Multiple formats, too
Coffee is over (or, in my case, break for tea), and now Ilya Zavyalov is telling us about large data and multiple format for Teigha Cloud.
To handle large drawings on the cloud, some rendering is done on the server side and some on the client side (ie, in the Web browser). The server must, however, must have access to view accelerators, which is not common and so expensive. For rendering to happen on the client, however, it must be powerful enough, especially for large drawings.
There are, fortunately, techniques to make this easier:
- Graphic format -- it is a database, and can be compressed
- Data streaming -- used by all cloud applications; allows us to start viewing and editing the file before it is fully loaded
- Partial loading -- load only part of the drawing, such as a zoomed in area, or area being edited; takes up less memory
- Level of Detail -- not sending all geometric information about each element, which reduces the number of MB that need to be transmitted
Here is a view of the format used by Teigha for cloud graphics:
Teigha Cloud supports the following formats (plus one more to be announced later today):
Mark Up Editing
To add mark up editing to the cloud, they added polylines, circles, text, undo, and erase. From these basics, other markup tools can be added, such as leaders.
Q: Where is the markup data stored?
A: In the DWG database.
Q: Which libraries are used for the cloud?
A: It is all our own libraries.