(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
