我想在WriteableBitmap 上绘制一些文本。这似乎不可能，但我发现在 C# 中将 WriteableBitmap 转换为位图 here和 this .
调用如下(也包含转换方法):
// Draw dino names...
Graphics g = Graphics.FromImage(BitmapFromWriteableBitmap(writeableBitmap));
g.DrawString(Dinosaurs[i].PersonalName, new Font("Tahoma", 40), System.Drawing.Brushes.White, new PointF((float)Dinosaurs[i].Head.X, (float)Dinosaurs[i].Head.Y));
} // for i
}// DrawDinos2d
private System.Drawing.Bitmap BitmapFromWriteableBitmap(WriteableBitmap writeBmp)
{
System.Drawing.Bitmap bmp;
using (MemoryStream outStream = new MemoryStream())
{
BitmapEncoder enc = new BmpBitmapEncoder();
enc.Frames.Add(BitmapFrame.Create((BitmapSource)writeBmp));
enc.Save(outStream);
bmp = new System.Drawing.Bitmap(outStream);
}
return bmp;
}
我检查了调试器，g 有一个很好的值(不为空)，但屏幕上没有绘制任何东西。我还应该提到，传递给 DrawString 的字符串很好，而且点的 X、Y 也很好(大约 1000,800 的正整数)。我认为它要么在屏幕上绘制，要么 X、Y 坐标转换不正确。
有什么想法吗？谢谢。
这是 XAML(如果有帮助的话):
<Window x:Class="DinosaurIsland.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Dinosaur Island" Height="600" Width="600" WindowState="Normal" Icon="/DinosaurIsland;component/Icon1.ico" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" WindowStartupLocation="CenterOwner">
<Window.Resources>
<ResourceDictionary>
<DataTemplate DataType="{x:Type BitmapImage}">
<Image Source="{Binding}" />
</DataTemplate>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="Resources.xaml"/>
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Window.Resources>
<DockPanel>
<Menu x:Name="MainMenu" DockPanel.Dock="Top">
<MenuItem Header="_File">
<MenuItem Header="_Open Dinosaur Island 'snapshot' file..." x:Name="OpenSnapshotFile" Click="OpenSnapshotFile_click" />
<MenuItem Header="_Save"/>
<MenuItem Header="_Exit" x:Name="ExitApp" Click="ExitAppClick" />
</MenuItem>
<MenuItem Header="_Height Map">
<MenuItem Header="Load Height Map..." Name="LoadHeightMap" Click="LoadHeightMapClick" />
<Separator />
<MenuItem Header="Display Height Map" x:Name="DisplayHeightMap" Click="DisplayHeightMapClick" />
</MenuItem>
<MenuItem Header="Terrain">
<MenuItem Header="Load Terrain Map..." x:Name="LoadTerrainMap" Click="LoadTerrainMap_Click" />
<MenuItem Header="Draw Terrain..." x:Name="DrawTerrain" Click="DisplayTerrainPaintBoxClick" />
<MenuItem Header="Save Terrain Map..." x:Name="SaveTerrainMap" Click="SaveTerrainMap_Click"/>
<MenuItem Header="Get Terrain Data From BMP..." x:Name="TerrainFromBMP" Click="TerrainFromBMP_Click" />
<Separator />
<MenuItem Header="Adjust Terrain Transparency..." x:Name="AdjustTerrainTransparency" Click="AdjustTerrainTransparency_Click"/>
<MenuItem Header="Display Terrain Map" x:Name="DisplayTerrainMap" Click="DisplayTerrainMap_Click"/>
</MenuItem>
<MenuItem Header="_Vegetation">
<MenuItem Header="Plant Vegetation..." x:Name="PlantVegetation" Click="PlantVegetation_Click" />
<Separator />
<MenuItem Header="Load Vegetation Map..." x:Name="LoadVegetation" Click="LoadVegetation_Click" />
<MenuItem Header="Save Vegetation Map..." x:Name="SaveVegetation" Click="SaveVegetation_Click" />
<Separator />
<MenuItem Header="Display Vegetation" Click="DisplayVegetation_Click" />
</MenuItem>
<MenuItem Header="Dinosaurs">
<MenuItem Header="Edit / Place Dinosaurs..." x:Name="EditDinosaurs" Click="EditDinosaurs_Click" />
<Separator />
<MenuItem Header="Load Dinosaur Map" Name="LoadDinosaurnMap" Click="LoadDinosaurs_Click"/>
<MenuItem Header="Save Dinosaur Map" Name="SaveDinosaurMap" Click="SaveDinosaurs_Click"/>
<Separator />
<MenuItem Header="Terrain/Slope Effect..." Name="TerrainSlope" Click="TerrainSlope_Click"/>
<MenuItem Header="Probability of Smelling Dinosaur..." Name="SmellProbability" Click="SmellProbability_Click"/>
</MenuItem>
<MenuItem Header="Time">
<MenuItem Header="Start..." x:Name="AdvanceTime" Click="StartTime_Click" />
<MenuItem Header="Stop..." x:Name="StopTime" Click="StopTime_Click" />
<Separator />
<MenuItem Header="Adjust Time Step..." x:Name="AdjustTimeStep" Click="AdjustTimeStep_Click"/>
</MenuItem>
<MenuItem Header="Debug">
<MenuItem Header="A* trace" Name="AStarTrace" Click="AStarTrace_Click" />
<MenuItem Header="Show Dinosaur Goals" Name="DinoGoals" Click="DinoGoals_Click" />
<MenuItem Header="Show Dinosaur Path" Name="DinoPath" IsChecked="False" Click="DinoPath_Click" />
<MenuItem Header="Show Predator Scent Path" Name="StinkPath" IsChecked="False" Click="StinkPath_Click" />
<MenuItem Header="Show Dinosaur Vision Angles" Name="VisionAngles" IsChecked="True" Click="VisionAngles_Click" />
<MenuItem Header="Show Dinosaur Axis" Name="DinoAxis" IsChecked="True" Click="DinoAxis_Click" />
</MenuItem>
<MenuItem Header="Help">
<MenuItem Header="About Dinosaur Island" Name="AboutDinosaurIsland" Click="AboutDinoIslandClick" />
</MenuItem>
</Menu>
<StatusBar DockPanel.Dock="Bottom">
<TextBlock Name="StatusBarField1">Location = X,Y</TextBlock>
<Separator/>
<TextBlock Name="StatusBarField2">Elevation = X</TextBlock>
<Separator/>
<TextBlock Name="StatusBarField3">Terrain = None</TextBlock>
<Separator/>
<TextBlock Name="StatusBarField4">Plants = None</TextBlock>
<Separator/>
<TextBlock Name="StatusBarField5">Dinosaurs = None</TextBlock>
<Separator/>
<TextBlock Name="StatusBarField6">Zoom</TextBlock>
<Separator/>
<TextBlock Name="StatusBarField7">Time 0:00</TextBlock>
<Separator/>
<TextBlock Name="StatusBarField8">Wind direction: 000</TextBlock>
<Separator/>
<TextBlock Name="StatusBarField9">Speed: 000</TextBlock>
</StatusBar>
<Label DockPanel.Dock="Bottom" Content="Scale = 2000 meters" Height="23" HorizontalAlignment="Center" Name="HorizScaleDisplayText" Width="127" />
<Label DockPanel.Dock="Bottom" Content="└───────────────────────────────┴───────────────────────────────────┘" Height="20" HorizontalAlignment="Center" Name="HorizScaleDisplayLine" Width="423" />
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Slider Grid.Column="0" Orientation="Vertical" HorizontalAlignment="Left" Minimum="1" x:Name="slider"/>
<ScrollViewer Name="scrollViewer" Grid.Column="1" VerticalScrollBarVisibility="Visible" HorizontalScrollBarVisibility="Visible" Margin="0,0,0,6">
<Grid Name="grid" Width="400" Height="400" RenderTransformOrigin="0.5,0.5">
<Grid.RowDefinitions>
<RowDefinition Height="37*" />
<RowDefinition Height="363*" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="297*" />
<ColumnDefinition Width="103*" />
</Grid.ColumnDefinitions>
<Grid.LayoutTransform>
<TransformGroup>
<ScaleTransform x:Name="scaleTransform"/>
</TransformGroup>
</Grid.LayoutTransform>
<Viewbox x:Name="viewBox" Margin="-35,-12,-22,22" Grid.ColumnSpan="2" Grid.RowSpan="2">
<ContentPresenter x:Name="contentPresenter" Width="350" Height="350" >
<ContentPresenter.Content>
<Image x:Name="image" Width="350" Height="350">
<Image.Source >
<BitmapImage x:Name="HeightMapImage" UriSource="DinoIslandLogo.bmp" />
</Image.Source>
</Image>
</ContentPresenter.Content>
</ContentPresenter>
</Viewbox>
</Grid>
</ScrollViewer>
</Grid>
</DockPanel>
这就是我显示位图的方式:
this.image.Source = writeableBitmap;
最佳答案
这解决了问题:
public void DrawDinoNames()
{
System.Drawing.Bitmap bmp;
bmp = BitmapFromWriteableBitmap(writeableBitmap);
Graphics g = Graphics.FromImage(bmp);
for (int i = 0; i < Dinosaurs.Count; i++)
{
g.DrawString(Dinosaurs[i].PersonalName, new Font("Tahoma", 14), System.Drawing.Brushes.White, new PointF((float)Dinosaurs[i].Head.X, (float)Dinosaurs[i].Head.Y));
}
this.image.Source = BitmapToImageSource(bmp, System.Drawing.Imaging.ImageFormat.Bmp);
}
关于c# - 在 WriteableBitmap 上绘制文本，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/19429563/