asgardius/virtualx-engine
1
0
Fork 0
Code Issues Pull requests Projects Releases 1 Packages Wiki Activity Actions

C#: Add Skew to Transform2D and fix InterpolateWith

Browse source 
- Add `Skew` property to `Transform2D`.
- Fix `InterpolateWith` in `Transform2D` to support skewed transforms.
This commit is contained in:
Raul Santos 2023-01-15 04:05:32 +01:00
parent d01ac9c736
commit 2ef9e2933a
No known key found for this signature in database
GPG key ID: B532473AE3A803E4
1 changed files with 19 additions and 42 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

61
modules/mono/glue/GodotSharp/GodotSharp/Core/Transform2D.cs
View file

@ -49,6 +49,18 @@ namespace Godot
}
}
/// <summary>
/// Returns the transform's skew (in radians).
/// </summary>
public readonly real_t Skew
{
get
{
real_t detSign = Mathf.Sign(BasisDeterminant());
return Mathf.Acos(X.Normalized().Dot(detSign * Y.Normalized())) - Mathf.Pi * 0.5f;
}
}
/// <summary>
/// Access whole columns in the form of <see cref="Vector2"/>.
/// The third column is the <see cref="Origin"/> vector.
@ -190,48 +202,13 @@ namespace Godot
/// <returns>The interpolated transform.</returns>
public readonly Transform2D InterpolateWith(Transform2D transform, real_t weight)
{
real_t r1 = Rotation;
real_t r2 = transform.Rotation;
Vector2 s1 = Scale;
Vector2 s2 = transform.Scale;
// Slerp rotation
(real_t sin1, real_t cos1) = Mathf.SinCos(r1);
(real_t sin2, real_t cos2) = Mathf.SinCos(r2);
var v1 = new Vector2(cos1, sin1);
var v2 = new Vector2(cos2, sin2);
real_t dot = v1.Dot(v2);
dot = Mathf.Clamp(dot, -1.0f, 1.0f);
Vector2 v;
if (dot > 0.9995f)
{
// Linearly interpolate to avoid numerical precision issues
v = v1.Lerp(v2, weight).Normalized();
}
else
{
real_t angle = weight * Mathf.Acos(dot);
Vector2 v3 = (v2 - (v1 * dot)).Normalized();
(real_t sine, real_t cos) = Mathf.SinCos(angle);
v = (v1 * sine) + (v3 * cos);
}
// Extract parameters
Vector2 p1 = Origin;
Vector2 p2 = transform.Origin;
// Construct matrix
var res = new Transform2D(Mathf.Atan2(v.Y, v.X), p1.Lerp(p2, weight));
Vector2 scale = s1.Lerp(s2, weight);
res.X *= scale;
res.Y *= scale;
return res;
return new Transform2D
(
Mathf.LerpAngle(Rotation, transform.Rotation, weight),
Scale.Lerp(transform.Scale, weight),
Mathf.LerpAngle(Skew, transform.Skew, weight),
Origin.Lerp(transform.Origin, weight)
);
}
/// <summary>