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#Actualmast4as

Posted 08 January 2013 - 03:02 PM

Kevin by talking to the guys today I realised I made a mistake in my explanation. I amended the post above. Sorry about that. Please, if you find the time go through it again. You say you use column-major rather than row-major. The explanation I gave works for row-major so technically you will need to transpose the matrix. If other words for column major your matrix should be written with the basis vectors vertically:

   |Rx Ux Fx|
M =|Ry Uy Fy| if you use column-major
   |Rz Uz Fz|

Them matrix mult should be written as

        |Rx Ux Fx|   |Vx|
M * V = |Ry Uy Fy| * |Vy|
        |Rz Uz Fz|   |Vz|

For the right- left-hand naming convention I would also have a look at this page:

http://scratchapixel.com/lessons/3d-basic-lessons/lesson-4-geometry/math-operations-on-points-and-vectors/

Now from my understanding, there's a lot of people out there using different names for the same thing which is very confusing. That's why I like to refer to this page and try to stick to their convention which seems to be following some of the industry standards. Hopefully what's in their website is accurate and reliable ;-)


#3mast4as

Posted 08 January 2013 - 03:00 PM

Kevin by talking to the guys today I realised I made a mistake in my explanation. I amended the post above. Sorry about that. Please, if you find the time go through it again. You say you use column-major rather than row-major. The explanation I gave works for row-major so technically you will need to transpose the matrix. If other words for column major your matrix should be written with the basis vectors vertically:

|Rx Ux Fx|
M =|Ry Uy Fy| if you use column-major
|Rz Uz Fz|

Them matrix mult should be written as

|Rx Ux Fx| |Vx|
M * V = M =|Ry Uy Fy| * |Vy|
|Rz Uz Fz| |Vz|

For the right- left-hand naming convention I would also have a look at this page:

http://scratchapixel.com/lessons/3d-basic-lessons/lesson-4-geometry/math-operations-on-points-and-vectors/

Now from my understanding, there's a lot of people out there using different names for the same thing which is very confusing. That's why I like to refer to this page and try to stick to their convention which seems to be following some of the industry standards. Hopefully what's in their website is accurate and reliable ;-)

#2mast4as

Posted 08 January 2013 - 02:56 PM

Kevin by talking to the guys today I realised I made a mistake in my explanation. I amended the post above. Sorry about that. Please, if you find the time go through it again. You say you use column-major rather than row-major. The explanation I gave works for row-major so technically you will need to transpose the matrix. If other words for column major your matrix should be written with the basis vectors vertically:

 

   |Rx Ux Fx|

M =|Ry Uy Fy| if you use column-major

   |Rz Uz Fz| 

 

Them matrix mult should be written as

 

           |Rx Ux Fx|   |Vx|

M * V = M =|Ry Uy Fy| * |Vy|

           |Rz Uz Fz|   |Vz|


#1mast4as

Posted 08 January 2013 - 01:14 PM

Kevin

 

by talking to the guys today I realised I made mistake in my explanation. I amended the post above. Sorry about that.


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