maybe port webrad (http://sourceforge.net/projects/webrad) to lazarus is a good start point.
2007/8/20, Sebastian Günther <[EMAIL PROTECTED]>: > > Michael Van Canneyt schrieb: > > > >> Please explain why that isn't possible to do a conversion of such an > app using > >> Javascript ? > > > > Are you going to compile the pascal to javascript ? > > Hello *, > > as I already wrote Michael in private I'm thinking about developing a > web widgetset for LCL as well. > > My current considerations are these: > > The application of course gets compiled as usual and runs on the server. > There is only one major issue: A web application must be prepared for > multithreading, as there is one instance of the 'main form' per user > access (or session). But, if properly written (storing data in the main > class, and not using global variables), this is not a real problem. > > JavaScript will only be used for drawing and content creation, and for > event propagation of course. Communication using AJAX or JSON, but using > the synchronous version of HTTPRequest (remember that most desktop > widget toolkits are working synchronous as well, for good reason). For > example, the canvas: Drawing commands will be buffered, and as soon as > execution returned to the main loop, this command buffer will be send to > the JavaScript client. (Of course there might be special cases like > painting in a canvas and immediately reading data back from the > framebuffer. In this case it might be necesseray to emulate the whole > painting on the server using a memory image.) > > Really all kinds of widgets can be emulated using JavaScript and DHTML. > > This approach surely would work quite well -- but it would be quite > slow, dependent on the exact application. > Btw, what we could do is to support Microsofts Silverlight; if this > plugin is installed, create all widgets using Silverlight, where you can > use _all_ widgets which .NET's Windows.Forms support. > But back to JS/DHTML. To improve performance, I see only one way, the > way that Google's Web Toolkit is going: Analyze the source code and try > to convert single methods to JavaScript wherever possible, using some > kind of JS version of the FPC RTL. By time, this library would get > bigger and bigger, improving the performance step by step. But of course > the source analyzer has to be extremely careful about keeping the > application state in sync between client and server. > > > Any comments? :-) > > > - Sebastian > > _________________________________________________________________ > To unsubscribe: mail [EMAIL PROTECTED] with > "unsubscribe" as the Subject > archives at http://www.lazarus.freepascal.org/mailarchives > -- Carlos Germán Tejero
