Transform point using localToSceneTransform

[Pavel Safrata]

Hi Kirill,

On 26.7.2012 10:10, Kirill.Prazdnikov wrote:
> On 26.07.2012 10:20, Pavel Safrata wrote:
>> Exactly, I think the point is that 'point' is not 'vector' regardless 
>> of what workarounds we introduce in method naming and documentation. 
>> Those methods would look really weird on Point. 
>
> Both are from the same R3 space, right ?

Right.

>
> And we can add them together :
>  Vector speed, position;
>   position += time * speed;
>
> I vote for Jim`s approach.

Does it make sense to add two points? I think it doesn't. So if we have 
Point and Vector, we need something like Point.add(Vector) or 
Point.shift(Vector). In Jim's approach we need Point.add(Point) with 
documentation stating that one of the points represents a point and the 
other one represents a vector. So what is the advantage?

>
> If a transform is { M3x3 + Translate }, them
>  - transformPoint (normal transform) would be { P*M3x3 + Translate }
>  - transformVector (delta transform) would be { P*M3x3 }

We already know that it is possible to represent both things by one 
class and move the distinction to method names and documentation. But 
please explain what is the advantage of it (except the obvious one of 
having lower class count).

Thanks,
Pavel

>
> -Kirill