cg基础

1. row-major or column-major

2.orthogonal matrices

3.why cameras always point along the world coordinate system negative z-axis......still dont know why

4 barycentric coordinates wiki

P = aA + bB + cC [abc正比于PBC,PCA,PAB的面积]

5.三角形面积公式

1)海伦公式。abc为三边长，p=(a+b+c)/2

   S=√[p(p-a)(p-b)(p-c)]

2)ABC为三定点