I currently have a WPF windows with a Canvas is 600 x 400. Is it possible to scale or automatically zoom in so that the lines take up as much as the 600x600 as possible?
<Border>
<Canvas x:Name="cMap" Width="600" Height="400">
<Line X1="5" Y1="5" X2 ="10" Y2="10" StrokeThickness="2" Stroke="Black"/>
<Line X1="10" Y1="10" X2 ="15" Y2="25" StrokeThickness="2" Stroke="Black"/>
</Canvas>
</Border>
My intention will be to add lines programmatically via code instead of XAML.
Thanks.
Not sure what is your exact usecase, but you could probably benefit by using ViewBox:
<Border>
<Viewbox Stretch="Uniform">
<Canvas x:Name="cMap" Width="15" Height="25">
<Canvas.LayoutTransform>
<ScaleTransform />
</Canvas.LayoutTransform>
<Line X1="5" Y1="5" X2 ="10" Y2="10" StrokeThickness="2" Stroke="Black"/>
<Line X1="10" Y1="10" X2 ="15" Y2="25" StrokeThickness="2" Stroke="Black"/>
</Canvas>
</Viewbox>
</Border>
Hope this helps you!
To draw lines in code you shoud do something like this:
Line line = new Line();
Thickness thickness = new Thickness(101,-11,362,250);
line.Margin = thickness;
line.Visibility = System.Windows.Visibility.Visible;
line.StrokeThickness = 4;
line.Stroke = System.Windows.Media.Brushes.Black;
line.X1 = 10;
line.X2 = 40;
line.Y1 = 70;
line.Y2 = 70;
and don't forget to add:
myCanvas.Children.Add(line);
to put those line in some place
from: Drawing lines in code using C# and WPF
To resize your canvas please read this:
Canvas is the only panel element that has no inherent layout
characteristics. A Canvas has default Height and Width properties of
zero, unless it is the child of an element that automatically sizes
its child elements. Child elements of a Canvas are never resized, they
are just positioned at their designated coordinates. This provides
flexibility for situations in which inherent sizing constraints or
alignment are not needed or wanted. For cases in which you want child
content to be automatically resized and aligned, it is usually best to
use a Grid element.
So as a solution you would make it inside a GRID or using the following code:
public class CanvasAutoSize : Canvas
{
protected override System.Windows.Size MeasureOverride(System.Windows.Size constraint)
{
base.MeasureOverride(constraint);
double width = base
.InternalChildren
.OfType<UIElement>()
.Max(i => i.DesiredSize.Width + (double)i.GetValue(Canvas.LeftProperty));
double height = base
.InternalChildren
.OfType<UIElement>()
.Max(i => i.DesiredSize.Height + (double)i.GetValue(Canvas.TopProperty));
return new Size(width, height);
}
}
at your XAML:
<local:CanvasAutoSize VerticalAlignment="Top" HorizontalAlignment="Left"></local:CanvasAutoSize>
from: WPF: How to make canvas auto-resize?
Related
So I am creating a "Map Viewer" for a program I am working on. Basically I want to display a map and have it resize the image to fit in the grid. For this I am using Viewbox to hold the image and resize it. I was attempting to use this code to reveal the map but it does not center the circle on the mouse and it does not retain the revealed portions of the map (it ONLY reveals where the mouse is and not where it has been).
Here is the XAML:
<Viewbox x:Name="MapHolder" Grid.Column="0" Grid.Row="0" Grid.ColumnSpan="1" Grid.RowSpan="7" Margin="25,5,25,15">
<Image x:Name="SelectedMap" Source="/wizard_dungeon.jpg" Stretch="Uniform" MouseMove="SelectedMap_MouseMove" >
<Image.OpacityMask>
<VisualBrush Stretch="None" >
<VisualBrush.Visual>
<Ellipse Width="400" Height="400" StrokeThickness="1" Fill="Black"/>
</VisualBrush.Visual>
<VisualBrush.RelativeTransform>
<TransformGroup>
<TranslateTransform x:Name="OpacityFilterTransform" X="1" Y="1"/>
</TransformGroup>
</VisualBrush.RelativeTransform>
</VisualBrush>
</Image.OpacityMask>
</Image>
</Viewbox>
And the code-behind:
private void SelectedMap_MouseMove(object sender, MouseEventArgs e)
{
var position = e.GetPosition(this);
var height = MapHolder.ActualHeight;
var width = MapHolder.ActualWidth;
// with the position values, interpolate a TranslateTransform for the opacity mask
var transX = position.X / width;
var transY = position.Y / height;
OpacityFilterTransform.X = transX - 0.5;
OpacityFilterTransform.Y = transY - 0.5;
}
I want there to basically be a Image under a Black screen and I can erase the black screen to reveal the image in the areas I have erased.
I'm receiving a live video from a DJI drone in a SwapChainPanel and I'm using template matching from OpenCV to find an image inside the frames of the video.
I want to draw a rectangle when the subgimage is detected, but there are white spaces in both sides of the frames and I don't know how to get the size of those or align the image to the left and top.
Here is the XAML:
<SwapChainPanel x:Name="swapChainPanel" Grid.Column="8" Grid.ColumnSpan="4" Grid.Row="2" Grid.RowSpan="11">
<Canvas>
<Rectangle x:Name="rectFiducial" Visibility="Collapsed" Stroke="Red"></Rectangle>
<Rectangle Stroke="Blue" Width="400" Height="400"></Rectangle>
</Canvas>
</SwapChainPanel>
Here is the code when I try to draw the rectangle with the results of the Template Matching:
SoftwareBitmap inputBitmap = SoftwareBitmap.CreateCopyFromBuffer(CryptographicBuffer.CreateFromByteArray(imageData),
BitmapPixelFormat.Rgba8,
imageWidth,
imageHeight);
if (inputBitmap.BitmapPixelFormat != BitmapPixelFormat.Bgra8
|| inputBitmap.BitmapAlphaMode != BitmapAlphaMode.Premultiplied)
{
inputBitmap = SoftwareBitmap.Convert(inputBitmap, BitmapPixelFormat.Bgra8, BitmapAlphaMode.Premultiplied);
}
int x = 0, y = 0, matchMethod = 0;
double matchResult = 0;
Stopwatch testWatch = new Stopwatch();
testWatch.Start();
await txtMatchMethod.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
int.TryParse(txtMatchMethod.Text, out matchMethod);
});
OpenCV.TemplateMatching(inputBitmap, template, matchMethod, out x, out y, out matchResult);
testWatch.Stop();
await txtMatchTime.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
txtMatchTime.Text = testWatch.ElapsedMilliseconds.ToString();
txtMatchResult.Text = matchResult.ToString();
double swapX = x * swapChainPanel.ActualWidth / imageWidth;
double swapY = y * swapChainPanel.ActualHeight / imageHeight;
double swapWidth = template.PixelWidth * swapChainPanel.ActualWidth / imageWidth;
double swapHeight = template.PixelHeight * swapChainPanel.ActualHeight / imageHeight;
rectFiducial.SetValue(Canvas.LeftProperty, swapX);
rectFiducial.SetValue(Canvas.TopProperty, swapY);
rectFiducial.Width = swapWidth;
rectFiducial.Height = swapHeight;
rectFiducial.Visibility = Visibility.Visible;
});
}
There is an event where I can get the bytes of the image and I tried to display it in an Image inside a Canvas, but the image didn't stretch to fit the canvas size.
Edit
I realized that I'm calculating the position based on the width and height of the SwapChainPanel, but I have to calculate it with the width and height of the image inside.
So I would need to get the data of the resized image that is inside the SwapChainPanel and the padding of the left side.
Well, I couldn't find a solution for the SwapChainPanel, but I found a solution with the image and the canvas.
I was trying to make something like this:
<Canvas x:Name="canvas" Grid.Column="8" Grid.ColumnSpan="4" Grid.Row="4" Grid.RowSpan="11">
<Image x:Name="imgDrone" HorizontalAlignment="Left"/>
<Rectangle x:Name="rectFiducial" Visibility="Collapsed" Stroke="Red"></Rectangle>
<Rectangle Stroke="Blue" Width="400" Height="400"></Rectangle>
</Canvas>
But I couldn't stretch the image, it was displayed with it's real size.
So instead of declaring the image inside the Canvas I just took it out and set it's column and row with the same values of the canvas.
Like this:
<Image x:Name="imgDrone" HorizontalAlignment="Left" Grid.Column="8" Grid.ColumnSpan="2" Grid.Row="2" Grid.RowSpan="11"/>
<Canvas x:Name="canvas" Grid.Column="8" Grid.ColumnSpan="4" Grid.Row="4" Grid.RowSpan="11">
<Rectangle x:Name="rectFiducial" Visibility="Collapsed" Stroke="Red"></Rectangle>
<Rectangle Stroke="Blue" Width="400" Height="400"></Rectangle>
</Canvas>
I am trying to make a drawing program in WPF but I ran into some problems.
I can succesfully draw lines (yeeey) but I also want the ability to fill out space (my method is stacking alot of recntagles with the same starting point).
but when I switch my radiobutton from "line" to "fill" it doesnt draw anything.
-- drawing (boolean) is used to create the starting point of filling
Code
private void cnvs_MouseMove(object sender, MouseEventArgs e)
{
if (e.LeftButton == MouseButtonState.Pressed && linemode.IsChecked == true)
{
Line line = new Line();
drawing = true;
line.Stroke = currentbrush;
line.X1 = currentPoint.X - 9;
line.Y1 = currentPoint.Y - 9;
line.X2 = e.GetPosition(this).X - 9;
line.Y2 = e.GetPosition(this).Y - 9;
currentPoint = e.GetPosition(this);
cnvs.Children.Add(line);
} else if (cnvs.IsFocused == true)
{
if (!drawing) rectbeggining = e.GetPosition(this);
drawing = true;
Rectangle rect = new Rectangle();
rect.Stroke = currentbrush;
rect.StrokeThickness = 1;
rect.Height = (Math.Abs(e.GetPosition(this).Y) - Math.Abs(rectbeggining.Y));
rect.Width = (rectbeggining.X - e.GetPosition(this).X);
Canvas.SetLeft(rect, e.GetPosition(this).X);
Canvas.SetTop(rect, Math.Abs(e.GetPosition(this).Y));
cnvs.Children.Add(rect);
}
if(e.LeftButton == MouseButtonState.Released) drawing = false;
}
Xaml
<Grid>
<Border Name="CanvasBorder" BorderBrush="Black" BorderThickness="2" Margin="8,8,207,9"/>
<Canvas HorizontalAlignment="Left" Height="972" Margin="10,10,0,0" VerticalAlignment="Top" Width="1493" MouseDown="Canvas_MouseDown" MouseMove="cnvs_MouseMove" Name="cnvs">
<Canvas.Background>
<SolidColorBrush Color="White" Opacity="0"/>
</Canvas.Background>
</Canvas>
<ComboBox Name="selectcolor" Margin="1510,10,10,945" SelectedItem="Black" SelectionChanged="selectcolor_SelectionChanged" SelectedIndex="7">
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Rectangle Fill="{Binding Name}" Width="16" Height="16" Margin="0,2,5,2" />
<TextBlock Text="{Binding Name}" />
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
<Button Content="Reset" HorizontalAlignment="Left" Margin="1510,939,0,0" VerticalAlignment="Top" Width="192" Click="Button_Click" Height="44"/>
<RadioButton GroupName="selectedMode" Name="linemode" Content="Line" HorizontalAlignment="Left" Margin="1510,232,0,0" VerticalAlignment="Top" IsChecked="True"/>
<RadioButton GroupName="selectedMode" Name="fillmode" Content="Fill" HorizontalAlignment="Left" Margin="1510,247,0,0" VerticalAlignment="Top"/>
<Label Content="Mode:" HorizontalAlignment="Left" Margin="1510,206,0,0" VerticalAlignment="Top"/>
</Grid>
I'm working on the map editor for generalstaff at the moment. You pick between line or area types of terrain, draw and when you finish a stroke it's processed.
Unless I've misunderstood your purpose that sounds pretty much like you're doing.
I essentially have an inkcanvas on top of a canvas.
It's rather more complicated than that. I bind viewmodels to an itemscontrol which has a canvas as it's itemspresenter and template data into the pieces of terrain.
I can bore at length on this stuff.
I use inkcanvas because it gives you smoother results than drawing directly on a canvas. I started off using a canvas like that but you get jiggly bits..
The strokeschanged event is used to tell when a stroke on the inkcanvas has finished.
Each stroke has a styluspointcollection StylusPoints and you can iterate through that to get the points.
Once you have the points, you can build a polygon.
I do that by templating and I bind the Points property of a Polygon to a Pointcollection from a viewmodel.
A polygon has a Fill property which you can set or bind to a solidcolorbrush.
And in that way you can draw any shape you like, then fill it with one colour.
This is a very basic question.
I want to be able to add a shape defining different opacity for fill and for stroke.
If I add this:
Ellipse e = new Ellipse();
e.Width = e.Height = 150;
e.Stroke = Brushes.Aqua;
e.Fill = Brushes.Chartreuse;
e.StrokeThickness = 20;
e.Opacity = .25;
plotCanvas.Children.Add(e);
I can only set 1 opacity. Instead I would like the fill to be 0.25 opaque and the stroke to be 1.0 opaque.
Thank you
Patrick
Setting the Opacity on the Ellipse will set the opacity for the entire control. What you want to do is create dedicated Brushes for Fill and Stroke, and control the opacity on the Brushes, i.e. :
SolidColorBrush strokeBrush = new SolidColorBrush(Colors.Aqua);
strokeBrush.Opacity = .25d;
Alternatively, you could control the Alpha channel of the brush:
SolidColorBrush strokeBrush = new SolidColorBrush(Color.FromArgb(/*a, r, g, b*/));
<Ellipse Stroke="Red" Width="200" Height="100" StrokeThickness="5">
<Ellipse.Fill>
<SolidColorBrush Color="Green" Opacity=".25"></SolidColorBrush>
</Ellipse.Fill>
</Ellipse>
Or in C# you can set the fill to a new SolidColorBrush with the desired opacity for the Opacity property.
You can't set the opacity twice for a single Shape object. Insteaf of setting the opacity twice you can add a Border to your Ellipse:
<Canvas x:Name="MyCanvas" Width="1000" Height="1000" Background="White">
<Border BorderBrush="Black" Opacity="1" BorderThickness="10" CornerRadius="{Binding RelativeSource={RelativeSource Self}, Path=ActualHeight}">
<Ellipse Height="150" Width="150" Fill="Black" Opacity="0.25"></Ellipse>
</Border>
But since the Border is a rectangle which encloses the ellipse, you also need to set the cornerradius
I have an image control sits inside a Grid control. I already have a button to enable zoom-in to this image. After zoom-in, the Horizontal/vertical scroll bars are displayed. And then I rotate the image contained grid, the image and the grid scroll bar are messed up. How should I incorporate both zoom-in and rotate for the image control? The following are the code that I am using in my project.
The image control zoom-in code I used (x is the image control):
if ((x as Image) != null) { x.Height = x.Height * 1.3; x.Width = x.Width * 1.3; }
The rotation code I used (x is the image control):
if ((x as Image) != null)
{
RotateTransform rotate = new RotateTransform(); rotate.Angle = rotateAngle;
rotate.CenterX = x.Width / 2;
rotate.CenterY = x.Height / 2;
x.RenderTransform = rotate;
};
The XAML is:
<ScrollViewer x:Name="scrollViewer" Height="480" Width="615"
VerticalScrollBarVisibility="Auto"
HorizontalScrollBarVisibility="Auto">
<ScrollViewer.Content>
<Grid x:Name="ImageGrid">
<StackPanel x:Name="ImageStackPanel">
<Image Source="..." VerticalAlignment="Center" Width="220" Height="170" ></Image>
</StackPanel>
</Grid>
</ScrollViewer.Content>
</ScrollViewer>
Does anybody have any existing code snippet that I can borrow to resolve this trick?
I think you need to use TransformGroup to use more than one transform at the time:
ScaleTransform myScaleTransform = new ScaleTransform();
myScaleTransform.ScaleY = 3;
RotateTransform myRotateTransform = new RotateTransform();
myRotateTransform.Angle = 45;
// Create a TransformGroup to contain the transforms
// and add the transforms to it.
TransformGroup myTransformGroup = new TransformGroup();
myTransformGroup.Children.Add(myScaleTransform);
myTransformGroup.Children.Add(myRotateTransform);
// Associate the transforms to the image.
x.RenderTransform = myTransformGroup;
This may work for your needs:
<Image x:Name="image" Source="myImageSource" Stretch="Uniform"
HorizontalAlignment="Center" VerticalAlignment="Center"
RenderTransformOrigin="0.5, 0.5">
<Image.RenderTransform>
<TransformGroup>
<RotateTransform x:Name="Rotate"/>
<ScaleTransform x:Name="Scale" />
</TransformGroup>
</Image.RenderTransform>
</Image>
code behind:
Rotate.Angle = 45;
Scale = 0.25;
You may be missing the LayoutTransformer from the Silverlight Toolkit, and the AnimationMediator from one of the Toolkit developers.
With the LayoutTransformer you can set its content to anything, not just images, and apply any transformation with it, and as opposed to the usual RenderTransform, it will affect layout and actual sizes.
I have a similar scenario and I use it like this:
<Grid>
<fs:AnimationMediator x:Name="RotateMediator" LayoutTransformer="{Binding ElementName=LayoutTransformer}" AnimationValue="{Binding Angle, ElementName=RotateTransform, Mode=TwoWay}" />
<fs:AnimationMediator x:Name="ScaleXMediator" LayoutTransformer="{Binding ElementName=LayoutTransformer}" AnimationValue="{Binding ScaleX, ElementName=ScaleTransform, Mode=TwoWay}" />
<fs:AnimationMediator x:Name="ScaleYMediator" LayoutTransformer="{Binding ElementName=LayoutTransformer}" AnimationValue="{Binding ScaleY, ElementName=ScaleTransform, Mode=TwoWay}" />
<tkt:LayoutTransformer x:Name="LayoutTransformer" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
<tkt:LayoutTransformer.LayoutTransform>
<TransformGroup>
<RotateTransform x:Name="RotateTransform" />
<ScaleTransform x:Name="ScaleTransform" />
</TransformGroup>
</tkt:LayoutTransformer.LayoutTransform>
<Image x:Name="MyImage" Source="mysource.png" Width="600" Height="800" />
</tkt:LayoutTransformer>
</Grid>
Because of the lack of MultiBinding you'd probably additionally have to manually handle the input value (from Slider controls etc) changed events and then set the AnimationValues of RotateMediator etc accordingly.