Full list
VRML Interactive Tutorial
Introduction
VRML File Structure
Drawing: Shape node
Geometry Nodes:
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Box
Sphere Cone Cylinder PointSet IndexedLineSet IndexedFaceSet Extrusion ElevationGrid Example: Chessboard Text FontStyle |
| Material
Textures
Texture Transform |
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Directional Light
Point Light Spot Light |
Hierarchical Node Structures
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Group
Transform Collision Anchor Billboard Switch |
Defining and Instancing Nodes
Defining Levels of Detail
Events in VRML
|
Creating Paths between events:
ROUTE
Generating Events based on Timers or User Actions
|
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Color
Coordinate Normal Orientation Position Scalar Example |
|
Sound
AudioClip |
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Who Am I: NavigationInfo
Where Am I: ViewPoint |
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Background
Fog |
| WorldInfo |
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Coordinate
Color Normal |
ColorInterpolator
The ColorInterpolator node is an interpolator which takes a list of RGB values in the field keyValue.
For a list of the events of this node see interpolator.
Syntax:
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Example:
-
Using this interpolator to set an initial red color, and gradually change it to blue.
ColorInterpolator {- key [0 1 ]
- keyValue[1 0 0, 0 0 1 ]
Using this interpolator to set an initial red color, change it to blue and afterwards change it to green.
ColorInterpolator {- key [0 0.5 1 ]
- keyValue[1 0 0, 0 0 1, 0 1 0 ]
A complete example is now presented. A Shape is drawn with a default black diffuse color. The ColorInterpolator will set an initial red diffuseColor, and gradually change it to blue. After that the Shape will remain with a blue diffuse color.
First one needs the to define a Group with a Shape, a TimeSensor, and a ColorInterpolator.
#VRML V2.0 utf8
Group {- children [
- Shape {
- appearance Appearance {
- material DEF mat Material { diffuseColor 0 0 0 }
- }
- geometry Sphere {}
- }
- DEF ci ColorInterpolator {
- key [ 0 1 ]
- keyValue [ 1 0 0, 0 0 1]
- }
- DEF ts TimeSensor {
- cycleInterval 2
- loop FALSE
- }
- ]
Now the only thing which is missing is routing the events.
We need to get the eventOut fraction_changed generated by the TimeSensor. This event outputs a value between 0 and 1. We can use this value to set a key for the ColorInterpolator by routing the fraction_changed eventOut from the TimeSensor to the set_fraction eventIn from the ColorInterpolator.
A new fraction being set in an interpolator causes the keyValue to be changed. As a consequence the interpolator will generate the fraction_changed eventOut. Because the interpolator used is a ColorInterpolator, this event outputs a RGB value.
Finally we use this eventOut to set a color in the Material node. Note that the color that we want to change is the diffuse color. Because the diffuseColor is an exposed field of the Material node we can use the eventIn set_diffuseColor to change the color. To do this we route the fraction_changed eventOut of the ColorInterpolator to the set_diffuseColor eventIn of the Material node.
The ROUTE statements to do this are:
- ROUTE ts.fraction_changed TO ci.set_fraction
- ROUTE ci.value_changed TO mat.set_diffuseColor
