Change Details

This patch allows animation of the collection visibility buttons. Basically completes the work started by @aligorith in {rBd1e3ba22a03c}. In that commit "all necessary data and animation editor support changes" were implemented. But the depsgraph support was incomplete. So, in this patch, I only focused on the changes in the depsgraph (and I trusted the original work). ##Problematic: In the master, a few things get in the way of implementing animation for collections. These things are: **1. Deg nodes and relations are not created for invisible collections.** Every time a collection flag is changed in rna, depsgraph relations are recreated which "remove" nodes from hidden collections. Since an invisible collection has no deg nodes, the operand that updates them is never called. So if the visibility of a collection is animated in this case, nothing will change. **2. The function that updates any changes to a Collection is not thread-safe and adds a lot of overhead.** When a collection flag is changed in rna, the `BKE_main_collection_sync(bmain)` function is called. This function deletes lists, Ghash, arrays from all Blender ViewLayers and Collections and recreates them no matter if an object was deleted or if a Base flag was just changed. It is also not thread-safe, which makes the call unsuitable for an operand of a depsgraph node. ##Solution: The solution is similar to what is seen for object visibility animation (with some changes). **1. Deg nodes and relations to Collections are always created if the collection is animated.** This solves the issue of operands not being called if the collection is invisible. There are different ways to solve this problem (like calling `DEG_relations_tag_update` in the callback to set the rna value instead of the update), but I preferred to follow what is seen for Objects, that is, always create the relations. Unlike Objects, relations are only created if the datablock is animated. **2. Implement an update function that updates only the Base flags of a ViewLayer.** The lightweight `BKE_layer_collection_sync_base_flags` function was implemented to be called in the operand. This avoids having to call `BKE_main_collection_sync`.

This patch allows animation of the collection visibility buttons (those eyes in the outliner). Basically concludes the work initiated by @aligorith on {rBd1e3ba22a03c}. In that commit (rBd1e3ba22a03c) all necessary data for support to animation of the ID were implemented. But the depsgraph support was incomplete. So this patch only focused on the depsgraph changes (and trusted the original work). ##Problematic (what hinders the implementation in the depsgraph area): **1. Deg nodes and relations are not created for invisible collections.** Every time a collection flag is changed in rna, depsgraph relations are recreated which "remove" nodes from hidden collections. This means that if animation tries to unhide a collection, there are no nodes to update the scene. **2. The function that updates a Collection is not thread-safe and adds a lot of overhead.** As it is not thread-safe, the function is unsuitable as an operand for the depsgraph node. Also it adds a lot of overhead. Then a collection flag is changed in rna, the `BKE_main_collection_sync(bmain)` function is called. This function deletes lists, Ghash, arrays from all Blender ViewLayers and Collections and recreates them no matter if an object was deleted or if a Base flag was just changed. ##Proposed Solution: The solution is similar to what is seen for object visibility animation (with some changes). **1. Deg nodes and relations to Collections are always created if the collection is animated.** Like Objects, relations are only created if the datablock is animated. This solves the issue of operands not being called if the collection is hidden. **2. Implement an update function that updates only the Base flags of a ViewLayer.** The lightweight `BKE_layer_collection_sync_base_flags` function was implemented to be called in the operand. This avoids having to call `BKE_main_collection_sync`. ##To Do The `BKE_layer_collection_sync_base_flags` function, while working fine in its current state, does not follow the depsgraph convention as it directly reads bmain which may not be thread-safe

This patch allows animation of the collection visibility buttons (those eyes in the outliner). Basically completncludes the work starinitiated by @aligorith in on {rBd1e3ba22a03c}. In that commit "all necessary data and animation edit(rBd1e3ba22a03c) all necessary data for support changes"to were implemented. Butanimation of the depsgraph support was incoID were implete. So, in this patch,mented. I only focused onBut the changes in the depsgraphdepsgraph support was (and I trusted the original work)incomplete. ##Problematic:So this patch only focused on the depsgraph changes (and trusted the In the master, a few things get in the way oforiginal work). ##Problematic (what hinders the implementing animation for collections. These things in the depsgraph are:a): **1. Deg nodes and relations are not created for invisible collections.** Every time a collection flag is changed in rna, depsgraph relations are recreated which "remove" nodes from hidden collections. Since an invisible collection has no deg nodes, the operand that updatesThis means that them is never called.if animation tries to unhide a collection, So if the visibility of a collection is animatedthere are no nodes to update in this case, nothing will changethe scene. **2. The function that updates any changes to a Collection is not thread-safe and adds a lot of overhead.** When a collection flag is changed in rnaAs it is not thread-safe, the function is unsuitable as an operand for the depsgraph node. Also it adds a lot of overhead. Then a collection flag is changed in rna, the `BKE_main_collection_sync(bmain)` function is called. This function deletes lists, Ghash, arrays from all Blender ViewLayers and Collections and recreates them no matter if an object was deleted or if a Base flag was just changed. It is also not thread-safe, which makes the call unsuitable for an operand of a depsgraph node. ####Proposed Solution: The solution is similar to what is seen for object visibility animation (with some changes). **1. Deg nodes and relations to Collections are always created if the collection is animated.** This solves the issue of operands not being called if the collection is invisible. There are different ways to solve this problem (like callingLike Objects, relations are only created if the datablock is animated. `DEG_relations_tag_update` in the callback to set the rna value instead of the update), but I preferred to follow what is seen for Objects,This solves the issue of operands not being called if the collection is that is, always create the relations. Unlike Objects, relations are only created if the datablock is animatedhidden. **2. Implement an update function that updates only the Base flags of a ViewLayer.** The lightweight `BKE_layer_collection_sync_base_flags` function was implemented to be called in the operand. This avoids having to call `BKE_main_collection_sync`. ##To Do The `BKE_layer_collection_sync_base_flags` function, while working fine in its current state, does not follow the depsgraph convention as it directly reads bmain which may not be thread-safe