Forward declaring an object won't work, I know, but it describes kind of what I
want.
In the code below I (at some time will) have in a library objects and procs for
defining and working on a half edge based polygon datastructure.
The user (I) can define properties for the connection elements in the mesh. Now
I'd like to somehowe fix the names of the objects and field names of Properties
on the library side of things. The problem is that they are depending on what
is done and can be wildly different. Is there a way to do this, kind of like
extending an object or forward declaring it?
Now for every new situation I every time have to write things like
`getVertexProperies()` instead of having it in the library side once.
Is there a way to achieve the result I look for?
import std/[options]
import vmath
# library defined
type
Vertex = object
point: int # unique, references mesh.vv[int], not null
hedge: int # an outgoing halfedge references conn.hedge[int],
not null
Face = object
hedge: int # incident halfedge references conn.hedge[int], not
null
HalfEdge = object
face: Option[int] # references conn.face[int],
vxi: int # references conn.vertex[int], not null
twin: int # references conn.hedge[int], not null
next: int # references conn.hedge[int], not null
prev: int # references conn.hedge[int], not null
Connect = object
vx: seq[Vertex]
face: seq[Face]
hedge: seq[HalfEdge]
Mesh* = object
vv*: seq[Vec3] # vertex vector seq
conn*: Connect
#==========
# user defined
type
# fields in xxProp can vary per use case
VxProp = object
normal: Vec3
uv: Vec2
# add a weight to vx for cloth animation
weight: float
FaceProp = object
normal: Vec3
# wind direction and force
wind: Vec4
HedgeProp = object
# stiffness of cloth
# in hedge as val varies for warp and weft
springconstant: seq[float]
Propertie = object
vx: seq[VxProp] # indices in sync with mesh.conn.vx
face: seq[FaceProp] # indices in sync with mesh.conn.face
hedge: seq[HedgeProp] # indices in sync with mesh.conn.hedge
MeshProp = object
mesh: Mesh
prop: Propertie
Run
