xBIM Viewer：从画布创建屏幕截图

要创建xBIM Viewer画布的屏幕截图，可以使用xBIM Toolkit提供的功能。下面是一个示例代码，展示了如何使用xBIM Viewer创建屏幕截图：

using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Windows.Forms;
using Xbim.Common;
using Xbim.Ifc;
using Xbim.ModelGeometry.Scene;

public class XbimViewerScreenshot
{
    private IfcStore model;
    private Xbim3DModelContext modelContext;
    private XbimVisualStyle style;
    private XbimModelFactors factors;

    public XbimViewerScreenshot(string ifcFilePath)
    {
        model = IfcStore.Open(ifcFilePath);
        modelContext = new Xbim3DModelContext(model);
        modelContext.CreateContext();

        style = new XbimVisualStyle();
        factors = new XbimModelFactors();
    }

    public void CaptureScreenshot(string outputFilePath)
    {
        var viewer = new XbimXplorerControl();

        viewer.DefaultVisualStyle = style;
        viewer.SetModel(model, modelContext);
        viewer.FitView();

        var screenshot = viewer.CaptureScreenshot();

        screenshot.Save(outputFilePath, ImageFormat.Png);

        viewer.Close();
    }

    public void Dispose()
    {
        model?.Dispose();
    }
}

使用方法：

var screenshotGenerator = new XbimViewerScreenshot("path_to_ifc_file.ifc");
screenshotGenerator.CaptureScreenshot("output_path.png");
screenshotGenerator.Dispose();

请确保您已正确安装了xBIM Toolkit和相关的依赖项。此示例使用了Windows Forms中的XbimXplorerControl控件来显示模型。您可以根据自己的需求进行调整，例如使用更适合您的UI框架或控件来显示和操作模型。