graphene:vec4-init-from-vec3 (v src w)

v -- a graphene:vec4-t instance
source -- a graphene:vec4-t instance
w -- a number coerced to a float with the value of the fourth component of v

The initialized graphene:vec4-t instance.

Initializes a graphene:vec4-t instance using another graphene:vec3-t instance and the value of w. This function can be called multiple times.