On Fri, 28 Oct 2022 16:23:10 GMT, Kevin Rushforth <k...@openjdk.org> wrote:
>> No, what I meant is this:
>>
>> System.out.println("(int)-1.9999=" + (int)-1.9999 + "
>> (int)Math.round(-1.9999)=" + (int)(Math.round(-1.9999)));
>> prints
>> (int)-1.9999=-1 (int)Math.round(-1.9999)=-2
>>
>>
>> i.e. typecast to int is equivalent to Math.ceil for negative values and
>> Math.floor for positive. We probably should use Math.round().
>>
>> This code should be better tested on Windows with
>> a) second monitor positioned to the left of the main one, making its
>> coordinates negative
>> b) using fractional HiDPI scaling which is only available on Windows it seems
>>
>> And yes, I did not see Dimension2D - we probably should remove confusion and
>> use Point2D (why does it have more overhead?)
>
> Depending on the desired result, we use `Math.floor`, `Math.ceil`, or
> `Math.round` -- it's important to pick the right one.
>
> But yes, using one of those is (almost always) better than just casting to
> `(int)` if the value might be negative.
I think in this case, `Math.floor()` is what you want. I wonder, though,
whether it needs to be converted to an `int` at all? It looks like everywhere
it is used, it can be kept as a double.
Btw, I almost wrote a comment asking a question as to whether you were using
the values of x, y, width, and height correctly, because I got confused that
you were using a Dimension to hold an x,y point. If you decide to keep it as a
Dimension, I might suggest adding a clarifying comment.
-------------
PR: https://git.openjdk.org/jfx/pull/924
