Adding Plane.Halfspace support

sandboxcoder · sandboxcoder · commit be428b2f2024 · 2023-07-05T19:53:57.000-05:00
diff --git a/RaysAndStuff/Plane.cs b/RaysAndStuff/Plane.cs
@@ -10,6 +10,13 @@ namespace RaysAndStuff
 {
     internal class Plane
     {
+        public enum Halfspace
+        {
+            Halfspace_BEHIND, //behind the plane
+            Halfspace_ON_PLANE,
+            Halfspace_FRONT, //in front of plane
+        };
+
         public Plane(Vector3 A, Vector3 B, Vector3 C)
         {
             Normal = Vector3.Cross((B - A), (C - A));  // NORMAL = AB X AC
@@ -49,6 +56,14 @@ public float DistanceTo(Vector3 P)
             return Vector3.Dot(Normal, P) + D;
 		}
 
+        public Halfspace ClassifyPoint(Vector3 P)
+        {
+            float d = DistanceTo(P);
+            if (d == 0) return Halfspace.Halfspace_ON_PLANE;
+            if (d > 0) return Halfspace.Halfspace_FRONT;
+            return Halfspace.Halfspace_BEHIND;
+        }
+
         public readonly Vector3 Normal; // Normalized vector perpendicular to the plane
         public readonly float D;  // Distance from a point to the plane.
     }
diff --git a/RaysAndStuff/Ray.cs b/RaysAndStuff/Ray.cs
@@ -4,12 +4,17 @@
 using System.Text;
 using System.Threading.Tasks;
 using System.Numerics;
+using System.Xml.Linq;
 
 namespace RaysAndStuff
 {
     internal struct Ray
     {
         public Vector3 Start;
         public Vector3 Dir;
+        public override string ToString()
+        {
+            return "Start:" + Start.ToString() + " Dir:" + Dir.ToString();
+        }
     }
 }
diff --git a/RaysAndStuff/ShootRays.cs b/RaysAndStuff/ShootRays.cs
@@ -21,6 +21,7 @@ public ShootRays()
             for(int r = 0; r < rays.Count; r++)
             {
                 Ray ray = rays[r];
+                Console.WriteLine($"Ray {r}: {ray}");
                 foreach (Plane plane in planes)
                 {
                     if (plane.RayIntersection(ray.Start, ray.Dir, ref t, ref hitPt))
@@ -29,10 +30,13 @@ public ShootRays()
                     }
                     else
                     {
-                        Console.WriteLine("Ray missed plane " + count);
+                        Console.WriteLine($"Ray {r} missed plane {count}");
                     }
                     float dist1 = plane.DistanceTo(ray.Start);
                     Console.WriteLine($"Plane: {count} distance: {dist1}");
+                    Plane.Halfspace halfspace = plane.ClassifyPoint(ray.Start);
+                    var text = halfspace.ToString();
+                    Console.WriteLine("Classification Ray.start: " + text);
                     count++;
                 }
             }

Original file line number	Diff line number	Diff line change
`@@ -10,6 +10,13 @@ namespace RaysAndStuff`
`10`	`10`	`{`
`11`	`11`	`internal class Plane`
`12`	`12`	`{`
	`13`	`+ public enum Halfspace`
	`14`	`+ {`
	`15`	`+ Halfspace_BEHIND, //behind the plane`
	`16`	`+ Halfspace_ON_PLANE,`
	`17`	`+ Halfspace_FRONT, //in front of plane`
	`18`	`+ };`
	`19`	`+`
`13`	`20`	`public Plane(Vector3 A, Vector3 B, Vector3 C)`
`14`	`21`	`{`
`15`	`22`	`Normal = Vector3.Cross((B - A), (C - A)); // NORMAL = AB X AC`
`@@ -49,6 +56,14 @@ public float DistanceTo(Vector3 P)`
`49`	`56`	`return Vector3.Dot(Normal, P) + D;`
`50`	`57`	`}`
`51`	`58`
	`59`	`+ public Halfspace ClassifyPoint(Vector3 P)`
	`60`	`+ {`
	`61`	`+ float d = DistanceTo(P);`
	`62`	`+ if (d == 0) return Halfspace.Halfspace_ON_PLANE;`
	`63`	`+ if (d > 0) return Halfspace.Halfspace_FRONT;`
	`64`	`+ return Halfspace.Halfspace_BEHIND;`
	`65`	`+ }`
	`66`	`+`
`52`	`67`	`public readonly Vector3 Normal; // Normalized vector perpendicular to the plane`
`53`	`68`	`public readonly float D; // Distance from a point to the plane.`
`54`	`69`	`}`
Original file line number	Diff line number	Diff line change
`@@ -4,12 +4,17 @@`
`4`	`4`	`using System.Text;`
`5`	`5`	`using System.Threading.Tasks;`
`6`	`6`	`using System.Numerics;`
	`7`	`+using System.Xml.Linq;`
`7`	`8`
`8`	`9`	`namespace RaysAndStuff`
`9`	`10`	`{`
`10`	`11`	`internal struct Ray`
`11`	`12`	`{`
`12`	`13`	`public Vector3 Start;`
`13`	`14`	`public Vector3 Dir;`
	`15`	`+ public override string ToString()`
	`16`	`+ {`
	`17`	`+ return "Start:" + Start.ToString() + " Dir:" + Dir.ToString();`
	`18`	`+ }`
`14`	`19`	`}`
`15`	`20`	`}`
Original file line number	Diff line number	Diff line change
`@@ -21,6 +21,7 @@ public ShootRays()`
`21`	`21`	`for(int r = 0; r < rays.Count; r++)`
`22`	`22`	`{`
`23`	`23`	`Ray ray = rays[r];`
	`24`	`+ Console.WriteLine($"Ray {r}: {ray}");`
`24`	`25`	`foreach (Plane plane in planes)`
`25`	`26`	`{`
`26`	`27`	`if (plane.RayIntersection(ray.Start, ray.Dir, ref t, ref hitPt))`
`@@ -29,10 +30,13 @@ public ShootRays()`
`29`	`30`	`}`
`30`	`31`	`else`
`31`	`32`	`{`
`32`		`- Console.WriteLine("Ray missed plane " + count);`
	`33`	`+ Console.WriteLine($"Ray {r} missed plane {count}");`
`33`	`34`	`}`
`34`	`35`	`float dist1 = plane.DistanceTo(ray.Start);`
`35`	`36`	`Console.WriteLine($"Plane: {count} distance: {dist1}");`
	`37`	`+ Plane.Halfspace halfspace = plane.ClassifyPoint(ray.Start);`
	`38`	`+ var text = halfspace.ToString();`
	`39`	`+ Console.WriteLine("Classification Ray.start: " + text);`
`36`	`40`	`count++;`
`37`	`41`	`}`
`38`	`42`	`}`