max (Direct3D 9 HLSL)
Selects the greater of x and y.
Syntax
ret max(x, y)
Where:
Name In/Out Template Type Component Type Size
x in scalar, vector, or matrix float, int any
y in same as input x float, int same dimension(s) as input x
ret return type 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
min (Direct3D 9 HLSL)
Selects the lesser of x and y.
Syntax
ret min(x, y)
Where:
Name In/Out Template Type Component Type Size
x in scalar, vector, or matrix float, int any
y in same as input x float, int same dimension(s) as input x
ret return type 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
mul (Direct3D 9 HLSL)
Performs matrix multiplication between x and y. If x is a vector, it treated as a row vector. If y is a vector, it is treated as a column vector. The inner dimension x-columns and y-rows must be equal. The result has the dimension x-rows x y-columns.
Syntax
ret mul(x, y)
There are 9 overloaded versions of this function, to handle the different cases for the types and sizes of the x and y input arguments. The following table lists these versions.
Version Name Purpose Template Type Component Type Size
1
x in scalar float, int 1
y in scalar same as input x 1
ret out scalar same as input x 1
2
x in scalar float, int 1
y in vector float, int any
ret out vector float, int same dimension(s) as input y
3
x in scalar float, int 1
y in matrix float, int any
ret out matrix same as input y same dimension(s) as input y
4
x in vector float, int any
y in scalar float, int 1
ret out vector float, int same dimension(s) as input x
5
x in vector float, int any
y in vector float, int same dimension(s) as input x
ret out scalar float, int 1
6
x in vector float, int any
y in matrix float, int rows = same dimension(s) as input x, columns = any
ret out vector float, int same dimension(s) as input y columns
7
x in matrix float, int any
y in scalar float, int 1
ret out matrix float, int same dimension(s) as input x
8
x in matrix float, int any
y in vector float, int number of columns in input x
ret out vector float, int number of rows in input x
9
x in matrix float, int any
y in matrix float, int rows = number of columns in input x
ret out matrix float, int rows = number of rows in input x, columns = number of columns in input y
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
normalize (Direct3D 9 HLSL)
Returns the normalized vector x / length(x). If the length of x is 0, the result is indefinite.
Syntax
ret normalize(x)
Where:
Name In/Out Template Type Component Type Size
x in vector 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
pow (Direct3D 9 HLSL)
Returns xy.
Syntax
ret pow(x, y)
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
ret out same as input x float same dimension(s) as input x
Remarks
Special cases:
If x = 0, then the result will always be 0. If x < 0, there will be a compile error.
This intrinsic function is supported in the following (or above) shader versions:
Vertex Shader Pixel Shader
vs_1_1 ps_2_0
radians (Direct3D 9 HLSL)
Converts x from degrees to radians.
Syntax
ret radians(x)
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_1_1
reflect (Direct3D 9 HLSL)
Returns the reflection vector v, given the entering ray direction i, and the surface normal n, as in:
v = i - 2 * dot(i, n) * n
Syntax
ret reflect(i, n)
Where:
Name In/Out Template Type Component Type Size
i in vector float any
n in vector float same dimension(s) as input i
ret out vector float same dimension(s) as input i
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
refract (Direct3D 9 HLSL)
Returns the refraction vector given the entering ray direction i, the surface normal n, and the refraction index ri. If the angle between i and n is too great for a given eta, refract returns (0,0,0).
Syntax
ret refract(i, n, ri)
Where:
Name In/Out Template Type Component Type Size
i in vector float any
n in vector float same dimension(s) as input i
ri in scalar float 1
refraction vector out vector float same dimension(s) as input i
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
rsqrt (Direct3D 9 HLSL)
Returns 1 / sqrt(x).
Syntax
ret rsqrt(x)
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
saturate (Direct3D 9 HLSL)
Clamps x to the range [0, 1].
Syntax
ret saturate(x)
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_1_1
sin (Direct3D 9 HLSL)
Returns the sine of x.
Syntax
ret sin(x)
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
sincos (Direct3D 9 HLSL)
Returns the sine and cosine of x. sin(x) is stored in the output parameter s. cos(x) is stored in the output parameter c.
Syntax
sincos(x, out s, out c)
Where:
Name In/Out Template Type Component Type Size
x in scalar, vector, or matrix float any
s out same as input x float same dimension(s) as input x
c 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
sqrt (Direct3D 9 HLSL)
Square root (per component).
Syntax
ret sqrt(x)
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
tan (Direct3D 9 HLSL)
Returns the tangent of x.
Syntax
ret tan(x)
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
transpose (Direct3D 9 HLSL)
Returns the transpose of the input matrix x. If the dimensions of the source matrix is p-rows x q-columns, the resulting matrix is q-columns x p-rows.
Syntax
ret transpose(x)
Where:
Name In/Out Template Type Component Type Size
x in matrix float, int, bool any
ret out matrix float, int, bool rows = same number of columns as input x, columns = same number of rows 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_1
大多数函数已经重载以使其可以对所有内建类型有意义。例如，abs对所有数值类型有意义，所以它为所有这些数值类型进行了重载。又例如，叉积的叉乘仅对3D向量有意义，所以它对所有类型的3D向量（比如：int，float，double的3D向量）进行了重载。另一方面，线性插值——lerp，对于数值、2D、3D和4D向量有意义，因此重载了这些类型。
注意：如果你传递进去一个非数值类型到一个（要求）数值类型的函数，也就是一个仅能对数值类型进行操作的函数（比如：cos(x)），那么这个函数会对传进去的每个分量进行操作。例如，你写：
floats v = float3 (0.0f, 0.0f, 0.0f);
v = cos(v);
那么函数将会对每个分量进行操作：v=(cos(x),cos(y),cos(z))。
下例展示了这些固有的函数可能被调用的方式：
float x = sin(1.0f); // sine of 1.0f radian.
float y = sqrt(4.0f); // square root of 4.
vector u = {1.0f, 2.0f, -3.0f, 0.0f};
vector v = {3.0f, -1.0f, 0.0f, 2.0f};
float s = dot(u, v); // compute dot product of u and v.
float3 i = {1.0f, 0.0f, 0.0f};
float3 j = {0.0f, 1.0f, 0.0f};
float3 k = cross(i, j); // compute cross product of i and j.
matrix<float, 2, 2> M = {1.0f, 2.0f, 3.0f, 4.0f};
matrix<float, 2, 2> T = transpose(M); // compute transpose
