# Dynamic declarations for some compositor nodes.

## Goals:
Stop using operators to change sockets directly. Delegate this to the node declaration system. This provides most of the other benefits:
1. Management of topology updates, drawing.
2. Handling old data and socket references from declaration code.
3. Using a newer API.

## Way to do that:
1. For `CMP_NODE_OUTPUT_FILE` node:
1.1. Added in node.storage stucture linked list to contain metadata of each output socket.
1.2. Added `declare_dynamic` function for generate sockets based on metadata. See `blender::nodes::node_group_declare_dynamic` as example implementation.
1.3. Change node property operators to change only metadata.
2. All `bNodeSocketTemplate` replace by static declarations. See [ed9b21098dd27bf9364397357f89b4c2648f40c2](https://projects.blender.org/blender/blender/commit/ed9b21098dd27bf9364397357f89b4c2648f40c2) as example.

It is best to do this separately for each node in an individual PR.
Nodes to change:
1. `CMP_NODE_OUTPUT_FILE`.
2. `CMP_NODE_R_LAYERS.
3. `CMP_NODE_CRYPTOMATTE_LEGACY` ?
4. `CMP_NODE_SWITCH_VIEW`.