This is part of a broader cleanup of some of the experimental Cogl API.
One of the reasons for this particular rename is to switch away from
using the term "Array" which implies a regular, indexable layout which
isn't the case. We also want to strongly imply a relationship between
CoglBuffers and CoglPixelBuffers and be consistent with the
CoglAttributeBuffer and CoglIndexBuffer APIs.
This is part of a broader cleanup of some of the experimental Cogl API.
One of the reasons for this particular rename is to switch away from
using the term "Array" which implies a regular, indexable layout which
isn't the case. We also want to have a strongly implied relationship
between CoglAttributes and CoglAttributeBuffers.
GLES has an extension called GL_OES_mapbuffer to support mapping
buffer objects but only for writing. Cogl now has two new feature
flags to advertise whether mapping for reading and writing is
supported. Under OpenGL, these features are always set if the VBO
extension is advertised and under GLES only the write flag is set if
the GL_OES_mapbuffer extension is advertised.
In the journal code and when generating the stroke path the vertices
are generated on the fly and stored in a CoglBuffer using
cogl_buffer_map. However cogl_buffer_map is allowed to fail but it
wasn't checking for a NULL return value. In particular on GLES it will
always fail because glMapBuffer is only provided by an extension. This
adds a new pair of internal functions called
_cogl_buffer_{un,}map_for_fill_or_fallback which wrap
cogl_buffer_map. If the map fails then it will instead return a
pointer into a GByteArray attached to the context. When the buffer is
unmapped the array is copied into the buffer using
cogl_buffer_set_data.
The GLES2 wrapper is no longer needed because the shader generation is
done within the GLSL fragend and vertend and any functions that are
different for GLES2 are now guarded by #ifdefs.
With the refactoring to centralize code into CoglBuffer,
_cogl_buffer_fini() was never actually implemented, so all GL
vertex and index buffer objects were leaked.
The duplicate call to glDeleteBuffers() in CoglPixelArray is
removed (it wasn't paying attention to whether the buffer had been
allocated as a PBO or not.)
http://bugzilla.clutter-project.org/show_bug.cgi?id=2423
Unless the CoglBuffer is being used for texture data then it's
relatively unlikely that the data will contain an array of bytes. For
example if it's used as a vertex array then it's more likely to be
floats or some vertex struct. In that case it's much more convenient
if set_data and map use void* pointers so that we can avoid a cast.
This adds an internal mechanism to mark that a buffer is in-use so that
a warning can be generated if the user attempts to modify the buffer.
The plans is for the journal to use this mechanism so that we can warn
users about mid-scene modifications of buffers.
We now make _cogl_buffer_bind return a base pointer for the bound buffer
which can be used with OpenGL. The pointer will be NULL for GPU based
buffers or may point to an malloc'd buffer. Since OpenGL expects an
offset instead of a pointer when dealing with buffer objects this means
we can handle fallback malloc buffers and GPU buffers in a consistent
way.
This renames the BufferBindTarget + BufferUsageHint enums to match the
anticipated new APIs for "index arrays" and "vertex arrays" as opposed
to using the terms "vertices" or "indices".
previously we would silently bail out if the given offset + data size
would overflow the buffer size. Now we use g_return_val_if_fail so we
get a warning if we hit this case.
This adds a store_created bit field to CoglBuffer so we know if the
underlying buffer has been allocated yet. Previously the code was trying
to do something really wrong by accidentally using the
COGL_PIXEL_ARRAY_FLAG_IS_SET macro (note "PIXEL_ARRAY") and what is more
odd was the declaration of a CoglPixelArray *pixel_array in
cogl-buffer.c which the buffer was being cast too before calling using
the macro. Probably this was the fall-out of some previous code
re-factoring.
All the macros get used for are to |= (a new flag bit), &= ~(a flag bit)
or use the & operator to test if a flag bit is set. I haven't found the
code more readable with these macros, but several times now I've felt
the need to double check if these macros do anything else behind the
hood or I've forgotten what flags are available so I've had to go to the
macro definition to see what the full enum names are for the flags (the
macros use symbol concatenation) so I can search for the definition of
all the flags. It turns out they are defined next to the macro so you
don't have to search far, but without the macro that wouldn't have been
necessary.
The more common use of the _IS_SET macro is actually more concise
expanded and imho since it doesn't hide anything in a separate header
file the code is more readable without the macro.
Since we'll want to share the fallback logic with CoglVertexArray this
moves the malloc based fallback (for when OpenGL doesn't support vertex
or pixel buffer objects) into cogl-buffer.c.
Explicitly warn if we detect that a CoglBuffer is being freed while it
is still mapped. Previously we silently unmapped the buffer, but it's
not something we want to encourage.
This makes CoglBuffer track the last used bind target as a private
property. This is later used when binding a buffer to map instead of
always using the PIXEL_UNPACK target.
This also adds some additional sanity checks that code doesn't try to
nest binds to the same target or bind a buffer to multiple targets at
the same time.
This allows you to tell Cogl that you are planning to replace all the
buffer's data once it is mapped with cogl_buffer_map. This means if the
buffer is currently being accessed by the GPU then the driver doesn't
have to stall and wait for it to finish before it can access it from the
CPU and can instead potentially allocate a new buffer with undefined
data and map that.
The usage hint should be implied by the CoglBuffer subclass type so the
public getter and setter APIs for manually changing the usage hint of a
CoglBuffer have now been removed.
Instead of having to extend cogl_is_buffer with new buffer types
manually this now adds a new COGL_BUFFER_DEFINE macro to be used instead
of COGL_OBJECT_DEFINE for CoglBuffer subclasses. This macro will
automatically register the new type with ctx->buffer_types which will
iterated by cogl_is_buffer. This is the same coding pattern used for
CoglTexture.
We had several different ways of exposing experimental API, in one case
the symbols had no special suffix, in two other ways the symbols were
given an _EXP suffix but in different ways.
This makes all experimental API have an _EXP suffix which is handled
using #defines in the header so the prototypes in the .c and .h files
don't have the suffix.
The documented reason for the suffix is so that anyone watching Cogl for
ABI changes who sees symbols disappear will hopefully understand what's
going on.
As part of an effort to improve the architecture of CoglMaterial
internally this overhauls how we flush layer state to OpenGL by adding a
formal backend abstraction for fragment processing and further
formalizing the CoglTextureUnit abstraction.
There are three backends: "glsl", "arbfp" and "fixed". The fixed backend
uses the OpenGL fixed function APIs to setup the fragment processing,
the arbfp backend uses code generation to handle fragment processing
using an ARBfp program, and the GLSL backend is currently only there as
a formality to handle user programs associated with a material. (i.e.
the glsl backend doesn't yet support code generation)
The GLSL backend has highest precedence, then arbfp and finally the
fixed. If a backend can't support some particular CoglMaterial feature
then it will fallback to the next backend.
This adds three new COGL_DEBUG options:
* "disable-texturing" as expected should disable all texturing
* "disable-arbfp" always make the arbfp backend fallback
* "disable-glsl" always make the glsl backend fallback
* "show-source" show code generated by the arbfp/glsl backends
While this is totally fine (0 in the pointer context will be converted
in the right internal NULL representation, which could be a value with
some bits to 1), I believe it's clearer to use NULL in the pointer
context.
It seems that, in most case, it's more an overlook than a deliberate
choice to use FALSE/0 as NULL, eg. copying a _COGL_GET_CONTEXT (ctx, 0)
or a g_return_val_if_fail (cond, 0) from a function returning a
gboolean.
This replaces the use of CoglHandle with strongly type CoglBuffer *
pointers instead. The only function not converted for now is
cogl_is_buffer which will be done in a later commit.
Since using addresses that might change is something that finally
the FSF acknowledge as a plausible scenario (after changing address
twice), the license blurb in the source files should use the URI
for getting the license in case the library did not come with it.
Not that URIs cannot possibly change, but at least it's easier to
set up a redirection at the same place.
As a side note: this commit closes the oldes bug in Clutter's bug
report tool.
http://bugzilla.openedhand.com/show_bug.cgi?id=521
In the frenzy of the last 10mins before API freeze, I obviously forgot
to update the OpenGL path for _cogl_buffer_hints_to_gl_enum(). This
commit fixes this.
We've had complaints that our Cogl code/headers are a bit "special" so
this is a first pass at tidying things up by giving them some
consistency. These changes are all consistent with how new code in Cogl
is being written, but the style isn't consistently applied across all
code yet.
There are two parts to this patch; but since each one required a large
amount of effort to maintain tidy indenting it made sense to combine the
changes to reduce the time spent re indenting the same lines.
The first change is to use a consistent style for declaring function
prototypes in headers. Cogl headers now consistently use this style for
prototypes:
return_type
cogl_function_name (CoglType arg0,
CoglType arg1);
Not everyone likes this style, but it seems that most of the currently
active Cogl developers agree on it.
The second change is to constrain the use of redundant glib data types
in Cogl. Uses of gint, guint, gfloat, glong, gulong and gchar have all
been replaced with int, unsigned int, float, long, unsigned long and char
respectively. When talking about pixel data; use of guchar has been
replaced with guint8, otherwise unsigned char can be used.
The glib types that we continue to use for portability are gboolean,
gint{8,16,32,64}, guint{8,16,32,64} and gsize.
The general intention is that Cogl should look palatable to the widest
range of C programmers including those outside the Gnome community so
- especially for the public API - we want to minimize the number of
foreign looking typedefs.
OpenGL ES has no PBO extension, so we fallback to using a malloc'ed
buffer. Make sure the OpenGL-only defines don't leak into the OpenGL ES
compilation.
Buffer objects are cool! This abstracts the buffer API first introduced
by GL_ARB_vertex_buffer_object and then extended to other objects.
The coglBuffer abstract class is intended to be the base class of all
the buffer objects, letting the user map() buffers. If the underlying
implementation does not support buffer objects (or only support VBO but
not FBO for instance), fallback paths should be provided.
