Code My Own Pan, Zoom and Area Zoom?
Posted: Mon May 12, 2014 3:57 am
I am trying to find a fast document viewer that will work in ASP across all browsers and multiple document types, mainly Office and PDF. In separate communications, you have explained that the gdviewer is ActiveX and will only work in iExplorer and that you may develop an HTML viewer at some point as a separate product, but not yet.
I have experimented with some other HTML viewers and they are not very fast (and some are too expensive for my budget). I have found software that will convert Office files to either image or PDF, so I have that part covered. I also have software that will extract the pages from PDF's to create JPG's so that part is covered. So, now I am wondering if there is a way to use gdPicture to manipulate images to essentially create my own viewer that only uses image files. I see plenty of ways to handle zooming and resolution, but I do not see an obvious way to handle panning and rectangle-area zooming like it is done in Acrobat to the gdviewer. I guess if that were easy, you would already have an example, but I thought I would ask anyway, especially if there are any functions in the newer versions (8, 9 or 10) that might help me accomplish my goal.
I have noticed that many HTML viewers use the method of extracting a 100% resolution thumbnail on the fly. To zoom double, they simple extract a zoomed image and display that -- but that is not very fast if you want to smoothly zoom in single percentage increments or zoom from the mouse wheel, unless images of preset zooms were stored in a database. Of course users can simply zoom the browser, but that doesn't give the same effect that you get within Acrobat reader. Maybe this functionality isn't practical in a browser with image manipulation, but I thought maybe with enough code and simplified requirements, it could be done and was worth asking if you had any examples or ideas.
I have an older version of gdPicture. I wondered if any of the newer versions had new features that would allow me to simulate a zooming effect and area zoom, but when I went to the documentation page to research this myself, every link to the documentation gave me an error, so also please let me know how I can read the newest documentation.
When I click on the documentation button to go to this URL: https://www.gdpicture.com/gdpicturedoc.zip
I get an Error 404 - Page Not Found.
Thanks!
I have experimented with some other HTML viewers and they are not very fast (and some are too expensive for my budget). I have found software that will convert Office files to either image or PDF, so I have that part covered. I also have software that will extract the pages from PDF's to create JPG's so that part is covered. So, now I am wondering if there is a way to use gdPicture to manipulate images to essentially create my own viewer that only uses image files. I see plenty of ways to handle zooming and resolution, but I do not see an obvious way to handle panning and rectangle-area zooming like it is done in Acrobat to the gdviewer. I guess if that were easy, you would already have an example, but I thought I would ask anyway, especially if there are any functions in the newer versions (8, 9 or 10) that might help me accomplish my goal.
I have noticed that many HTML viewers use the method of extracting a 100% resolution thumbnail on the fly. To zoom double, they simple extract a zoomed image and display that -- but that is not very fast if you want to smoothly zoom in single percentage increments or zoom from the mouse wheel, unless images of preset zooms were stored in a database. Of course users can simply zoom the browser, but that doesn't give the same effect that you get within Acrobat reader. Maybe this functionality isn't practical in a browser with image manipulation, but I thought maybe with enough code and simplified requirements, it could be done and was worth asking if you had any examples or ideas.
I have an older version of gdPicture. I wondered if any of the newer versions had new features that would allow me to simulate a zooming effect and area zoom, but when I went to the documentation page to research this myself, every link to the documentation gave me an error, so also please let me know how I can read the newest documentation.
When I click on the documentation button to go to this URL: https://www.gdpicture.com/gdpicturedoc.zip
I get an Error 404 - Page Not Found.
Thanks!