Drawing a XAML map in WPF - wpf

I'm working on a module that displays DWG files in WPF. I've managed to use CadLib library but it's working very slowly and I want to make it faster. I found out that if I convert that DWG file to SVG format and then print it to my XPS printer and rename the file to ZIP, I can get .page file which is basically a XAML file that displays the original SVG object in XAML.
I want to display this XAML code on a custom control and be able to pan / zoom it around. I tried to place this XAML code in a Canvas and it did manage to show up there, but now I'm stuck trying to pan / zoom the shape that was drawn there. Also, the mouse events are fired only when you click the actual drawing itself, and not the Canvas, which will be hard for the user to click...
Any help would be highly appreciated :)

You could try creating nested Canvases : One that holds the vectors and is moved on demand, one that is fixed and serves as the viewport. Haven't tried that, but it should be feasible...

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WPF MVVM binding controls with helper methods PDFTron PDFViewer

I am struggling with a WPF MVVM problem using a control that has helper functions and exposing those helper functions to my viewmodels.
I am using the PDFTron viewer control that shows a PDFDocument object. Items in that PDFDocument are specified in terms of a PDFTron.Rect structure with the elements measured in points(1/72th inch) and a page number
To help convert the coordinate systems to and from screen position the PDFTron ViewerControl has various function on itself.
e.g. To convert from a screen point
Double x, y;
int page = Control.GetPageNumberFromScreenPt(x, y);
Control.ConvScreenPtToPagePt(ref x, ref y, page);
To convert to a screen point is from the object being examined
PDFTron.Rect r = Control.GetScreenRectForAnnot(embeddedObject, pageNumber);
What the best way of calling/exposing or binding to functions like this between the view model(s) and the PDF control as I would really like to databind to coordinates.
For instance I have an adorner defined in XAML that allows me to move an image I have read from the embeddedobject about the page by dragging and I can also resize the image. The viewmodel knows As my view model knows the image the embedded object its page and Rectangle on that page, but as PDF coordinates. But this needs to be translated to screen coordinates for the X, Y, Width and Height for binding to the XAML Attributes. I cannot quite see how to do this as it seems beyond a dataconverter.
So the control in the xaml has attributes measured in screen units
AdornerLeft="{Binding Data.X, Mode=TwoWay}"
AdornerTop="{Binding Data.Y, Mode=TwoWay}"
AdornerWidth="{Binding Data.Width, Mode=TwoWay}"
AdornerHeight="{Binding Data.Height, Mode=TwoWay}"
If the X and Y change I need the change to be reflected eventually as the page,x,y coordinates of the viewer as they are what are used by the underlying model.
I did wonder would it be wise to make a series of dependency properties so if I change one it ripples the change through the others as a conversion? So for example I have a property ScreenY When that changes it updates PDFY and PDFPage and vice versa but that seems overly complicated. Any suggestions?
Typically what is done, is that during user interaction, so while your user is moving and resizing the image, everything is drawn overtop of PDFViewWPF viewer.
You can get a Canvas object from PDFViewWPF.GetCanvas() and then you can draw your image on that if you like.
At this point, nothing relates to the PDF, you are just dealing with WPF coordinates.
Only once the user is done moving and dragging, and you want to add the image to the PDF page, perhaps as a Stamp annotation, or even injecting the image into the page content, only then would you erase all your graphics, and inject the image into the PDF. Only at this point would you need to translate between coordinate systems.
Please take a closer look at the PDFViewWPFTools project, and see how something like the Rectangle annotations are created.
This post might provide additional clarity for you.
I ended up using the Prism library and the eventAggregator to pass the details back to a the View and get the results, also using events to refresh the view. The PDFWPFViewer MVVM sample from PdfTron beside having some issues with incorrect bindings, essentially uses a tool library that is shared and acts like a windows forms library, no behaviors for controlling adorner drag etc.

WPF Get Image inside drawing

I'm using an Image control inside a simple canvas and I allow final user to draw some line (free hand) through Line wpf object.
When user ends his draw I would be able to get the image inside the design (such as a crop image).
Any idea?

Drawing shapes, text and images with moving and scaling in WPF

I'm trying to draw simple map in WPF. I need to draw shapes, text and images. It also should be possible to use mouse to move around and zoom in and out.
Right now, I have combination of Canvas + Geometry + Transforms to draw shapes, but I don't know how to add text and images.
I already tried various combination of Canvas/Grid and Layout/Render transform. Biggest problem is adding text and images, because transformations are in geometries.
If i understand you right, you're currently putting Path objects (with transformed Geometries) into a Canvas. For adding text and images you could easily add TextBlock and Image objects to the same Canvas and apply your transformations to their RenderTransform property.
A completely different approach would be to use WPF low-level rendering, provided by the DrawingVisual class. You may start at WPF Graphics Rendering Overview.

How to draw shapes on top of Silverlight multiscaleimage?

There is a multiscale image with deepzoom image as a source. Now I need to allow users to draw poligons and lines on top of the multiscalimage in such a way that the shapes will follow drag and zoom to scale accordingly.
I tried to add a canvas in addition to the multiscaleimage but can't figure out how to make them stick to each other on zoom or drags.
If you have done any user shape drawing on top of deepzoom image, please share your methods.
Thanks,
Val
Have you checked the Silverlight 4 Puzzle demo?
http://johnpapa.net/silverlight/silverlight-4-html-puzzle-how-does-it-work/
You may be able to get some "inspiration" by inspecting this app.
Follow the link to download the source:
http://www.silverlight.net/community/samples/silverlight-4/html-puzzle/
I've done this before. Not sure if this is the preferred/optimal way, but you can add layers to your root deepzoom layer. (sorry, i forget the proper terminology).
In my case i had 4 sub layers, some of which were used to render lines and shapes, others were used to render entire maps that were loaded from a URI.

What is the best way in Silerlight to make areas of a large graphic clickable?

In a Silverlight application I have large images which have flow charts on them.
I need to handle the clicks on specific hotspots of the image where the flow chart boxes are.
Since the flow charts will always be different, the information of where the hotspots has to be dynamic, e.g. in a list of coordinates.
I've found article like this one but don't need the detail of e.g. the outline of countries but just simple rectangle and circle areas.
I've also found articles where they talk about overlaying an HTML image map over the silverlight application, but it has to be easier than this.
What is the best way to handle clicks on specific areas of an image in silverlight?
Place the Image and a Canvas in a Grid so that the Canvas overlays the Image.
Add shapes of appropriate sizes and placed as needed to the canvas. All shapes will a transparent fill and no border, hence the user only sees the Image. On the Canvas MouseDown (or Up events) use OriginalSource to determine which shape generated the click. Use the Tag property of each shape to associate it with some object that represents the flowchart element being mapped.
I found an easy way to do this without a canvas:
How to get the coordinates of an image mouse click in the event handler?

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