some gap filling..
As far as Tom told me, PDP operates using a system of types. For each named type of data there is a way packets are constructed and a set of object classes willing to accept them.
jep. that's how it works now. it will stay like that in the upcoming release. the reason it's typed is performance. next release should have some more flexibility wrt to polymorphy and mixing several types.
AFAIK, PDP has linear algebra functions, and actually is better at it than GridFlow, but those functions are separate from the picture processing, so for example in PDP you can't implement your own hue-shift
yet :)
effect by multiplying a picture by a matrix, whereas I'm doing exactly that in GridFlow. But maybe Tom can give you the exact details, as I am but a beginner with PDP.
the linear algebra functions in pdp are indeed completely separate from the image processing. the only connection being a matrix<->image type conversion. the linear algebra stuff is there to support 3dp, but it's not even connected to 3dp right now, so not really usable. you can use it to make some nice pictures, but thats about all. matrix and 3dp will stay experimental until the new image processing engine is in place.