CHANGELOG

YafaRay Core code ChangeLog
===========================
Important: read the README file for installation instructions and important information about YafaRay

This is an abbreviated list of changes. The full/detailed list of changes can be seen at:
* YafaRay Core code: https://github.com/YafaRay/Core/commits/master


YafaRay (development v3.x.x, work in progress)
----------------------------------------------
Feature changes/additions:
--------------------------
* New per-material transparency bias for Shiny Diffuse. When there are objects with many transparent surfaces stacked close together (such as leaves in a tree) sometimes black artifacts appear if the ray reaches the maximum depth. This can be solved by increasing the maximum ray depth, but the render times increase. I've added two new parameters for the Shiny Diffuse material to try to achieve a "trick", which is not realistic and may cause other artifacts but that should prevent the black areas without having to increase the maximum ray depth so much.

Dependencies changes:
---------------------
* IMPORTANT: Migration from Qt4 to Qt5 as Qt4 reached End of Life
* Dependency on meganz/mingw-std-threads made optional, because it's needed for old MinGW compilers but it causes conflicts with new MinGW compilers, so better to have it as an option in CMake (disabled by default)

Other changes:
----------
* Silenced some warnings while building in recent versions of gcc.


YafaRay v3.3.0 (2017-08-22)
---------------------------

Feature changes/additions:
--------------------------
* "Flat Material" option added to Shiny Diffuse, requested by a certain user. Flat Material is a special non-photorealistic material that does not multiply the surface color by the cosine of the angle with the light, as happens in real life. Also, if receive_shadows is disabled, this flat material does no longer self-shadow. For special applications only.

Bug fixes:
----------
* Bidirectional: fixed transparent background not working, was causing the entire render to have transparent alpha. See: http://www.yafaray.org/community/forum/viewtopic.php?f=15&t=5236
* Bidirectional: fixes (horrible hacks in fact, but...) for unitialized values causing incorrect illumination in scenes
* Fixed hang in Windows 7 when YafaRay is built using Visual Studio 2013.
* Some building fixes


YafaRay v3.2.0 (2017-03-21)
---------------------------

Feature changes/additions in v3.2.0:
------------------------------------
* IMPORTANT: Support for Texture Mipmaps / Ray Differentials, see: http://yafaray.org/node/695
    - Modifier all ImageHandlers to standardise access and make them more flexible. BIG changes to ImageHandlers.
    - Added new Grayscale internal buffers (optional)
    - Reorganized all Interpolation and GetColor code
    - Added MipMap capability to ImageHandlers
    - Added Trilinear MipMap interpolation based on Ray Differentials.
    - Added EWA MipMap interpolation based on Ray Differentials
    - Heavily modified IBL blur function, to use mipmaps with manually calculated mipmap level instead of the previous dedicated "IBL blur" process

* Path Tracing integrator: added new Russian Roulette parameter to speed up path tracing, see: http://www.yafaray.org/node/775
    The relevant parameter will be "russian_roulette_min_bounces".
    - If this parameter is set to 0, russian roulette will be enabled.
    - If set to the same value specified in depth (max bounces), russian roulette will be disabled
    - If set to a value between 0 and max bounces, then russian roulette will only start be applied after this number of bounces, so we can get decent sampling in dark areas for example and get a good speedup with less noise.
    - Lower values of this parameter will result in faster (but somewhat noisier) renders.

* yafaray-xml: better autodetection of plugins path, but in some cases "-pp" may still be needed

* Building system: many changes to make the building process easier and more integrated with Git

* Building system: standalone builds generated again

* Building system: added building instructions and test scenes

* QT4 support reintroduced and updated for YafaRay v3, but still in a basic state, many features not available yet for the Qt interface

* Re-added ability to generate Sketchup plugins again

* Texture mapping: allow MirrorX,MirrorY even when Repeat = 1


Bug fixes in v3.2.0:
--------------------
* IMPORTANT: Path/Photon OneDirectLight - attempt to sample lights more uniformly, see: http://www.yafaray.org/node/803
This has been a significant bug, that went unnoticed for a very long time and was causing severe artifacts in Photon Mapping and Path Tracing when lights were not uniformly lighting the scene. Now with this fix, renders should be much more correct and hopefully more realistic!

* IMPORTANT: all integrators, SPPM and path roulette: Fixing non-randomness repetitive patterns, see: http://www.yafaray.org/node/792
Another important bug that went unnoticed for a very long time. A lack of randomness caused severe patterns in BiDirectional integrator and probably some artifacts (in less extent) in the others. We hope this change helps to achieve more correct and realistic results now.

* IMPORTANT: big changes to textures interpolation and colorspace processing, see: http://yafaray.org/node/787
    - I found out that YafaRay was doing the texture interpolation *after* decoding the texels color space. This was causing significant differences in color between standard bilinear/bicubic and when using trilinear or EWA mipmaps.

    - The Core code has been modified so from v3.2.0 onwards all internal image buffers will be converted to "linear RGB" during the texture loading process. That will allow a correct color interpolation process, and probably slightly faster than before. Hopefully this should improve color fidelity respect to the original texture images used for the scene.

    - Also, all textures will be "optimized" by default. I think it's clear by now that optimized textures greatly improve memory usage and apparently don't cause slowdowns (might even make it slightly faster due to reduced RAM access?). To accomodate the extra color information necessary to store "linear RGB" values in the optimized buffers, their size will be around 20-25% bigger respect to v3.1.1, therefore a RAM usage increase will happen now compared with previous versions.

    - For optimal results, from now on the user will be responsible for selecting correct ColorSpaces for all textures, including bump map, normal map, etc. For example for Non-RGB / Stencil / Bump / Normal maps, etc, textures are typically already linear and the user should select "linearRGB" in the texture properties, but if the user (by mistake) keeps the default sRGB for them, YafaRay will (incorrectly) apply the sRGB->LinearRGB conversion causing the values to be incorrect. However, I've added a "fail safe" so for any "float" textures, bump maps, normal maps, etc, when getting colors after interpolatio YafaRay will to a "inverse" color conversion to the original Color Space. This way, even a mistake in user's color space selection in bump maps, normal maps, etc, will not cause any significant problems in the image as they will be converted back to their original color space. However, in this case rendering will be slower and potential artifacts can appear due to interpolation taking place in the wrong color space. For optimal results, the user must select correctly the color space for all textures.
    
* Bidirectional integrator changes:
    - Will be supported again, although will be considered "unstable" until the (many) issues it has are completely fixed.
    - Fixed issue with excessive brightness that happened after render finished.

* Fix for SPPM sudden brightness change when reaching approx 4,300 million photons. See: http://www.yafaray.org/node/772

* Fixed bug that caused many extra render passes to be generated in some cases

* Fixed crash when using Blender Exporter and Core with Ruby bindings support enabled

* Image Texture Interpolation fixes, see: http://www.yafaray.org/node/783

* Angular camera: fixed wrong renders due to incorrect default clipping, see: http://yafaray.org/node/779

* Fixed EXR MultiLayer image file saving

* Fixed uninitialized values generated by Ambient Occlusion sampling

* Several other fixes and improvements, especially for the building system and tools for developers.



YafaRay v3.1.1-beta (2016-09-25)
--------------------------------

Bug fixes in v3.1.1:
--------------------
* IMPORTANT: Fixed Volumetrics regression bug introduced in v3.1.0 (artifacts in the images and crashes). This time it should work fine while also solving the original Volumetric bug that v3.1.0 tried to fix.



YafaRay v3.1.0-beta (2016-09-20)
-------------------------------- 

Feature changes/additions in v3.1.0:
------------------------------------
* New per-material Sampling Factor. New parameter to resample background or not.
These new parameters will *not* work in the first pass, only in the second and subsequent AA passes.

    * Option to resample background, as requested at http://www.yafaray.org/node/214. Works in all integrators except SPPM
    * Option to specify a per-material sampling factor to do additional sampling in certain materials, as requested at http://www.yafaray.org/node/746. Works in all integrators except SPPM

* New WireFrame material properties as well as a WireFrame render pass, as requested in: http://yafaray.org/node/198

  Now, all materials (including Blend material) will have a new Wireframe shading panel. The wireframe can be used in two different ways, depending on whether we want it to be part of the final rendered image or if we want it in a separate Render Pass:
       * Embedded in the Render itself: set a wireframe amount (and optionally map the wireframe amount to a texture). Set the other wireframe options such as color, thickness and softness, and render the scene.
       * Separate Render Pass: make sure the Wireframe amount in the materials is set to 0.0 so the Wireframe does not appear in the Combined Render. Set the rest of the material wireframe options (color, thickness, etc). Enable Render Passes and select Debug-Wireframe pass in one of the passes (preferrably one of the RGBA render passes such as Vector or Color)
      
      Important comments:
       * When using WireFrame, the material may not be fully energy conserving. However, I suppose this is not a problem as the wireframe render is not a photorealistic render in the first place.
       * All Quads and Polygons will be always seen as Triangles (with the crossed line). This is, unfortunately, somthing I cannot solve. YafaRay is currently based on triangle meshes. So, in the Wireframe you will always see triangles, never quads, etc.
       * In the Blend material, the Wireframe shading cannot be mapped to a texture

* New Render Passes: Basic Toon effect, Object Edges and Faces Edges. See: http://www.yafaray.org/community/forum/viewtopic.php?f=23&t=5181
      "Wireframe" material options and render pass will be calculated at "material" integration level. It should be more finely detailed but will only show triangles (quads will show the "crossing" line).

      "Faces edges" will be a render pass calculated at Film level showing the edge contours. In this case, quads will be shown more correctly. However, to calculate the faces edges with the current architecture I had to use indirect methods that are way less precise, so some artifacts and missing or incomplete edges are to be expected, including aliasing in the edges. I've added some parameters that can be accessed in the Render Passes tab for users to fine tune the edges generation as much as possible.

      "Object edges" will be the same, but only rendering object edges and contour, more useful for toon-like renders, for example. Limitations are the same as with the Faces Edges.

      "Toon" render pass: as I already got the above working, I thought it could be nice to work a bit more and get a full "toon-like" Render Pass. This render pass will take the original image, apply some smoothing and color quantization to make the image more "cartoon-like" and add the Object Edge. The users will be able to choose the edge color, adjust a bit the thickness and smoothing/quantization. This will be only a *very basic* toon render pass, don't expect a perfect contouring, etc!! I didn't even try making an animation yet, I suppose there will some edges changing from one frame to the next, not sure if it will be distracting or not...


* Render Badge: ability to select Font ttf file and a font size factor. This will allow better presen
tation and to select fonts with better Unicode support on demand.

New Automatic "absolute/numeric" Object/Material Index render passes, as requested in http://www.yafaray.org/node/745


Bug fixes in v3.1.0:
--------------------
* IMPORTANT: The v3.1.0 Linux builds that can be downloaded in yafaray.org should now be free from the issues "file too short" that happened in the v3.0.2 builds, as described in http://www.yafaray.org/node/759

* IMPORTANT: Fixed (hopefully) the memory allocation bug in Blend materials described at http://www.yafaray.org/
node/763 that caused either crashes or incorrect render results.

* Glass material: more realistic, corrected total reflection including the reflection color/texture. In some scenes this could change the results of Glass rendering!  See http://www.yafaray.org/node/770

* Volumes: fixed issue with white/black areas (negative values, etc) in certain circumstances. See: http://www.yafaray.org/node/766

* Object/Material Absolute Index passes: avoid antialiasing in the edges.
    As requested in http://www.yafaray.org/community/forum/viewtopic.php?f=23&t=5180
    Any "Intermediate" values will be "rounded up" (ceiled). This is one of the many possible criteria to do this, but it gives similar results to Blender Internal, so I will use it.

* Image output denoise: denoise parameters added to the XMLinterface, they didn't work in the XML interface in v3.0.2

* Fixed colorA_t class initialization inconsistencies. We need to keep an eye on this, could cause changes in the Alpha in some scenes (hopefully not)



YafaRay v3.0.2-beta (2016-07-22)
--------------------------------

Changes from v3.0.1-beta to v3.0.2-beta:
----------------------------------------
* ImageFilm load, fix failing load when compiling with GCC v4.8.4.

Changes from v3.0.0-beta to v3.0.1-beta:
----------------------------------------
* Important: Background IBL light sampling fix. This solves a long standing problem with incorrect background lighting accuracy and fireflies. (http://yafaray.org/node/752, http://yafaray.org/node/727, http://yafaray.org/node/566).

* Fix for crash when using yafaray-xml without specifying the type of badge to be used.

* yafaray-xml: new "-ccd" "console-colors-disabled". If specified, disables the Console colors ANSI codes, useful for some 3rd party software that cannot handle ANSI codes well.

* Light photon control: changed back control param names from "shoot_" to "with_" as originally for better backwards compatibility with 3rd party exporters.

* Render Passes: added "generic" external render passes for other Exporters and plugins other than Blender Exporter.

* Render passes: added new debug passes for diagnosing light estimation problems.


Major codebase changes in v3.0.0:
---------------------------------
* Dropped support for Windows XP and MacOSX v10.6. Sorry, but the code changes required this.

* Updated for Blender 2.77a (using Python 3.5).

* Codebase updated from old standard C++98 to the new C++11. This will allow better and easier code maintenance as well as access to newer C++ features to improve YafaRay even more in the future.

* Entire old MultiThreading system replaced by new standard C++11 threads system.

* Windows-MinGW C++11 MultiThreading system using now the library https://github.com/meganz/mingw-std-threads  This should significantly improve render speed in Windows in many scenes by reducing the multithreading overhead.

* Added several Boost libraries to allow saving/loading photon map files and improve unicode/multiplatform compatibility.

* Changes to allow compilation in Visual Studio 2013 (although YafaRay is slower when compiled with VS2013 for some reason).


Feature changes/additions in v3.0.0:
------------------------------------
* Multithreaded Photon Map generation, including multithreaded Photon KDTree building.
This should greatly improve render speeds when using Direct Light+caustic map, Photon Map, SPPM or Path Tracing+photon. 

* Ability to Save/Load/Reuse photon maps.
This should greatly improve render speeds in scenes where only camera moves. See: http://yafaray.org/node/460. WARNING: When loading/reusing Photon Map files, the User is responsible to ensure they match the scene. If the User loads inadequate photon maps, the render results could be totally wrong or even have crashes. USE WITH CARE.

* Ability to AutoSave image files.
Either at the end of each pass or using a user-configurable time interval. This should help if there is a crash or sudden power off, as some images could be obtained from before the incident.

* Ability to AutoSave/Load the main ImageFilm.
This might help to CONTINUE interrupted renders or to add additional samples to a render that has already finished. WARNING: When loading ImageFilm files, the User is responsible to ensure they match the scene. If the ImageFilm does not match the scene and render passes exactly, the render results could be totally wrong or even have crashes. USE WITH CARE.

* Ability to perform Multi-Computer distributed render.
Each computer should have a different Node number [0..1000] to ensure they don't repeat the same samples.

Each computer will generate a different Film. If one of the nodes is set to "Load" the film, it will look for ALL the Film files in the same folder (with the same base file name and frame number) and combine them together to create a combined image with all samples from all individual film files.

* Added OpenCV library and added DeNoise options for the exported image files: JPG, PNG, TGA, TIF.
This feature is not available for HDR/EXR formats. Three parameters are exposed for the users:
  - h(luminance): the higher this is, the more noise reduction you get, but the image can become blurred
  - h(chrominance): the higher, the more color noise reduction, but the colors can become blurred
  - Mix: this is intended to add (on purpose) part of the noise from the original image into the final denoised image. This is to avoid "banding" artifacts in smooth and noiseless surfaces. Setting for example 0.8 means that 80% of the final result will come from the "denoised" image and 20% will come from the original (noisy) image.

* YafaRay-v3 can be installed "in parallel" with other major versions of YafaRay and coexist with them.
"YafaRay v3" will appear as a DIFFERENT renderer and has to be enabled and selected in each scene as if it were a new renderer. This should help to compare the results and features over different major versions as well as allowing using a "stable" and a more "experimental" versions in parallel at the same time. However, support for this is very limited and depends on many factors such as class name clashes, order of registration, dll and library dependency collisions, etc. If having issues, please remove any other yafaray versions and forks and try again. 

* Initial support for filepaths with Unicode characters (accents, etc) can be used now for loading textures, etc. See: http://yafaray.org/node/703    This support is still limited and could fail in some cases.

* Now the user can use CTRL+C in the console to interrupt a render in progress.
This now works in all modes (render into Blender, render to Image files or using yafaray-xml). The interruption due to CTRL+C will now be handled correctly, ensuring the image files and badge are properly saved.

* yafaray-xml: no longer needed to specify the Library path nor the Plugins path.
The old Windows Registry requirement has been removed and it's not necessary anymore. Now, yafaray-xml will load the libraries from the same folder where the yafaray-xml executable resides and it will load the plugins from the subfolder "plugins" respect to the folder where the yafaray-xml executable resides

* Removed option -pst in yafaray-xml, now it has to be enabled via parameter in the xml file

* New Logging system
  - Title, author, comments can be entered now and will appear in the logs and badge.
  - YafaRay compilation information (platform, compiler) and some System Information will appear automatically in the log for easier support of user problems.
  - Console log will show the time of the day, and the duration of the previous event in the log.
  - Render log can be exported to a TXT file automatically, which will include the render results and information.
  - Render log can be exported to an HTML report automaticall, which will include a link to the rendered image and the render results and information.
  - The log verbosity can be selected, to define how much information we want to show in the console or TXT/HTML log (more clear logs when selecting "Info", more details when selecting "Verbose" or "Debug")
  - YafaRay-xml added commandline settings for log file output (txt and/or html) and removed old custom string


* Improved Parameters Badge.
  - New non-intrusive badge, that is appended to the image.
  - Title, author, etc, can be entered in the Exporter to appear in the badge
  - More information, more detailed and clear in the badge. See: http://yafaray.org/node/162 http://yafaray.org/node/224
  - New YafaRay icon for the badge, low contrast grayscale.
  - Custom icon can be selected to replace the YafaRay icon in the badge.
  - Unicode characters can be used now for the badge (accented characters, etc).
  - Badge position can be selected: top or bottom (the icon position changes automatically for nicer presentation)
  - The amount of details shown in the badge can be selected (show render parameters, AA settings, none or both)
  - Show separately render time and photon generation time, plus added total time (including maps generation).
  
* Added new Render Tile "Centre" (now by default) so the renders start in the centre of the image and expand from there. This should allow a faster view of the to-be render, as typically most objects of interest are in the centre of the image.
  
* New Dark areas detection type: curve  (see http://yafaray.org/node/704)

* New more optimized rendering tile structure, to avoid having to wait for the last 1 or 2 tiles to finish rendering before the next pass/frame starts. Now, the last tiles will be automatically subdivided to reduce the waiting times. See: http://yafaray.org/node/709 

* Ability to enable/disable Caustic and/or Diffuse Photons generation in the Photon Map integrator.

* New mirrorX, mirrorY feature for Textures. See: http://yafaray.org/node/227

* More fine-grained Photon Control for light sources. See: http://yafaray.org/node/475

* Ability to set a per-material raytracing depth, for example to speed up scenes with glass. See: http://yafaray.org/node/494

* Parameter to enable/disable World background shadow casting. Option to control separately World background sky/sun shadow casting.

* Bidirectional integrator declared as "Deprecated" and no longer supported, as explained in http://www.yafaray.org/node/720

* Small optimizations for AA resampling, especially when no more pixels are supposed to be resampled

* Add Volumetric rendering to the Blend material.
    When using glass or rough glass in the Blend material, volumetric absorption didn't work. I've added the volumetric rendering to the Blend material so glass/rough glass materials render correctly.
    However, there is a limitation: if blending two materials with different volumetric options, as I cannot "merge" the volumes, I'm using the volume from the first material for blend amount values [0.0-0.5] and the volume from the second material for blend amount ]0.5-1.0]. This is totally not ideal, but better than before in my opinion.

* Added SmartIBL functionality to reduce noise when using World HDRI textures for lighting. The functionality adds a new parameter "SmartIBL blur" that blurs the World texture used for lighting without affecting the world texture used for reflections, etc. High values can cause slowdowns at render process start. This was requested at http://www.yafaray.org/node/566 and http://www.yafaray.org/node/727

* Added IBL sampling clamp to reduce noise when using World HDRI textures for lighting. In some cases blur is not good enough to remove noise and it causes blurred shadows. IBL clamping would help sometimes to reduce noise so blur is not needed, but it could lead to inexact overall lighting, etc. This was requested at http://www.yafaray.org/node/566 and http://www.yafaray.org/node/727

* Added Texture Color Controls to be able to control the texture brigthness, contrast, saturation, hue, etc, as requested at http://www.yafaray.org/node/334

* Added Texture Color Ramps, to be able to create much more interesting procedural textures, also requested at http://www.yafaray.org/node/334

* Implemented all remaining progressions in the Blend texture (only linear was implemented), requested at http://www.yafaray.org/node/313


Bug fixes in v3.0.0:
--------------------
* Fixed: Soft Spotlight too dark when nearer than 1.0 unit from objects. See: http://yafaray.org/node/587

* Fixed: Rough Glass not working in Blend materials. See: http://yafaray.org/node/365

* Fixed: black spots in some cases. See: http://yafaray.org/node/730

* Fix AO Clay pass self shadow problem, reported by RioFranco (Olivier)

* Changes in SWIG code to try to reduce crashes. Not sure if this will solve all problems but I hope this change helps.

* Bidirectional: fix crash when using sky background as only light source

* SPPM progress bar and tags fixed



YafaRay v2.1.1 (2016-04-16)
---------------------------
No changes respect to Experimental v2.1.1, only version changes (removed "Experimental")



YafaRay-E (experimental) v2.1.1 (2016-02-06)
--------------------------------------------
Note: there has been important changes and bug fixes in this version. They have solved some long-standing issues but perhaps they could cause new issues and unexpected results, so we have to keep an eye on them.

* IMPORTANT: Fix for incorrect IBL lighting in World Background Texture when set to Angular. See: http://www.yafaray.org/node/714

* IMPORTANT: Adjustment to the automatic intersection/shadow bias calculation formula to avoid black artifacts in the scenes with fine details. However, now we can get again some black dots in some scenes again. For now, no good solution at hand (any good solution would require fundamental changes to the engine and probably slow down the renders in a significant amount). However, I hope to have found a better balance now. See: http://blenderartists.org/forum/showthread.php?389385-YafaRay-E-(Experimental)-v2-0-2-builds-Windows-Linux-and-Mac-OSX-for-Blender-2-76b&p=3004974&viewfull=1#post3004974

* IMPORTANT: Fix for black dots (alpha=0) sometimes when using Mitchell/Lanzcos filters. It's not clear what is the best way of solving this problem. This fix is the one that makes more sense but could cause new issues, we have to keep an eye on this. See: http://www.yafaray.org/node/712

* Fixed Black artifacts in World Background Textures. See: http://www.yafaray.org/node/714

* Fixed crash when using textures with Normal or Window coordinates (which are view dependent) along with Caustic Photons. However, we have to consider that Photons are supposed to be view-independent, but when using textures with Window or Normal coordinates (which are view dependant), then the Photons WILL also be view dependant as well! So, using textures with "tricks" like Normal or Windows coordinates can cause low frequency noise in animations with Photons. This would not be a problem, but the price for using such "tricks" in renders.

* Fixed: console colors including blue component were incorect for Windows builds



YafaRay-E (experimental) v2.1.0 (2016-01-31)
--------------------------------------------

- Added Normal Coordinates for textures, so you can use a gradient texture mapped to normal coordinates to simulate, for example, some cloth materials (see http://yafaray.org/node/188 )
- Fixed some crashes when changing Material/Texture settings



YafaRay-E (experimental) v2.0.2 (2016-01-26)
--------------------------------------------
- Fix for Oren Nayar to avoid generating white/black dots when used together with bump mapping
- Fix for black dots using HDRI spherical and Coated Glossy



YafaRay-E (experimental) v2.0.1 (2016-01-05)
--------------------------------------------
- Fixed Instances not working in v2.0.0 (regression)



YafaRay-E (experimental) v2.0.0 (2016-01-01)
--------------------------------------------
- STRUCTURAL CHANGES to implement Render Passes. The Passes are especially intended for Direct Light and Photon Mapping integrators. Some passes may not work (or work incorrectly) in other integrators.
- STRUCTURAL CHANGES to implement Render Views (Stereo3D / MultiView)
- STRUCTURAL CHANGES to implement a (hopefully) improved more automatic and reliable Shadow Bias and Intersection Bias, based on triangle size and coordinates positions.
- New Noise Control parameters, including a new clamping function to reduce noise at the cost of reducing physical accuracy and realism.
- RAM optimization options for JPG,PNG,TGA and TIFF textures. Using "optimized" (by default now) will reduce RAM usage for those textures in approx. 70%. The "optimized" option is lossless (except in TIFF 16bit). There is a "compressed" option that is lossy but allows an extra reduction of approx. 20% in RAM usage.
- Support for exporting in MultiLayer EXR files.
- XML rendering now supports an option to save partially rendered images every "x" seconds, probably useful when creaiting external GUIs to the XML interface.
- Ability to select what "internal" YafaRay Render Pass has to be mapped to an "external" Render Pass. This provides a lot of power and flexibility when generating Render Passes.
- Object ID/Material ID passes, with option of automatic ID color pass.
- Object ID Masking and Material ID masking (objects only, objects+shadows, shadows only)
- Debug passes and UV debug pass available to be able to find mesh/mapping/texturing problems at the same time as rendering the scene.
- Samplerate pass, to apply post-processing filters to the noisier parts of the render.
- Added dispersive caustics to SPPM.
- Changes to dispersion in rough glass.
- Removal of entire Qt interface. As far as we know it was old, unmaintained and probably useless anyway.
- Fix (although horrible) for the Bidirectional integrator generating black renders with some types of lights.
- A few speed improvements, I don't expect a significant change but I hope they help a bit, especially in 64bit systems.



YafaRay-E (experimental) v1.1.0 (2015-11-06)
--------------------------------------------
- Changes to the Core code and build files to enable building for Mac OSX 64bit (v10.6 or higher), based on the excellent work from Jens Verwiebe. Thank you very much, Jens!!

- Added a new "Resampled Floor" parameter to the Adaptative AA calculations, to increase the noise reduction performance. The idea is that if the amount of resampled pixels go below that "floor" value during a certain pass, the AA threshold is automatically decreased in 10% for the next pass. More information: http://yafaray.org/node/690

- Added a per-material parameter to control reception of shadows. Now it's possible to select if a material should receive shadows from other objects (as default) or not. See: http://yafaray.org/node/687

- Minor changes for existing material visibility feature to improve (just a tiny bit) performance.



YafaRay-E (experimental) v1.0.0 (2015-10-13)
--------------------------------------------
Note: from v1.0.0 I will no longer use the suffix "beta", as all YafaRay-Experimental versions are inherently betas ;-). I will use for version scheme: "Major.Minor.Bugfix". Major will be very important and structural changes with possible API breakage, Minor will be new and modified functionality without API breakage, Bugfix will be small changes and bugfixes.

- IMPORTANT CHANGES to Color Management and Color Pipeline Linear Workflow: http://www.yafaray.org/node/670
Initial prototype to try to fix the (apparently broken) YafaRay color pipeline workflow and to replace the simple gamma input/output correction with a proper sRGB decoding/coding in non-HDR files.

More information here: http://www.yafaray.org/node/670

So, I've prepared a YafaRay prototype that fixes the next issues:

* Improved Blender Color Space integration.
* The "simple" gamma correction has been replaced by Color Spaces:
	- LinearRGB			Linear values, no gamma correction
	- sRGB				sRGB encoding/decoding
	- XYZ				XYZ (very experimental) support
	- Raw_Manual_Gamma	Raw linear values that allow to set a simple gamma output correction manually

* Gamma input correction no longer used. The color picker floating point color values will be considered already linear and no conversion applied to them.
* For textures, added specific per-texture Color Space and gamma parameters.
* In yafaray-xml, new commandline option added: "-ics" or "--input-color-space" that allows to select how to interpret the XML color values. By default, for backwards compatibility, color values will be read as "LinearRGB", but using "-ics sRGB", the color values will be interpreted as sRGB. This setting does *not* affect the textures, as they have already per-texture specific color space/gamma parameters.


Several bug tracker entries are supposed to be fixed with this change:
* Color pipeline bug: http://www.yafaray.org/node/670
* Linear output forced on every scene: http://www.yafaray.org/node/603
* Gamma 1.80 input on linux: http://www.yafaray.org/node/604
* Forward compatibility with Blender Color Management: http://www.yafaray.org/node/547
* Gamma correction performed on EXR files: http://www.yafaray.org/node/549



- IMPORTANT CHANGES to Volumetrics for proper raytracing of volumes.
Problems with volumes and transparent objects have been reported in the bug tracker several times:
http://yafaray.org/node/289
http://yafaray.org/node/666

The problem was that Volumes were not really included in the raytracing process, so they were not reflected nor refracted. Now Volumes have been included in the raytracing process, so they can be refracted and reflected as any other objects. This is a significant change that could cause new issues, so please let us know about any problems in YafaRay bug tracker.

Now, if there are no parameters set in the XML for transparent background or transparent refracted background, their default values will be "false" and not "true" as until now. This will avoid confusion due to the new way "transparent refracted background" works, not rendering the background at all so volumes rendered against a transparent background do not carry "remains" of the background with them. 

- Fix for attenuation when using 2 or more volumetric objects: http://www.yafaray.org/node/332

- Fix for error message "Index out of bounds in pdf1D_t" when spotlights with falloff > 0.70 and photons were used: http://www.yafaray.org/node/681



YafaRay-E (experimental) v0.1.99-beta4c (2015-07-29)
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Note: builds were not created for this version, as it was only used for limited-scale testing. However, the changes made in this version remain in newer Releases and builds.

More info about the discussion and changes: http://www.yafaray.org/node/662

- Fix for issue where Final Gather uses non-IBL background in glass: http://www.yafaray.org/node/572

- Fix for white dots in Path Tracer integrator: http://www.yafaray.org/node/662

- Fix for bump mapping artifacts: http://www.yafaray.org/node/660
WARNING: I've made significant changes to the bump mapping when using image textures, trying to improve it and get results more similar to Blender, but it could cause new issues so enough testing should be done to make sure bump/normal mapping still works correctly.
 
- Improvements to the noise fireflies in Rough Glass: http://www.yafaray.org/node/663

- New parameter to enable/disable lights.
In the XML, into each "light" section you can add:
<light_enabled bval="false"/> or <light_enabled bval="true"/>

- Ability to control per-light shadow casting.
In the xml file, you can add this to the "light" sections:
<cast_shadows bval="true"/> or <cast_shadows bval="false"/>

- New per-material "visibility" enum parameter that can have the following values.

'normal' (default): Normal - Normal visibility - visible casting shadows.
'no_shadows': No shadows - visible but not casting shadows.
'shadow_only': Shadows only - invisible but casting shadows.
'invisible': Invisible: totally invisible material.

This new parameter is at the bottom of the material panel, in the new advanced settings. In XML it would be something like, in the material section, for example:

<visibility sval="shadow_only"/>



YafaRay-E (experimental) v0.1.99-beta4 (2015-06-20)
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- New advanced parameters for fine control of Shadow Bias/Min Ray Dist if the automatic calculation is not good enough. Please give us feedback about it in the forum: http://www.yafaray.org/community/forum/viewtopic.php?f=23&t=5084

- Fix for caustics noise coming from Non-IBL background in Photon Mapping. Now the background will only be used for Caustics if IBL is enabled and (if there is a caustics parameter available in the background settings) if caustics is enabled in the background.



YafaRay-E (experimental) v0.1.99-beta3 (2015-05-02)
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- Fix for -NAN results in the Bidirectional integrator when using Architectural, Angular and Ortho cameras. See: http://www.yafaray.org/node/538

- Fix for problem with Rough Glass too bright when dispersion is enabled. See: http://www.yafaray.org/node/642

- Extended Texture Mapping system, allowing using textures to map additional properties in materials, to be able to create either more realistic or more exotic materials and reduce the dependency on the "blend" material. More information in: http://www.yafaray.org/community/forum/viewtopic.php?f=22&t=5091

Important note: when using some of the new mappings, the renders may slow down. I'm not sure whether it's because of the additional calculations (very likely) or if it's something we can optimize further in the future. In any case, it should only be noticeable when using the new mappings, and I think it's worth the ability to create new materials now.

The new texture mappings in addition to the existing ones are: 
	- Diffuse Reflection Amount in Shiny Diffuse, Glossy and Coated Glossy materials
	- Sigma factor for Oren Nayar in Shiny Diffuse, Glossy and Coated Glossy materials
	- Filter color in Glass and Rough Glass.
	- IOR refractive factor in Glass and Rough Glass. The texture amounts are added to the IOR of the material.
	- IOR refractive factor for the Fresnel in Shiny Diffuse and Coated Glossy materials.
	- Roughness factor in Rough Glass material.
	- Exponent factor in Glossy and Coated Glossy materials
	- Mirror amount in Coated Glossy materials.
	- Mirror Color in Coated Glossy Materials



YafaRay-E (experimental) v0.1.99-beta2 (2015-04-18)
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- Fix for bad NaN normals that happened sometimes.
- Calculate automatically Shadow Bias and Minimum Ray Dist depending on the scene size. This is to avoid black artifacts when resizing the objects. However as it's a fundamental change that affects everything, perhaps some new artifacts could appear in the images now and further fine tuning needed in this new formula. Please give us feedback about it in the forum:
http://www.yafaray.org/community/forum/viewtopic.php?f=23&t=5084 



YafaRay-E (experimental) v0.1.99-beta1 (2015-04-11)
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Based on the official stable YafaRay v0.1.5 git version

- Texture mapping of Sigma factor in Shiny Diffuse/Oren Nayar.
- Fix for Negated colors in Musgrave/Voronoi textures mapped to diffuse color.