<div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="HOEnZb"><div class="h5"> </div></div>Ok, so what I'm trying to do is to enable what people call "smooth scrolling" on an input level, meaning that scrolling is not based on discrete arbitrary "steps" but on a more fluid motion. These types of events makes most sense for certain types of step-less scroll wheels and touchpads and I'll try to explain why. When axis events are discrete steps, there is indeed little need to relate to any kind of coordinate space except knowing what is "up" and what is "down". A step can only be 1 or -1, thats it. This is how it traditionally works in X11 (except XI2 I think supports non-discrete axis events). If one wants to have axis events that more resemble smooth motions, such as the ones emitted by those step-less scroll wheels or touchpads, one needs to specify what the events actually mean, since they are no longer only limited to 1 and -1. To do this, if we specify an axis event to be a vector along an axis in a coordinate space identical to motion events, we can create axis events that relate to some measurement already known to both the compositor and client. A step-less scroll wheel would transform its scroll events to a motion vector measured in pixels and a touchpad would simply emit an axis event as it would emit a motion event when scrolling. A client could then read these events and can scroll its view by that amount of pixels specified by the value parameter. Jonas </blockquote></div> This makes it much clearer. I saw there was some discussion in IRC a few days ago too. Perhaps you could put the key points you've made here, in the protocol description. I guess the only thing is now, evdev needs fixing to emit the same expected format. Scott