Vector cal library

[Tsunghao-C]

1. Created a vector module that includes 10 basic vector operations

• the struct of vector is defined in vector.h, which consists two double number x and y.
• vec_init(): initialize a vector object with x and y in the argument
• vec_add(), vec_sub(), vec_muls(): the first vector argument value will change after operation, while the 2nd argument will not be changed
• vec_mirror(), vec_transpose(): change the vector argument by mirroring or trasponsing
• vec_rotate(): rotate the vector argument COUNTERCLOCKWISE by angle (in double).
• vec_dot(), vec_absv(), vec_dist(): returns a double value of inner dot multiplication, absolute value of a vector, or the distance between two vectors.

2. Added three vector data (p_dir, p_pos, p_cam) in the main data structure

3. Initialized player position and direction vectors as well when parsing the map.

4. The positive X direction is defined to be SOUTH and the positive Y direction is define to be EAST

     y y
     | |
     0 1 2 3 4 5 6 7   -> EAST
   

x = 0 1 1 1 1 1 1 1 1
x = 1 1 0 0 0 0 0 0 1
x = 2 1 0 0 0 0 0 1 1
|
SOUTH

[Haliris]

LGTM! 👍