[x3d-public] Row/column-order in the SFMatrix*, MFMatrix* fields, I think X3DOM reading order contrasts to what spec says

[Holger Seelig]

Michalis,

I think you are making a mistake. X3D matrices are in row-major fashion. From the current X3D4.0 standard: 

SFMatrix4d matrices are organized in row-major fashion. The first row of the matrix stores information for the x dimension, the second for the y dimension, and the third for the z dimension. Since these data types are commonly used for 3D transformation matrices, translation values are stored in the fourth row.

This means the matrix should be:

 matrix
    1 0 0 0
    0 1 0 0
    0 0 1 0
    1 2 3 1

The translation values are now in the last row as required by the standard.

See also:
https://www.web3d.org/specifications/X3Dv4Draft/ISO-IEC19775-1v4.1-CD/Part01/fieldTypes.html#SFMatrix4dAndMFMatrix4d

https://en.wikipedia.org/wiki/Row-_and_column-major_order

Best regards,
Holger

—
Holger Seelig
holger.seelig at yahoo.de


> Am 23.11.2025 um 01:38 schrieb Michalis Kamburelis via x3d-public <x3d-public at web3d.org>:
> 
>  matrix
>     1 0 0 1
>     0 1 0 2
>     0 0 1 3
>     0 0 0 1
> 

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