# PerInstanceColorAppearance

#### new Cesium.PerInstanceColorAppearance(options)
Scene/PerInstanceColorAppearance.js 85

  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.

  Name | Type | Description
  --- | --- | ---
  `options` | Object | optional Object with the following properties:
  Name | Type | Default | Description
  --- | --- | --- | ---
  `flat` | Boolean | `false` | optional When `true`, flat shading is used in the fragment shader, which means lighting is not taking into account.
  `faceForward` | Boolean | `!options.closed` | optional 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 | `true` | optional When `true`, the geometry is expected to appear translucent so `PerInstanceColorAppearance#renderState` has alpha blending enabled.
  `closed` | Boolean | `false` | optional 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.

  ##### 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()
      });

  ##### Demo:

  - Cesium Sandcastle Per Instance Color Appearance Demo

### Members

#### static constantCesium.PerInstanceColorAppearance.FLAT_VERTEX_FORMAT : VertexFormat
Scene/PerInstanceColorAppearance.js 266

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

#### static constantCesium.PerInstanceColorAppearance.VERTEX_FORMAT : VertexFormat
Scene/PerInstanceColorAppearance.js 255

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

#### readonlyclosed : Boolean
Scene/PerInstanceColorAppearance.js 187

  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.
  Default Value: `false`

#### readonlyfaceForward : Boolean
Scene/PerInstanceColorAppearance.js 239

  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`.
  Default Value: `true`

#### readonlyflat : Boolean
Scene/PerInstanceColorAppearance.js 220

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

#### readonlyfragmentShaderSource : String
Scene/PerInstanceColorAppearance.js 150

  The GLSL source code for the fragment shader.

#### material : Material
Scene/PerInstanceColorAppearance.js 103

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

#### readonlyrenderState : Object
Scene/PerInstanceColorAppearance.js 169

  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`.

#### translucent : Boolean
Scene/PerInstanceColorAppearance.js 113

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

#### readonlyvertexFormat : VertexFormat
Scene/PerInstanceColorAppearance.js 203

  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.

#### readonlyvertexShaderSource : String
Scene/PerInstanceColorAppearance.js 136

  The GLSL source code for the vertex shader.

### Methods

#### getFragmentShaderSource() → String
Scene/PerInstanceColorAppearance.js 277

  Procedurally creates the full GLSL fragment shader source. For `PerInstanceColorAppearance`, this is derived from `PerInstanceColorAppearance#fragmentShaderSource`, `PerInstanceColorAppearance#flat`, and `PerInstanceColorAppearance#faceForward`.

  ##### Returns:

  The full GLSL fragment shader source.

#### getRenderState() → Object
Scene/PerInstanceColorAppearance.js 297

  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.

  ##### Returns:

  The render state.

#### isTranslucent() → Boolean
Scene/PerInstanceColorAppearance.js 286

  Determines if the geometry is translucent based on `PerInstanceColorAppearance#translucent`.

  ##### Returns:

  `true` if the appearance is translucent.