Previously the backend private state was used to either link to an
authority material or provide authoritative program state. The mechanism
seemed overly complex and felt very fragile. I made a recent comment
which added a lot of documentation to make it easier to understand but
still it didn't feel very elegant.
This patch takes a slightly different approach; we now have a
ref-counted ArbfpProgramState object which encapsulates a single ARBfp
program and the backend private state now just has a single member which
is a pointer to one of these arbfp_program_state objects. We no longer
need to cache pointers to our arbfp-authority and so we can get rid of
a lot of awkward code that ensured these pointers were
updated/invalidated at the right times. The program state objects are
not tightly bound to a material so it will also allow us to later
implement a cache mechanism that lets us share state outside a materials
ancestry. This may help to optimize code not following the
recommendations of deriving materials from templates, avoiding one-shot
materials and not repeatedly modifying materials because even if a
material's ancestry doesn't naturally lead us to shareable state we can
fallback to searching for shareable state using central hash tables.
This adds a way to iterate the layer indices of the given material since
cogl_material_get_layers has been deprecated. The user provides a
callback to be called once for each layer.
Because modification of layers in the callback may potentially
invalidate any number of the internal CoglMaterialLayer structures and
invalidate the material's layer cache this should be more robust than
cogl_material_get_layers() which used to return a const GList *
pointing directly to internal state.
This fixes the material backends to declare their constant vtable in the
c file with a corresponding extern declaration in the header. This
should fix complaints about duplicate symbols seen on OSX.
Instead of lazily incorporating combine constants as arbfp PARAM
constants in the source directly we now use program.local parameters
instead so we can avoid repeating codegen if a material's combine
constant is updated. This should be a big win for applications animating
a constant used for example in an animated interpolation, such as
gnome-shell.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2280
This makes it so we don't consider LAYER_STATE_TEXTURE changes to affect
the arbfp code. This should avoid a lot of unneeded passes of
code generation for applications modifying the texture for a layer.
This makes it so we only notify backends of either a single material
change or a single layer change. Previously all material STATE_LAYERS
changes would be followed by a more detailed layer change.
For backends that perform code generation for fragment processing they
typically need to understand the details of how layers get changed to
determine if they need to repeat codegen. It doesn't help them to report
a material STATE_LAYERS change for all layer changes since it's so
broad, they really need to wait for the layer change to be notified.
What does help though is to report a STATE_LAYERS change for a change in
material->n_layers because they typically do need to repeat codegen in
that case.
This fixes a number of issues relating to how we track the arbfp private
state associated with CoglMaterials. At the same time it adds much more
extensive code documentation to try and make it a bit more approachable.
When notifying a backend about a layer being modified we now pass the
layers current owner for reference. NB: Although a layer can indirectly
be referenced by multiple layers, a layer is considered immutable once
it has dependants, so there is only ever one material associated with a
layer being modified. Passing the material pointer to the backends
layer_pre_change callback can be useful for backends that associate
their private state with materials and may need to update that state in
response to layer changes.
This renames the get_arbfp_authority function to
get_arbfp_authority_no_check to clarify that the function doesn't
validate that the authority cache is still valid by looking at the age
of the referenced material. The function should only be used when we
*know* the cache has already been checked.
We are going to start tracking more per-texture unit state with arbfp
private state so this adds an internal UnitState type and we allocate an
array of these when setting up a new private state structure. The first
thing that has been moved into this is the sampled boolean to know when
a particular texture unit gets sampled from in the generated arbfp code.
This makes CoglProgram/Shader automatically detect when the user has
given an ARBfp program by checking for "!!ARBfp1.0" at the beginning of
the user's source.
ARBfp local parameters can be set with cogl_program_uniform_float
assuming you pass a @size of 4 (all ARBfp program.local parameters
are vectors of 4 floats).
This doesn't expose ARBfp environment parameters or double precision
local parameters.
g_ascii_dtostr was being used in four separate arguments to
g_string_append_printf but all invocations of it were using the same
buffer. This would end up with all of the arguments having the same
value which would depend on whichever order the compiler evaluates
them in. This patches changes it to use a multi-dimensional array and
a loop to fill in the separate buffers.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2219
The ARBfp programs are created with a printf() wrapper, which usually
fails in non-en locales as soon as you start throwing things like
floating point values in the mix.
We should use the g_ascii_dtostr() function which places a double into a
string buffer in a locale-independent way.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2219
This adds a publicly exposed experimental API for a 3D texture
backend. There is a feature flag which can be checked for whether 3D
textures are supported. Although we require OpenGL 1.2 which has 3D
textures in core, GLES only provides them through an extension so the
feature can be used to detect that.
The textures can be created with one of two new API functions :-
cogl_texture_3d_new_with_size
and
cogl_texture_3d_new_from_data
There is also internally a new_from_bitmap function. new_from_data is
implemented in terms of this function.
The two constructors are effectively the only way to upload data to a
3D texture. It does not work to call glTexImage2D with the
GL_TEXTURE_3D target so the virtual for cogl_texture_set_region does
nothing. It would be possible to make cogl_texture_get_data do
something sensible like returning all of the images as a single long
image but this is not currently implemented and instead the virtual
just always fails. We may want to add API specific to the 3D texture
backend to get and set a sub region of the texture.
All of those three functions can throw a GError. This will happen if
the GPU does not support 3D textures or it does not support NPOTs and
an NPOT size is requested. It will also fail if the FBO extension is
not supported and the COGL_TEXTURE_NO_AUTO_MIPMAP flag is not
given. This could be avoided by copying the code for the
GL_GENERATE_MIPMAP TexParameter fallback, but in the interests of
keeping the code simple this is not yet done.
This adds a couple of functions to cogl-texture-driver for uploading
3D data and querying the 3D proxy
texture. prep_gl_for_pixels_upload_full now also takes sets the
GL_UNPACK_IMAGE_HEIGHT parameter so that 3D textures can have padding
between the images. Whenever 3D texture is uploading, both the height
of the images and the height of all of the data is specified (either
explicitly or implicilty from the CoglBitmap) so that the image height
can be deduced by dividing by the depth.
Since 365605cf42, materials and layers are represented in a tree
structure that allows traversing up through parents and iterating down
through children. This re-works the related typedefs and reparenting
code so that they can be shared.
Previously cogl_set_fog would cause a flush of the Cogl journal and
would directly bang the GL state machine to setup fogging. As part of
the ongoing effort to track most state in CoglMaterial to support
renderlists this now adds an indirection so that cogl_set_fog now just
updates ctx->legacy_fog_state. The fogging state then gets enabled as a
legacy override similar to how the old depth testing API is handled.
The commit to split the fragment processing backends out from
cogl-material.c (3e1323a636) broke the GLES 1 and 2 builds the
fix was to guard the code in each backend according to the
COGL_MATERIAL_BACKEND_XYZ defines which are setup in
cogl-material-private.h.
This splits the fragment processing backends (glsl, arbfp and fixed) out
from cogl-material.c into their own cogl-material-{glsl,arbfp,fixed}.c
files in an effort to help and keep cogl-material.c maintainable.
