MaterialConverterPrism Extension是为Autodesk Forge Viewer创建的一个扩展，其主要作用是将特定格式的材质转换为可以在Viewer中渲染的格式。它主要通过解析不支持在Forge Viewer中渲染的材质属性，创建一种等效的材质。以下是一个使用MaterialConverterPrism Extension的代码示例：

const viewer = new Autodesk.Viewing.GuiViewer3D(container);
const options = {
  env: 'AutodeskProduction',
  api: 'derivativeV2',
  accessToken: 'ACCESS_TOKEN_HERE'
};
Autodesk.Viewing.Initializer(options, () => {
  viewer.start();
  const documentId = 'URN_HERE';
  Autodesk.Viewing.Document.load(documentId, (doc) => {
    const viewables = doc.getRoot().getDefaultGeometry();
    viewer.setDocument(doc, viewables);
    viewer.addEventListener(Autodesk.Viewing.GEOMETRY_LOADED_EVENT, () => {
      const materialConverter = viewer.impl.matman()._materialCache._materialsByModelId.default.Extension.MaterialConverter;
      const convertedMaterial = materialConverter.convert({
        type: 'StdMaterial',
        diffuse: 16777215,
        specular: 16777215,
        opacity: 0.5
      });
      console.log(convertedMaterial); // outputs the converted material
    });
  });
});