I d like some feedbacks because I have the feeling I m gonna kotlinlang #announcements

val vert = Vec3() // Vert3 : Vec3t<Float>
vert.dot(fromTo) // error, none of the following functions can be called. Note that dot is dot(v: Vec3t<Number>)

I have to either change

dot

dot(v: Vec3t<Float>)

or create a new set of interfaces, where I have

Vec3tNumber

and

Vec3tFloat

and so on.. What do you think?

Andreas Sinz

03/16/2018, 11:03 AM

can you show us the code of your

interface Vec3t

elect

03/16/2018, 11:05 AM

https://github.com/kotlin-graphics/glm/blob/master/src/main/kotlin/glm_/vec3/Vec3t.kt

Andreas Sinz

03/16/2018, 11:12 AM

you've defined the generic type

but you are actually using

Number

everywhere. Is there a specific reason for that?

elect

03/16/2018, 11:23 AM

I need a generic type that shall be extended by the given implementation

what do you suggest?

Andreas Sinz

03/16/2018, 11:59 AM

i have the gut feeling that the whole Vec3 code can be simplified a lot if we make proper use of generics

should the API stay the same?

elect

03/16/2018, 12:03 PM

I like your gut feeling

what do you suggest

Andreas Sinz

03/16/2018, 12:34 PM

alright, lets start with the smaller ones: in every subclass you have operators like

plus

minus

etc

those functions just need a way to create a new instance of the subclass, then you can move many of the implementations into the base-class

abstract class Vec3t<T: Number>(...) {
    abstract protected inline fun createInstance(): Vec3t<T>

    operator fun plus(t: T) = plus(createInstance(), this, t, t, t)
    operator fun plus(t: Vec3t<T>) = plus(createInstance(), this, t.x, t.y, t.z)
}

all you have to do now is implement

createInstance

inside your

Vec3i

and you get plus operator for free

same for minus, times, div

elect

03/16/2018, 5:51 PM

clever hints

thanks dear

"inline" modifier is not allowed on virtual members

Andreas Sinz

03/16/2018, 6:09 PM

eh, remove that

inline

from

createInstance

, its not needed

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