Material::compile() can be used to asynchronously ask the backend to
compile a subset of the variants of a Material and be notified when
done. This can be used during initialization to avoid hiccups later.
This will also force caching of those material programs if the
Platform provides the blob cache API.
This doesn't add or remove functionality, but merely changes the API
to create an Engine, to be more consistant with how we construct other
objects in filament.
You can now use Engine::Builder to construct an Engine.
By default ancillary buffers are discarded on commit (eg. depth buffer),
but in certain situations the platform may want to preserve them. this
new virtual allows a concrete implementation to specify which buffers
need to be preserved.
Note that in ES2 mode, the depth value returned by the picking API
only has 8-bits precision and incurs a bigger performance penalty,
because glReadPixels is synchronous.
This is only the first step where we:
- clean-up some code to prepare for 2nd step
- add support for the linear->srgb in the shaders
The linear->srgb conversion is protected by a
specification constant and will be enabled only
if the corresponding EGL extension in not present.
Then, if enabled, the actual conversion is
controlled by a uniform so that it can be
selectively enabled on swapchains that have it
turned on.
In this change, the emulation logic that sets
these gates is not implemented (that's step 2).
This CL contains two parts:
- changes to matc/filamat
- changes to filament itself
Filamat can now generate ES2 compatible shaders. Only the unlit variant
is supported. Fog and picking are supported as well.
post-processing, skinning, instancing, all lighting and shadowing are not supported.
Filament is updated to not issue commands that are not supported in ES2.
Addtionnally, the hello-triangle sample is updated to work on an ES2 device.
From the backend's point of view, UBOs are emulated with uniforms.
The backend will maintain a data structure that maps an offset into
the UBO to a uniform and will do the appropriate glUniform* calls
at the right time and if needed (e.g. only if the UBO content has
changed).
The mapping from an UBO content to uniforms is passed to Program
upon creation.
This first round is mostly about making the backend compile with the
ES2 header only and use the ES2 code path when running on an ES2
context. We also add feature level 0, which corresponds to ES2
devices.
We introduce the macro FILAMENT_SILENCE_NOT_SUPPORTED_BY_ES2, which is
exclusively used to compile-out code that cannot compile with ES2
headers. This macro is active when ES2 headers are used.
There is also a new `OpenGLContext::isES2()` method that is returns
whether we're running an ES2 context, either statically (desktop, ios)
or dynamically (mobile).
This PR should add or remove any functionality.
