108 lines
3.7 KiB
C#
108 lines
3.7 KiB
C#
namespace UnityEngine.U2D.Animation.TriangleNet
|
|
.Tools
|
|
{
|
|
using Animation.TriangleNet.Geometry;
|
|
|
|
internal static class Interpolation
|
|
{
|
|
#if USE_ATTRIBS
|
|
/// <summary>
|
|
/// Linear interpolation of vertex attributes.
|
|
/// </summary>
|
|
/// <param name="vertex">The interpolation vertex.</param>
|
|
/// <param name="triangle">The triangle containing the vertex.</param>
|
|
/// <param name="n">The number of vertex attributes.</param>
|
|
/// <remarks>
|
|
/// The vertex is expected to lie inside the triangle.
|
|
/// </remarks>
|
|
internal static void InterpolateAttributes(Vertex vertex, ITriangle triangle, int n)
|
|
{
|
|
Vertex org = triangle.GetVertex(0);
|
|
Vertex dest = triangle.GetVertex(1);
|
|
Vertex apex = triangle.GetVertex(2);
|
|
|
|
double xdo, ydo, xao, yao;
|
|
double denominator;
|
|
double dx, dy;
|
|
double xi, eta;
|
|
|
|
// Compute the circumcenter of the triangle.
|
|
xdo = dest.x - org.x;
|
|
ydo = dest.y - org.y;
|
|
xao = apex.x - org.x;
|
|
yao = apex.y - org.y;
|
|
|
|
denominator = 0.5 / (xdo * yao - xao * ydo);
|
|
|
|
//dx = (yao * dodist - ydo * aodist) * denominator;
|
|
//dy = (xdo * aodist - xao * dodist) * denominator;
|
|
|
|
dx = vertex.x - org.x;
|
|
dy = vertex.y - org.y;
|
|
|
|
// To interpolate vertex attributes for the new vertex, define a
|
|
// coordinate system with a xi-axis directed from the triangle's
|
|
// origin to its destination, and an eta-axis, directed from its
|
|
// origin to its apex.
|
|
xi = (yao * dx - xao * dy) * (2.0 * denominator);
|
|
eta = (xdo * dy - ydo * dx) * (2.0 * denominator);
|
|
|
|
for (int i = 0; i < n; i++)
|
|
{
|
|
// Interpolate the vertex attributes.
|
|
vertex.attributes[i] = org.attributes[i]
|
|
+ xi * (dest.attributes[i] - org.attributes[i])
|
|
+ eta * (apex.attributes[i] - org.attributes[i]);
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
#if USE_Z
|
|
/// <summary>
|
|
/// Linear interpolation of a scalar value.
|
|
/// </summary>
|
|
/// <param name="p">The interpolation point.</param>
|
|
/// <param name="triangle">The triangle containing the point.</param>
|
|
/// <remarks>
|
|
/// The point is expected to lie inside the triangle.
|
|
/// </remarks>
|
|
internal static void InterpolateZ(Point p, ITriangle triangle)
|
|
{
|
|
Vertex org = triangle.GetVertex(0);
|
|
Vertex dest = triangle.GetVertex(1);
|
|
Vertex apex = triangle.GetVertex(2);
|
|
|
|
double xdo, ydo, xao, yao;
|
|
double denominator;
|
|
double dx, dy;
|
|
double xi, eta;
|
|
|
|
// Compute the circumcenter of the triangle.
|
|
xdo = dest.x - org.x;
|
|
ydo = dest.y - org.y;
|
|
xao = apex.x - org.x;
|
|
yao = apex.y - org.y;
|
|
|
|
denominator = 0.5 / (xdo * yao - xao * ydo);
|
|
|
|
//dx = (yao * dodist - ydo * aodist) * denominator;
|
|
//dy = (xdo * aodist - xao * dodist) * denominator;
|
|
|
|
dx = p.x - org.x;
|
|
dy = p.y - org.y;
|
|
|
|
// To interpolate z value for the given point inserted, define a
|
|
// coordinate system with a xi-axis, directed from the triangle's
|
|
// origin to its destination, and an eta-axis, directed from its
|
|
// origin to its apex.
|
|
xi = (yao * dx - xao * dy) * (2.0 * denominator);
|
|
eta = (xdo * dy - ydo * dx) * (2.0 * denominator);
|
|
|
|
p.z = org.z + xi * (dest.z - org.z) + eta * (apex.z - org.z);
|
|
}
|
|
|
|
#endif
|
|
}
|
|
}
|