How Scaling will affect position of element in canvas - wpf

I am having one canvas. I have added one text box to it using canvas.left and canvas.right property.And already there is a image inside that container. And am applying some matrix transform to my text box and image in order to zoom it.
tb.RenderTransform = new MatrixTransform(m);
But now the text box is getting moved to different position. But It should get zoomed along with the image. How to achieve that.?

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Aligning components with each other in WPF

A WPF application consists of a uniform grid of arbitrary size. Each cell in the grid contains a canvas. Each canvas is a target for a drag and drop operation.
When I drag another canvas and drop it onto a canvas inside the grid I want the top left corners of the dragged canvas(source) and the target canvas to align, essentially placing the source on top of the target. The behaviour I'm looking for is a snap-to-grid effect.
Currently when I use element.GetValue(Canvas.LeftProperty) the result in NaN. The problem is to determine the position of the corner for a canvas inside the grid, but relative to the entire window. I would prefer to use the grid, as it automatically resize as the window resize.
Is it possible to get the actual position of a canvas inside a grid even when the grid size changed or alternatively specify a canvas to be aligned to another canvas inside the grid?
This problem was solved by drawing each canvas onto another canvas by specifying the top and left properties of the canvas, I had to scratch the grid. I specified the position of every canvas by using
Canvas.SetLeft(Me, position.X)
Canvas.SetTop(Me, position.Y)
where Me is an instance of the canvas.
It is now easy to get the top and left properties of every canvas. The only problem now is I have to implement the resizing of every canvas manually.

How can you use an ImageBrush to display a specified area of an image as the background of a rectangle?

I'm trying to add a zoom feature for an image viewer control I'm creating. When viewing the image, holding down the left mouse button brings up a rounded rectangle that is zoomed into the image. I figure I can use An ImageBrush as the background but I can't figure out how to make it just display a specified area of the image. Can this even be done?
By using the Viewbox.

Panning the display area in WPF

The application will have a menu strip on top and the rest will display lines and shapes. I want to be able to drag and pan the main display area by clicking it and dragging it in any direction.
I am currently drawing items using pixel values (for example a line drawn from (1042,54)to(1240,104). But I think a monitor with a smaller resolution will not be able to display that object. That is why I want to be able to pan the display area.
The lines and shapes are currently being drawn on a gird that I placed inside the window.
If you place the canvas inside a ScrollViewer then if the canvas is larger than the application window it will be displayed with scroll bars.
You can then address points on the canvas with values relative to the canvas rather than the screen.

Getting position of rendered image inside Image control

I have an Image control with Stretch==Uniform which means larger images will be scaled down. In my case the Image control fills the whole client space, the scaled down image is being displayed centered inside the control. What now will happen: the size of the rendered image and the Image control do not have the same size - the Image control is usually larger than its content (since I use uniform stretching).
I now need to know the position of the actual image inside the Image control. Some background: the user can place a rectangle on the image to crop it. To match the rectangle with the image coordinates I need to know exactly where the image is.
Is there a way to determine the position of the rendered image inside the Image control? Or is the only solution to make the control the same size as the image content?
To get more control, you might want to put the image on a canvas inside a viewbox.
That way you get pixel control via the canvas, but a scaled view via the outer viewbox. Set the canvas dimensions to match the image and add any decorations to the canvas.
You may need to inverse-scale the rectangle stroke width so that it is visible when the canvas is small.

WPF/C#: Images rotating from a listview?

I just want ask for your comments/suggestions on how to create a customized listview (if that's a good implementation) in WPF that displays images coming from a table from a database (more like a playlist) that rotates similar to a film (moving horizontally - on loop)
Any ideas?
If you have a list of Images, you can create an Image control for each one, put each Image control in a horizontal StackPanel, put the StackPanel inside a Canvas (of whatever size of the "film"), and animate the Left property of the Canvas to have the images roll.
Of course, if you need that the images wrap (the first one after the last one), you could forget about the StackPanel and move each Image separately.

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