- Live scanline updates while rendering
Using a timer system, each second now the tiles that are being processed
are checked if they could use display.
To make this work pretty, I had to use the threaded 'tile processor' for
a single thread too, but that's now proven to be stable.
Also note that these updates draw per layer, including ztransp progress
separately from solid render.
- Recode of ztransp OSA
Until now (since blender 1.0) the ztransp part was fully rendered and
added on top of the solid part with alpha-over. This adding was done before
the solid part applied sub-pixel sample filtering, causing the ztransp
layer to be always too blurry.
Now the ztransp layer uses same sub=pixel filter, resulting in the same
AA level (and filter results) as the solid part. Quite noticable with hair
renders.
- Vector buffer support & preliminary vector-blur Node
Using the "Render Layer" panel "Vector" pass button, the motion vectors
per pixel are calculated and stored. Accessible via the Compositor.
The vector-blur node is horrible btw! It just uses the length of the
vector to apply a filter like with current (z)blur. I'm committing it anyway,
I'll experiment with it further, and who knows some surprise code shows up!
-> Rendering in RenderLayers
It's important to distinguish a 'render layer' from a 'pass'. The first is
control over the main pipeline itself, to indicate what geometry is being
is rendered. The 'pass' (not in this commit!) is related to internal
shading code, like shadow/spec/AO/normals/etc.
Options for RenderLayers now are:
- Indicate which 3d 'view layers' have to be included (so you can render
front and back separately)
- "Solid", all solid faces, includes sky at the moment too
- "ZTransp", all transparent faces
- "Halo", the halos
- "Strand", the particle strands (not coded yet...)
Currently only 2 'passes' are exported for render, which is the "Combined"
buffer and the "Z. The latter now works, and can be turned on/off.
Note that all layers are still fully kept in memory now, saving the tiles
and layers to disk (in exr) is also todo.
-> New Blur options
The existing Blur Node (compositor) now has an optional input image. This
has to be a 'value buffer', which can be a Zbuffer, or any mask you can
think of. The input values have to be in the 0-1 range, so another new
node was added too "Map Value".
The value input can also be used to tweak blur size with the (todo)
Time Node.
Temporal screenies:
http://www.blender.org/bf/rt.jpghttp://www.blender.org/bf/rt1.jpghttp://www.blender.org/bf/rt2.jpg
BTW: The compositor is very slow still, it recalulates all nodes on each
change still. Persistant memory and dependency checks is coming!
A full detailed description of this will be done later... is several days
of work. Here's a summary:
Render:
- Full cleanup of render code, removing *all* globals and bad level calls
all over blender. Render module is now not called abusive anymore
- API-fied calls to rendering
- Full recode of internal render pipeline. Is now rendering tiles by
default, prepared for much smarter 'bucket' render later.
- Each thread now can render a full part
- Renders were tested with 4 threads, goes fine, apart from some lookup
tables in softshadow and AO still
- Rendering is prepared to do multiple layers and passes
- No single 32 bits trick in render code anymore, all 100% floats now.
Writing images/movies
- moved writing images to blender kernel (bye bye 'schrijfplaatje'!)
- made a new Movie handle system, also in kernel. This will enable much
easier use of movies in Blender
PreviewRender:
- Using new render API, previewrender (in buttons) now uses regular render
code to generate images.
- new datafile 'preview.blend.c' has the preview scenes in it
- previews get rendered in exact displayed size (1 pixel = 1 pixel)
3D Preview render
- new; press Pkey in 3d window, for a panel that continuously renders
(pkey is for games, i know... but we dont do that in orange now!)
- this render works nearly identical to buttons-preview render, so it stops
rendering on any event (mouse, keyboard, etc)
- on moving/scaling the panel, the render code doesn't recreate all geometry
- same for shifting/panning view
- all other operations (now) regenerate the full render database still.
- this is WIP... but big fun, especially for simple scenes!
Compositor
- Using same node system as now in use for shaders, you can composit images
- works pretty straightforward... needs much more options/tools and integration
with rendering still
- is not threaded yet, nor is so smart to only recalculate changes... will be
done soon!
- the "Render Result" node will get all layers/passes as output sockets
- The "Output" node renders to a builtin image, which you can view in the Image
window. (yes, output nodes to render-result, and to files, is on the list!)
The Bad News
- "Unified Render" is removed. It might come back in some stage, but this
system should be built from scratch. I can't really understand this code...
I expect it is not much needed, especially with advanced layer/passes
control
- Panorama render, Field render, Motion blur, is not coded yet... (I had to
recode every single feature in render, so...!)
- Lens Flare is also not back... needs total revision, might become composit
effect though (using zbuffer for visibility)
- Part render is gone! (well, thats obvious, its default now).
- The render window is only restored with limited functionality... I am going
to check first the option to render to a Image window, so Blender can become
a true single-window application. :)
For example, the 'Spare render buffer' (jkey) doesnt work.
- Render with border, now default creates a smaller image
- No zbuffers are written yet... on the todo!
- Scons files and MSVC will need work to get compiling again
OK... thats what I can quickly recall. Now go compiling!
- Image textures use float colors now, when present. Works for mipmap too,
and for AO skycolor (probes)
- Backbuffer option uses float buffers too. Note that rendering OSA will
resample the backbuffer, filtering it... will need to be solved with the
new composit stage
- LMB sampling in image window now shows float color too
+ bugfix in imbuf, filtering for float buffers had an error.
(WIP, don't bugs for this in tracker yet please!)
- New Panel "Layers" in Material buttons, allows to add unlimited amount
of materials on top of each other.
- Every Layer is actually just another Material, which gets rendered/shaded
(including texture), and then added on top of previous layer with an
operation like Mix, Add, Mult, etc.
- Layers render fully independent, so bumpmaps are not passed on to next
layers.
- Per Layer you can set if it influences Diffuse, Specular or Alpha
- If a Material returns alpha (like from texture), the alpha value is
used for adding the layers too.
- New texture "Map To" channel allows to have a texture work on a Layer
- Each layer, including basis Material, can be turned on/off individually
Notes:
- at this moment, the full shading pass happens for each layer, including
shadow, AO and raytraced mirror or transparency...
- I had to remove old hacks from preview render, which corrected reflected
normals for preview texturing.
- still needs loadsa testing!
I've been going over the zbuf.c code, which is indeed very ancient,
with a load of old optimizing and redundant code in use.
Added more 'modern' Span support, which fills per face two arrays
with the scanline information in it. That way you can zbuffer a quad in one
run as well. It was also exactly that code that's copied all over in zbuf.c
For now, to prevent issues for the release, the 'render a quad in 1 run' is
only in use for the strand render. Tests reveil a speedup of about 33%.
Will work on this recode later... which would also result in making zbuf.c
threadsafe.
And: bugfix #3398
When using the new 'render emitter' for particles, the orco array for
particles was accidentally used by mesh too.
- The ortho render recode had a weak method to calculate the Z value of the
render coordinate (shi.co[2]). Worked OK for normal render, but not in
unified, giving big errors in Ortho Unfied render.
Solved with proper math, using face equation a*x+b*y+c*y=d. Dunno why I
didn't do it in first place. :)
- Bug fix#2493. Edge render gave much different result for Ortho. This
was due to overflows in the integer math filtering zbuffer values.
Cleaned it op properly, preventing any integer overflow now.
submitted by Alexander, changes/improvements are:
- Moved to new Panel in Scene buttons "Post Effects". Together with other
postprocessing options, such as Edge render. It is also not called DoF,
this because that's a bit pretending too much then. It's a zblur still!
- Made it render Alpha as well
- Made it use and deliver float buffers
- Huge cleanup of zblur.c code, was very messy. It was alling things in render
code without need even (win matrices, transform faces, etc)
- Fixed errors in using Z values (zbuffer is signed int)
- Removed very weird gamma corrections for front/back half
- Tweaked gaussian table, allow variable 'Sigma' to be set for gauss curve
- Didn't copy 'auto focus' yet. Use of this is very limited, and gives
false expectations, nor works for rendering anims with deamons well.
Main issue remains: it's not a very advanced feature... I still doubt
very much if this deserves to be released. Spent 2 days on trying to get
the key issues solved, with not much results.
- gauss filter code has weird side effects on large blur size
- having unsharp (blurred) in front also blurs what's around in back.
only blurred in back with sharp in front works a little bit
- severe aliasing errors... also due the code splitting in 2 halves
- doesnt work with unified yet
- won't work for halos, spot halos or transparant faces
Anyhoo... It was promised to be committed, so now artists can play with it.
Who knows it's useful after all, or some fixes can be implemented. :)
- Maximum faces/halos per pixel was 500, which wasn't correctly applied in
all cases, causing errors in AA
- Moved maximum up to 1000 now
- made halos become clipped away from filling in buffers when behind a
solid face. That saves a lot of rendertime!
Unified remains weak with halos...
- removed ugly pointerhack from OSA render (negative indices denoted
pointers). this should solve memory errors when using >1.5 gig mem
- cleaned up usage of zbuffer values. These are signed in Blender, and
treated as unsigned all over, giving confusing code
- fixed incorrect gamma-adding for halos (caused in after xmas commit)
And bugfix #2101; wire render didn't give correct rendering for mist.
This caused by fact wires are 2D pixel lines, and not correctly filled
in faces. Retrieving the 3d coordinate while render cannot use a face-
equation then. Solved by retrieving 3D coordinate based on zbuffer value.
Still todo here: calculating correct texture coordinates for wire-edges
that are no faces.
Alpha for halos was always added, even when "Add" slider was zero. Fixed.
(also; made BROW define BROW16, to distinguish from int version in
BKE_utildefines.h)
- zbuf; error caused by using unsigned int as counter (while >= 0) in radio
- backbuffer didnt load in initrender (was removed from sky render)
- unitialized variable in envmap.c
Render:
- New; support for dual CPU render (SDL thread)
Currently only works with alternating scanlines, but gives excellent
performance. For both normal render as unified implemented.
Note the "mutex" locks on z-transp buffer render and imbuf loads.
- This has been made possible by major cleanups in render code, especially
getting rid of globals (example Tin Tr Tg Tb Ta for textures) or struct
OSA or using Materials or Texture data to write to.
- Made normal render fully 4x32 floats too, and removed all old optimizes
with chars or shorts.
- Made normal render and unified render use same code for sky and halo
render, giving equal (and better) results for halo render. Old render
now also uses PostProcess options (brightness, mul, gamma)
- Added option ("FBuf") in F10 Output Panel, this keeps a 4x32 bits buffer
after render. Using PostProcess menu you will note an immediate re-
display of image too (32 bits RGBA)
- Added "Hue" and "Saturation" sliders to PostProcess options
- Render module is still not having a "nice" API, but amount of dependencies
went down a lot. Next todo: remove abusive "previewrender" code.
The last main global in Render (struct Render) now can be re-used for fully
controlling a render, to allow multiple "instances" of render to open.
- Renderwindow now displays a smal bar on top with the stats, and keeps the
stats after render too. Including "spare" page support.
Not only easier visible that way, but also to remove the awkward code that
was drawing stats in the Info header (extreme slow on some ATIs too)
- Cleaned up blendef.h and BKE_utildefines.h, these two had overlapping
defines.
- I might have forgotten stuff... and will write a nice doc on the architecture!
Gaussian sampling/rendering now supported too!
Also corrected gamma corrected adding of colors, which gives better alpha
and blending with sky than normal render does. The latter I could check
once too...
When tracing a mirror with AO, the rendering was extremely slow due to
each mirror sample (like 8 per pixel) taking a full range of AO samples.
Now it uses for mirror samples a corrected amount, which makes sure for
a single pixel still a full AO range is used.
Makes mirror+AO render 5-6 times faster, at least.
- Ambient Occlusion is a more sophisticated ambient trick, which takes
nearby faces into account by firing a hemisphere of shadow-rays
around. AKA 'dirt shader'.
- Eeshlo made it a Lamp type, which doesn't fit well. I've moved the
settings to the World menu, and let the Material->ambient value control
the amount it contributes
- currently, the AO value is added/subtracted/mixed with the 'diffuse'
factor while shading, before it is multiplied with Material color
Buttons are in new Panel 'Amb Occ" in F8 menu. Note:
- "Dist:" by shortening the length of rays you get subtler effects and it
renders faster too
- "DistF:" the attennuation factor gives control over how the 'shadow'
spreads out.
Further it's just raytracing, so tends to be slooooow.... :)
Here same tricks as for other raytraced scenes apply, especially try to
keep the environment as small as possible (exclude faces from Octree by
giving them no Material Traceable).
I still have to think over a couple of aspects, will await feedback on it:
- AO color? Now it just adds 'white'
- other sampling patterns? I tried dithering, which was so-so
- method of controlling final 'samples' in F10? Might be useful for other
oversampling too (area light) to have it reacting to a percentage or so..
(1 lamp, shadow). The 'coherence' check gets reset now for each new
pixel rendered, which remains efficient for oversampling.
- small cleanups in code, prototype added, less globals.
already gave noise with area size of 0.1.
Limited buttons to minimum value of 0.01 for area light. For people
who want smaller they can scale it down in 3d, effectively reducing
the energy then as well.
At last irc meeting, eeshlo pointed to an error in the code. It didn't
use the IOR value correctly. This has been solved. So how it works now:
- the IOR button value influences (very subtle) the fresnel effect.
Only for realism diehards.
- the Fresnel value (slider) now denotes the power in the function
rf + (1-rf) * (1-c)^5
where rf= rf = ((ior-1)/(ior+1))^2
and c the dot-product ray/normal.
- so, set the slider at '5' and you have real fresnel. Lower values
for interesting artistic effects.
- put back the forgotten code for gaussian corrected sampling during
antialising render. Normally, each sub-pixel sample in Blender counts
equally, and together make up the pixel color.
With 'Gauss' option set (F10 menu) each sub-pixel sample creates a small
weighted mask with variable size, which (can) affect neighbouring pixels
as well. The result is smoother edges, less sensitive for gamma, and
well suited to reduce motion-aliasing (when things move extreme slow).
This is result of *long* period of research in NeoGeo days, and based on
every scientific sampling/reconstructing theory we could find. Plus a
little bit of our selves. :)
- I should write once how blender constructs Jitter tables for sub-sampling.
this is a very nice method, and superior to normal block filter or random
jittering... time!
Main target was to make the inner rendering loop using no globals anymore.
This is essential for proper usage while raytracing, it caused a lot of
hacks in the raycode as well, which even didn't work correctly for all
situations (textures especially).
Done this by creating a new local struct RenderInput, which replaces usage
of the global struct Render R. The latter now only is used to denote
image size, viewmatrix, and the like.
Making the inner render loops using no globals caused 1000s of vars to
be changed... but the result definitely is much nicer code, which enables
making 'real' shaders in a next stage.
It also enabled me to remove the hacks from ray.c
Then i went to the task of removing redundant code. Especially the calculus
of texture coords took place (identical) in three locations.
Most obvious is the change in the unified render part, which is much less
code now; it uses the same rendering routines as normal render now.
(Note; not for halos yet!)
I also removed 6 files called 'shadowbuffer' something. This was experimen-
tal stuff from NaN days. And again saved a lot of double used code.
Finally I went over the blenkernel and blender/src calls to render stuff.
Here the same local data is used now, resulting in less dependency.
I also moved render-texture to the render module, this was still in Kernel.
(new file: texture.c)
So! After this commit I will check on the autofiles, to try to fix that.
MSVC people have to do it themselves.
This commit will need quite some testing help, but I'm around!
- implemented tracing of transparency for shadows. This is a material
option, in the new RayTrace panel.
it only traces color and alpha, not shading. So the results of some
transparant colored unlit faces can look odd. I will look onto that.
- changed fresnel formula (got hint from eeshlo!). this simplifies the UI,
now only one button needed. The fresnel value "should" be identical as
the refraction index, but that is booooring! So i added a special fresnel
refraction slider for both mirroring and transparency. By setting all 3
sliders equal, you get 'realism'.
- fresnel for transparancy works for Ztra rendering too. Same for transpa-
rent shadow. But then you need to set 'ray' on in F10 menu.
- uploaded new monkey_glass blend in download.blender.org/demo/test/
Next stage: killing the globals from render, and implement "translucency"
which is effectively allowing faces being lit from behind, as paper or
cloth.
Changelog:
- enable refraction with button "Ray Transp" in Material buttons.
- set "Angular Index" value for amount of refraction.
- use the "Alpha" value to define transparency.
- remember to set a higher "Depth" too... glass can bounce quite some
more than expected.
- for correct refraction, 3D models MUST have normals pointing in the
right direction (consistently pointing outside).
- refraction 'sees' the thickness of glass based on what you model. So
make for realistic glass both sides of a surface.
- I needed to do some rewriting for correct mirroring/refraction,
especially to prevent specularity being blended away.
Solved this with localizing shading results in the rendercore.c.
Now specularity correctly is added, and reduces the 'mirror' value.
- Localizing more parts of the render code is being planned. The old
render heavily relies on struct Render and struct Osa to store globals.
For scanline render no problem, but recursive raytracing dislikes that.
- done test with gamma-corrected summation of colors during tracing, is
commented out still. But this will give more balanced reflections. Now
dark reflections that are reflected in a bright surface seem incorrect.
- Introduced 'Fresnel' effect for Mirror and Transparency. This
influences the amount of mirror/transparency based at viewing angle.
Next to a new Fresnel slider, also a 'falloff' button has been added to
define the way it spreads.
- Fresnel also works for Ztransp rendering
- created new Panel for Raytrace options
I have to evaluate still where it all should be logically located.
- material preview shows fake reflection and fake refraction as well.
This is a revision of the old NeoGeo raytracer, dusted off, improved quite
a lot, and nicely integrated in the rest of rendering pipeline.
Enable it with F10-"Ray", and set either a 'ray-shadow' lamp or give the
Material a "RayMirror" value.
It has been added for 2 reasons:
- get feedback on validity... I need artists to play around with it if it's
actually useful. It still *is* raytracing, meaning complex scenes will
easily become slow.
- for educational purposes. All raytracing happens in ray.c, which can be
quite easily adjusted for other effects.
When too many disasters pop up with this, I'll make it a compile #ifdef.
But so far, it seems to do a decent job.
Demo files: http://www.blender.org/docs/ray_test.tgz
An article (tech) about how it works, and about the new octree invention
will be posted soon. :)
Note: it doesn't work with unified render yet.
do a make clean in source/blender/ to be sure!
- Included the new shaders from Cessen... well, only the shader calls
themselves. To make sure the shaders work I nicely integrated it
- MaterialButtons: layout changed a bit, but still resembles the old
layout. The 'shader' options now are located together.
- Shaders are separated in 'diffuse' and 'specular'. You can combine them
freely.
- diffuse Lambert: old shader
diffuse Oren Nayar: new shader, gives sandy/silky/skinny material well
diffuse Toon: for cartoon render
- specular Phong: new spec, traditional 70ies spec
specular CookTorr: a reduced version of cook torrance shading, does
off specular peak well
specular Blinn: new spec, same features as CookTorr, but with extra
'refraction' setting
specular Toon: new spec for cartoon render
- default blender starts with settings that render compatible!
- works in shaded view and preview-render
- works in unified render
Further little changes:
- removed paranoia compile warnings from render/loader/blenlib
- and the warnings at files I worked at were removed.
(adding)
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
also the Makefile.in's were from previous patch adding
the system depend stuff to configure.ac
Kent
--
mein@cs.umn.edu
