the two files mikktspace.h and mikktspace.c. These are standalone files
which can be redistributed into any other application and regenerate the
same tangent spaces. The implementation is independent of the ordering
of faces and the vertex ordering of faces.
These should not have any effect on render results, except in some cases with
you have overlapping faces, where the noise seems to be slightly reduced.
There are some performance improvements, for simple scenes I wouldn't expect
more than 5-10% to be cut off the render time, for sintel scenes we got about
50% on average, that's with millions of polygons on intel quad cores. This
because memory access / cache misses were the main bottleneck for those scenes,
and the optimizations improve that.
Interal changes:
* Remove RE_raytrace.h, raytracer is now only used by render engine again.
* Split non-public parts rayobject.h into rayobject_internal.h, hopefully
makes it clearer how the API is used.
* Added rayintersection.h to contain some of the stuff from RE_raytrace.h
* Change Isect.vec/labda to Isect.dir/dist, previously vec was sometimes
normalized and sometimes not, confusing... now dir is always normalized
and dist contains the distance.
* Change VECCOPY and similar to BLI_math functions.
* Force inlining of auxiliary functions for ray-triangle/quad intersection,
helps a few percentages.
* Reorganize svbvh code so all the traversal functions are in one file
* Don't do test for root so that push_childs can be inlined
* Make shadow a template parameter so it doesn't need to be runtime checked
* Optimization in raytree building, was computing bounding boxes more often
than necessary.
* Leave out logf() factor in SAH, makes tree build quicker with no
noticeable influence on raytracing on performance?
* Set max childs to 4, simplifies traversal code a bit, but also seems
to help slightly in general.
* Store child pointers and child bb just as fixed arrays of size 4 in nodes,
nearly all nodes have this many children, so overall it actually reduces
memory usage a bit and avoids a pointer indirection.
Compositor: Texture node didn't use texture-nodes itself.
Now composites initialize texture nodes correctly.
Also reviewed the fix for crashing texture nodes for displace.
It appears texture nodes also are used for sculpt/paint
brushes, in these cases it can be allowed again. But, don't
do this during rendering for now!
* The problem is that shadow pass is derived from the diffuse pass as
shad = shad'/diff, where shad' = shad*diff. In cases where diff is
0 and the division can't be done shad is left as shad' (=0).
* This all works just fine until the diffuse color is 0 on just one
channel (no red in material color for example). In this case the shadow
pass is left as 0 too regardless of the existence of an actual shadow,
so the end result is a colored shadow!
* The only real solution is to use the original shadow intensity to
determine if there actually is a shadow or not. This is now stored in
shr->shad[3] from the lamp shadow calculation.
Note: The best solution would probably be to calculate the shadow pass on
it's own and not to derive it from the diffuse pass, but I didn't dare to
start messing up the shading code totally.
Now, rather than the bit-too-alarming stop sign, threaded wmJobs
display a progress indicator in the header. This is an optional feature
for each job type and still uses the same hardcoded ui template
(could use further work here...).
Currently implemented for:
Render - parts completed, then nodes comped
Compositor - nodes comped
Fluid Sim - frames simulated
Texture Bake - faces baked
Example: http://mke3.net/blender/devel/2.5/progress.mov
* Remove the manual OSA method but rather pass on derivatives to the
textures. This means that at the moment e.g. the bricks node is not
antialiased, but that image textures are now using mipmaps. Doing
oversampling on the whole nodetree is convenient but it is really
the individual textures that can do filtering best and quickest.
* Image textures in a texture node tree were not color corrected and
did not support 2d mapping, now it's passing along shadeinput to
make this possible. Would like to avoid this but not sure how.
* Fix preview not filling in all pixels when scaling or rotating in
the texture nodes.
Ambient occlusion: multiplied with direct lighting by default, add
is also still available and more blending methods might be added if
they are useful. This is fundamentally a non physical effect.
Environment lighting: always added as you would expect (though you can
subtract by specifying negative energy). This can be just white or take
colors or textures from the world.
Indirect lighting: only supported for AAO at the moment (and is still
too approximate), and also is always added. A factor is available to
specify how much is added, though value 1.0 is correct.
Also:
* Material ambient value now defaults to 1.0.
* Added Environment, Indirect and Emit pass.
* "Both" blending method is no longer available.
* Attenuation, sampling parameters are still shared, some could be split
up, though if they are different this would affect performance.
This brings back the single bounce indirect diffuse lighting for AAO,
it's not integrated well but that will be tackled later as part of
shading system refactor and subdivision changes. The caveats are the
same as AAO, with one extra thing, the diffuse lighting is sampled once
per face, so it will not be accurate unless faces are subdivided.
I'm committing this now so we can start testing it for Durian, and
since changes need to make it work properly are planned.
* Transparency is now it's own panel, with a boolean toggle
+ enum for z/ray transparency (following mockup made by
William). Also had to change DNA flags for this.
* Disabled radiosity a bit more in render engine, it still had
some effects like auto autosmooth.
* Make some sliders in material buttons percentages in RNA.
* Some other small tweaks in layout and naming.
Integration is still very rough around the edges and WIP, but it works, and can render smoke (using new Smoke format in Voxel Data texture) --> http://vimeo.com/6030983
More to come, but this makes things much easier to work on for me :)
*"Added" SCE_PASS_RAYHITS to visually see each pixel primitive and BB tests (not-completed for UI)
*Added runtime exchange of tree structure
*Removed FLOAT_EPSILON from BLI_bvhkdop BB's
svn merge https://svn.blender.org/svnroot/bf-blender/trunk/blender -r19820:HEAD
Notes:
* Game and sequencer RNA, and sequencer header are now out of date
a bit after changes in trunk.
* I didn't know how to port these bugfixes, most likely they are
not needed anymore.
* Fix "duplicate strip" always increase the user count for ipo.
* IPO pinning on sequencer strips was lost during Undo.
Robin (Frrr) Allen did a decent job on this, so we can also welcome him
as a member in the svn committers team to maintain it!
I do the first commit with some minor fixes:
- get Makefiles work
- fix rounding issue with tiles on unit faces
- removed UI includes from tex node
A nice doc in wiki is here:
http://wiki.blender.org/index.php/User:Frr/TexnodeManual
On the todo for Robin is:
- When using one or more Texture-input nodes, you cannot edit them by activating
(as works now for Material nodes).
- The new "output node" option fails on the default case, when only one
output node is active. It then shows often a blank menu. Will get fixed asap.
- When using a NodeTree-Texture as input node, the menu for 'active output'
should not show. NodeTree should ignore other nodetrees to keep things sane
for now.
- On a future todo is proper usage of "Dxt" and "Dyt" texture vectors for
superior antialising of checkers/bricks.
General note; I know people are dying to get a full integrated shader system
with nodes. In theory we could merge this with Material Nodetrees... but I
rather wait for a solid and very well thought out design proposal for this,
also including design ideas for unifying with a shader language (GPU, CPU).
For the time being this is a nice extension of current textures. :)
This was a bit complicated to do, but is working pretty well now, and can make shading significantly faster to render.
This option pre-calculates self-shading information into a
3d voxel grid before rendering, then uses and interpolates
that data during the main rendering phase, rather than
calculating shading for each sample. It's an approximation
and isn't as accurate as getting the lighting directly,
but in many cases it looks very similar and renders much faster.
The voxel grid covers the object's 3D screen-aligned bounding box
so this may not be that useful for large volume regions like a
big range of cloud cover, since you'll need a lot of resolution.
The render time speaks for itself here:
http://mke3.net/blender/devel/rendering/volumetrics/vol_light_cache_interpolation.jpg
The resolution is set in the volume panel - it's the resolution
of one edge of the voxel grid. Keep in mind that the higher the
resolution, the more memory needed, like in fluid sim. The
memory requirements increase with the cube of the edge
resolution so be careful. I might try and add a little memory
calculator thing like fluid sim has there later.
The voxels are interpolated using trilinear interpolation -
here's a comparison image I made during testing:
http://mke3.net/blender/devel/rendering/volumetrics/vol_light_cache_compare.jpg
There might still be a couple of little tweaks I can do to
improve the visual quality, I'll see.
due to jittering of the start position for antialiasing in a pixel.
Now it distributes the start position over the fixed osa sample
positions, instead of of random positions in space. The ugly bit is
that a custom ordering was defined for osa 8/11/16 to ensure that the
first 4 are distributed relatively fair for adaptive sampling to decide
if more samples need to be taken.
Otherwise known as a phase function, this determines in which directions
the light is scattered in the volume. Until now it's been isotropic
scattering, meaning that the light gets scattered equally in all
directions. This adds some new types for anisotropic scattering, to
scatter light more forwards or backwards towards the viewing direction,
which can be more similar to how light is scattered by particles in nature.
Here's a diagram of how light is scattered isotropically and anisotropically:
http://mke3.net/blender/devel/rendering/volumetrics/phase_diagram.png
The new additions are:
- Rayleigh
describes scattering by very small particles in the atmosphere.
- Mie Hazy / Mie Murky
more generalised, describes scattering from large particle sizes.
- Henyey-Greenstein
a very flexible formula, that can be used to simulate a wide range of
scattering. It uses an additional 'Asymmetry' slider, ranging from -1.0
(backward scattering) to 1.0 (forward scattering) to control the
direction of scattering.
- Schlick
an approximation of Henyey-Greenstein, working similarly but faster.
And a description of how they look visually (just an omnidirectional lamp
inside a volume box)
http://mke3.net/blender/devel/rendering/volumetrics/phasefunctions.jpg
* Sun/sky integration
Volumes now correctly render in front of the new physical sky. Atmosphere
still doesn't work correctly with volumes, due to something that i hope
can be fixed in the atmosphere rendering, but the sky looks quite good.
http://mke3.net/blender/devel/rendering/volumetrics/sky_clouds.png
This also works very nicely with the anisotropic scattering, giving
clouds their signature bright halos when the sun is behind them:
http://mke3.net/blender/devel/rendering/volumetrics/phase_cloud.mov
in comparison here's a render with isotropic scattering:
http://mke3.net/blender/devel/rendering/volumetrics/phase_cloud_isotropic.png
* Added back the max volume depth tracing limit, as a hard coded value -
fixes crashes with weird geometry, like the overlapping faces around
suzanne's eyes. As a general note, it's always best to use volume
materials on airtight geometry, without intersecting or overlapping faces.
solids, in front of other volumes, etc. Now there's a 'layer depth'
value that works similarly to refraction depth - a limit for how many
times the view ray will penetrate different volumetric surfaces.
I have it close to being able to return alpha, but it's still not 100%
correct and needs a bit more work. Going to sit on this for a while.
but only when the UV's are connected. That fixes some artifacts when
baking and using tangent space normal maps. It does mean increased
memory usage because it now stores 4 tangents per face like UV's,
and increased processing time, but there's no simple way around that.
This completes the pipeline make-over, as started in 2006. With this
option, during rendering, each sample for every layer and pass is being
saved on disk (looks like non-antialiased images). Then the composite
and color correction happens, then a clip to 0-1 range, and only in end
all samples get combined - using sampling filters such as gauss/mitch/catmul.
This results in artefact-free antialiased images. Even Z-combine or
ID masks now work perfect for it!
This is an unfinished commit btw; Brecht will finish this for strands.
Also Halo doesnt work yet.
To activate FSA: press "Save Buffers" and the new button next to it. :)
This is actually just the alpha value as currently being calculated
by the mist code. It is in many cases not very useful to have this as
alpha in shading result, also for postprocess and composite.
Note: this pass also works with "Mist" not set in World, of course.
=============================
A new approximate ambient occlusion method has been added, next to the
existing one based on raytracing. This method is specifically targetted
at use in animations, since it is inherently noise free, and so will
not flicker across frames.
http://www.blender.org/development/current-projects/changes-since-244/approximate-ambient-occlusion/http://peach.blender.org/index.php/approximate-ambient-occlusion/
Further improvements are still needed, but it can be tested already. There
are still a number of known issues:
- Bias errors on backfaces.
- For performance, instanced object do not occlude currently.
- Sky textures don't work well, the derivatives for texture evaluation
are not correct.
- Multiple passes do not work entirely correct (they are not accurate
to begin with, but could be better).
====================
- "From Dupli" option for orco and uv texture coordinates. For dupliverts,
duplifaces and dupli particles, this uses the orco and uv at the point
on the parent surface. Can for example be used for texturing feathers
and leafs. Note that uv only works for duplifaces and particles emitted
from faces, these are not defined at vertices.
- "Width Fade" option for strand render, to fade out along the width of the
strand. Committing this so it can be tested, might be changed or removed
even, if it doesn't give nice results.
=================
Big commit, but little user visible changes.
- Dupliverts and duplifaces are now rendered as instances, instead
of storing all of the geometry for each dupli, now an instance is
created with a matrix transform refering to the source object.
This should allow us to render tree leaves more memory efficient.
- Radiosity and to some degree raytracing of such objects is not
really efficient still. For radiosity this is fundamentally hard
to solve, but raytracing an octree could be created for each object,
but the current octree code with it's fixed size doesn't allow this
efficiently.
- The regression tests survived, but with I expect that some bugs will
pop up .. hopefully not too many :).
Implementation Notes
====================
- Dupligroups and linked meshes are not rendered as instances yet,
since they can in fact be different due to various reasons,
instancing of these types of duplis that are the same can be added
for them at a later point.
- Each ObjectRen now stores it's own database, instead of there being
one big databases of faces, verts, .. . Which objects that are actually
rendered are defined by the list of ObjectRenInstances, which all refer
to an ObjectRen.
- Homogeneous coordinatess and clipping is now not stored in vertices
anymore, but instead computed on the fly. This couldn't work for
instances. That does mean some extra computation has to be done, but
memory lookups can be slow too, and this saves some memory. Overall
I didn't find a significant speed impact.
- OSA rendering for solid and ztransp now is different. Instead of e.g.
going 8 times over the databases times and rendering the z-buffer, it
now goes over the database once and renders each polygon 8 times. That
was necessary to keep instances efficient, and can also give some
performance improvement without instances.
- There was already instancing support in the yafray export code, now it
uses Blender's render instances for export.
- UV and color layer storage in the render was a bit messy before, now
should be easier to understand.
- convertblender.c was reorganized somewhat. Regular render, speedvector
and baking now use a single function to create the database, previously
there was code duplicated for it.
- Some of these changes were done with future multithreading of scene
and shadow buffer creation in mind, though especially for scene creation
much work remains to be done to make it threadsafe, since it also involves
a lot of code from blenkernel, and there is an ugly conflict with the way
dupli groups work here .. though in the render code itself it's almost there.
editmode was not exited, and vertex normals would not write at all! (probably own error)
- Edited tooltip for texture DVar (was some user confusion in the studio as to its purpose)
- Set render border is disabled when it has no area - so drawing a box outside the camera disables .
=========
- Fix crash in particle transform with the particle system not editable.
- Particle child distribution and caching is now multithreaded.
- Child particles now have a separate Render Amount next to the existing
Amount. The render amount particles are now only distributed and cached
at render time, which should make editing with child particles faster.
- Two new options for diffuse strand shading:
- Surface Diffuse: computes the strand normal taking the normal at
the surface into account.
- Blending Distance: the distance in Blender units over which to
blend in the normal at the surface.
- Special strand rendering for more memory efficient and faster hair and
grass. This is a work in progress, and has a number of known issues,
don't report bugs to me for this feature yet.
More info:
http://www.blender.org/development/current-projects/changes-since-244/particles/
=============
A new "Selected to Active" option in the Bake panel, to (typically) bake
a high poly object onto a low poly object. Code based on patch #7339 by
Frank Richter (Crystal Space developer), thanks!.
Normal Mapping
==============
Camera, World, Object and Tangent space is now supported for baking, and
for material textures. The "NMap TS" setting is replaced with a dropdown
of the four choices in the image texture buttons.
http://www.blender.org/development/current-projects/changes-since-244/render-baking/
This is an additional option for 'TexFace', which uses the alpha of
the UV assigned faces as well as the colour. It appears in material
buttons as a little 'A' button next to 'TexFace', when 'TexFace is
switched on. It's a bit horrible, but no point tweaking that layout in
isolation at this stage.
This image is using texface alpha, with different assigned images, all
sharing the one material:
http://mke3.net/blender/devel/rendering/texface_alpha.jpg
Usually I consider texface (and teaching people to use it for UV
mapping) to be pretty evil, but in some cases, when you have lots of
separate images that you want to control in the one material, it can
be quite handy.
* Geometry node: Front/back output
This is used as a mask for determining whether you're looking at the front side or back side of a mesh, useful for blending materials, my practical need was giving different materials to the pages of a magazine: http://mke3.net/blender/etc/frontback-h264.mov
Give 1.0 if it's the front side, and 0.0 if it's the back side.
* Extended material node
This is the same as the material node, but gives more available inputs and outputs, (basically just connecting up more of ShadeInput and ShadeResult to the node). I didn't want to add it to the normal simple Material node since you don't always need all that stuff, and it would make the node huge, but when you do need it, it's nice to have it.
== Comp nodes ==
* Invert node
Inverting is something that happens all the time in a node setup, and this makes it easier. It's been possible to invert previously by adding a mix node and subtracting the input from 1.0, but it's not the best way of doing it. This node:
- makes it a lot faster to set up, rather than all the clicking required with the mix node
- is a lot more usable amidst a complex comp setup, when you're looking at a node tree, it's very helpful to be able to see at a glance what's going on. Using subtract for inverting is easily mixed up with other nodes in which you are actually subtracting, not inverting, and looks very similar to all the other mix nodes that usually litter a comp tree.
- has options to invert the RGB channels, the Alpha channel, or both. This saves adding lots of extra nodes (separate RGBA, subtract, set alpha) when you want to do something simple like invert an alpha channel. I'd like to add this option to other nodes too.
There's also a shader node version too.
* Also a few fixes that I committed ages ago, but seems to have been overwritten in Bob's node refactor:
- adding new compbufs to the set alpha and alphaover nodes when you have only one noodle connected to the lower input
- making the fac value on RGB curves still work when there's nothing connected to it
Added support for multiple UVs in the render engine. This also involved
changing the way faces are stored, to allow data to be added optionally
per 256 faces, same as the existing system for vertices.
A UV layer can be specified in the Map Input panel and the Geometry node
by name. Leaving this field blank will default to the active UV layer.
Also added sharing of face selection and hiding between UV layers, and at
the same time improved syncing with editmode selection and hiding.
Still to do:
- Multi UV support for fastshade.
- Multires and NMesh preservation of multiple UV sets.
- Bug: material emit was ignored (showed in preview render backdrop)
- Bug: world exposure was ignored
- Bug: lamp halo was ignoring 'render layer light override'.
Further reshuffled the way shadows are being pre-calculated, this to enable
more advanced (and faster) usage of Material lightgroups. Now shadows are
being cached in lamps, using a per-sample counter to check if a recalc is
needed. Will also work (later) for Raytracing node shaders.
- New: Material LightGroup option "Always", which always shades the lights
in the group, independent of visibility layer. (so it allows to move such
lights to hidden layer, not influencing anything).
Full log:
http://www.blender3d.org/cms/Render_Passes.829.0.html
In short:
- Passes now have option to be excluded from "Combined".
- RenderLayers allow to override Light (Lamp groups) or Material.
- RenderLayers and Passes are in Outliner now, (ab)using Matt's nice
'restriction collumns'. :)
- Crash, caused by commit of 1 hour ago to fix 'All Z' render problem
- Bug: yesterday's fix for node material renders caused some issues with
precalculating correct shadow.
- Composite Translate node: input sockets allowed multiple inputs
