From: Andrea A. <and...@al...> - 2004-05-20 14:04:17
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Martin Desruisseaux wrote: > Andrea Aime a écrit : > >> This would also mean that we need some modification to the way styles >> are handled, because every geometry in a group could have a different >> style... > > > Maybe, but at a very first look I don't think so... PointArray is at a > lower level than Geometries (i.e. a Geometry is made of PointArray), This is the very problem > so: > > - PointArray has no knowledge at all about Styles; this is handled at a > higher level (Geometry). We can see PointArray as an array of type > float[], nothing else. Except that the real backing store (float[], > double[], JTS's CoordinatePoint[], ZIP file, whatever) is abstracted. > > - Many Geometry (possibily with different styles) share the same > PointArray. This is already implemented exactly that way in J2D > renderer. This means that if a PointArray load data, all geometries > using that PointArray would have the data loaded, no matter which > style they use. > > Maybe I'm missing something... But if I'm understanding right, it seems > to me that no changes would be required to the way we handle Style, > since the work would be done at a level below that. It would fit with > current architecture. It won't in my opinion... oh, maybe I see what you mean. Each geometry will see a point array. Point arrays of nearby geometries are grouped togheter. When you draw a geometry the point array will fetch its data from the group, which in turn will lazy load data from the database... it may be easier to implement, but seems to be quite involved to me... Best regards Andrea Aime |