CesiumJS version up to 1.89

    <parent>

        <artifactId>cesiumjs4gwt</artifactId>

        <groupId>org.cesiumjs</groupId>

        <version>1.88.0</version>

        <version>1.89.0</version>

    </parent>

    <name>CesiumJS GWT Wrapper</name>

  vertexShaderText: `

    // IMPORTANT: the function signature must use these parameter names. This

    // makes it easier for the runtime to generate the shader and make optimizations.

    void vertexMain(VertexInput vsInput, inout vec3 positionMC) {

        // code goes here. e.g. for a no-op:

        return positionMC;

    void vertexMain(VertexInput vsInput, inout czm_modelVertexOutput vsOutput) {

        // code goes here. An empty body is a no-op.

    }

  `,

  // Custom fragment shader.

  },

  // User assigns the varying in the vertex shader

  vertexShaderText: `

    void vertexMain(VertexInput vsInput, inout vec3 positionMC) {

    void vertexMain(VertexInput vsInput, inout czm_modelVertexOutput vsOutput) {

        float positiveX = step(0.0, positionMC.x);

        v_selectedColor = mix(

            vsInput.attributes.color_0,

            vsInput.attributes.color_1,

            positionMC.x

            vsOutput.positionMC.x

        );

        return positionMC;

    }

  `,

  // User uses the varying in the fragment shader

letters and underscores. For example, an attribute called `_SURFACE_TEMPERATURE`

in the model would become `fsInput.attributes.surface_temperature` in the shader.

## `czm_modelVertexOutput` struct

This struct is built-in, see the [documentation comment](../../../Shaders/Builtin/Structs/modelVertexOutput.glsl).

This struct contains the output of the custom vertex shader. This includes:

- `positionMC` - The vertex position in model space coordinates. This struct

  field can be used e.g. to perturb or animate vertices. It is initialized to

  `vsInput.attributes.positionMC`. The custom shader may modify this, and the

  result is used to compute `gl_Position`.

- `pointSize` - corresponds to `gl_PointSize`. This is only applied for models

  rendered as `gl.POINTS`, and ignored otherwise.

> **Implementation Note**: `positionMC` does not modify the primitive's bounding

> sphere. If vertices are moved outside the bounding sphere, the primitive may

> be unintentionally culled depending on the view frustum.

## `czm_modelMaterial` struct

This one is a built-in, see the [documentation comment](../../../Shaders/Builtin/Structs/modelMaterial.glsl). This is similar to `czm_material` from the old Fabric system, but slightly different fields as this one supports PBR lighting.

This struct is a built-in, see the [documentation comment](../../../Shaders/Builtin/Structs/modelMaterial.glsl). This is similar to `czm_material` from the old Fabric system, but slightly different fields as this one supports PBR lighting.

This struct serves as the basic input/output of the fragment shader pipeline stages. For example: