Mipmapping in wpf

Question

I'm new to 'wpf' and I've come over the following problem: In my project I try to use small resolution .png as texture for a model. When I disable mipmapping in Blender (where I built the cube) the result is just what I want:

no mipmapping

But in the wpf project the blurred effect never turns off:

wpf result

Here is my code:

<Window x:Class="GCS.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="MainWindow" Height="504" Width="525" ShowInTaskbar="True">
<Grid>
        <Viewport3D Name="myViewport"
            xmlns="http://schemas.microsoft.com/netfx/2007/xaml/presentation"
            xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
            <Viewport3D.Resources>
                <MaterialGroup x:Key="Material">
                    <DiffuseMaterial>
                        <DiffuseMaterial.Brush>
                            <ImageBrush RenderOptions.BitmapScalingMode="NearestNeighbor" ViewportUnits="Absolute" ImageSource="char.png"/>
                        </DiffuseMaterial.Brush>
                    </DiffuseMaterial>
                </MaterialGroup>
            </Viewport3D.Resources>
            <Viewport3D.Camera>
                <PerspectiveCamera Position="7.8,-11,-0.8" NearPlaneDistance="1" FarPlaneDistance="50" LookDirection="-0.4,0.9,-0.3" UpDirection="0,0,1" FieldOfView="15"/>
            </Viewport3D.Camera>
            <Viewport3D.Children>
                <ModelVisual3D>
                    <ModelVisual3D.Content>
                        <Model3DGroup>
                            <GeometryModel3D Material="{StaticResource Material}">
                                <GeometryModel3D.Transform>
                                    <Transform3DGroup>
                                        <TranslateTransform3D OffsetZ="0" OffsetX="0" OffsetY="-7"/>
                                        <ScaleTransform3D ScaleZ="1" ScaleY="1" ScaleX="1"/>
                                        <RotateTransform3D>
                                            <RotateTransform3D.Rotation>
                                                <AxisAngleRotation3D Axis="1,0,0" Angle="92"/>
                                            </RotateTransform3D.Rotation>
                                        </RotateTransform3D>
                                        <TranslateTransform3D OffsetZ="0" OffsetX="0" OffsetY="7"/>
                                        <TranslateTransform3D OffsetZ="-6.622" OffsetX="0" OffsetY="-0.023"/>
                                    </Transform3DGroup>
                                </GeometryModel3D.Transform>
                                <GeometryModel3D.Geometry>
                                    <MeshGeometry3D
                                        Normals="-1,0,0 -1,0,0 -1,0,0 -1,0,0 0,0,-1 0,0,-1 0,0,-1 0,0,-1 1,0,0 1,0,0 1,0,0 1,0,0 0,0,1 0,0,1 0,0,1 0,0,1 0,-1,0 0,-1,0 0,-1,0 0,-1,0 0,1,0 0,1,0 0,1,0 0,1,0"
                                        Positions="-1,6,-1 -1,6,1 -1,8,1 -1,8,-1 -1,8,-1 1,8,-1 1,6,-1 -1,6,-1 1,8,-1 1,8,1 1,6,1 1,6,-1 -1,6,1 1,6,1 1,8,1 -1,8,1 -1,6,1 -1,6,-1 1,6,-1 1,6,1 1,8,1 1,8,-1 -1,8,-1 -1,8,1"
                                        TextureCoordinates="0,0.5 0.125,0.5 0.125,0.25 0,0.25 0.5,0.25 0.375,0.25 0.375,0.5 0.5,0.5 0.375,0.25 0.25,0.25 0.25,0.5 0.375,0.5 0.125,0.5 0.25,0.5 0.25,0.25 0.125,0.25 0.375,0.25 0.375,0 0.25,0 0.25,0.25 0.25,0.25 0.25,0 0.125,0 0.125,0.25"
                                        TriangleIndices="0 1 2 0 2 3 4 5 6 4 6 7 8 9 10 8 10 11 12 13 14 12 14 15 16 17 18 16 18 19 20 21 22 20 22 23"/>
                                </GeometryModel3D.Geometry>
                            </GeometryModel3D>
                        </Model3DGroup>
                    </ModelVisual3D.Content>
                </ModelVisual3D>
                <ModelVisual3D>
                    <ModelVisual3D.Content>
                        <AmbientLight Color="#ffffff"/>
                    </ModelVisual3D.Content>
                </ModelVisual3D>
            </Viewport3D.Children>
        </Viewport3D>
</Grid>

I've done a lot of search on the Internet and tried many approaches: enforced software rendering, used DrawingBrush instead of ImageBrush but the result is the same. Is there any way to overcome such rendering?

Answer 1

Try the following approach using VisualBrush - it produces clear, aliased texturing:

        <DiffuseMaterial x:Key="Material">
            <DiffuseMaterial.Brush>
                <VisualBrush RenderOptions.CachingHint="Cache">
                    <VisualBrush.Visual>
                        <Image Source="char.png" RenderOptions.BitmapScalingMode="NearestNeighbor" />
                    </VisualBrush.Visual>
                </VisualBrush>
            </DiffuseMaterial.Brush>
        </DiffuseMaterial>
    </Grid.Resources>


    <Viewport3D Name="myViewport">
        <Viewport3D.Camera>
            <PerspectiveCamera Position="0 0.5 1.5" LookDirection="0 0 -1"
                           UpDirection="0 1 0" FieldOfView="120" />
        </Viewport3D.Camera>
        <Viewport3D.Children>
            <ModelVisual3D>
                <ModelVisual3D.Content>
                    <GeometryModel3D Material="{StaticResource Material}">

                        <GeometryModel3D.Geometry>
                            <MeshGeometry3D
                         Positions="0 0 0, 0 1 0, 1 0 0, 1 1 0"
                         TriangleIndices="0 2 3, 0 3 1"
                         TextureCoordinates="0 1, 0 0, 1 1, 1 0" />
                        </GeometryModel3D.Geometry>

                    </GeometryModel3D>
                </ModelVisual3D.Content>
            </ModelVisual3D>

            <ModelVisual3D>
                <ModelVisual3D.Content>
                    <AmbientLight Color="#ffffff"/>
                </ModelVisual3D.Content>
            </ModelVisual3D>
        </Viewport3D.Children>
    </Viewport3D>
</Grid>