Re: [Openexr-devel] Invert lines during reading process ?

[Bob Friesenhahn]

The example at
http://www-h.eng.cam.ac.uk/help/tpl/graphics/using_glut.html seems to
include some clues.  It includes.

  glScalef(1, -1, 1);           /* Invert Y axis so increasing Y goes down. */
  glTranslatef(0, -h, 0);       /* Shift origin up to upper-left corner. */

Now I just need to try this out in my own little test program. :-)

Bob

On Sun, 4 Dec 2005, Gernot Ziegler wrote:

> Hej !
>
> OpenGL convention requires me to upload images upside down into the
> texture data buffer, that is, I need to read the EXR image from the bottom
> up - is there a way to do this more efficiently than to read the lines one
> by one (the headers lineorder attribute is only changeable for writing
> files, correct ?) ?
>
> If only the line-by-line reading remains:
> Should I maybe y-flip the data in main memory instead ? (Main memory is
> not an issue :-) )
>
> Servus,
>  Gernot
>
> --
> T----------------------------W-E-L-C-O-M-E------------------------------T
> O  The Austria <=> Sweden <=> Germany <=> Netherlands connection.....   H
> |  http://www.mpi-sb.mpg.de/~gziegler | http://www.lysator.liu.se/~gz   E
> \-----------------------------F-U-T-U-R-E-------------------------------/
>
>
> _______________________________________________
> Openexr-devel mailing list
> address@hidden
> http://lists.nongnu.org/mailman/listinfo/openexr-devel

======================================
Bob Friesenhahn
address@hidden, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/