If a single arbfp program is being shared between multiple CoglMaterials
then we need to make sure we update all program.local params when
switching between materials. Previously we had a dirty flag to track
when combine_constant params were changed but didn't take in to account
that different materials sharing the same program may have different
combine constants.
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 now pass a boolean to _cogl_material_pre_change_notify to know when
a material change is as a result of a layer change. We plan to use this
information to avoid notifying the backends about material changes if
they are as a result of layer changes. This will simplify the handling
of state changes in the backends because they can assume that layer and
material changes are mutually exclusive.
This adds an internal _cogl_material_get_layer_combine_constant function
so we can query the current layer combine constant back. We should
probably make this a public property getter, but for now we just need
this so we can read the constant in the arbfp backend.
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 avoids the use of of gcc constructor and destructor attributes to
initialize the cogl uprof context and optionally print a cogl uprof
report at app exit. We now initialize the uprof context in
cogl_context_create instead.
When building with --enable-profile we now depend on the uprof-0.3
developer release which brings a few improvements:
» It lets us "fix" how we initialize uprof so that instead of using a shared
object constructor/destructor (which was a hack used when first adding
uprof support to Clutter) we can now initialize as part of clutter's
normal initialization code. As a side note though, I found that the way
Clutter initializes has some quite serious problems whenever it
involves GOptionGroups. It is not able to guarantee the initialization
of dependencies like uprof and Cogl. For this reason we still use the
contructor/destructor approach to initialize uprof in Cogl.
» uprof-0.3 provides a better API for adding custom columns when reporting
timer and counter statistics which lets us remove quite a lot of manual
report generation code in clutter-profile.c.
» uprof-0.3 provides a shared context for tracking mainloop timer
statistics. This means any mainloop based library following the same
"Mainloop" timer naming convention can use the shared context and no
matter who ends up owning the final mainloop the statistics will always
be in the same place. This allows profiling of Clutter with an
external mainloop such as with the Mutter compositor.
» uprof-0.3 can export statistics over dbus and comes with an ncurses
based ui to vizualize timer and counter stats live.
The latest version of uprof can be cloned from:
git://github.com/rib/UProf.git
When try_creating_fbo fails it deletes any intermediate render buffers
that were created. However it doesn't clear the list so I think if it
failed a second time it would try to delete the render buffers
again. This could potentially cause problems if a subsequent fbo is
created because the destructor for the original might delete the
renderbuffers of the new fbo.
Let's try to keep Cogl's build as non-recursive as possible, in the hope
that one day we'll be able to make it fully non-recursive along with the
rest of Clutter.
Flushing the framebuffer state can cause some drawing to occur if the
framebuffer has a clip stack which needs the stencil buffer. This was
causing the array pointers set up by enable_state_for_drawing_buffer
to get mangled so it would crash when it hits glDrawArrays. This patch
moves the framebuffer state flush to before it sets up the array
pointers.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2297
When disposing a material layer of type 'texture' we should check that
the texture handle is still valid before calling cogl_handle_unref().
This avoids an assertion failure when disposing a ClutterTexture.
This patch merges in substantial work from
Emmanuele Bassi <ebassi@linux.intel.com>
* Use new introspection --include-uninstalled API since we don't want
to try to find the clutter-1.0.pc file before it's installed.
* Use --pkg-export for Clutter-1.0.gir, since we want the .gir file to
contain the associated pkg-config file.
* Drop the use of --pkg for dependencies; those come from the associated
.gir files. (Actually, --pkg is almost never needed)
* Add --quiet
http://bugzilla.clutter-project.org/show_bug.cgi?id=2292
Intel CE3100 and CE4100 SoCs are designed for TVs. They have separate
framebuffers that are blended together by a piece of hardware to make
the final output. The library that allows you to initialize and
configure those planes is called GDL. A EGL GDL winsys can then be
use with those planes as NativeWindowType to select which plane to use.
This patch adds a new ClutterBackendCex100 backend that can be
selected at compile time with the new --with-flavour=cex100 option.
Some minor fixes here and there: missing include, wrongly placed #endif,
unused variable warning fixes, missing #ifdef.
Make ClutterStageEGL a subclass of either ClutterStageX11 or GObject
depending if you compile with X11 support (EGLX) or not (native).
Weak materials are ones that don't take a reference on their parent and
they are associated with a callback that notifies when the material is
destroyed, because its parent was freed or modified.
More details can be found at:
http://wiki.clutter-project.org/wiki/CoglDesign/CoglMaterial
For now the concept is internal only but the plan is to make this public
at some point once we have tested the design internally.
In the case where there is no error log for arbfp we were returning a
"" string literal. The other paths were using g_strdup to return a
string that could be freed with g_free. This makes the arbfp path return
g_strdup ("") instead.
There are quite a few if {} else {} blocks for dealing with arbfp else
glsl and the first block is guarded with #ifdef HAVE_COGL_GL. In this
case though the #endif was before the else so it wouldn't compile for
gles.
We need to include cogl-shader-private.h to have the
COGL_SHADER_TYPE_GLSL define. When building for opengl this wasn't
noticed probably because some other header indirectly includes this
file. It was a problem when building for gles2 though.
Instead of exposing an API that provides an OpenGL state machine style
where you first have to bind the program to the context using
cogl_program_use() followed by updating uniforms using
cogl_program_uniform_xyz we now have uniform setter methods that take an
explicit CoglHandle for the program.
This deprecates cogl_program_use and all the cogl_program_uniform
variants and provides the following replacements:
cogl_program_set_uniform_1i
cogl_program_set_uniform_1f
cogl_program_set_uniform_int
cogl_program_set_uniform_float
cogl_program_set_uniform_matrix
--quiet has been added to g-ir-scanner in the 0.9.1 cycle. We really
want to be able to compile clutter with 0.6.14 to be able to reuse
gir files that are distributed in current distributions.
Use the INTROSPECTION_SCANNER_ARGS (previously unused) variable to
convey --quiet when necessary.
Fixes: http://bugzilla.clutter-project.org/show_bug.cgi?id=2265
CoglAtlas chooses a fairly large default initial size of either
512x512 or 1024x1024 depending on the texture format. There is a
chance that this size will not be supported on some platforms which
would be catastrophic for the glyph cache because it would mean that
it would always fail to put any glyphs in the cache so text wouldn't
work. To fix this the atlas code now checks whether the chosen initial
size is supported by the texture driver and if not it will get halved
until it is supported.
Previously when creating a new rectangle map it would try increasingly
larger texture sizes until GL_MAX_TEXTURE_SIZE is reached. This is bad
because it queries state which should really be owned by the texture
driver. Also GL_MAX_TEXTURE_SIZE is often a conservative estimate so
larger texture sizes can be used if the proxy texture is queried
instead.
Previously each node in the rectangle map tree would store the total
remaining space in all of its children to use as an optimization when
adding nodes. With this it could skip an entire branch of the tree if
it knew there could never be enough space for the new node in the
branch. This modifies that slightly to instead store the largest
single gap. This allows it to skip a branch earlier because often
there would be a lot of small gaps which would add up to enough a
space for the new rectangle, but the space can't be used unless it is
in a single node.
The rectangle map still needs to keep track of the total remaining
space for the whole map for the debugging output so this has been
added back in to the CoglRectangleMap struct. There is a separate
debugging function to verify this value.
Previously when the atlas needs to be migrated it would start by
trying with the same size as the existing atlas if there is enough
space for the new texture. However even if the atlas is completely
sorted there will always be some amount of waste so when the atlas
needs to grow it would usually end up redundantly trying the same size
when it is very unlikely to fit. This patch changes it so that there
must be at least 6% waste available after the new texture is added
otherwise it will start with the next atlas size.
When iterating over the rectangle map a stack is used to implement a
recursive algorithm. Previously this was slice allocating a linked
list. Now it uses a GArray which is retained with the rectangle map to
avoid frequent allocations which is a little bit faster.
Previously the remaining space was managed as part of the
CoglRectangleMap struct. Now it is stored per node so that at any
point in the hierarchy we can quickly determine how much space is
remaining in all of the node's children. That way when adding a
rectangle we can miss out entire branches more quickly if we know that
there is no way the new rectangle would fit in that branch.
This also adds a function to recursively verify the cached state in
the nodes such as the remaining space and the number of
rectangles. This function is only called when the dump-atlas-image
debug flag is set because it is potentially quite slow.
_cogl_atlas_new now has two extra parameters to specify the format of
the textures it creates as well as a set of flags to modify the
behavious of the atlas. One of the flags causes the new textures to be
cleared and the other causes migration to avoid actually copying the
textures. This is needed to use CoglAtlas from the pango glyph cache
because it needs to use COGL_PIXEL_A_8 and to clear the textures as it
does not fill in the gaps between glyphs. It needs to avoid copying
the textures so that it can work on GL implementations without FBO
support.
Instead of storing a pointer to the CoglRectangleMap and a handle to
the atlas texture in the context, there is a now a separate data
structure called a CoglAtlas to manage these two. The context just
contains a pointer to this. The code to reorganise the atlas has been
moved from cogl-atlas-texture.c to cogl-atlas.c
This adds an internal CoglCallbackList type which is just a GSList of
of function pointers along with a data pointer to form a
closure. There are functions to add and remove items and to invoke the
list of functions. This could be used in a number of places in Cogl.
This simply renames CoglAtlas to CoglRectangleMap without making any
functional changes. The old 'CoglAtlas' is just a data structure for
managing unused areas of a rectangle and it doesn't neccessarily have
to be used for an atlas so it wasn't a very good name.
Textures within a layer were compared for equality by comparing their
texture handle. However this means that sub textures and atlas
textures which may be internally using the same GL handle would not be
batched together. Instead it now tries to determine the underlying GL
handle using either the slice override or _cogl_texture_get_gl_texture
and then compares those.
When filtering on allowed formats for atlas textures, it now masks out
the BGR and AFIRST bits in addition to the premult bit. That way it
will accept RGB and RGBA formats in any component order.
In theory it could also accept luminance and alpha-only textures but I
haven't added this because presumably if the application has requested
these formats then it has some reason not to use a full RGB or RGBA
texture and we should respect that.
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
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.
Previously we had an internal only _cogl_material_set_user_program to
redirect legacy usage of cogl_program_use() through CoglMaterial. This
instead makes the API public because until we implement our planned
"snippet" framework we need a stop-gap solution for using shaders in
Cogl.
The plan is to also support ARBfp with the cogl_program/shader API so
this API will also allow clutter-gst to stop using direct OpenGL calls
that conflict with Cogl's state tracking.
A change to a layer is also going to be a change to its owning material
so we have to chain up in _cogl_material_layer_pre_change_notify and
call _cogl_material_pre_change_notify. Previously we were only
considering if the owning material was referenced in the journal but
that ignores that it might also have dependants. We no longer need to
flush the journal directly in layer_pre_change_notify.
In _cogl_material_layer_pre_change_notify when we see that a layer has
dependants and it can't be modified directly then we allocate a new
layer. In this case we also have to link the new layer to its required
owner. If the immutable layer we copied had the same owner though we
weren't unlinking that old layer.
In _cogl_material_pre_change_notify we need to identify if it's a sparse
property being changed and if so initialize the state group if the given
material isn't currently the authority for it.
Previously we were unconditionally calling
_cogl_material_initialize_state which would e.g. NULL the layer
differences list of a material each time a layer change was notified.
It would also call _cogl_material_initialize_state for non-sparse
properties which should always be valid at this point so the function
has been renamed to _cogl_material_initialize_sparse_state to make this
clearer with a corresponding g_return_if_fail check.
This fixes how we copy layer differences in
_cogl_material_copy_layer_differences.
We were making a redundant g_list_copy of the src differences and then
iterating the src list calling _cogl_material_add_layer_difference for
each entry which would double the list length, but the initial copy
directly referenced the original layers which wasn't correct.
Also we were initializing dest->n_layers before copying the layer
differences but the act of copying the differences will re-initialize
n_layers to 0 when adding the first layer_difference since it will
trigger a layer_pre_change_notify and since the dest material isn't yet
a STATE_LAYERS authority the state group is initialized before allowing
the change.
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 improve the dot file output available when calling
_cogl_debug_dump_materials_dot_file. The material graph now directly
points into the layer graph and the layers now show the texture unit
index.
When the texture is set on a layer so that it is back to the parent's
texture it would clear the texture change flag but it wouldn't unref
the texture. The free function for a material layer does not unref the
texture if the change flag is cleared so the texture would end up
leaking. This happens for ClutterTexture because it disposes the
texture by setting layer 0 of the material to COGL_INVALID_HANDLE
which ends up the same as the default material.
In _cogl_material_layer_pre_paint we were mistakenly dereferencing the
layer->texture member for the passed layer instead of dereferencing the
texture state authority which was causing crashes in some cases.
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.
Previously custom uniforms were tracked in _CoglGles2Wrapper but as part
of a process to consolidate the gl/gles2 shader code it seems to make
sense for this state to be tracked in the CoglProgram object instead.
http://bugzilla.o-hand.com/show_bug.cgi?id=2179
Instead of having to query GL and translate the GL enum into a
CoglShaderType each time cogl_shader_get_type is called we now keep
track of the type in CoglShader.
Nothing was storing the shader type when a shader was created so it
would get confused about whether it was a custom vertex or fragment
shader.
Also the 'type' member of CoglShader was a GLenum but the only place
that read it was treating it as if it was CoglShaderType. This changes
it be CoglShaderType.
When loading an RGB image GdkPixbuf will pad the rowstride so that the
beginning of each row is aligned to 4 bytes. This was causing us to
fallback to the code that copies the buffer. It is probably safe to
avoid copying the buffer if we can detect that the rowstride is simply
an alignment of the packed rowstride.
This also changes the copying fallback code so that it uses the
aligned rowstride. However it is now extremely unlikely that the
fallback code would ever be used.
In commit b780413e5a the GdkPixbuf loading code was changed so that
if it needs to copy the pixbuf then it would tightly pack it. However
it was still using the rowstride from the pixbuf so the image would
end up skewed. This fixes it to use the real rowstride.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2235
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
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 function creates a CoglBitmap which internally references a
CoglBuffer. The map and unmap functions will divert to mapping the
buffer. There are also now bind and unbind functions which should be
used instead of map and unmap whenever the data doesn't need to be
read from the CPU but will instead be passed to GL for packing or
unpacking. For bitmaps created from buffers this just binds the
bitmap.
cogl_texture_new_from_buffer now just uses this function to wrap the
buffer in a bitmap rather than trying to bind the buffer
immediately. This means that the buffer will be bound only at the
point right before the texture data is uploaded.
This approach means that using a pixel array will take the fastest
upload route if possible, but can still fallback to copying the data
by mapping the buffer if some conversion is needed. Previously it
would just crash in this case because the texture functions were all
passed a NULL pointer.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2112
The docs for GdkPixbuf say that the last row of the image won't
necessarily be allocated to the size of the full rowstride. The rest
of Cogl and possibly GL assumes that we can copy the bitmap with
memcpy(height*rowstride) so we previously would copy the pixbuf data
to ensure this. However if the rowstride is the same as bpp*width then
there is no way for the last row to be under-allocated so in this case
we can just directly upload from the gdk pixbuf. Now that CoglBitmap
can be created with a destroy function we can make it keep a reference
to the pixbuf and unref it during its destroy callback. GdkPixbuf
seems to always pack the image with no padding between rows even if it
is RGB so this should end up always avoiding the memcpy.
The fallback code for when we do have to copy the pixbuf is now
simplified so that it copies all of the rows in a single loop. We only
copy the useful region of each row so this should be safe. The
rowstride of the CoglBitmap is now always allocated to bpp*width
regardless of the rowstride of the pixbuf.
The CoglBitmap struct is now only defined within cogl-bitmap.c so that
all of its members can now only be accessed with accessor
functions. To get to the data pointer for the bitmap image you must
first call _cogl_bitmap_map and later call _cogl_bitmap_unmap. The map
function takes the same arguments as cogl_pixel_array_map so that
eventually we can make a bitmap optionally internally divert to a
pixel array.
There is a _cogl_bitmap_new_from_data function which constructs a new
bitmap object and takes ownership of the data pointer. The function
gets passed a destroy callback which gets called when the bitmap is
freed. This is similar to how gdk_pixbuf_new_from_data
works. Alternatively NULL can be passed for the destroy function which
means that the caller will manage the life of the pointer (but must
guarantee that it stays alive at least until the bitmap is
freed). This mechanism is used instead of the old approach of creating
a CoglBitmap struct on the stack and manually filling in the
members. It could also later be used to create a CoglBitmap that owns
a GdkPixbuf ref so that we don't necessarily have to copy the
GdkPixbuf data when converting to a bitmap.
There is also _cogl_bitmap_new_shared. This creates a bitmap using a
reference to another CoglBitmap for the data. This is a bit of a hack
but it is needed by the atlas texture backend which wants to divert
the set_region virtual to another texture but it needs to override the
format of the bitmap to ignore the premult flag.
The 'format' member of CoglTexture2DSliced is returned by
cogl_texture_get_format. All of the other backends return the internal
format of the GL texture in this case. However the sliced backend was
returning the format of the image data used to create the texture. It
doesn't make any sense to retain this information because it doesn't
necessarily indicate the format of the actual texture. This patch
changes it to store the internal format instead.
In ddb9016be4 the GL texture driver backend was changed to include
cogl-material-opengl-private.h instead of cogl-material-private.h.
However the gles texture backend was missed from this so it was giving
a compiler warning about using an undeclared function.
glTexSubImage3D was being called directly in cogl-texture-3d.c but the
function is only available since GL version 1.2 so on Windows it won't
be possible to directly link to it. Also under GLES it is only
available conditionally in an extension.
In ddb9016be4 the texture backends were changed to include
cogl-material-opengl-private.h instead of cogl-material-private.h.
However the 3D texture backend was missed from this so it was giving a
compiler warning about using an undeclared function.
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.
When the support for redirecting the legacy fog state through cogl
material was added in 9b9e764dc, the code to handle copying the fog
state in _cogl_material_copy_differences was missed.
The CoglTexture2DSliced backend has a fallback for when the
framebuffer extension is missing so it's not possible to use
glGenerateMipmap. This involves keeping a copy of the upper-left pixel
of the tex image so that we can temporarily enable GL_GENERATE_MIPMAP
on the texture object and do a sub texture update by reuploading the
contents of the first pixel. This patch copies that mechanism to the
2D and 3D backends. The CoglTexturePixel structure which was
previously internal to the sliced backend has been moved to
cogl-texture-private.h so that it can be shared.
Using 'r' to name the third component is problematic because that is
commonly used to represent the red component of a vector representing
a color. Under GLSL this is awkward because the texture swizzling for
a vector uses a single letter for each component and the names for
colors, textures and positions are synonymous. GLSL works around this
by naming the components of the texture s, t, p and q. Cogl already
effectively already exposes this naming because it exposes GLSL so it
makes sense to use that naming consistently. Another alternative could
be u, v and w. This is what Blender and Direct3D use. However the w
component conflicts with the w component of a position vertex.
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.
Under big GL, glext.h is included automatically by gl.h. However under
GLES this doesn't appear to happen so it has to be included explicitly
to get the defines for extensions. This patch changes the
clutter_gl_header to be called cogl_gl_headers and it can now take a
space seperated list of multiple headers. This is then later converted
to a list of #include lines which ends up cogl-defines.h. The gles2
and gles1 backends now add their respective ext header to this list.
There are many places in the texture backend that need to do
conversion using the CoglBitmap code. Currently none of these
functions can throw an error but they do return a value to indicate
failure. In future it would make sense if new texture functions could
throw an error and in that case they would want to use a CoglBitmap
error if the failure was due to the conversion. This moves the
internal CoglBitmap error from the quartz backend to be public in
cogl-bitmap.h so that it can be used in this way.
We can use this error in more unsupported situations than just when we
have a Cogl feature flag for the error. For example if a non-sliced
texture is created with dimensions that are too large then we could
throw this error. Therefore it seems good to rename to something more
general.
