I would need a small inline library for doing basic math
operation (and maybe others usable small inline routines)
i mean like dot cross normalize vector and stuff like that,
(specyficaly i am doing basic raytracing and my naive functions
i think are slower than the things i could find somewhere and use)
smething that is usable efficient and i could just include it
in my code
is there something like that?
You cant be sure that GCC inlines certain functions. (thats a good thing because it also optimizes for instruction cache, etc) and there is not much to speed up on a 2 line function I think. Maybe change divisions to multiplications, eliminate every branch?
Here is my dot, normalize, cross:
static float scalarNumber(const CVector3f *const v1, const CVector3f *const v2) {return (v1->x * v2->x + v1->y * v2->y + v1->z * v2->z);}
//********************************************************************
float CVector3f::normalize(){
float length = sqrt( x*x + y*y + z*z);
if( unlikely( CMathUtilEA::isNearZero( length)))
return 0.0f;
else{
x /= length;
y /= length;
z /= length;
return length;
}
}
//********************************************************************
void CVector3f::crossP(const CVector3f *const A, const CVector3f *const B, const CVector3f *const C){
CVector3f v1( A, B);
CVector3f v2( A, C);
x = v1.y * v2.z - v1.z * v2.y;
y = v1.z * v2.x - v1.x * v2.z;
z = v1.x * v2.y - v1.y * v2.x;
}
You cant be sure that GCC inlines certain functions. (thats a good thing because it also optimizes for instruction cache, etc) and there is not much to speed up on a 2 line function I think. Maybe change divisions to multiplications, eliminate every branch?
Here is my dot, normalize, cross:
static float scalarNumber(const CVector3f *const v1, const CVector3f *const v2) {return (v1->x * v2->x + v1->y * v2->y + v1->z * v2->z);} //******************************************************************** float CVector3f::normalize(){ float length = sqrt( x*x + y*y + z*z); if( unlikely( CMathUtilEA::isNearZero( length))) return 0.0f; else{ x /= length; y /= length; z /= length; return length; } } //******************************************************************** void CVector3f::crossP(const CVector3f *const A, const CVector3f *const B, const CVector3f *const C){ CVector3f v1( A, B); CVector3f v2( A, C); x = v1.y * v2.z - v1.z * v2.y; y = v1.z * v2.x - v1.x * v2.z; z = v1.x * v2.y - v1.y * v2.x; }
this is bad for sure you should count the inversion and does 3 multiplies in normalize - and better is to get some better code
at all (using sse intrinsics of something)
and better is to get some better code at all
Like unreadable, non-portable, bugprone hand-optimized code? inline assembly?
If you code in a way that helps the compiler it will usually output pretty neat assembly.
(But anyway you asked for a proper library and not for coding advice so sorry, disregard me.)
and better is to get some better code at all
Like unreadable, non-portable, bugprone hand-optimized code? inline assembly?
If you code in a way that helps the compiler it will usually output pretty neat assembly.
(But anyway you asked for a proper library and not for coding advice so sorry, disregard me.)
your code will make three divisions and i think it will be about 2x slower than necessary -i am searching for faster routines not slower
+1 for GLM. Write your own library only if you are completely confident of what you're doing.
this is heavy c++ i need something thus kind but in c and i would preffer smaller thing - may be just one .h file
http://www.cs.kent.edu/~farrell/cg02/reference/natetut/glm.c
http://www.cs.kent.edu/~farrell/cg02/reference/natetut/glm.h
It is definitely not as full-featured as glm proper, and definitely is not heavily optimized.
Other choices (not aimed directly at graphics programming):
http://www.gnu.org/software/gsl/
http://www.netlib.org/clapack/ (LAPACK, Linear Algebra PACKage)
http://math-atlas.sourceforge.net/ (BLAS, Basic Linear Algebra Subprograms)
I honestly haven't liked any of the choices I could find in C as much as I like GLM for C++, and the math library issue is probably the only reason I'm even using C++ for my current project instead of C.
I need much simpler thing preferably just one header file with some optymized basic math inline routines (could be inline assembly)
