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Better support for GIS docs in Canvas Draw (without full implementation of GIS)

Canvas Draw is already a pretty good viewer for GIS documents. If one uses a UTM projection, then the XY coords in Canvas Draw are the UTM eastings and northings. Without a huge amount of work (i.e., implementing full Windows Canvas GIS functionality) Canvas Draw could be made into an excellent viewer for Canvas GIS documents. Here's what we users would need for minimal increased functionality:


1. Preserve object properties on opening in CD and give us an object properties palette to view those properties. 


2. Preserve enough projection and datum information that we can see the Latitude and Longitude under the pointer as well as the XY coordinates.


3. Save as .CVX, preserving the GIS attributes so that we can go round trip between Canvas Draw and Canvas GIS without losing any data (if I remember correctly, before the introduction of the .CVD format, this was already possible). If we lose text formatting because of the different text models, that's not a huge price to pay.


For further utility we would need


4. Selection and visualization by property (This would be useful even without GIS info).


5. Image warping to coordinates (including Lat-Long) and point to point image warping.


6. Create Scale bars and graticules, and choosing reference point.


Several of these features -- e.g., image warp, object properties with visualization and selection -- are extremely useful even for people who aren't interested in GIS. For example, point to point image warp for stitching photos together. 


These features would help to distinguish Canvas Draw in an increasingly crowded field on the Mac. Those of us who need GIS would still need to create the document in the Windows version of Canvas GIS but, once the basic document was assembled and projected on the Windows side, we could do our editing and visualization in Canvas Draw



From what I've gathered in past posts by ACD, Canvas Draw will not have .CVX export. Canvas for PC is being completely rewritten and as far as I know, will be compatible with .CVD. I also wouldn't be surprised if Canvas Draw will eventually include GIS.

I hope it does have full GIS compatibility one day but, in the meantime, what I have suggested above is a strategy for a phased implementation of the GIS functionality with the first step requiring minimal additional programming effort on their part. 


For example, they already have the algorithm for calculating Latitude-Longitude based on projection and datum and implementing that requires no interface changes at all. The object properties palette is a single palette which would require some, but not a great deal of, effort. Image warping would be a largely unique to Canvas Draw feature that would be very useful in other contexts as well. Scale bars require one additional Palette and the graphic commands to draw the scale (another feature that could be unique to CD and is useful for all sorts of technical drawing, not just GIS).


This strategy avoids them having to deal with implementing the zillion different projections and datums in Canvas GIS as well as all the code to switch between those. It also avoids having to implement the multitude of different GIS input and output formats some of which may be based on libraries that are unique to the Windows side. They could use one format, .cvx, to allow those of us who need to output in a different GIS format to take our modified document, go back to the Windows side, and output it there.


Coincidently, it also keeps those of us who need GIS capabilities buying two versions of Canvas, Draw for the Mac and Canvas GIS for Windows. I can't believe that I just wrote that as I really, really want Canvas GIS on the Mac but, if it gets us part of the way there it is an improvement.

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