For the indexed
20       nodes, this means that PER_VERTEX_INDEXED and OVERALL are the only
21       supported bindings for materials, normals and texture coordinates. When
22       PER_VERTEX_INDEXED binding is used, the corresponding index field
23       should by empty. This will signal the shape to use the coordIndex field
24       for indices. Below is an example scene graph that will be rendered
25       using vertex arrays:
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27       NormalBinding { value PER_VERTEX_INDEXED }
28       Coordinate3 {
29         point [
30           0 0 0, # 0
31           1 0 0, # 1
32           2 0 0, # 2
33           0 1 0, # 3
34           1 1 0, # 4
35           2 1 0, # 5
36           0 2 0, # 6
37           1 2 0, # 7
38           2 2 0, # 8
39
40           2 0  0, # 9
41           2 0 -1, # 10
42           2 1  0, # 11
43           2 1 -1, # 12
44           2 2  0, # 13
45           2 2 -1  # 14
46         ]
47       }
48       Normal {
49         vector [
50           0 0 1, # 0
51           0 0 1, # 1
52           0 0 1, # 2
53           0 0 1, # 3
54           0 0 1, # 4
55           0 0 1, # 5
56           0 0 1, # 6
57           0 0 1, # 7
58           0 0 1, # 8
59
60           1 0 0,  # 9
61           1 0 0,  # 10
62           1 0 0,  # 11
63           1 0 0,  # 12
64           1 0 0,  # 13
65           1 0 0   # 14
66         ]
67       }
68
69       IndexedFaceSet {
70         coordIndex [
71           0, 1, 4, 3, -1,
72           1, 2, 5, 4, -1,
73           3, 4, 7, 6, -1,
74           4, 5, 8, 7, -1,
75
76           9, 10, 12, 11, -1,
77           11, 12, 14, 13, -1
78         ]
79         normalIndex [ ] # = use coordIndex
80       }
81
82       Please note that since only one index array can be used, it might be
83       necessary to supply duplicate normals and coordinates to meet this
84       requirement.
85
86       Also, if normals are needed, you have to supply them. A shape with
87       autogenerated normals can't be rendered using vertex arrays (since a
88       single coordinate might get multiple normals).
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90       The PointSet nodes can always be rendered using vertex arrays since
91       these nodes haven't got index arrays, and the only bindings supported
92       are PER_VERTEX and OVERALL.
93
94       If it's inconvenient to create vertex array ready scene graphs directly
95       from your application, it's also possible to use SoReorganizeAction to
96       reorganize the geometry before rendering.
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100Coin                                2.5.0"             vbo_rendering(3Version)
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