我试图使用ArcSegment将模型的一部分渲染为半圆。我的代码使用了许多基于2D路径的对象。除了使用ArcSegment的模块外，所有工作都正常。例如，使用LineSegment的类似模块可以正常工作。
我可以看到我的ArcSegment的基本几何图形是正确的，因为Fill属性通过填充预期半圆内的区域来使弧可见。
我没有使用XAML。所有形状都是使用C＃/ WPF函数构建的。
以下是使用WPF Path对象渲染所有Geometry对象的代码：
// builder constructs a collection of Geometry objects and returns the in a GeometryGroup via ToGeometry()
GeometryGroup model2D = builder.ToGeometry();
model2D.Transform = BuildLocalTransform2D(visualModel);
var visual2D = new System.Windows.Shapes.Path();
if (typeof(Foundation.Visualisation.Elements2D.ShapeElement).IsAssignableFrom(visualModel.GetType()))
visual2D.Fill = ((Foundation.Visualisation.Elements2D.ShapeElement)visualModel).ShapeStyle.BackgroundBrush;
else
// ArcSegment and LineSegment based geometries always follow this path
// was using transparent but needed to add a color to make ArcSegment based Path visible
// the assignment to Stroke below does not work (line remains transparent) when model2D contains a PathGeometry that contains one ArcSegment
// I can see that the arc has the correct shape when the fill is not transparent
//visual2D.Fill = Brushes.Transparent;
visual2D.Fill = Brushes.Cyan;
// debug shows StrokeThickness is always 2
visual2D.StrokeThickness = ((PathElement)visualModel).LineStyle.LineThickness;
// debug shows that Stroke is always Brushes.Black
visual2D.Stroke = ((PathElement)visualModel).LineStyle.LineBrush;
visual2D.StrokeStartLineCap = PenLineCap.Round;
visual2D.StrokeEndLineCap = PenLineCap.Round;
visual2D.StrokeLineJoin = PenLineJoin.Round;
visual2D.Data = model2D;
WpfVisual2DProxy node = new WpfVisual2DProxy(visual2D, visualModel);
visualModel.AddProxy(node);
// the following adds the visual to an ItemsControl using a Canvas based template:
// this.ItemsPanel = new ItemsPanelTemplate(new FrameworkElementFactory(typeof(Canvas)));
((VisualContainer)((WpfVisual2DProxy)parentNode).Visual2D).AddChild(visual2D);
以下是我用来创建ArcSegment的代码：
public void AddArc(ModelPoint2D arcStart, ModelPoint2D arcEnd, double ellipseFactor, double degrees, bool isLarge, SweepDirection sweepDirection, LineVisualStyle lineStyle)
{
double radius = ellipseFactor * arcStart.Distance(arcEnd) / 2.0;
List<ArcSegment> list = new List<ArcSegment>(2);
Point start = converter.ToPoint2D(arcStart);
list.Add(new ArcSegment(converter.ToPoint2D(arcEnd), new Size(radius, radius), Extrusion.DegreesToRadians(degrees), isLarge, SweepDirection.Clockwise, false));
var pathFigure = new PathFigure(start, list, false);
var pfList = new List<PathFigure>(1);
pfList.Add(pathFigure);
group.Children.Add(new PathGeometry(pfList));
}
此处生成的几何体始终具有透明笔划，但可以使用“填充”属性使圆弧可见。
下面是我用来创建半圆形等效半径的代码：
public void AddPath(IList<ModelPoint2D> Points, LineVisualStyle lineStyle)
{
List<LineSegment> list = new List<LineSegment>(Points.Count);
Point start = converter.ToPoint2D(Points[0]);
for (int i = 1; i < Points.Count; i++)
{
list.Add(new LineSegment(converter.ToPoint2D(Points[i]), true));
}
var pathFigure = new PathFigure(start, list, false);
var pfList = new List<PathFigure>(1);
pfList.Add(pathFigure);
group.Children.Add(new PathGeometry(pfList));
}
使用LineSegment的代码会产生一个响应笔画和填充设置的几何。
结果渲染如下所示：
The Semicircle at the top has Fill visible but not Stroke
我尝试了很多组合，包括将PathGeometry直接添加到Path.Data而不是包装在GeometryGroup中。
非常感谢任何建议/协助。
请求的VisualModel代码如下：
public abstract class VisualModel
{
/// <summary>
/// Recursive hierarchy of VisualModel objects that describe the visual structure of an entity for a specific ViewportType.
/// The top level of the hierarchy is owned by EntityViews via a ViewportTypeVisualModel entry
/// </summary>
/// <param name="id">An optional model component identifier - useful for debug</param>
public VisualModel(string id)
{
domainBindings = null;
proxies = null;
Id = id;
ParentVisualModel = null;
LocalTransforms = null;
IsStatic = true;
}
public bool HasDomainBindings
{
get
{
if (domainBindings == null)
return false;
return domainBindings.Count > 0;
}
}
public bool HasProxies
{
get
{
if (proxies == null)
return false;
return proxies.Count > 0;
}
}
public string Id { get; private set; }
/// <summary>
/// Static objects are not affected by transforms that change after the render is constructed.
/// Non-Static (Dynamic) objects have transforms that may be changed by the application after the render is constructed
/// Dynamic objects have attached event handlers that adjust the transforms in response to application events
/// </summary>
public bool IsStatic { get; private set; }
public List<TransformBase> LocalTransforms { get; private set; }
public VisualModel ParentVisualModel { get; internal set; }
public void AddDomainBinding(BindingBase binding)
{
DomainBindings.Add(binding);
}
public void AddLocalTransform(TransformBase transform)
{
if (LocalTransforms == null)
LocalTransforms = new List<TransformBase>(4);
LocalTransforms.Add(transform);
if (transform.IsDynamic)
IsStatic = false;
}
public void AddProxy(VisualProxy visualProxy)
{
Proxies.Add(visualProxy);
}
protected List<BindingBase> DomainBindings
{
get
{
if (domainBindings == null)
domainBindings = new List<BindingBase>();
return domainBindings;
}
}
protected List<VisualProxy> Proxies
{
get
{
if (proxies == null)
proxies = new List<VisualProxy>();
return proxies;
}
}
public virtual void UnbindAll()
{
if (domainBindings == null)
return;
foreach (BindingBase binding in this.DomainBindings)
binding.UnBind();
}
private List<BindingBase> domainBindings;
private List<VisualProxy> proxies;
}
请注意，VisualModel表示图形/渲染技术不可知模型容器。它包含的VisualProxy对象是特定于技术的图形对象的基类。在这种情况下，WpfVisual2DProxy对象包装包含我的WPF可渲染表示的WPF UIElement对象。
以下是VisualProxy：
public abstract class VisualProxy
{
public VisualModel.VisualModel VisualModel { get; private set; }
public VisualProxy Parent { get; private set; }
public VisualProxy(VisualModel.VisualModel visualModel)
{
VisualModel = visualModel;
Parent = null;
}
public VisualProxy(VisualModel.VisualModel visualModel, VisualProxy parent)
{
VisualModel = visualModel;
Parent = parent;
}
}
以下是WpfVisual2DProxy：
public class WpfVisual2DProxy : VisualProxy
{
public UIElement Visual2D { get; private set; }
public WpfVisual2DProxy(UIElement visual2D, VisualModel visualModel) : base(visualModel)
{
Visual2D = visual2D;
}
public WpfVisual2DProxy(UIElement visual2D, VisualModel visualModel, WpfVisual2DProxy parent) : base(visualModel, parent)
{
Visual2D = visual2D;
}
}
答案 0 :(得分：0)
非常感谢所有想到我的问题的人。
克莱门斯是对的。我的ArcSegment上没有将isStroked设置为true。
令人尴尬的简单。
谢谢