Problem with texture coordinates

[Aerilius]

Hello,
I'm trying to match a texture to the corner points of a quadrangle (no rectangle). Somehow the texture does not display immediately how I expect it (image 1).

When I right click -> position texture and cancel without moving the texture position, it suddenly displays correctly (image 2). There is something that I miss and I don't know what. Can someone help me?

c=[Point3d(0, 0, 0), Point3d(6.13575e+006, -2.05147e+006, 0), Point3d(4.22755e+006, 450980, 0), Point3d(-295726, 698978, 0)]
face=entities.add_face(*c).reverse!
# create material
m=materials.add "material1"
m.texture=imghref
face.material=m

# I want to match the texture coordinates to the corners of the face
# c[i] are the corner points of the face
pt_array = []
pt_array[0] = c[0]
pt_array[1] = Geom;;Point3d.new(0,0,0)
pt_array[2] = c[1]
pt_array[3] = Geom;;Point3d.new(1,0,0)
pt_array[4] = c[2]
pt_array[5] = Geom;;Point3d.new(1,1,0)
pt_array[6] = c[3]
pt_array[7] = Geom;;Point3d.new(0,1,0)
on_front = true
face.position_material m, pt_array, on_front

[thomthom]

I'm in a rush - so just a quick drive-by-post:
I don't have time to analyse your code right now - but I have some code that does what you want to do in UV Toolkit: http://forums.sketchucation.com/viewtopic.php?f=323&t=18992&p=155759
"Fit Texture to Quadface"

[Aerilius]

Thanks! I found the essential step in your code ( TT::Face.corners( e )).
It seems to work for me just fine when I change the order of the points to (the array c contains always exactly 4 points in the same order).

pt_array[0] = c[0]
pt_array[1] = Geom;;Point3d.new(0,0,0)
pt_array[2] = c[1]
pt_array[3] = Geom;;Point3d.new(1,0,0)
pt_array[4] = c[2]
pt_array[5] = Geom;;Point3d.new(1,1,0)
pt_array[6] = c[3]
pt_array[7] = Geom;;Point3d.new(0,1,0)