3D 应用程序未渲染场景

Question

I looked through the Microsoft page on 3D graphics and even tried to draw their example cone, but nothing's showing up on the screen. I've looked over the code several times but can't seem to find what's wrong...

XAML code:

<Window x:Class="WpfApp2.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp2"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <Grid.Resources>
            <MeshGeometry3D x:Key="meshPyramid" Positions="0 75 0  -50 0 50  50 0 50  50 0 -50" TriangleIndices="0 1 2  0 2 3"></MeshGeometry3D>
            <MeshGeometry3D x:Key="desertFloor" Positions="-9999,0,-9999  9999,0,-9999  9999,0,9999  -9999,0,9999" TextureCoordinates="0,0  1,0  1,1  0,1" TriangleIndices="0 1 3  1 2 3"></MeshGeometry3D>
            <DiffuseMaterial x:Key="matFont" Brush="Black">
            </DiffuseMaterial>
            <DiffuseMaterial x:Key="backFont" Brush="Firebrick"></DiffuseMaterial>
            <DiffuseMaterial x:Key="texSand">
                <DiffuseMaterial.Brush>
                    <ImageBrush ImageSource="C:\Users\Julko\Documents\csharpprojects\wpf\3dProj\WpfApp2\WpfApp2\sand.jpg"></ImageBrush>
                </DiffuseMaterial.Brush>
            </DiffuseMaterial>
        </Grid.Resources>
        
        <Viewport3D Name ="viewPort" Width="640" Height="480">
            <Viewport3D.Camera>
                <PerspectiveCamera Position="57, 240, 41" LookDirection="-0.2, 0, -0.9" UpDirection="0, 1, 0" NearPlaneDistance="0.02" FarPlaneDistance="1000" FieldOfView="45">
                </PerspectiveCamera>
            </Viewport3D.Camera>
       
            <ModelVisual3D>
                <ModelVisual3D.Content>
                    <Model3DGroup>
                        <DirectionalLight Color="GreenYellow" Direction="1, -1, -1"/>
                        <GeometryModel3D>
                            <GeometryModel3D.Geometry>
                                <MeshGeometry3D Positions="0.293893 -0.5 0.404509  0.475528 -0.5 0.154509  0 0.5 0  0.475528 -0.5 0.154509  0 0.5 0  0 0.5 0  0.475528 -0.5 0.154509  0.475528 -0.5 -0.154509  0 0.5 0  0.475528 -0.5 -0.154509  0 0.5 0  0 0.5 0  0.475528 -0.5 -0.154509  0.293893 -0.5 -0.404509  0 0.5 0  0.293893 -0.5 -0.404509  0 0.5 0  0 0.5 0  0.293893 -0.5 -0.404509  0 -0.5 -0.5  0 0.5 0  0 -0.5 -0.5  0 0.5 0  0 0.5 0  0 -0.5 -0.5  -0.293893 -0.5 -0.404509  0 0.5 0  -0.293893 -0.5 -0.404509  0 0.5 0  0 0.5 0  -0.293893 -0.5 -0.404509  -0.475528 -0.5 -0.154509  0 0.5 0  -0.475528 -0.5 -0.154509  0 0.5 0  0 0.5 0  -0.475528 -0.5 -0.154509  -0.475528 -0.5 0.154509  0 0.5 0  -0.475528 -0.5 0.154509  0 0.5 0  0 0.5 0  -0.475528 -0.5 0.154509  -0.293892 -0.5 0.404509  0 0.5 0  -0.293892 -0.5 0.404509  0 0.5 0  0 0.5 0  -0.293892 -0.5 0.404509  0 -0.5 0.5  0 0.5 0  0 -0.5 0.5  0 0.5 0  0 0.5 0  0 -0.5 0.5  0.293893 -0.5 0.404509  0 0.5 0  0.293893 -0.5 0.404509  0 0.5 0  0 0.5 0  " 
    Normals="0.7236065,0.4472139,0.5257313  0.2763934,0.4472138,0.8506507  0.5308242,0.4294462,0.7306172  0.2763934,0.4472138,0.8506507  0,0.4294458,0.9030925  0.5308242,0.4294462,0.7306172  0.2763934,0.4472138,0.8506507  -0.2763934,0.4472138,0.8506507  0,0.4294458,0.9030925  -0.2763934,0.4472138,0.8506507  -0.5308242,0.4294462,0.7306172  0,0.4294458,0.9030925  -0.2763934,0.4472138,0.8506507  -0.7236065,0.4472139,0.5257313  -0.5308242,0.4294462,0.7306172  -0.7236065,0.4472139,0.5257313  -0.858892,0.429446,0.279071  -0.5308242,0.4294462,0.7306172  -0.7236065,0.4472139,0.5257313  -0.8944269,0.4472139,0  -0.858892,0.429446,0.279071  -0.8944269,0.4472139,0  -0.858892,0.429446,-0.279071  -0.858892,0.429446,0.279071  -0.8944269,0.4472139,0  -0.7236065,0.4472139,-0.5257313  -0.858892,0.429446,-0.279071  -0.7236065,0.4472139,-0.5257313  -0.5308242,0.4294462,-0.7306172  -0.858892,0.429446,-0.279071  -0.7236065,0.4472139,-0.5257313  -0.2763934,0.4472138,-0.8506507  -0.5308242,0.4294462,-0.7306172  -0.2763934,0.4472138,-0.8506507  0,0.4294458,-0.9030925  -0.5308242,0.4294462,-0.7306172  -0.2763934,0.4472138,-0.8506507  0.2763934,0.4472138,-0.8506507  0,0.4294458,-0.9030925  0.2763934,0.4472138,-0.8506507  0.5308249,0.4294459,-0.7306169  0,0.4294458,-0.9030925  0.2763934,0.4472138,-0.8506507  0.7236068,0.4472141,-0.5257306  0.5308249,0.4294459,-0.7306169  0.7236068,0.4472141,-0.5257306  0.8588922,0.4294461,-0.27907  0.5308249,0.4294459,-0.7306169  0.7236068,0.4472141,-0.5257306  0.8944269,0.4472139,0  0.8588922,0.4294461,-0.27907  0.8944269,0.4472139,0  0.858892,0.429446,0.279071  0.8588922,0.4294461,-0.27907  0.8944269,0.4472139,0  0.7236065,0.4472139,0.5257313  0.858892,0.429446,0.279071  0.7236065,0.4472139,0.5257313  0.5308242,0.4294462,0.7306172  0.858892,0.429446,0.279071  "                   TriangleIndices="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 " />
                            </GeometryModel3D.Geometry></GeometryModel3D>
                        <GeometryModel3D Geometry='{StaticResource meshPyramid}' Material='{StaticResource matFont}' BackMaterial='{StaticResource backFont}'/>
                        <GeometryModel3D Geometry='{StaticResource desertFloor}' Material='{StaticResource texSand}'/>
                    </Model3DGroup>
                </ModelVisual3D.Content>
            </ModelVisual3D>
            
        </Viewport3D>
    </Grid>
</Window>

Answer 1

The position of camera is wrong. Change it eg to the

PerspectiveCamera Position="57, 41, 240"

and you will see pyramid. Just do play with Position , UpDirection , LookDirection .
Also do swap Material and BackMaterial by meshPyramid :

<GeometryModel3D Geometry='{StaticResource meshPyramid}' Material='{StaticResource backFont}' BackMaterial='{StaticResource matFont}'/>