mirror of
https://github.com/ClassiCube/ClassiCube.git
synced 2025-01-24 18:13:15 -05:00
38 lines
No EOL
1.6 KiB
C#
38 lines
No EOL
1.6 KiB
C#
using System;
|
|
using System.Collections.Generic;
|
|
using OpenTK;
|
|
|
|
namespace ClassicalSharp.Selections {
|
|
|
|
internal class SelectionBoxComparer : IComparer<SelectionBox> {
|
|
|
|
public int Compare( SelectionBox a, SelectionBox b ) {
|
|
// Reversed comparison order because we need to render back to front for alpha blending.
|
|
return a.MinDist == b.MinDist ? b.MaxDist.CompareTo( a.MaxDist )
|
|
: b.MinDist.CompareTo( a.MinDist );
|
|
}
|
|
|
|
internal void Intersect( SelectionBox box, Vector3 origin ) {
|
|
Vector3I min = box.Min, max = box.Max;
|
|
float closest = float.PositiveInfinity, furthest = float.NegativeInfinity;
|
|
// Bottom corners
|
|
UpdateDist( origin, min.X, min.Y, min.Z, ref closest, ref furthest );
|
|
UpdateDist( origin, max.X, min.Y, min.Z, ref closest, ref furthest );
|
|
UpdateDist( origin, max.X, min.Y, max.Z, ref closest, ref furthest );
|
|
UpdateDist( origin, min.X, min.Y, max.Z, ref closest, ref furthest );
|
|
// Top corners
|
|
UpdateDist( origin, min.X, max.Y, min.Z, ref closest, ref furthest );
|
|
UpdateDist( origin, max.X, max.Y, min.Z, ref closest, ref furthest );
|
|
UpdateDist( origin, max.X, max.Y, max.Z, ref closest, ref furthest );
|
|
UpdateDist( origin, min.X, max.Y, max.Z, ref closest, ref furthest );
|
|
box.MinDist = closest; box.MaxDist = furthest;
|
|
}
|
|
|
|
static void UpdateDist( Vector3 p, float x2, float y2, float z2,
|
|
ref float closest, ref float furthest ) {
|
|
float dist = Utils.DistanceSquared( p.X, p.Y, p.Z, x2, y2, z2 );
|
|
if( dist < closest ) closest = dist;
|
|
if( dist > furthest ) furthest = dist;
|
|
}
|
|
}
|
|
} |