Function directx_math::XMVectorBaryCentric[−][src]

pub fn XMVectorBaryCentric(
    Position0: FXMVECTOR, 
    Position1: FXMVECTOR, 
    Position2: FXMVECTOR, 
    f: f32, 
    g: f32
) -> XMVECTOR

Returns a point in Barycentric coordinates, using the specified position vectors.

Parameters

Position0 First position.

Position1 Second position.

Position2 Third position.

f Weighting factor. See the remarks.

g Weighting factor. See the remarks.

Return value

Returns the Barycentric coordinates.

Remarks

This function provides a way to understand points in and around a triangle, independent of where the triangle is located. This function returns the resulting point by using the following equation:

Position0 + f * (Position1 - Position0) + g * (Position2 - Position0)

Any point in the plane Position0Position1Position2 can be represented by the Barycentric coordinate (f, g), where f controls how much Position1 gets weighted into the result, and g controls how much Position2 gets weighted into the result. Lastly, 1-f-g controls how much Position0 gets weighted into the result.

Note the following relations.

  • If (f>=0 && g>=0 && 1-f-g>=0), the point is inside the triangle Position0Position1Position2.
  • If (f==0 && g>=0 && 1-f-g>=0), the point is on the line Position0Position2.
  • If (f>=0 && g==0 && 1-f-g>=0), the point is on the line Position0Position1.
  • If (f>=0 && g>=0 && 1-f-g==0), the point is on the line Position1Position2.

Barycentric coordinates are a form of general coordinates. In this context, using Barycentric coordinates represents a change in coordinate systems. What holds true for Cartesian coordinates holds true for Barycentric coordinates.

Reference

https://docs.microsoft.com/en-us/windows/win32/api/directxmath/nf-directxmath-XMVectorBaryCentric