GUI functionality fixes.

[architektonas] / src / vector.cpp

diff --git a/src/vector.cpp b/src/vector.cpp
index a60c1334fd4469897510a350d86c6ccf3d8d37d8..57f49fbb8b1d4bc7ae1566c91cdb58586691895f 100644 (file)
--- a/src/vector.cpp
+++ b/src/vector.cpp
@@ -194,7 +194,8 @@ Vector Vector::Unit(void)
 {
        double mag = Magnitude();
 
-       // If the magnitude of the vector is zero, then the Unit vector is undefined...
+       // If the magnitude of the vector is zero, then the Unit vector is
+       // undefined...
        if (mag == 0)
                return Vector(0, 0, 0);
 
@@ -204,17 +205,17 @@ Vector Vector::Unit(void)
 
 double Vector::Magnitude(void)
 {
-       return sqrt(x * x + y * y + z * z);
+       return sqrt((x * x) + (y * y) + (z * z));
 }
 
 
 double Vector::Angle(void)
 {
-       // acos returns a value between zero and PI, which means we don't know which
-       // quadrant the angle is in... Though, if the y-coordinate of the vector is
-       // negative, that means that the angle is in quadrants III - IV.
+       // acos returns a value between zero and TAU/2, which means we don't know
+       // which quadrant the angle is in... However, if the y-coordinate of the
+       // vector is negative, that means that the angle is in quadrants III - IV.
        double rawAngle = acos(Unit().x);
-       double correctedAngle = (y < 0 ? (2.0 * PI) - rawAngle : rawAngle);
+       double correctedAngle = (y < 0 ? TAU - rawAngle : rawAngle);
 
        return correctedAngle;
 }
@@ -243,6 +244,15 @@ bool Vector::isZero(double epsilon/*= 1e-6*/)
 }
 
 
+//
+// Convenience function
+//
+/*static*/ double Vector::Angle(Point p1, Point p2)
+{
+       return Vector(p1, p2).Angle();
+}
+
+
 // Returns the parameter of a point in space to this vector. If the parameter
 // is between 0 and 1, the normal of the vector to the point is on the vector.
 // Note: v1 is the tail, v2 is the head of the line (vector).
@@ -276,10 +286,10 @@ bool Vector::isZero(double epsilon/*= 1e-6*/)
        // This is done using the following formula:
        // (a . b) = ||a|| ||b|| cos(theta)
        // However, have to check for two degenerate cases, where a = cb:
-       // 1, if c > 0, theta = 0; 2, if c < 0, theta = 180°.
+       // 1) if c > 0, theta = 0; 2) if c < 0, theta = 180°.
        // Also, the vectors a & b have to be non-zero.
        // Also, have to check using an epsilon because acos will not return an
-       // exact value if the vectors are orthogonal
+       // exact value if the vectors are orthogonal.
        if (a.isZero() || b.isZero())
                return 0;