getNormal implemented

Author: ben18mk

src/geometries/Cylinder.java

@@ -1,6 +1,8 @@
 package geometries;
 
 import primitives.*;
+
+import static primitives.Util.alignZero;
 import static primitives.Util.isZero;
 
 /**
@@ -38,7 +40,31 @@ public double getHeight() {
 
     @Override
     public Vector getNormal(Point point) {
-        return null;
+        Point bottomPoint = this.axisRay.getStartPoint();
+        Vector dir = this.axisRay.getDirection();
+
+        if (point.equals(bottomPoint)) // Check if the point is the bottom center point of the cylinder
+            return dir.scale(-1); // Returns the vector, opposite to the axis direction vector
+
+        if (point.equals(dir.scale(this.height))) // Check if the point is the top center point of the cylinder
+            return dir;
+
+        // Get the projection created by the axis vector and the vector between the top center point and the point
+        double projection = alignZero(dir.dotProduct(point.subtract(bottomPoint.add(dir.scale(this.height)))));
+        if (isZero(projection))
+            return dir; // If the projection is 0, it means that the point is on the top part of the cylinder
+
+        // Get the projection created by the axis vector and the vector between the bottom center point and the point
+        projection = alignZero(dir.dotProduct(point.subtract(bottomPoint)));
+        if (isZero(projection))
+            return dir.scale(-1); // If the projection is 0, it means that the point is on the top part
+                                        // of the cylinder
+
+        // Otherwise, the point is on the side of the cylinder
+        // NOTE: I use bottomPoint to save the orthogonal point on the ray and not create a new variable in order
+        //       not to harm performance
+        bottomPoint = bottomPoint.add(dir.scale(projection));
+        return point.subtract(bottomPoint).normalize();
     }
 
     @Override

src/geometries/Plane.java

@@ -20,7 +20,7 @@ public class Plane implements Geometry {
      */
     public Plane(Point p1, Point p2, Point p3) {
         this.q0 = p1;
-        this.normal = null; // As for stage 1
+        this.normal = p1.subtract(p2).crossProduct(p1.subtract(p3)).normalize();
     }
 
     /**
@@ -45,7 +45,7 @@ public Vector getNormal() {
 
     @Override
     public Vector getNormal(Point point) {
-        return null;
+        return this.normal;
     }
 
     @Override

src/geometries/Sphere.java

@@ -41,7 +41,7 @@ public double getRadius() {
 
     @Override
     public Vector getNormal(Point point) {
-        return null;
+        return point.subtract(this.center).normalize();
     }
 
     @Override

src/geometries/Tube.java

@@ -2,6 +2,9 @@
 
 import primitives.*;
 
+import static primitives.Util.isZero;
+import static primitives.Util.alignZero;
+
 /**
  * This class is the base for all classes using tubes
  *
@@ -32,7 +35,12 @@ public Ray getAxisRay() {
 
     @Override
     public Vector getNormal(Point point) {
-        return null;
+        Point rayPoint = this.axisRay.getStartPoint();
+        Vector dir = this.axisRay.getDirection();
+        double projection = alignZero(dir.dotProduct(point.subtract(rayPoint)));
+
+        rayPoint = isZero(projection) ? rayPoint : rayPoint.add(dir.scale(projection));
+        return point.subtract(rayPoint).normalize();
     }
 
     @Override

unittests/geometries/PlaneTest.java

@@ -22,14 +22,14 @@ void testConstructor() {
         // TC10: Test when 2 points are the same
         assertThrows(
                 IllegalArgumentException.class,
-                ()->new Plane(p, p, new Point(0, 0, 1)),
+                () -> new Plane(p, p, new Point(0, 0, 1)),
                 "ERROR: ctor() does not throw an exception when 2 points are the same"
         );
 
         // TC11: Test when all 3 points are on the same line
         assertThrows(
                 IllegalArgumentException.class,
-                ()->new Plane(p, new Point(2, 0, 0), new Point(3, 0, 0)),
+                () -> new Plane(p, new Point(2, 0, 0), new Point(3, 0, 0)),
                 "ERROR: ctor() does not throw an exception when all 3 points are on the same line"
         );
     }
@@ -51,8 +51,8 @@ void testGetNormal() {
 
         assertEquals(1, normal.length(), "ERROR: getNormal() vector is not the unit vector");
         assertTrue(
-                normal.equals(new Vector(1, 1, 1)) ||
-                normal.equals(new Vector(-1, -1, -1)),
+                normal.equals(new Vector(1, 1, 1).normalize()) ||
+                normal.equals(new Vector(-1, -1, -1).normalize()),
                 "ERROR: getNormal() wrong value");
     }
 }

unittests/geometries/TriangleTest.java

@@ -28,8 +28,8 @@ void testGetNormal() {
 
         assertEquals(1, normal.length(), "ERROR: getNormal() vector is not the unit vector");
         assertTrue(
-                normal.equals(new Vector(1, 1, 1)) ||
-                        normal.equals(new Vector(-1, -1, -1)),
+                normal.equals(new Vector(1, 1, 1).normalize()) ||
+                        normal.equals(new Vector(-1, -1, -1).normalize()),
                 "ERROR: getNormal() wrong value");
     }
 }