Ｕnity透過 Camera.projectionMatrix 回算出aspect 與 fov

https://developer.vuforia.com/forum/unity-extension-technical-discussion/vertical-fov-unity

這裡有寫道

Matrix4x4 mat = Camera.main.projectionMatrix;

 

float a = mat[0];

float b = mat[5];

float c = mat[10];

float d = mat[14];

 

float aspect_ratio = b / a;

 

float k = (c - 1.0f) / (c + 1.0f);

float clip_min = (d * (1.0f - k)) / (2.0f * k);

float clip_max = k * clip_min;

 

float RAD2DEG = 180.0f / 3.14159265358979323846f;

float fov = RAD2DEG * (2.0f * (float)Math.Atan(1.0f / b));