HLSL有一个丰富的内建函数的集合，它们对3D图形来说非常有用。下表是一个删减了的列表，注意：要得到更多的参考，可以参看DirectX文档中内建HLSL函数的完整列表。
以下表格中，//<variable>//表示变量variable的模（例如向量的绝对值）。
|
函数
|
描述
|
|
abs(x)
|
返回
|x|
|
|
ceil(x)
|
返回
≥ x
的最小整数
|
|
clamp(x, a, b)
|
Clamps x to the range [a, b] and returns the result.
|
|
cross(u, v)
|
返回
u × v（叉积）
|
|
degrees(x)
|
转换
x 从弧度到角度
|
|
determinant(M)
|
返回矩阵M的行列式det(M)
|
|
distance(u, v)
|
返回u点和v点之间的距离||v
- u||
|
|
dot(u, v)
|
返回
u · v（点积）
|
|
floor(x)
|
返回
≤ x
的最大整数
|
|
length(v)
|
返回
||v||
|
|
lerp(u, v, t)
|
在u和v之间线性插值，参数
t
在[0,
1 ]之间变化。
|
|
log(x)
|
返回
ln(x)
|
|
log10(x)
|
返回
log10(x)
|
|
log2(x)
|
返回
log2(x)
|
|
max(x, y)
|
如果x ≥ y，则返回
x；否则返回
y
|
|
min(x, y)
|
如果
x ≤ y，返回x；否则返回
y
|
|
mul(M, N)
|
返回矩阵乘积
MN. 注意：矩阵乘积必须是已定义的.
如果M是一个向量，它被作为一个行向量，则向量－矩阵（vector-matrix）乘法是已定义的。类似的,如果N 是一个向量，他被作为一个列向量，则矩阵－向量（matrix-vector）乘法是已定义的。
|
|
normalize(v)
|
返回
v/∥v∥
|
|
pow(b, n)
|
返回
bn
|
|
radians(x)
|
转换
x 从
角度
到
弧度
|
|
reflect(v, n)
|
给定向量v和表面法线n，计算其反射向量
|
|
refract(v,n, eta)
|
给定向量v、表面法线n和两种材质的两个索引的比率eta，计算其折射向量.
翻看一下物理书中Snell的规则或者在互联网上搜索一下关于refraction（反射）的信息
|
|
rsqrt(x)
|
返回x的平方根的倒数
|
|
saturate(x)
|
返回clamp(x,
0.0, 1.0)
|
|
sin(x)
|
返回x的正弦,其中x单位为弧度
|
|
sincos(in x, out s, out c)
|
返回x的正弦和余弦，其中x单位为弧度
|
|
sqrt(x)
|
返回x的平方根
|
|
tan(x)
|
返回x的正切,其中
x 单位为弧度
|
|
transpose(M)
|
返回M的转置
|
abs (Direct3D 9 HLSL)
Computes the absolute value of each component.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float, int |
any |
| ret |
out |
same as input x |
same as input x |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_1_4 |
ceil (Direct3D 9 HLSL)
Returns the smallest integer which is greater than or
equal to x.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float |
any |
| ret |
out |
same as input x |
float |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_2_0 |
clamp (Direct3D 9 HLSL)
Clamps x to the range [min, max].
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float, int |
any |
| min |
in |
same as input x |
float, int |
same dimension(s) as input x |
| max |
in |
same as input x |
float, int |
same dimension(s) as input x |
| ret |
out |
same as input x |
float, int |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_1_4 |
cross (Direct3D 9 HLSL)
Returns the cross product of two 3D vectors.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
vector |
float |
3 |
| y |
in |
vector |
float |
3 |
| ret |
out |
vector |
float |
3 |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_1_4 |
degrees (Direct3D 9 HLSL)
Converts x from radians to degrees.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float |
any |
| ret |
out |
same as input x |
float |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_2_0 |
determinant (Direct3D 9 HLSL)
Returns the determinant of the square matrix m.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| m |
in |
matrix |
float |
any (number of rows = number of columns) |
| ret |
out |
scalar |
float |
1 |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_1_4 |
distance (Direct3D 9 HLSL)
Returns the distance between two points x and y.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
vector |
float |
any |
| y |
in |
vector |
float |
same dimension(s) as input x |
| ret |
out |
scalar |
float |
1 |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_2_0 |
dot (Direct3D 9 HLSL)
Returns the • product of two vectors, x and y.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
vector |
float, int |
any |
| y |
in |
vector |
float, int |
same dimensions(s) as input x |
| ret |
out |
scalar |
float, int |
1 |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_1_1 |
floor (Direct3D 9 HLSL)
Returns the greatest integer which is less than or
equal to x.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float |
any |
| ret |
out |
same as input x |
float |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_2_0 |
length (Direct3D 9 HLSL)
Returns the length of the vector x.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
vector |
float |
any |
| ret |
out |
scalar |
float |
1 |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_2_0 |
lerp (Direct3D 9 HLSL)
Returns x + s(y - x). This linearly interpolates
between x and y, such that the return value is x when s is 0, and y when s is 1.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float |
any |
| y |
in |
same as input x |
float |
same dimension(s) as input x |
| s |
in |
same as input x |
float |
same dimension(s) as input x |
| ret |
out |
same as input x |
float |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_1_4 |
log (Direct3D 9 HLSL)
Returns the base-e logarithm of x. If x is negative,
the function returns indefinite. If x is 0, the function returns +INF.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float |
any |
| ret |
out |
same as input x |
float |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_2_0 |
log10 (Direct3D 9 HLSL)
Returns the base-10 logarithm of x. If x is negative,
the function returns indefinite. If x is 0, the function returns +INF.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float |
any |
| ret |
out |
same as input x |
float |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_2_0 |
log2 (Direct3D 9 HLSL)
Returns the base-2 logarithm of x. If x is negative,
the function returns indefinite. If x is 0, the function returns +INF.
Syntax
Where:
| Name |
In/Out |
Template Type |
Component Type |
Size |
| x |
in |
scalar, vector, or matrix |
float |
any |
| ret |
out |
same as input x |
float |
same dimension(s) as input x |
Minimum Shader Version
This intrinsic function is supported in the following
(or above) shader versions:
| Vertex Shader |
Pixel Shader |
| vs_1_1 |
ps_2_0 |