[bb] Vector Math library by Beeps [ 1+ years ago ]

BlitzBot · June 29, 2017, 00:28:42

Title : Vector Math library
Author : Beeps
Posted : 1+ years ago

Description : A simple blitz include that gives you most of the vector maths functions. (Not fully tested)

Code :

Code (blitzbasic) Select

;vector maths lib by Beeps

;used to normalize vector
Const vector_tol#=0.0001

Type vector
	Field x#
	Field y#
	Field z#
	Field magnitude#
End Type

Function vector_createVector.vector(vx#,vy#,vz#)
	;create a populated vector and return
	vec.vector=New vector
	vecx=vx
	vecy=vy
	vecz=vz
	Return vec
End Function

Function vector_calcMagnitude(vec.vector)
	;calc the magnitude of a vector and stor in vector
	vecmagnitude=Sqr(vecx*vecx + vecy*vecy + vecz*vecz) 
End Function

Function vector_normalize(vec.vector)
	;normalize a vector so it's length = 1 and apply tolerance based on our constant tolerance value
	m#=Sqr(Sqr(vecx*vecx + vecy*vecy + vecz*vecz) )
	If m<= vector_tol Then m=1
	vecx=vecx/m
	vecy=vecy/m
	vecz=vecz/m
	If Abs(vecx)<vector_tol Then vecx=0
	If Abs(vecy)<vector_tol Then vecy=0
	If Abs(vecz)<vector_tol Then vecz=0
End Function	

Function vector_reverse(vec.vector)
	;reverse a vector
	vecx=-vecx
	vecy=-vecy
	vecz=-vecz
End Function

Function vector_add.vector(vec1.vector,vec2.vector)
	;add two vectors together and return the resulting vector
	result.vector=New vector
	
	resultx=vec1x+vec2x
	resulty=vec1y+vec2y
	resultz=vec1z+vec2z
	
	Return result
End Function

Function vector_subtract.vector(vec1.vector,vec2.vector)
	;subtract vec1 from vec2 and return the resulting vector
	result.vector=New vector
	
	resultx=vec1x-vec2x
	resulty=vec1y-vec2y
	resultz=vec1z-vec2z
	
	Return result
End Function

Function vector_scalarMultiply.vector(vec1.vector,scale#)
	;scalar multiplication of a vector with result returned as new vector
	;used to scale a vector by 'scale'
	result.vector=New vector
	resultx=vec1x*scale
	resulty=vec1y*scale
	resultz=vec1z*scale
	Return result
End Function

Function vector_scalarDivision.vector(vec1.vector,scale#)
	;scalar division of a vector with result returned as new vector
	;used to scale a vector
	result.vector=New vector
	resultx=vec1x/scale
	resulty=vec1y/scale
	resultz=vec1z/scale
	Return result
End Function

Function vector_conjugate.vector(vec1.vector)
	;conjugate operator takes the negative of each vector component
	;can be used when subtracting one vector from another or for
	;reversing the direction of a vector.
	;applying conjugate is the same as reversing a vector
	;returns a new vector
	result.vector = New vector
	resultx=-vec1x
	resulty=-vec1y
	resultz=-vec1z
	Return result
End Function

Function vector_crossProduct.vector(vec1.vector,vec2.vector)
	;takes vec1 and vec2 and returns the cross product vec1 X vec2
	;the cross product is a vector perpendicular to both vec1 and vec2
	;this is the normal of 2 vectors
	result.vector=New vector
	
	resultx=(vec1y*vec2z) - (vec1z*vec2y)
	resulty=(vec1z*vec2x) - (vec1x*vec2z) 
	resultz=(vec1x*vec2y) - (vec1y*vec2x)

	Return result
End Function

Function vector_dotProduct#(vec1.vector,vec2.vector)
	;calculate and return the dot product of 2 vectors (distance)
	result#=(vec1x*vec2x)+(vec1y*vec2y)+(vec1z*vec2z)
	Return result
End Function

Function vector_tripleScalarProduct#(vec1.vector,vec2.vector,vec3.vector)
	;calculate the triple scalar function and return it
	result#=          vec1x * ( (vec2y*vec3z ) - (vec2z * vec3y) ) 
	result=result + ( vec1y * ( (-vec2x*vec3z) + (vec2z * vec3x) ) ) 
	result=result + ( vec1z * ( ( vec2x*vec3y) + (vec2y * vec3x) ) )
	Return result
End Function

Comments :

Dreamora(Posted 1+ years ago)

The crossproduct is wrongresulty = (vec1z*vec2x) - (vec1x*vec2z)

Beaker(Posted 1+ years ago)

Replace..Sqr(vecx^2 + vecy^2 + vecz^2)..with..Sqr(vecx*vecx + vecy*vecy + vecz*vecz)..for speed.What I do is keep a global called result.vector or vec_result.vector to store the result in. Speeds things up and reduces risk of memory leaks. You can even return it as well if you want to store it elsewhere.

Beeps(Posted 1+ years ago)

Done. Thanks guys!

Chroma(Posted 1+ years ago)

<div class="quote"> What I do is keep a global called result.vector or vec_result.vector to store the result in. Speeds things up and reduces risk of memory leaks. </div>Ah ha! Pure genious Beaker. I shall implement this into my Vector Lib this very instant!

_Skully(Posted 1+ years ago)

So with this are the x,y,z values normals and the magnitude a multiplier?

SyntaxBomb - Indie Coders

[bb] Vector Math library by Beeps [ 1+ years ago ]

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