Class: PerInstanceColorAppearance

PerInstanceColorAppearance

new PerInstanceColorAppearance(optionsopt)

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.
Parameters:
Name Type Attributes Description
options Object <optional>
 Object with the following properties:
Properties
Name Type Attributes Default Description
flat Boolean <optional>
 false When true, flat shading is used in the fragment shader, which means lighting is not taking into account.
faceForward Boolean <optional>
 !options.closed 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.
translucent Boolean <optional>
 true When true, the geometry is expected to appear translucent so PerInstanceColorAppearance#renderState has alpha blending enabled.
closed Boolean <optional>
 false When true, the geometry is expected to be closed so PerInstanceColorAppearance#renderState has backface culling enabled.
vertexShaderSource String <optional>
 Optional GLSL vertex shader source to override the default vertex shader.
fragmentShaderSource String <optional>
 Optional GLSL fragment shader source to override the default fragment shader.
renderState RenderState <optional>
 Optional render state to override the default render state.
Source:
Example
// A solid white line segment
var 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
var instance = new Cesium.GeometryInstance({
  geometry : new Cesium.RectangleGeometry({
    rectangle : Cesium.Rectangle.fromDegrees(0.0, 20.0, 10.0, 30.0)
  }),
  attributes : {
    color : new Cesium.Color(1.0, 0.0, 0.0, 0.5)
  }
});

var anotherInstance = new Cesium.GeometryInstance({
  geometry : new Cesium.RectangleGeometry({
    rectangle : Cesium.Rectangle.fromDegrees(0.0, 40.0, 10.0, 50.0)
  }),
  attributes : {
    color : new Cesium.Color(0.0, 0.0, 1.0, 0.5)
  }
});

var rectanglePrimitive = new Cesium.Primitive({
  geometryInstances : [instance, anotherInstance],
  appearance : new Cesium.PerInstanceColorAppearance()
});

Members

(static, constant) FLAT_VERTEX_FORMAT :VertexFormat

The VertexFormat that all PerInstanceColorAppearance instances are compatible with when PerInstanceColorAppearance#flat is false. This requires only a position attribute.
Type:
Source:

(static, constant) VERTEX_FORMAT :VertexFormat

The VertexFormat that all PerInstanceColorAppearance instances are compatible with. This requires only position and st attributes.
Type:
Source:

(readonly) closed :Boolean

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.
Type:
  • Boolean
Default Value:
  • false
Source:

(readonly) faceForward :Boolean

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.
Type:
  • Boolean
Default Value:
  • true
Source:

(readonly) flat :Boolean

When true, flat shading is used in the fragment shader, which means lighting is not taking into account.
Type:
  • Boolean
Default Value:
  • false
Source:

(readonly) fragmentShaderSource :String

The GLSL source code for the fragment shader.
Type:
  • String
Source:

material :Material

This property is part of the Appearance interface, but is not used by PerInstanceColorAppearance since a fully custom fragment shader is used.
Type:
Default Value:
  • undefined
Source:

(readonly) renderState :Object

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.

Type:
  • Object
Source:

translucent :Boolean

When true, the geometry is expected to appear translucent so PerInstanceColorAppearance#renderState has alpha blending enabled.
Type:
  • Boolean
Default Value:
  • true
Source:

(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.
Type:
Source:

(readonly) vertexShaderSource :String

The GLSL source code for the vertex shader.
Type:
  • String
Source:

Methods

getFragmentShaderSource() → {String}

Procedurally creates the full GLSL fragment shader source. For PerInstanceColorAppearance, this is derived from PerInstanceColorAppearance#fragmentShaderSource, PerInstanceColorAppearance#flat, and PerInstanceColorAppearance#faceForward.
Source:
Returns:
The full GLSL fragment shader source.
Type
String

getRenderState() → {Object}

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.
Source:
Returns:
The render state.
Type
Object

isTranslucent() → {Boolean}

Determines if the geometry is translucent based on PerInstanceColorAppearance#translucent.
Source:
Returns:
true if the appearance is translucent.
Type
Boolean