目录
Chaptor 1
1.1~1.5 都是基础 1.6对针对Dx介绍一些语法细节
1.6.1 Vector Types
In XNA Math, the core vector type is XMVECTOR, which maps to SIMD hardware registers. This is a 128-bit type that can process four 32-bit floats with a single SIMD instruction. When SSE2 is available, it is defined like so: typedef __m128 XMVECTOR;
注意选择使用XMVECTOR 还是 XMVECTOR* ,既要利用SIMD的计算优势,又要利用 XMVECTOR* 的少占用内存和内存对齐的优势,因此计算用 XMVECTOR ,存储用XMVECTOR* ,中间用math库的函数转化