Make nan==nan true for GDScript

After discussing this with Reduz this seemed like the best way to
fix #7354. This will make composite values that contain NaN in the same
places as well as the same other values compare as the same.

Additionally non-composite values now also compare equal if they are
both NaN. This breaks IEEE specifications but this is probably what most
users expect. There is a GDScript function check for NaN if the user
needs this information.

This fixes #7354 and probably also fixes #6947

1 files changed, 11 insertions, 0 deletions

diff --git a/core/math/vector3.cpp b/core/math/vector3.cpp
index 2ab5fa0465..7fdb54bb69 100644
--- a/core/math/vector3.cpp
+++ b/core/math/vector3.cpp
@@ -176,6 +176,17 @@ Vector3 Vector3::cubic_interpolate(const Vector3& p_b,const Vector3& p_pre_a, co
 	return out;
 }
 # endif
+bool Vector3::nan_equals(const Vector3& p_v) const {
+	return (x == p_v.x && y == p_v.y && z == p_v.z) ||
+			(x == p_v.x && y == p_v.y && isnan(z) && isnan(p_v.z)) ||
+			(x == p_v.x && isnan(y) && isnan(p_v.y) && z == p_v.z) ||
+			(isnan(x) && isnan(p_v.x) && y == p_v.y && z == p_v.z) ||
+			(x == p_v.x && isnan(y) && isnan(p_v.y) && isnan(z) && isnan(p_v.z)) ||
+			(isnan(x) && isnan(p_v.x) && y == p_v.y && isnan(z) && isnan(p_v.z)) ||
+			(isnan(x) && isnan(p_v.x) && isnan(y) && isnan(p_v.y) && z == p_v.z) ||
+			(isnan(x) && isnan(p_v.x) && isnan(y) && isnan(p_v.y) && isnan(z) && isnan(p_v.z));
+}
+
 Vector3::operator String() const {
 
 	return (rtos(x)+", "+rtos(y)+", "+rtos(z));