An appearance for
GeometryInstance instances with color attributes.
This allows several geometry instances, each with a different color, to
be drawn with the same Primitive as shown in the second example below.
| 参数名称 | 类型 | 描述信息 | ||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
options |
object |
可选
Object with the following properties:
|
使用示例:
// A solid white line segment
const primitive = new Cesium.Primitive({
geometryInstances : new Cesium.GeometryInstance({
geometry : new Cesium.SimplePolylineGeometry({
positions : Cesium.Cartesian3.fromDegreesArray([
0.0, 0.0,
5.0, 0.0
])
}),
attributes : {
color : Cesium.ColorGeometryInstanceAttribute.fromColor(new Cesium.Color(1.0, 1.0, 1.0, 1.0))
}
}),
appearance : new Cesium.PerInstanceColorAppearance({
flat : true,
translucent : false
})
});
// Two rectangles in a primitive, each with a different color
const instance = new Cesium.GeometryInstance({
geometry : new Cesium.RectangleGeometry({
rectangle : Cesium.Rectangle.fromDegrees(0.0, 20.0, 10.0, 30.0)
}),
attributes : {
color : new Cesium.ColorGeometryInstanceAttribute(1.0, 0.0, 0.0, 0.5)
}
});
const anotherInstance = new Cesium.GeometryInstance({
geometry : new Cesium.RectangleGeometry({
rectangle : Cesium.Rectangle.fromDegrees(0.0, 40.0, 10.0, 50.0)
}),
attributes : {
color : new Cesium.ColorGeometryInstanceAttribute(0.0, 0.0, 1.0, 0.5)
}
});
const rectanglePrimitive = new Cesium.Primitive({
geometryInstances : [instance, anotherInstance],
appearance : new Cesium.PerInstanceColorAppearance()
});成员(属性)
static constant Cesium.PerInstanceColorAppearance.FLAT_VERTEX_FORMAT : VertexFormat
The
VertexFormat that all PerInstanceColorAppearance instances
are compatible with when PerInstanceColorAppearance#flat is true.
This requires only a position attribute.
static constant Cesium.PerInstanceColorAppearance.VERTEX_FORMAT : VertexFormat
The
VertexFormat that all PerInstanceColorAppearance instances
are compatible with. This requires only position and normal
attributes.
When
true, the geometry is expected to be closed so
PerInstanceColorAppearance#renderState has backface culling enabled.
If the viewer enters the geometry, it will not be visible.
-
默认值:
false
When
true, the fragment shader flips the surface normal
as needed to ensure that the normal faces the viewer to avoid
dark spots. This is useful when both sides of a geometry should be
shaded like WallGeometry.
-
默认值:
true
When
true, flat shading is used in the fragment shader,
which means lighting is not taking into account.
-
默认值:
false
The GLSL source code for the fragment shader.
This property is part of the
Appearance interface, but is not
used by PerInstanceColorAppearance since a fully custom fragment shader is used.
-
默认值:
undefined
The WebGL fixed-function state to use when rendering the geometry.
The render state can be explicitly defined when constructing a PerInstanceColorAppearance
instance, or it is set implicitly via PerInstanceColorAppearance#translucent
and PerInstanceColorAppearance#closed.
When
true, the geometry is expected to appear translucent so
PerInstanceColorAppearance#renderState has alpha blending enabled.
-
默认值:
true
readonly vertexFormat : VertexFormat
The
VertexFormat that this appearance instance is compatible with.
A geometry can have more vertex attributes and still be compatible - at a
potential performance cost - but it can't have less.
The GLSL source code for the vertex shader.
方法
Procedurally creates the full GLSL fragment shader source. For
PerInstanceColorAppearance,
this is derived from PerInstanceColorAppearance#fragmentShaderSource, PerInstanceColorAppearance#flat,
and PerInstanceColorAppearance#faceForward.
返回值:
The full GLSL fragment shader source.
Creates a render state. This is not the final render state instance; instead,
it can contain a subset of render state properties identical to the render state
created in the context.
返回值:
The render state.
Determines if the geometry is translucent based on
PerInstanceColorAppearance#translucent.
返回值:
true if the appearance is translucent.