Difference between revisions of "Concise Cg built-in function table"
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SteveBaker (Talk | contribs) (New page: The Cg function table: == Functions == {| border="1" cellspacing="0" cellpadding="5" align="center" ! Function !! Description |- | abs( x ) || Absolute value of x . |- | acos( x ) || ...) |
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Latest revision as of 04:44, 24 December 2009
The Cg function table:
Functions
| Function | Description |
|---|---|
| abs( x ) | Absolute value of x . |
| acos( x ) | Arccos of x in range [0, pi], x in [-1, 1]. |
| all( x ) | true if all components of x != 0 - false otherwise. |
| any( x ) | true if any component of x != 0 - false otherwise. |
| asin( x ) | Arcsin of x in range [-pi/2,pi/2]; x in [-1, 1]. |
| atan( x ) | Arctan of x in range [-pi/2, pi/2]. |
| atan2( y , x ) | Arctan y/x in range [-pi,pi]. |
| ceil( x ) | Smallest integer not less than x . |
| clamp( x , a , b ) | x clamped to the range [a,b]: a if x<a, b if x>b else returns x. |
| cos( x ) | Cos of x. |
| cosh( x ) | Hyperbolic cos of x . |
| cross( A , B ) | Cross product of vectors A and B (A and B must be three-component). |
| ddx( a ) | Partial derivative of a with respect to screen-space x coordinate |
| ddy( a ) | Partial derivative of a with respect to screen-space y coordinate |
| debug(float4 x) | If compiler DEBUG option is enabled, causes shader to halt with x copied to the COLOR output - otherwise it does nothing. |
| degrees( x ) | convert radians to degrees. |
| determinant( x ) | Determinant of matrix x. |
| distance( p1 , p2 ) | Pythagorean distance between p1 and p2. |
| dot( A, B ) | Dot product of A and B. |
| exp( x ) | Exponential func: ex. |
| exp2( x ) | Exponential function 2x. |
| faceforward( N, I, Ng ) | N if dot( Ng , I ) < 0 otherwise (-N). |
| floor( x ) | Largest integer not greater than x. |
| fmod( x , y ) | Remainder of x/y (with the same sign as x). If y==0, result is undefined. |
| frac( x ) | Fractional part of x. |
| frexp( x , out exp ) | Splits x into normalized fraction in the interval [, 1), which is returned, and a power of 2, which is stored in exp . If x==0, both parts of the result are 0. |
| isfinite( x ) | Returns true if x is finite. |
| isinf( x ) | Returns true if x is infinite. |
| isnan( x ) | Returns true if x is NaN. |
| ldexp( x , n ) | x * 2n. |
| length( v ) | Pythagorean length of vector. |
| lerp( a , b , f ) | Linear interpolation: (1 - f)* a + b * f. f can be a vector of same length as a & b. |
| lit( NdotL , NdotH , m ) | Computes lighting coefficients (m is the shininess). Returns: float4: .x=ambient (always 1), .y=diffuse (0 if N.L < 0), .z=specular (0 if N.L<0 or N.H<0); .w==1.0. |
| log( x ) | Natural logarithm (x>0). |
| log2( x ) | Log Base 2 (x>0). |
| log10( x ) | Log Base 10 (x>0). |
| max( a , b ) | Maximum of a and b . |
| min( a , b ) | Minimum of a and b . |
| modf( x , out ip ) | Splits x into int and frac parts (each with the same sign as x). Stores the int part in ip and returns the fractional part. |
| mul( M , N ) | Matrix product of matrix M and matrix N: If M has size AxB, and N has size BxC, returns an AxC. |
| mul( M , v ) | Product of matrix M and column vector v: If M has size AxB, and v is Bx1, returns an Ax1. |
| mul( v , M ) | Product of row vector v and matrix M: If v is a 1xA and M is AxB, returns a 1xB. |
| noise( x ) | Noise function. The returned value is between 0 and 1, and is always the same for a given input value. |
| normalize( v ) | Normalize v. |
| pow( x , y ) | xy |
| radians( x ) | Converts degrees to radians. |
| reflect( I , N ) | Computes reflection of I in a plane with surface normal N. (three-component vectors only). |
| refract( I , N , eta ) | Computes refraction of I in a plane with surface normal N and refractive index eta. Returns (0,0,0) for total internal reflection. (three-component vectors only). |
| round( x ) | Closest integer to x. |
| rsqrt( x ) | Reciprocal square root of x (x>0). |
| saturate( x ) | Clamps x to [0, 1]. |
| sign( x ) | Sign of x (returns -1, 0 or +1) |
| sin( x ) | Sin of x. |
| sincos(float x , out s , out c ) | s is set to sin(x), and c to cos(x). |
| sinh( x ) | Hyperbolic sine of x. |
| smoothstep( min , max , x ) | For values of x between min and max , returns a smoothly varying value that ranges from 0 at x==min to 1 at x==max. x is clamped to the range [min,max] and then returns 2*((x-min)/(max-min))3+3*((x-min)/(max-min))2 |
| step( a , x ) | 0 if x<a, 1 if x>=a |
| sqrt( x ) | Square root of x (x>0) |
| tan( x ) | Tan of x. |
| tanh( x ) | Hyperbolic tan of x. |
| tex1D(sampler1D tex , float s ) | 1D nonprojective texture lookup |
| tex1D(sampler1D tex , float s , float dsdx , float dsdy ) | 1D nonprojective texture lookup with derivatives |
| tex1D(sampler1D tex , float2 sz ) | 1D nonprojective depth compare texture lookup |
| tex1D(sampler1D tex , float2 sz , float dsdx , float dsdy ) | 1D nonprojective depth compare texture lookup with derivatives |
| tex1Dproj(sampler1D tex , float2 sq ) | 1D projective texture lookup |
| tex1Dproj(sampler1D tex , float3 szq ) | 1D projective depth compare texture lookup |
| tex2D(sampler2D tex , float2 s ) | 2D nonprojective texture lookup |
| tex2D(sampler2D tex , float2 s , float2 dsdx , float2 dsdy ) | 2D nonprojective texture lookup with derivatives |
| tex2D(sampler2D tex , float3 sz ) | 2D nonprojective depth compare texture lookup |
| tex2D(sampler2D tex , float3 sz , float2 dsdx , float2 dsdy ) | 2D nonprojective depth compare texture lookup with derivatives |
| tex2Dproj(sampler2D tex , float3 sq ) | 2D projective texture lookup |
| tex2Dproj(sampler2D tex , float4 szq ) | 2D projective depth compare texture lookup |
| texRECT(samplerRECT tex , float2 s ) | 2D nonprojective texture rectangle texture lookup (OpenGL) |
| texRECT(samplerRECT tex , float2 s , float2 dsdx , float2 dsdy ) | 2D nonprojective texture rectangle texture lookup with derivatives (OpenGL) |
| texRECT(samplerRECT tex , float3 sz ) | 2D nonprojective texture rectangle depth compare texture lookup (OpenGL) |
| texRECT(samplerRECT tex , float3 sz , float2 dsdx , float2 dsdy ) | 2D nonprojective depth compare texture lookup with derivatives (OpenGL) |
| texRECTproj(samplerRECT tex , float3 sq ) | 2D texture rectangle projective texture lookup (OpenGL) |
| texRECTproj(samplerRECT tex , float3 szq ) | 2D texture rectangle projective depth compare texture lookup (OpenGL) |
| tex3D(sampler3D tex , float3 s ) | 3D nonprojective texture lookup |
| tex3D(sampler3D tex , float3 s , float3 dsdx , float3 dsdy ) | 3D nonprojective texture lookup with derivatives |
| tex3Dproj(sampler3D tex , float4 sq ) | 3D projective texture lookup |
| texCUBE(samplerCUBE tex , float3 s ) | Cubemap nonprojective texture lookup |
| texCUBE(samplerCUBE tex , float3 s , float3 dsdx , float3 dsdy ) | Cubemap nonprojective texture lookup with derivatives |
| texCUBEproj(samplerCUBE tex , float4 sq ) | Cube map projective texture lookup (ignores q) |
| transpose( M ) | transpose of matrix M |
NOTES:
- s indicates a one-, two-, or three-component texture coordinate.
- z indicates a depth comparison value for shadow map lookups.
- q indicates a perspective value, and is used to divide the texture coordinate ( s ) before the texture lookup is performed.
When you use the texture functions that allow specifying a depth comparison value, the associated texture unit must be configured for depth-compare texturing. Otherwise, no depth comparison will actually be performed.
