1vbo_rendering(3)                     Coin                     vbo_rendering(3)
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NAME

6       vbo_rendering - Vertex array and VBO rendering in Coin Coin 2.5 added
7       improved support for OpenGL vertex array and VBO rendering. This might
8       lead to major rendering performance improvements compared to the old
9       rendering code. The new rendering code has been added for the
10       SoIndexedFaceSet, SoVRMLIndexedFaceSet, SoIndexedLineSet,
11       SoVRMLIndexedLineSet, SoPointSet and SoVRMLPointSet nodes.
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13       To take advantage of the improved performance vertex array and VBO
14       rendering yields, you'll need to organize your vertex data in a way
15       that makes it possible to render it with OpenGL vertex arrays. OpenGL
16       vertex array rendering does not support multiple index arrays, so all
17       your vertex data (coordinates, normals, colors and texture coordinates)
18       must use the same index array; or use OVERALL binding. For the indexed
19       nodes, this means that PER_VERTEX_INDEXED and OVERALL are the only
20       supported bindings for materials, normals and texture coordinates. When
21       PER_VERTEX_INDEXED binding is used, the corresponding index field
22       should by empty. This will signal the shape to use the coordIndex field
23       for indices. Below is an example scene graph that will be rendered
24       using vertex arrays:
25
26         NormalBinding { value PER_VERTEX_INDEXED }
27         Coordinate3 {
28           point [
29             0 0 0, # 0
30             1 0 0, # 1
31             2 0 0, # 2
32             0 1 0, # 3
33             1 1 0, # 4
34             2 1 0, # 5
35             0 2 0, # 6
36             1 2 0, # 7
37             2 2 0, # 8
38
39             2 0  0, # 9
40             2 0 -1, # 10
41             2 1  0, # 11
42             2 1 -1, # 12
43             2 2  0, # 13
44             2 2 -1  # 14
45           ]
46         }
47         Normal {
48           vector [
49             0 0 1, # 0
50             0 0 1, # 1
51             0 0 1, # 2
52             0 0 1, # 3
53             0 0 1, # 4
54             0 0 1, # 5
55             0 0 1, # 6
56             0 0 1, # 7
57             0 0 1, # 8
58
59             1 0 0,  # 9
60             1 0 0,  # 10
61             1 0 0,  # 11
62             1 0 0,  # 12
63             1 0 0,  # 13
64             1 0 0   # 14
65           ]
66         }
67
68         IndexedFaceSet {
69           coordIndex [
70             0, 1, 4, 3, -1,
71             1, 2, 5, 4, -1,
72             3, 4, 7, 6, -1,
73             4, 5, 8, 7, -1,
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75             9, 10, 12, 11, -1,
76             11, 12, 14, 13, -1
77           ]
78           normalIndex [ ] # = use coordIndex
79         }
80         .fi
81
82       Please note that since only one index array can be used, it might be necessary to supply duplicate normals and coordinates to meet this requirement.
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84       Also, if normals are needed, you have to supply them. A shape with autogenerated normals can't be rendered using vertex arrays (since a single coordinate might get multiple normals).
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86       The PointSet nodes can always be rendered using vertex arrays since these nodes haven't got index arrays, and the only bindings supported are PER_VERTEX and OVERALL.
87
88       If it's inconvenient to create vertex array ready scene graphs directly from your application, it's also possible to use SoReorganizeAction to reorganize the geometry before rendering.
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92Version 2.5.0                   Tue Nov 8 2011                vbo_rendering(3)
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