Change Details

NOTE: Is an early access version. It is re-implemented in a way which does differential rendering: the path is split at a first non-transparent bounce when shadow catcher object is hit. One path will track state of the shadow catcher object without other objects affecting it. The other path is rendering scene as usual. Upon user access of the shadow catcher pass the result is calculated as combined pass divided by the pass with shadow catcher object. This gives a pass which is to be multiplied with a backdrop to transport light and shadows caught. For the artificial objects which are to be added to the backdrop there is a matte pass. This pass is to be alpha-over onto the backdrop (after multiplication). This process is a bit more involved that the old single pass approach, but it allows to deal with indirect light, caustics. It is possible to get some approximation of shadows for the matte pass to have a simple workflow. It is a possibility, which is not done yet. In fact, would actually be better to only do it if absolutely needed. Example file using Fabrik footage: {F10055171} The footage is available at T86591#1131707 and soon will be put to a more visible/permanent place. Example result: {F10055172} The example file is a quick developer-working-on-laptop version, so the reconstructed mesh is not very well aligned, and the light is only to visualize possibilities of the new shadow catcher. TODO: - More permanent link to the Fabrik footage, so that we can reference it from everywhere. - Support shadow catcher which is behind transparent object. - Support GPU. - Better naming for what is called "split state". Maybe be explicit and refer to it as "shadow catcher state". Not sure if we will have state split for other functionality (aka, does it worth trying to be too generic here?) - Make the state copy more reusable (for compactification). The current state of the code is probably 95% there: need to somehow define state into which we do copy (and not assume we always copy to the split state). - Look into old-style approximation for a single alpha-over behavior.

It is re-implemented in a way which does differential rendering: the path is split at a first non-transparent bounce when shadow catcher object is hit. One path will track state of the shadow catcher object without other objects affecting it. The other path is rendering scene as usual. Upon user access of the shadow catcher pass the result is calculated as combined pass divided by the pass with shadow catcher object. This gives a pass which is to be multiplied with a backdrop to transport light and shadows caught. For the artificial objects which are to be added to the backdrop there is an internal matte pass. This pass is presented as combined to artists, so they alpha-over it onto the footage as usual. In the future we might implement shadow approximation to gain old-style shadow catcher behavior (maybe for compatibility reasons, maybe for some artistic reasons). This process is a bit more involved that the old single pass approach, but it allows to deal with indirect light, caustics. Example file: {F10059890} Example result: {F10055172} The footage is the Old_Factory MVI_4005.mov from https://cloud.blender.org/training/track-match-blend/56040f9b044a2a00ad6c660d

NOTE: Is an early access version. It is re-implemented in a way which does differential rendering: the path is split at a first non-transparent bounce when shadow catcher object is hit. One path will track state of the shadow catcher object without other objects affecting it. The other path is rendering scene as usual. Upon user access of the shadow catcher pass the result is calculated as combined pass divided by the pass with shadow catcher object. This gives a pass which is to be multiplied with a backdrop to transport light and shadows caught. For the artificial objects which are to be added to the backdrop there is athere is an internal matte pass. This pass is to be alpha-over onto the backdrop (afterpresented as combined multiplication). This process is a bit more involved thatto artists, so they alpha-over it onto the old single pass approach,footage as usual. In the but it allows to deal with indirect light, caustics. It is possible to get somefuture we might implement shadow approximation of shadows for the matte passto gain old-style to have a simple workflow. It is a possshadow catcher behavior (maybe for compatibility reasons, which is not done yet.maybe for In fact, would actually be better to only do it if absolutely neededsome artistic reasons). Example file using Fabrik footage: {F10055171} The footage is available at T86591#1131707 and soon will be put to aThis process is a bit more involved that the old single pass approach, more visible/permanent placebut it allows to deal with indirect light, caustics. Example file: {F10059890} Example result: {F10055172} The example file is a quick developer-working-on-laptop version, so the reconstructed mesh is not very well aligned, and the light is only to visualize possibilities of the new shadow catcher.footage is the Old_Factory MVI_4005.mov from TODO: - More permanent link to the Fabrik footage, so that we can reference it from everywhere. - Support shadow catcher which is behind transparent object. - Support GPU. - Better naming for what is called "split state". Maybe be explicit and refer to it as "shadow catcher state". Not sure if we will have state split for other functionality (aka, does it worth trying to be too generic here?) - Make the state copy more reusable (for compactification). The current state of the code is probably 95% there: need to somehow define state into which we do copy (and not assume we always copy to the split state). - Look into old-style approximation for a single alpha-over behavior.https://cloud.blender.org/training/track-match-blend/56040f9b044a2a00ad6c660d