Modern Math Dot

Home › Math Library › Math Library › Dot

Dot

Returns the dot product of two vectors; zero means they are perpendicular.

Syntax

Dot( byref a as Vec3, byref b as Vec3 ) as float32

Notes

• Overloaded for Vec2, Vec3, Vec4 and Quat, in both the single and double families.
• Zero means perpendicular, positive means the vectors point the same way, negative means opposite -- which is why it is the test for which side of a plane a point is on.
• Dot( a, a ) is LengthSquared( a ), and that identity is how the length is computed.

Examples

#import "std/numeric"
using numeric

dim as Vec3 a = type<Vec3>( 1, 2, 3 ), b = type<Vec3>( 4, 5, 6 )

print Dot( a, b )            '' 32

'' Zero means perpendicular
dim as Vec3 x = type<Vec3>( 1, 0, 0 ), y = type<Vec3>( 0, 1, 0 )
print Dot( x, y )            '' 0

'' Dot with itself is the squared length
print Dot( a, a ) = LengthSquared( a )        '' -1 (true)

---

Library: Math Library
Category: Math Library
Documented under: Members