This pull request adds a new tipe of resource handles (thin handles).
These are intended for cases where a resource buffer with more than one
entry for each object is needed (for example, one entry per material
slot).
While it's already possible to have multiple regular handles for the
same object, they have a non-trivial overhead in terms of uploaded
data (matrix, bounds, object info) and computation (visibility
culling).
Thin handles store an indirection buffer pointing to their "parent"
regular handle, therefore multiple thin handles can share the same
per-object data and visibility culling computation.
Thin handles can only be used in their own Pass type (PassMainThin),
so passes that don't need them don't have to pay the overhead.
This pull request also includes the update of the Workbench Next
pre-pass to use PassMainThin, which is the main reason for the
implementation of this feature.
The main change from the previous PR is that the thin handles are now
stored directly in the main resource_id_buf, to avoid wasting an extra
bind slot.
Pull Request #105261
This is a new implementation of the draw manager using modern
rendering practices and GPU driven culling.
This only ports features that are not considered deprecated or to be
removed.
The old DRW API is kept working along side this new one, and does not
interfeer with it. However this needed some more hacking inside the
draw_view_lib.glsl. At least the create info are well separated.
The reviewer might start by looking at `draw_pass_test.cc` to see the
API in usage.
Important files are `draw_pass.hh`, `draw_command.hh`,
`draw_command_shared.hh`.
In a nutshell (for a developper used to old DRW API):
- `DRWShadingGroups` are replaced by `Pass<T>::Sub`.
- Contrary to DRWShadingGroups, all commands recorded inside a pass or
sub-pass (even binds / push_constant / uniforms) will be executed in order.
- All memory is managed per object (except for Sub-Pass which are managed
by their parent pass) and not from draw manager pools. So passes "can"
potentially be recorded once and submitted multiple time (but this is
not really encouraged for now). The only implicit link is between resource
lifetime and `ResourceHandles`
- Sub passes can be any level deep.
- IMPORTANT: All state propagate from sub pass to subpass. There is no
state stack concept anymore. Ensure the correct render state is set before
drawing anything using `Pass::state_set()`.
- The drawcalls now needs a `ResourceHandle` instead of an `Object *`.
This is to remove any implicit dependency between `Pass` and `Manager`.
This was a huge problem in old implementation since the manager did not
know what to pull from the object. Now it is explicitly requested by the
engine.
- The pases need to be submitted to a `draw::Manager` instance which can
be retrieved using `DRW_manager_get()` (for now).
Internally:
- All object data are stored in contiguous storage buffers. Removing a lot
of complexity in the pass submission.
- Draw calls are sorted and visibility tested on GPU. Making more modern
culling and better instancing usage possible in the future.
- Unit Tests have been added for regression testing and avoid most API
breakage.
- `draw::View` now contains culling data for all objects in the scene
allowing caching for multiple views.
- Bounding box and sphere final setup is moved to GPU.
- Some global resources locations have been hardcoded to reduce complexity.
What is missing:
- ~~Workaround for lack of gl_BaseInstanceARB.~~ Done
- ~~Object Uniform Attributes.~~ Done (Not in this patch)
- Workaround for hardware supporting a maximum of 8 SSBO.
Reviewed By: jbakker
Differential Revision: https://developer.blender.org/D15817