Until now, the zbuffer was written straight from the internal zbuffer,
which has values that are inverse-proportional (like 1.0/z) which makes
it very hard to use it for postprocess, like zblur or other composit effects
that require Z.
Based on info from ILM, the values stored for Z in exr files is the
actual distance from a camera. I think that's about time to migrate to that
convention!
By default now, after render, the z values are converted to floats. This
saves in exr files now, but not in the Iris Z files. That latter was a
blender-only anyway, so might be not a real hassle to drop. :)
You can see the difference in the image window, but notice the range now
is linear mapped from camera clipstart to clipend.
Note; I just discover that ortho Z values need a different correction...
- images with a so-called "data window" (have negative start coordinate)
did not read correctly
- negative colors were not clamped yet in imbuf
Now there's still some compliancy issues with zbuffers... you can save
it either as unsigned int or as float, whilst blender renders zbuffer in
signed int. :)
- EXR now saves and reads Zbuffers correctly
- EXR reading didn't set alpha to 1 yet when no alpha buffer was present
- ImageWindow: the "black point" only checked for the r value... now is OK
- ImageWindow: Curves panal has button "reset"
- ImageWindow: hold LMB drag shows rgba and z values. With SHIFT or CTRL it
applies black/white point whilte dragging too
- ImageWindow: saving file copied the entire buffer... removed that. Also
made the header print clear; this save only saves in own file type.
- Curves: zoom and drag now gets clamped by the Clipping value
- Imbuf: duplicate buffer only copied one quarter of to new buffer
- Reading exr images now goes OK. I've unified the code for reading
'half' and 'float' (was nicely possible!). And removed useless copying
of data around.
- Fixed bug in allocating new rects, like for making mipmaps. flag issues.
- filter code accidentally incremented wrong pointer (crash on mipmap too)
- F10 scene buttons now has options "half" and "zbuf" for exr saving.
Note: when no float buffer is available, it always saves as "half",
that's sufficient anyway, since half is 16 bits per channel.
- EXR in imbuf now uses compliant ibuf->ftype flags for denoting exr
extensions such as 'half' and 'compression'.
- Removed ugly blenkernel dependency from exr module
Credits go to Gernot Ziegler, who originally coded EXR support, and to
Austin Benesh for bringing it further. Kent Mein provided a lot of code
for integrating float buffers in Blender imbuf and ImBuf API cleanup,
and provided Make and Scons and static linking.
At this moment; the EXR libraries are a *dependency*, so you cannot get
the Orange branch compiled without having OpenEXR installed. Get the
(precompiled or sources) stuff from www.openexr.com. Current default is
that the headers and lib resides in /user/local/
Several changes/additions/fixes were added:
- EXR code only supported 'half' format (16 bits per channel). I've added
float writing, but for reading it I need tomorrow. :)
- Quite some clumsy copying of data happened in EXR code.
- cleaned up the api calls already a bit, preparing for more advanced
support
- Zbuffers were saved 16 bits, now 32 bits
- automatic adding of .exr extensions went wrong
Imbuf:
- added proper imbuf->flags and imbuf->mall support for float buffers, it
was created for *each* imbuf. :)
- found bugs for float buffers in scaling and flipping. Code there will
need more checks still
- imbuf also needs to be verified to behave properly when no 32 bits
rect exists (for saving for example)
TODO:
- support internal float images for textures, backbuf, AO probes, and
display in Image window
Hope this commit won't screwup syncing with bf-blender... :/
