On Fri, May 21, 2010 at 2:25 PM, Henrik Rydberg <rydberg@xxxxxxxxxxx> wrote: > Ping Cheng wrote: >> On Fri, May 21, 2010 at 8:19 AM, Rafi Rubin <rafi@xxxxxxxxxxxxxx> wrote: > [...] >>> Ping: please confirm, are you actually talking about each finger simultaneously sending multiple positions? >> >> You are definitely on the right track. The fingers/touch objects can >> be represented two-dimensionally (x,y) instead of one-dimensionally >> (ABS_MT_TRACKING_ID). I think we can survive with the current MT_BLOB >> definition although some optimization would be helpful, especially for >> filtering. For the sake of Henrik great effort, I'd like to see his >> current patchset gets in the tree before we start another round of >> "suggestions". >> >> Thank you for asking. > > Regarding blobs, I confused myself yesterday. The original intention of the blob > id was in fact to be able to "paint" more generic contact forms. However, no > driver has come close to doing this yet, so it has gotten close to no attention. > Now, to address the question of how to communicate more elaborate contact forms, > it seems one can combine the two goals "one position per slot" and "multiple > positions per contact" by simply repeating the same tracking id for a set of > slots, like this: > > ABS_SLOT 0 > ABS_MT_TRACKING_ID 14 > ABS_MT_POSITION_X x[0] > ABS_MT_POSITION_Y y[0] > ABS_SLOT 1 > ABS_MT_TRACKING_ID 14 > ABS_MT_POSITION_X x[1] > ABS_MT_POSITION_Y y[1] > ABS_SLOT 2 > ABS_MT_TRACKING_ID 14 > ABS_MT_POSITION_X x[2] > ABS_MT_POSITION_Y y[2] This solution matches with my imagination more closely. Let's stay with it for now. I may come up with other suggestions once I have time to do real testing with the protocol. Thank you, Henrik, for your continuous effort. Ping -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
