Wt

Hi!

First, thanks for the good work on Wt! I have used it for building a basic web-based image search engine and found it very useful.

I am now looking into deeper usage of Wt, particularly in the DBo module. However, I found myself stuck with what may looks like a basic issue:

Assume that I want to store some object instances in a a DB, for example image histograms. Let's say that there is a class Histogram that computes and stores the values of the histogram (typically as an array of integers). However, I can have several kinds of histograms, depending on the color space in which the image is encoded. Typically, pixels have Red,Gree,Blue values, but the image can be transformed into a gray level image, where each pixel is associated with only 1 gray level value. The same code can be used in the histogram class, but the values computed and stored in the objects will depend on the color space, which is a parameter of my histogram class.

Now, I would like to store in different tables the RGB histograms and the Gray Lavel histograms. I dont see how this is possible with the session.mapClass function since T is template parameter while I rely on instanciated parameters to be able to differentiate the different types of histograms. Is there a way to do so? This is an issue I frequently come into, having the same code (same class) computing very different informations depending on the parameters of the algorithm, and I want to be able to store and retrieve the computed values according to a fixed set of parameters.

Hope my question is clear enough and that I can get some help!

Thanks again

R.V.