Half-baked API (Camera position)

Kevin Rushforth kevin.rushforth at oracle.com
Wed Oct 16 07:57:07 PDT 2013

Regarding #2, I'm OK with an exception being thrown.

Regarding #1, do you think moving the clip planes to PerspectiveCamera 
(rather than in the base class) be better for FX 8? We can compatibly 
move it up to a superclass in a future release. Or would this be too 

-- Kevin

Richard Bair wrote:
> My quick vote would be throwing the exception, but is like to hear from Steve and Kevin. 
>> On Oct 16, 2013, at 1:04 AM, Pavel Safrata <pavel.safrata at oracle.com> wrote:
>> Hello,
>> it looks like we can't help releasing a not-fully-baked piece of API with FX8. We've added bunch of new APIs for 3D and did our best to make them work well. Unfortunately, there's been not enough time&priority to fine-tune their behavior in 2D world. Right now I'm concerned about camera position in scene. It is inherent in the 3D perspective camera that it has its specific position in world, but the 2D parallel camera as we have it projects everything to the XY plane basically by ignoring the Z coordinate, so the camera position doesn't matter all that much. However, some of the newly added APIs depend on it:
>> 1. Near/far clip on camera. This obviously cannot work without knowing where the camera is. Right now the parallel camera does no clipping though, so I guess we are OK to go with it as a "known limitation".
>> 2. PickResult on events which reports "intersectedDistance" between the camera and the picked point. This is worse because we can't just "not support" it - there will be some value and once somebody uses it we'll have a backward compatibility issue. The state right now is that the camera is (tentatively, by my arbitrary decision) at [0, 0, -1] and reports distances from there (note that as the camera renders everything, for nodes "in front of Z=-1" it reports negative distances). This may change when the camera position is properly discussed and specified.
>> Note that this post is *not* meant to discuss the camera position. Even if we could find the answer quickly (which I doubt), it's most probably too late to apply the change for FX8.
>> So finally here is my question: do you think it's OK to solve this by keeping the current behavior and documenting the "intersectedDistance" in a way that for parallel camera the numbers are unspecified and subject to change in future versions? Or would you prefer something more drastic like throwing an UnsupportedOperationException (losing the possibility to compare the distances)?
>> Thanks,
>> Pavel

More information about the openjfx-dev mailing list