This allows _cogl_material_flush_gl_state to bail out faster if
repeatedly asked to flush the same material and we can see the material
hasn't changed.
Since we can rely on the material age incrementing when any material
property changes or any associated layer property changes then we can
track the age of the material after flushing so it can be compared with
the age of the material if it is subsequently re-flushed. If the age is
the same we only have to re-assert the texture object state.
This merges the two implementations of CoglProgram for the GLES2 and
GL backends into one. The implementation is more like the GLES2
version which would track the uniform values and delay sending them to
GL. CoglProgram is now effectively just a GList of CoglShaders along
with an array of stored uniform values. CoglProgram never actually
creates a GL program, instead this is left up to the GLSL material
backend. This is necessary on GLES2 where we may need to relink the
user's program with different generated shaders depending on the other
emulated fixed function state. It will also be necessary in the future
GLSL backends for regular OpenGL. The GLSL and ARBfp material backends
are now the ones that create and link the GL program from the list of
shaders. The linked program is attached to the private material state
so that it can be reused if the CoglProgram is used again with the
same material. This does mean the program will get relinked if the
shader is used with multiple materials. This will be particularly bad
if the legacy cogl_program_use function is used because that
effectively always makes one-shot materials. This problem will
hopefully be alleviated if we make a hash table with a cache of
generated programs. The cogl program would then need to become part of
the hash lookup.
Each CoglProgram now has an age counter which is incremented every
time a shader is added. This is used by the material backends to
detect when we need to create a new GL program for the user program.
The internal _cogl_use_program function now takes a GL program handle
rather than a CoglProgram. It no longer needs any special differences
for GLES2. The GLES2 wrapper function now also uses this function to
bind its generated shaders.
The ARBfp shaders no longer store a copy of the program source but
instead just directly create a program object when cogl_shader_source
is called. This avoids having to reupload the source if the same
shader is used in multiple materials.
There are currently a few gross hacks to get the GLES2 backend to work
with this. The problem is that the GLSL material backend is now
generating a complete GL program but the GLES2 wrapper still needs to
add its fixed function emulation shaders if the program doesn't
provide either a vertex or fragment shader. There is a new function in
the GLES2 wrapper called _cogl_gles2_use_program which replaces the
previous cogl_program_use implementation. It extracts the GL shaders
from the GL program object and creates a new GL program containing all
of the shaders plus its fixed function emulation. This new program is
returned to the GLSL material backend so that it can still flush the
custom uniforms using it. The user_program is attached to the GLES2
settings struct as before but its stored using a GL program handle
rather than a CoglProgram pointer. This hack will go away once the
GLSL material backend replaces the GLES2 wrapper by generating the
code itself.
Under Mesa this currently generates some GL errors when glClear is
called in test-cogl-shader-glsl. I think this is due to a bug in Mesa
however. When the user program on the material is changed the GLSL
backend gets notified and deletes the GL program that it linked from
the user shaders. The program will still be bound in GL
however. Leaving a deleted shader bound exposes a bug in Mesa's
glClear implementation. More details are here:
https://bugs.freedesktop.org/show_bug.cgi?id=31194
*** WARNING: THIS COMMIT CHANGES THE BUILD ***
Do not recurse into the backend directories to build private, internal
libraries.
We only recurse from clutter/ into the cogl sub-directory; from there,
we don't recurse any further. All the backend-specific code in Cogl and
Clutter is compiled conditionally depending on the macros defined by the
configure script.
We still recurse from the top-level directory into doc, clutter and
tests, because gtk-doc and tests do not deal nicely with non-recursive
layouts.
This change makes Clutter compile slightly faster, and cleans up the
build system, especially when dealing with introspection data.
Ideally, we also want to make Cogl part of the top-level build, so that
we can finally drop the sed trick to change the shared library from the
GIR before compiling it.
Currently disabled:
‣ OSX backend
‣ Fruity backend
Currently enabled but untested:
‣ EGL backend
‣ Windows backend
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.
The special handling for texture unit 1 caught the case where unit
1 was changed for transient purposes, but didn't properly handle
the case where the actual non-transient texture was different between
two materials with no transient binding in between.
If the actual texture has changed when flushing, mark unit 1 as dirty
and needing a rebind.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2261
In _cogl_material_texture_storage_change_notify we were potentially
dereferencing layer->texture without checking first that it is the
authority of texture state. We now use
_cogl_material_layer_get_texture() instead.
This makes the gles2 cogl_program_use consistent with the GL version by
not binding the program immediately and instead leaving it to
cogl-material.c to bind the program when actually drawing something.
In OpenGL the 'shininess' lighting parameter is floating point value
limited to the range 0.0→128.0. This number is used to affect the size
of the specular highlight. Cogl materials used to only accept a number
between 0.0 and 1.0 which then gets multiplied by 128.0 before sending
to GL. I think the assumption was that this is just a weird GL quirk
so we don't expose it. However the value is used as an exponent to
raise the attenuation to a power so there is no conceptual limit to
the value.
This removes the mapping and changes some of the documentation.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2222
When flushing a fixed-function or arbfp material it would always call
disable_glsl to try to get rid of the previous GLSL shader. This is
needed even if current_use_program_type is not GLSL because if an
application calls cogl_program_uniform then Cogl will have to bind the
program to set the uniform. If this happens then it won't update
current_use_program_type presumably because the enabled state of arbfp
is still valid.
The problem was that disable_glsl would only select program zero when
the current_use_program_type is set to GLSL which wouldn't be the case
if cogl_program_uniform was called. This patch changes it to just
directly call _cogl_gl_use_program_wrapper(0) instead of having a
separate disable_glsl function. The current program is cached in the
cogl context anyway so it shouldn't cause any extra unnecessary GL
calls.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2232
This moves the code supporting _cogl_material_flush_gl_state into
cogl-material-opengl.c as part of an effort to reduce the size of
cogl-material.c to keep it manageable.
In general cogl-material.c has become far to large to manage in one
source file. As one of the ways to try and break it down this patch
starts to move some of lower level texture unit state management out
into cogl-material-opengl.c. The naming is such because the plan is to
follow up and migrate the very GL specific state flushing code into the
same file.
