Ok, then please consider the GraphicsContext request that I’ve made.  It simply 
enables you to get the Path from the context without exposing com classes at 
all.  I have other workarounds where I have to maintain a path as I’m drawing 
in the canvas or I have to do hit testing on a non vector image to determine 
the path but these are way more expensive than simply creating a Path object 
from the Path2D that is already in the GraphicContext.  That path can be used 
in drag and drop scenarios, fast secondary rendering under heavy gc use, edge 
tracing, and the list goes on.

The same is true for the Shape class.  I’d like to request that the following 
be added to Shape:
public Path getPath() {
    return Shape.createFromGeomShape(getTransformedArea());
}

That’s it.  The underlying methods are there but the public api doesn’t expose 
them.  This gives you a vector outline of the Shape as Path.l on demand, not 
stored.

There are expensive workarounds for performing these tasks and I spent a long 
time trying... until I discovers the private apis already had the capability 
but simply did. It expose it.

I’d these are not supported, I’ll have to stick with reflection,  bytebuddy, or 
forking - non of which will be easily maintained or portable.

Ps I will post additional concerns over time.  The next one likely has to do 
with the mismatch between javafx canvas (gc) and other canvases such as svg, 
html2.  I think there is private api that would help in this case.

> On May 8, 2020, at 2:41 PM, Kevin Rushforth <kevin.rushfo...@oracle.com> 
> wrote:
> 
> Since Canvas is an immediate mode graphics API, I presume you are interested 
> in the most recent drawing primitive? (we don't keep the composite shape for 
> all drawing primitives -- that would be both too expensive and not really 
> appropriate). How would you expect current rendering attributes (e.g., 
> transforms) to affect the results? These are all questions that need to be 
> addressed.
> 
> As for the bigger picture, we intentionally have a separate render graph with 
> "peers" for each node, although some of the duplication of classes is 
> historical (we used to have a looser decoupling before Prism became the only 
> backend). Unless there is a compelling need, we are unlikely to consider 
> changing this in the general case, but perhaps could look at specific cases 
> if it made sense. This is a separate issue, though, from public API and the 
> two shouldn't be conflated.
> 
> Btw, JavaFX has been fully open-sourced since 2013, although the design of 
> Prism predates that.
> 
> -- Kevin
> 
> 
>> On 5/8/2020 10:43 AM, jfx user2 wrote:
>> Kevin, go easy please :0).  There is a need.
>> 
>> Access to the outline of the path in the canvas is great for edge following, 
>> node attachment points, animating around the non-rectangular border of 
>> what’s actually displayed, etc.
>> 
>> The other request that I haven’t posted yet is to do the same for Shape.   
>> I’ve tested both of these enhancements and it works as desired.  I’ll post 
>> the second request soon.
>> 
>> But back to the bigger picture.  The requests that I’m making are only 
>> additions to return a path from javafx not com.  But there are other cases 
>> where geometry and convenience methods in com would be beneficial to the 
>> public api.  It also seems odd that there are two layers to begin with...  
>> parallel apis often result in too much object creation or cpu overhead 
>> translating between them.  I’ll be more specific about these cases over 
>> time.   Part of my intention is to spark a discussion about the design since 
>> previously this was relatively closed source.
>> 
>>>> On May 8, 2020, at 1:12 PM, Kevin Rushforth <kevin.rushfo...@oracle.com> 
>>>> wrote:
>>> 
>>> While there is no plan to "open up" more of com.sun.javafx (and that isn't 
>>> really the right way to look at it), if you have a proposed enhancement to 
>>> the existing public javafx.* classes we could discuss it.
>>> 
>>> As for your specific example, can you say more about what your use case is? 
>>> The GraphicsContext object is a drawing context for a Canvas node, so it is 
>>> not a natural place to put an API that computes or returns a path. I get 
>>> the sense that you are looking at the existing internal implementation 
>>> classes and saying "how can I get access to some information that might be 
>>> useful to my application" rather than describing what your application is 
>>> trying to do. Once we understand what you are trying to do, we can discuss 
>>> whether the need is general enough to propose adding to the public API of 
>>> JavaFX and what form such a new API might take.
>>> 
>>> -- Kevin
>>> 
>>> 
>>>> On 5/8/2020 9:35 AM, jfx user2 wrote:
>>>> I am aware of this and that’s why I am asking.  There are useful private 
>>>> features in com.sun.javafx and I explained one of them in my message.  I 
>>>> have an additional related example but the larger question is if there is 
>>>> a plan to open more of com.sun.javafx to the public api, documentation 
>>>> surrounding this, or possibly a complete replacement?
>>>> 
>>>> Please consider the example I provided as a feature request.
>>>> 
>>>>>> On May 8, 2020, at 9:39 AM, Kevin Rushforth <kevin.rushfo...@oracle.com> 
>>>>>> wrote:
>>>>> Only javafx.* packages are part of the public API. Anything else, 
>>>>> including com.sun.javafx.*, is internal implementation details that an 
>>>>> application should never call.
>>>>> 
>>>>> -- Kevin
>>>>> 
>>>>> 
>>>>>> On 5/8/2020 12:38 AM, jfx user2 wrote:
>>>>>> Is there documentation around the packages (com.sun.javafx vs javafx) 
>>>>>> used
>>>>>> in JavaFX?
>>>>>> 
>>>>>> For example, why is there a com.sun.javafx.geom that isn't fully mirrored
>>>>>> in the javafx.scene.shape package?  Why are there missing features from
>>>>>> Graphics2D?
>>>>>> 
>>>>>> I have a specific example that prompted the question:
>>>>>> 
>>>>>> Consider the following classes:
>>>>>> 
>>>>>> javafx.scene.shape.Shape
>>>>>>     private static Path
>>>>>> createFromGeomShape(com.sunjavafx.geom.Shape geomShape)
>>>>>> 
>>>>>> javafx.scene.canvas.GraphicsContext
>>>>>>     Path2D path;
>>>>>> 
>>>>>> I want to write a line as follows:
>>>>>> Path path = Path.createFromGeomShape(gc.path);
>>>>>> b/c I want to inexpensively get the outline of the GraphicsContext.
>>>>>> 
>>>>>> However:
>>>>>> We can't access Path2D b/c it's in com.sun.javafx.geom which isn't 
>>>>>> exported
>>>>>> by the module.
>>>>>> We can't access Path.createFromGeomShape b/c it's private.
>>>>>> We can't access path in GraphicsContext b/c it's default and doesn't have
>>>>>> an accessor.
>>>>>> 
>>>>>> A possible solution is to add a new method:
>>>>>> javafx.scene.canvas.GraphicsContext
>>>>>> public Path getPath() {
>>>>>>     //implementation copied from
>>>>>> javafx.scene.shape.Shape.createFromGeomShape but use gc.path as the path
>>>>>> }
>>>>>> 
>>>>>> That would solve my immediate problem but raises the question... why is
>>>>>> com.sun.javafx hidden?  What's the architectural reason?  Is there any 
>>>>>> work
>>>>>> in progress that will impact this design?
>>>>>> 
>>>>>> PS my example is actually very important.  I currently use reflection and
>>>>>> module opens in the build to get the path but if the getPath method could
>>>>>> be added to GraphicsContext, that would be great.  For performance, it
>>>>>> would be even better to get the PathIterator directly instead of
>>>>>> translating into a javafx..Path but that is related to the bigger 
>>>>>> question.
> 

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