Building Primitive Shapes
Motivation
Shapes are the building blocks of an X3D world. Primitive Shapes are standard building blocks:
- Box
- Cone
- Cylinder
- Sphere
- Text
- and more from the CADGeometry, Geometry2D, and Rendering component
Syntax: Shape
- A Shape node builds a shape
- appearance - color and texture
- geometry - form, or structure
XML Encoding
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<Shape>
<!-- appearance ... -->
<!-- geometry ... -->
<Shape>
Classic Encoding
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Shape {
appearance ...
geometry ...
}
Specifying appearance
- Shape appearance is described by appearance nodes
- For now, we’ll use nodes to create a shaded white appearance:
XML Encoding
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<Shape>
<Appearance>
<Material/>
</Appearance>
<!-- geometry ... -->
</Shape>
Classic Encoding
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Shape {
appearance Appearance {
material Material { }
}
geometry ...
}
Specifying geometry
Shape geometry is built with geometry nodes:
XML Encoding
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<Box ... />
<Cone ... />
<Cylinder ... />
<Sphere ... />
<Text ... />
Classic Encoding
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Box { ... }
Cone { ... }
Cylinder { ... }
Sphere { ... }
Text { ... }
- Geometry node fields control dimensions
- Dimensions usually in meters, but can be anything
A sample primitive shape
XML Encoding
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<?xml version="1.0" encoding="UTF-8"?>
<X3D profile='Full' version='4.0' xmlns:xsd='http://www.w3.org/2001/XMLSchema-instance' xsd:noNamespaceSchemaLocation='http://www.web3d.org/specifications/x3d-4.0.xsd'>
<Scene>
<Shape>
<Appearance>
<Material/>
</Appearance>
<Cylinder
radius='1.5'/>
</Shape>
</Scene>
</X3D>
Classic Encoding
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#X3D V4.0 utf8
# A cylinder
Shape {
appearance Appearance {
material Material { }
}
geometry Cylinder {
height 2.0
radius 1.5
}
}
Example
Building multiple shapes
- Shapes are built centered in the world
- A X3D file can contain multiple shapes
- Shapes overlap when built at the same location
A sample file with multiple shapes
XML Encoding
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<?xml version="1.0" encoding="UTF-8"?>
<X3D profile='Full' version='4.0' xmlns:xsd='http://www.w3.org/2001/XMLSchema-instance' xsd:noNamespaceSchemaLocation='http://www.web3d.org/specifications/x3d-4.0.xsd'>
<Scene>
<Shape>
<Appearance>
<Material/>
</Appearance>
<Box
size='1 1 1'/>
</Shape>
<Shape>
<Appearance>
<Material/>
</Appearance>
<Sphere
radius='0.7'/>
</Shape>
<!-- ... -->
</Scene>
</X3D>
Classic Encoding
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#X3D V4.0 utf8
Shape {
appearance Appearance {
material Material { }
}
geometry Box {
size 1.0 1.0 1.0
}
}
Shape {
appearance Appearance {
material Material { }
}
geometry Sphere {
radius 0.7
}
}
...
Example
Summary
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