轉載自http://www.cppblog.com/lai3d/archive/2008/10/23/64889.html

Intrinsic Functions (DirectX HLSL)

The following table lists the intrinsic functions available in HLSL. Each function has a brief description, and a link to a reference page that has more detail about the input argument and return type.

NameSyntaxDescription

abs	abs(x)	Absolute value (per component).
acos	acos(x)	Returns the arccosine of each component of x.
all	all(x)	Test if all components of x are nonzero.
any	any(x)	Test if any component of x is nonzero.
asfloat	asfloat(x)	Convert the input type to a float.
asin	asin(x)	Returns the arcsine of each component of x.
asint	asint(x)	Convert the input type to an integer.
asuint	asuint(x)	Convert the input type to an unsigned integer.
atan	atan(x)	Returns the arctangent of x.
atan2	atan2(y, x)	Returns the arctangent of of two values (x,y).
ceil	ceil(x)	Returns the smallest integer which is greater than or equal to x.
clamp	clamp(x, min, max)	Clamps x to the range [min, max].
clip	clip(x)	Discards the current pixel, if any component of x is less than zero.
cos	cos(x)	Returns the cosine of x.
cosh	cosh(x)	Returns the hyperbolic cosine of x.
cross	cross(x, y)	Returns the cross product of two 3D vectors.
D3DCOLORtoUBYTE4	D3DCOLORtoUBYTE4(x)	Swizzles and scales components of the 4D vector x to compensate for the lack of UBYTE4 support in some hardware.
ddx	ddx(x)	Returns the partial derivative of x with respect to the screen-space x-coordinate.
ddy	ddy(x)	Returns the partial derivative of x with respect to the screen-space y-coordinate.
degrees	degrees(x)	Converts x from radians to degrees.
determinant	determinant(m)	Returns the determinant of the square matrix m.
distance	distance(x, y)	Returns the distance between two points.
dot	dot(x, y)	Returns the dot product of two vectors.
exp	exp(x)	Returns the base-e exponent.
exp2	exp2(x)	Base 2 exponent (per component).
faceforward	faceforward(n, i, ng)	Returns -n * sign(?(i, ng)).
floor	floor(x)	Returns the greatest integer which is less than or equal to x.
fmod	fmod(x, y)	Returns the floating point remainder of x/y.
frac	frac(x)	Returns the fractional part of x.
frexp	frexp(x, exp)	Returns the mantissa and exponent of x.
fwidth	fwidth(x)	Returns abs(ddx(x)) + abs(ddy(x))
GetRenderTargetSampleCount	GetRenderTargetSampleCount()	Returns the number of render-target samples.
GetRenderTargetSamplePosition	GetRenderTargetSamplePosition(x)	Returns a sample position (x,y) for a given sample index.
isfinite	isfinite(x)	Returns true if x is finite, false otherwise.
isinf	isinf(x)	Returns true if x is +INF or -INF, false otherwise.
isnan	isnan(x)	Returns true if x is NAN or QNAN, false otherwise.
ldexp	ldexp(x, exp)	Returns x * 2exp
length	length(v)	Returns the length of the vector v.
lerp	lerp(x, y, s)	Returns x + s(y - x).
lit	lit(n ? l, n ? h, m)	Returns a lighting vector (ambient, diffuse, specular, 1)
log	log(x)	Returns the base-e logarithm of x.
log10	log10(x)	Returns the base-10 logarithm of x.
log2	log2(x)	Returns the base-2 logarithm of x.
max	max(x, y)	Selects the greater of x and y.
min	min(x, y)	Selects the lesser of x and y.
modf	modf(x, out ip)	Splits the value x into fractional and integer parts.
mul	mul(x, y)	Performs matrix multiplication using x and y.
noise	noise(x)	Generates a random value using the Perlin-noise algorithm.
normalize	normalize(x)	Returns a normalized vector.
pow	pow(x, y)	Returns xy.
radians	radians(x)	Converts x from degrees to radians.
reflect	reflect(i, n)	Returns a reflection vector.
refract	refract(i, n, R)	Returns the refraction vector.
round	round(x)	Rounds x to the nearest integer
rsqrt	rsqrt(x)	Returns 1 / sqrt(x)
saturate	saturate(x)	Clamps x to the range [0, 1]
sign	sign(x)	Computes the sign of x.
sin	sin(x)	Returns the sine of x
sincos	sincos(x, out s, out c)	Returns the sine and cosine of x.
sinh	sinh(x)	Returns the hyperbolic sine of x
smoothstep	smoothstep(min, max, x)	Returns a smooth Hermite interpolation between 0 and 1.
sqrt	sqrt(x)	Square root (per component)
step	step(a, x)	Returns (x >= a) ? 1 : 0
tan	tan(x)	Returns the tangent of x
tanh	tanh(x)	Returns the hyperbolic tangent of x
tex1D	tex1D(s, t)	1D texture lookup.
tex1Dbias	tex1Dbias(s, t)	1D texture lookup with bias.
tex1Dgrad	tex1Dgrad(s, t, ddx, ddy)	1D texture lookup with a gradient.
tex1Dlod	tex1Dlod(s, t)	1D texture lookup with LOD.
tex1Dproj	tex1Dproj(s, t)	1D texture lookup with projective divide.
tex2D	tex2D(s, t)	2D texture lookup.
tex2Dbias	tex2Dbias(s, t)	2D texture lookup with bias.
tex2Dgrad	tex2Dgrad(s, t, ddx, ddy)	2D texture lookup with a gradient.
tex2Dlod	tex2Dlod(s, t)	2D texture lookup with LOD.
tex2Dproj	tex2Dproj(s, t)	2D texture lookup with projective divide.
tex3D	tex3D(s, t)	3D texture lookup.
tex3Dbias	tex3Dbias(s, t)	3D texture lookup with bias.
tex3Dgrad	tex3Dgrad(s, t, ddx, ddy)	3D texture lookup with a gradient.
tex3Dlod	tex3Dlod(s, t)	3D texture lookup with LOD.
tex3Dproj	tex3Dproj(s, t)	3D texture lookup with projective divide.
texCUBE	texCUBE(s, t)	Cube texture lookup.
texCUBEbias	texCUBEbias(s, t)	Cube texture lookup with bias.
texCUBEgrad	texCUBEgrad(s, t, ddx, ddy)	Cube texture lookup with a gradient.
texCUBElod	tex3Dlod(s, t)	Cube texture lookup with LOD.
texCUBEproj	texCUBEproj(s, t)	Cube texture lookup with projective divide.
transpose	transpose(m)	Returns the transpose of the matrix m.
trunc	trunc(x)	Truncates floating-point value(s) to integer value(s)

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表 3-1 HLSL內置函數

函數名?????????? ?用法

abs???????????????????????? 計算輸入值的絕對值。

acos??????????????????????? 返回輸入值反余弦值。

all?????????????????????????? 測試非0值。

any???????????????????????? 測試輸入值中的任何非零值。

asin???????????????????????? 返回輸入值的反正弦值。

atan??????????????????????? 返回輸入值的反正切值。

atan2?????????????????????? 返回y/x的反正切值。

ceil???????????????????????? 返回大于或等于輸入值的最小整數。

clamp????????????????????? 把輸入值限制在[min, max]范圍內。

clip???????????????????????? 如果輸入向量中的任何元素小于0，則丟棄當前像素。

cos???????????????????????? 返回輸入值的余弦。

cosh?????????????????????? 返回輸入值的雙曲余弦。

cross????????????????????? 返回兩個3D向量的叉積。

ddx???????????????????????? 返回關于屏幕坐標x軸的偏導數。

ddy???????????????????????? 返回關于屏幕坐標y軸的偏導數。

degrees?????????????????? 弧度到角度的轉換

determinant????????????? 返回輸入矩陣的值。

distance?????????????????? 返回兩個輸入點間的距離。

dot????????????????????????? 返回兩個向量的點積。

exp???????????????????????? 返回以e為底數，輸入值為指數的指數函數值。

exp2?????????????????????? 返回以2為底數，輸入值為指數的指數函數值。

faceforward???????????? 檢測多邊形是否位于正面。

floor?????????????????????? 返回小于等于x的最大整數。

fmod?????????????????????? 返回a / b的浮點余數。

frac??????????????????????? 返回輸入值的小數部分。

frexp?????????????????????? 返回輸入值的尾數和指數

fwidth???????????????????? 返回 abs ( ddx (x) + abs ( ddy(x))。

isfinite???????????????????? 如果輸入值為有限值則返回true，否則返回false。

isinf??????????????????????? 如何輸入值為無限的則返回true。

isnan?????????????????????? 如果輸入值為NAN或QNAN則返回true。

ldexp?????????????????????? frexp的逆運算，返回 x * 2 ^ exp。

len / lenth??????????????? 返回輸入向量的長度。

lerp???????????????????????? 對輸入值進行插值計算。

lit??????????????????????????? 返回光照向量（環境光，漫反射光，鏡面高光，1）。

log????????????????????????? 返回以e為底的對數。

log10????????????????????? 返回以10為底的對數。

log2??????????????????????? 返回以2為底的對數。

max??????????????????????? 返回兩個輸入值中較大的一個。

min???????????????????????? 返回兩個輸入值中較小的一個。

modf?????????????????????? 把輸入值分解為整數和小數部分。

mul???????????????????????? 返回輸入矩陣相乘的積。

normalize???????????????? 返回規范化的向量，定義為 x / length(x)。

pow??????????????????????? 返回輸入值的指定次冪。

radians??????????????????? 角度到弧度的轉換。

reflect???????????????????? 返回入射光線i對表面法線n的反射光線。

refract???????????????????? 返回在入射光線i，表面法線n，折射率為eta下的折射光線v。

round????????????????????? 返回最接近于輸入值的整數。

rsqrt?????????????????????? 返回輸入值平方根的倒數。

saturate?????????????????? 把輸入值限制到[0, 1]之間。

sign??????????????????????? 計算輸入值的符號。

sin????????????????????????? 計算輸入值的正弦值。

sincos???????????????????? 返回輸入值的正弦和余弦值。

sinh??????????????????????? 返回x的雙曲正弦。

smoothstep????????????? 返回一個在輸入值之間平穩變化的插值。

sqrt???????????????????????? 返回輸入值的平方根。

step??????????????????????? 返回（x >= a）? 1 : 0。

tan????????????????????????? 返回輸入值的正切值。

fanh??????????????????????? 返回輸入值的雙曲線切線。

transpose???????????????? 返回輸入矩陣的轉置。

tex1D*??????????????????? 1D紋理查詢。

tex2D*??????????????????? 2D紋理查詢。

tex3D*??????????????????? 3D紋理查詢。

texCUBE*??????????????? 立方紋理查詢。

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