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Index › Programming Questions & Help › Syntax Questions › About the composition of rotation
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About the composition of rotation (Read 373 times)
yiyangchen2009
About the composition of rotation
Mar 15th, 2009, 10:03am  
Hello everyone.
In left hand coordinate system,
rotateX(a) corresponds to the matrix
M(a)=  {1,0,0;0,cos(a),-sin(a);0,sin(a),cos(a)}
       
rotateY(b) corresponds to the matrix
M(b)=  {cos(b),0,sin(b);0,1,0;-sin(b),0,cos(b)}

Right?

So their composition in order,i.e,rotateX(a) followed by
rotateY(b) corresponds to the matrix
M(a,b)=M(a)*M(b)
Is that right?I made a test where the matrix printed by the function showMatrix() seems the same as computed in mathCAD.
Any advise is appreciated...Thanks.
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liudr
Re: About the composition of rotation
Reply #1 - Mar 28th, 2009, 12:13pm  
I share your curiosity. My part of the question: How come the coordinates are left-handed? Are all computer graphics coordinates left-handed? Thanks.
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