How to render layers

GroupDocs.Viewer renders all layers of the CAD drawing by default. To render specific layers you can set the layers that you want to render by adding them into the setLayers() property of CadOptions (method getCadOptions() of HtmlViewOptionsJpgViewOptionsPngViewOptions or PdfViewOptions class). 

The following code sample shows how to render a specific layer of a CAD drawing.

    try (Viewer viewer = new Viewer("sample.dwg")) {
        HtmlViewOptions viewOptions = HtmlViewOptions.forEmbeddedResources();
        viewOptions.getCadOptions().setLayers(Arrays.asList(new Layer("TRIANGLE"), new Layer("QUADRANT")));