我正在使用3D C# .Net图形的Wpf平台上工作。
以下是代码流程：
1）我从kinect获取深度数据并将其赋予一个计算3d点的函数。
private void display3DView（）
{
while(loop_run)
{
using ( DepthImageFrame depthFrame = sensor.DepthStream.OpenNextFrame(1000))
{
if (depthFrame == null) continue;
Point3DCollection PointCloud ;
depthFrame.CopyDepthImagePixelDataTo(this.depthImagePixels);
float[,] ImageArray = new float[320, 240];
short [ ,] depth = new short[240,320];
for (int i = 0; i < 240; i++)
{
for (int j = 0; j <320; j++)
{
depth[i,j]= depthImagePixels[j+i *320].Depth;
ImageArray[i,j] =(float)depth[i,j]/(float)1000;
}
}
PointCloud =Calculate_PointCloud(ImageArray);
viewModel(PointCloud);
}
}
}</i>
2）我用相机参数和Kinect相机的深度数据计算了3D点
私有Point3DCollection Calculate_PointCloud（float [，] ImageArray） {
Point3DCollection PointCloud = new Point3DCollection();
float x_coodinate;``
float y_coordinate;
float z_coordinate;
float thresholdvalue = 2.0f;
for (int i = 0; i < 239; ++i)
{
for (int j = 0; j < 319; ++j)
{
if (Math.Abs(ImageArray[i, j] - ImageArray[i, j + 1]) < thresholdvalue && Math.Abs(ImageArray[i, j] - ImageArray[i + 1, j]) < thresholdvalue && Math.Abs(ImageArray[i, j + 1] - ImageArray[i + 1, j]) < thresholdvalue)
{
z_coordinate = ImageArray[i, j];
x_coodinate = ((j - this.PrincipalPointX) * z_coordinate) / FocalLengthX;
y_coordinate = ((i - this.PrincipalPointY) * z_coordinate) / FocalLengthY;
Point3D point1 = new Point3D(x_coodinate, y_coordinate, z_coordinate);
PointCloud.Add(point1);
z_coordinate = ImageArray[i, j + 1];
x_coodinate = (((j + 1) - this.PrincipalPointX) * z_coordinate) / FocalLengthX;
y_coordinate = ((i - this.PrincipalPointY) * z_coordinate) / FocalLengthY;
Point3D point2 = new Point3D(x_coodinate, y_coordinate, z_coordinate);
PointCloud.Add(point2);
z_coordinate = ImageArray[i + 1, j];
x_coodinate = ((j - this.PrincipalPointX) * z_coordinate) / FocalLengthX;
y_coordinate = (((i + 1) - this.PrincipalPointY) * z_coordinate) / FocalLengthY;
Point3D point3 = new Point3D(x_coodinate, y_coordinate, z_coordinate);
PointCloud.Add(point3);
}
}
}
return PointCloud;
}</i>
3）在这里，我转换为具有每个3D点的正常信息的三角形集合，并将这些三角形赋予3D网格对象并使用viewport3D控件渲染3d网格对象
private void viewModel（Point3DCollection points）
{
DirectionalLight DirLight1 = new DirectionalLight();
DirLight1.Color = Colors.White;
DirLight1.Direction = new Vector3D(1, 1, 1);
PerspectiveCamera Camera1 = new PerspectiveCamera();
Camera1.FarPlaneDistance = 8000;
Camera1.NearPlaneDistance = 100;
Camera1.FieldOfView = 10;
Camera1.Position = new Point3D(0, 0, 1);
Camera1.LookDirection = new Vector3D(-1, -1, -1);
Camera1.UpDirection = new Vector3D(0, 1, 0);
bool combinedvertices = true;
TriangleModel Triatomesh = new TriangleModel();
MeshGeometry3D tmesh = new MeshGeometry3D();
GeometryModel3D msheet = new GeometryModel3D();
Model3DGroup modelGroup = new Model3DGroup();
ModelVisual3D modelsVisual = new ModelVisual3D();
Viewport3D myViewport = new Viewport3D();
for(int i =0; i<points.Count; i+=3)
{
Triatomesh.addTriangleToMesh(points[i],points[i + 1], points[i + 2], tmesh, combinedvertices);
}
msheet.Geometry = tmesh;
msheet.Material = new DiffuseMaterial(new SolidColorBrush(Colors.White));
modelGroup.Children.Add(msheet);
modelGroup.Children.Add(DirLight1);
modelsVisual.Content = modelGroup;
myViewport.IsHitTestVisible = false;
myViewport.Camera = Camera1;
myViewport.Children.Add(modelsVisual);
canvas1.Children.Add(myViewport);
myViewport.Height = canvas1.Height;
myViewport.Width = canvas1.Width;
Canvas.SetTop(myViewport, 0);
Canvas.SetLeft(myViewport, 0);
} </i>
4）这是一个函数，它通过计算每个3D点的法线来获取三个3D点并将三维网格物体添加为三角形
public void addTriangleToMesh(Point3D p0, Point3D p1, Point3D p2,
MeshGeometry3D mesh, bool combine_vertices)
{
Vector3D normal = CalculateNormal(p0, p1, p2);
if (combine_vertices)
{
addPointCombined(p0, mesh, normal);
addPointCombined(p1, mesh, normal);
addPointCombined(p2, mesh, normal);
}
else
{
mesh.Positions.Add(p0);
mesh.Positions.Add(p1);
mesh.Positions.Add(p2);
//mesh.TriangleIndices.Add(mesh.TriangleIndices.Count);
// mesh.TriangleIndices.Add(mesh.TriangleIndices.Count);
// mesh.TriangleIndices.Add(mesh.TriangleIndices.Count);
mesh.Normals.Add(normal);
mesh.Normals.Add(normal);
mesh.Normals.Add(normal);
}
}
public Vector3D CalculateNormal(Point3D P0, Point3D P1, Point3D P2) //static
{
Vector3D v0 = new Vector3D(P1.X - P0.X, P1.Y - P0.Y, P1.Z - P0.Z);
Vector3D v1 = new Vector3D(P2.X - P1.X, P2.Y - P1.Y, P2.Z - P1.Z);
return Vector3D.CrossProduct(v0, v1);
}
public void addPointCombined(Point3D point, MeshGeometry3D mesh, Vector3D normal)
{
bool found = false;
int i = 0;
foreach (Point3D p in mesh.Positions)
{
if (p.Equals(point))
{
found = true;
mesh.TriangleIndices.Add(i);
mesh.Positions.Add(point);
mesh.Normals.Add(normal);
break;
}
i++;
}
if (!found)
{
mesh.Positions.Add(point);
mesh.TriangleIndices.Add(mesh.TriangleIndices.Count);
mesh.Normals.Add(normal);
}
}
5）这是我的XAML代码
<Window x:Class="PointCloud3DView.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="PointCloud" Height="653" Width="993" Background="Black" Loaded="Window_Loaded">
<Grid Height="1130" Width="1626">
<Canvas Height="611" HorizontalAlignment="Left" Name="canvas1" VerticalAlignment="Top"
宽度=“967”背景=“黑色”/＆gt;
</Grid>
问题是我无法在Wpf Screen中显示3D模型。请问任何人都可以浏览整个代码吗？并让我明白我哪里出错了？并建议我纠正。 提前致谢
答案 0 :(得分：1)
我已经在几周内尝试了WPF 3D，并且学到了一些难以理解的东西:) 我现在没有时间检查并尝试整个代码。但是我会尝试三件事：
我不确定相机的方向。它在（0,1,0）， 使用矢量（-1，-1，-1）查找，这意味着它专注于中心 点（-1,0，-1）。这有点奇怪......尝试定位相机 进一步（取决于您的模型的规模），如（0,10,0）或甚至 进一步将其集中在（0,0,0）或你的中心点的任何地方 模特是：
Camera1.Position = new Point3D（0,10,0）;
Camera1.LookDirection = new Point3D（0,0,0） - Camera1.Position;
同时删除定向灯（因为它使用法线，如果它们出错则不会显示任何内容）并尝试使用环境光。和你的 定向闪电与您的外观正好相反 方向（-1，-1，-1）和（1,1,1）。
尝试在三角形索引中交换点的顺序（WPF只渲染网格的一侧，因此模型可能在那里但在内部/外部） - 而不是0,1,2尝试0,2,1;
如果没有任何帮助，我会在回家后尝试您的代码。
/ 稍后编辑 / 在简单的三角形上编写你的代码并根据我的提示重写它并且它有效。如何清理代码有一些注释和两个提示：）
private void viewModel(Point3DCollection points)
{
DirectionalLight DirLight1 = new DirectionalLight();
DirLight1.Color = Colors.White;
DirLight1.Direction = new Vector3D(1, 1, 1);
PerspectiveCamera Camera1 = new PerspectiveCamera();
Camera1.FarPlaneDistance = 8000;
//Camera1.NearPlaneDistance = 100; //close object will not be displayed with this option
Camera1.FieldOfView = 10;
//Camera1.Position = new Point3D(0, 0, 1);
//Camera1.LookDirection = new Vector3D(-1, -1, -1);
Camera1.Position = new Point3D(0, 0, 10);
Camera1.LookDirection = new Point3D(0, 0, 0) - Camera1.Position; //focus camera on real center of your model (0,0,0) in this case
Camera1.UpDirection = new Vector3D(0, 1, 0);
//you can use constructor to create Camera instead of assigning its properties like:
//PerspectiveCamera Camera1 = new PerspectiveCamera(new Point3D(0,0,10), new Vector3D(0,0,-1), new Vector3D(0,1,0), 10);
bool combinedvertices = true;
TriangleModel Triatomesh = new TriangleModel();
MeshGeometry3D tmesh = new MeshGeometry3D();
GeometryModel3D msheet = new GeometryModel3D();
Model3DGroup modelGroup = new Model3DGroup();
ModelVisual3D modelsVisual = new ModelVisual3D();
Viewport3D myViewport = new Viewport3D();
for (int i = 0; i < points.Count; i += 3)
{
Triatomesh.addTriangleToMesh(points[i + 2], points[i + 1], points[i], tmesh, combinedvertices);
//I did swap order of vertexes you may try both options with your model
}
msheet.Geometry = tmesh;
msheet.Material = new DiffuseMaterial(new SolidColorBrush(Colors.White));
//you can use constructor to create GeometryModel3D instead of assigning its properties like:
//msheet = new GeometryModel3D(tmesh, new DiffuseMaterial(new SolidColorBrush(Colors.White)));
modelGroup.Children.Add(msheet);
//use AMbientLIght instead of directional
modelGroup.Children.Add(new AmbientLight(Colors.White));
modelsVisual.Content = modelGroup;
myViewport.IsHitTestVisible = false;
myViewport.Camera = Camera1;
myViewport.Children.Add(modelsVisual);
canvas1.Children.Add(myViewport);
myViewport.Height = canvas1.Height;
myViewport.Width = canvas1.Width;
Canvas.SetTop(myViewport, 0);
Canvas.SetLeft(myViewport, 0);
}
我使用Points3DCollection作为参数（而不是Kinect输入）：
Point3DCollection points = new Point3DCollection();
points.Add(new Point3D(0.5, 0, 0.5));
points.Add(new Point3D(0.5, -0.5, -0.5));
points.Add(new Point3D(-0.5, -0.1, -0.5));
viewModel(points);