Previously we tracked whether the clip stack needs flushing as part of
the CoglClipState which is part of the CoglFramebuffer state. This is
a bit odd because most of the clipping state (such as the clip planes
and the scissor) are part of the GL context's state rather than the
framebuffer. We were marking the clip state on the framebuffer dirty
every time we change the framebuffer anyway so it seems to make more
sense to have the dirtiness be part of the global context.
Instead of a just a single boolean to record whether the state needs
flushing, the CoglContext now holds a reference to the clip stack that
was flushed. That way we can flush arbitrary stack states and if it
happens to be the same as the state already flushed then Cogl will do
nothing. This will be useful if we log the clip stack in the journal
because then we will need to flush unrelated clip stack states for
each batch.
Instead of having a separate CoglHandle for CoglClipStack the code is
now expected to directly hold a pointer to the top entry on the
stack. The empty stack is then the NULL pointer. This saves an
allocation when we want to copy the stack because we can just take a
reference on a stack entry. The idea is that this will make it
possible to store the clip stack in the journal without any extra
allocations.
The _cogl_get_clip_stack and set functions now take a CoglClipStack
pointer instead of a handle so it would no longer make sense to make
them public. However I think the only reason we would have wanted that
in the first place would be to save the clip state between switching
FBOs and that is no longer necessary.
CoglVertexAttribute has an internal draw function that is used by the
CoglJournal to avoid the call to cogl_journal_flush which would
otherwise end up recursively flushing the journal forever. The
enable_gl_state function called by this was previously also calling
_cogl_flush_framebuffer_state. However the journal code tries to
handle this function specially by calling it with a flag to disable
flushing the modelview matrix. This is useful because the journal
handles flushing the modelview itself. Without this patch the journal
state ends up getting flushed twice. This isn't a particularly big
problem currently because the matrix stack has caching to recognise
when it would push the same state twice and bails out. However if we
later want to use the framebuffer flush flags to override a particular
state of the framebuffer (such as the clip state) then we need to make
sure the flush isn't called twice.
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.
The convenience constructors for the builtin vertex structs were
creating the primitive and then immediately destroying it and
returning the pointer. I think the intention was to unref the
attributes instead. This adds an internal wrapper around the
new_with_attributes_array constructor which unrefs the attributes
instead of the primitive. The convenience constructors now use that.
The GLES2 wrapper was referring to COGL_MATERIAL_PROGRAM_TYPE_GLSL but
this has since been renamed to COGL_PIPELINE_PROGRAM_TYPE_GLSL so the
GLES2 backend wouldn't compile.
The gles2 wrapper functions don't understand about the CoglBuffer API so
they don't support attributes stored in a CoglVertexArray. Instead of
teaching the backend about buffers we are going to wait until we have
overhauled the GLES 2 backend. We are currently making progress
consolidating the GLES 2 backend with a new GLSL backend for
CoglMaterial. This will hugely simplify the GLES 2 support and share
code with the OpenGL backend. In the end it's hoped that this problem
will simply go away so it doesn't make much sense to solve it with the
current design.
This applies an API naming change that's been deliberated over for a
while now which is to rename CoglMaterial to CoglPipeline.
For now the new pipeline API is marked as experimental and public
headers continue to talk about materials not pipelines. The CoglMaterial
API is now maintained in terms of the cogl_pipeline API internally.
Currently this API is targeting Cogl 2.0 so we will have time to
integrate it properly with other upcoming Cogl 2.0 work.
The basic reasons for the rename are:
- That the term "material" implies to many people that they are
constrained to fragment processing; perhaps as some kind of high-level
texture abstraction.
- In Clutter they get exposed by ClutterTexture actors which may be
re-inforcing this misconception.
- When comparing how other frameworks use the term material, a material
sometimes describes a multi-pass fragment processing technique which
isn't the case in Cogl.
- In code, "CoglPipeline" will hopefully be a much more self documenting
summary of what these objects represent; a full GPU pipeline
configuration including, for example, vertex processing, fragment
processing and blending.
- When considering the API documentation story, at some point we need a
document introducing developers to how the "GPU pipeline" works so it
should become intuitive that CoglPipeline maps back to that
description of the GPU pipeline.
- This is consistent in terminology and concept to OpenGL 4's new
pipeline object which is a container for program objects.
Note: The cogl-material.[ch] files have been renamed to
cogl-material-compat.[ch] because otherwise git doesn't seem to treat
the change as a moving the old cogl-material.c->cogl-pipeline.c and so
we loose all our git-blame history.
This updates the implementation of cogl_polygon so it sits on the new
CoglVertexArray and CoglVertexAttribute apis. This lets us minimize the
number of different drawing paths we have to maintain in Cogl.
Since the sliced texture support for cogl_polygon has been broken for a
long time now and no one has complained this patch also greatly
simplifies the code by not doing any special material validation so
cogl_polygon will be restricted in the same way as
cogl_draw_vertex_attributes. (i.e. sliced textures not supported).
Instead of using raw OpenGL in the journal we now use the vertex
attributes API instead. This is part of an ongoing effort to reduce the
number of drawing paths we maintain in Cogl.
The functionality of cogl_vertex_buffer_indices_get_for_quads is now
provided by cogl_get_rectangle_indices so this reworks the former to now
work in terms of the latter so we don't have duplicated logic.
As part of an ongoing effort to reduce the number of draw paths we have
in Cogl this re-works CoglVertexBuffer to use the CoglVertexAttribute
and CoglPrimitive APIs instead of using raw GL.
This adds a way to mark that a primitive is in use so that modifications
will generate a warning. The plan is to use this mechanism when batching
primitives in the journal to warn users that mid-scene modifications of
primitives is not allowed.
This adds convenience primitive constructors named like:
cogl_primitive_new_p3 or
cogl_primitive_new_p3c4 or
cogl_primitive_new_p3t2c4
where the letters correspond to the interleved vertex attributes layouts
such as CoglP3Vertex which is a struct with 3 float x,y,z members for
the [p]osition, or CoglP3T2C4Vertex which is a struct with 3 float x,y,z
members for the [p]osition, 2 float s,t members for the [t]exture
coordinates and 4 unsigned byte r,g,b,a members for the [c]olor.
The hope is that people will find these convenient enough to replace
cogl_polygon.
A CoglPrimitive is a retainable object for drawing a single primitive,
such as a triangle strip, fan or list.
CoglPrimitives build on CoglVertexAttributes and CoglIndices which
themselves build on CoglVertexArrays and CoglIndexArrays respectively.
A CoglPrimitive encapsulates enough information such that it can be
retained in a queue (e.g. the Cogl Journal, or renderlists in the
future) and drawn at some later time.
A CoglVertexAttribute defines a single attribute contained in a
CoglVertexArray. I.e. a CoglVertexArray is simply a buffer of N bytes
intended for containing a collection of attributes (position, color,
normals etc) and a CoglVertexAttribute defines one such attribute by
specifying its start offset in the array, its type, the number of
components and the stride etc.
CoglIndices define a range of indices inside a CoglIndexArray. I.e. a
CoglIndexArray is simply a buffer of N bytes and you can then
instantiate multiple CoglIndices collections that define a sub-region of
a CoglIndexArray by specifying a start offset and an index data type.
This adds a new CoglVertexArray object which is a subclass of CoglBuffer
used to hold vertex attributes. A later commit will add a
CoglVertexAttribute API which will be used to describe the attributes
inside a CoglVertexArray.
A CoglIndexArray is a subclass of CoglBuffer and will be used to hold
vertex indices. A later commit will add a CoglIndices API which will
allow describing a range of indices inside a CoglIndexArray.
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 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.
MaterialNodes are used for the sparse graph of material state and layer
state. In the case of materials there is the idea of weak materials that
don't take a reference on their parent and in that case we need to be
careful not to unref our parent during
_cogl_material_node_unparent_real. This adds a has_parent_reference
member to the CoglMaterialNode struct so we now know when to skip the
unref.
If there is private data associated with a CoglObject then there may be
a user_data_array that needs to be freed. The code was mistakenly
freeing the array inside the loop that was actually iterating over the
user data array notifying the objects destruction instead of waiting
until all the data entries had been destroyed.
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
Previously cogl_set_source_color and cogl_set_source_texture modified
a single global material. If an application then mixes using
cogl_set_source_color and texture then the material will constantly
need a new ARBfp program because the numbers of layers alternates
between 0 and 1. This patch just adds a second global material that is
only used for cogl_set_source_texture. I think it would still end up
flushing the journal if cogl_set_source_texture is used with multiple
different textures but at least it should avoid a recompile unless the
texture target also changes. It might be nice to somehow attach a
material to the CoglTexture for use with cogl_set_source_texture but
it would be difficult to implement this without creating a circular
reference.
This moves the CoglIndicesType and CoglVerticesMode typedefs from
cogl-vertex-buffer.h to cogl-types.h so they can be shared with the
anticipated cogl vertex attribute API.
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.
This is a counter part for _cogl_material_layer_get_texture which takes
a layer index instead of a direct CoglMaterialLayer pointer. The aim is
to phase out code that directly iterates the internal layer pointers of
a material since the layer pointers can change if any property of any
layer is changed making direct layer pointers very fragile.
This adds internal _cogl_material_get_layer_filters and
_cogl_material_get_layer_{min,mag}_filter functions which can be used to
query the filters associated with a layer using a layer_index, as
opposed to a layer pointer. Accessing layer pointers is considered
deprecated so we need to provide layer_index based replacements.
When we come to submitting the users given attributes we sort them into
different types of buffers. Previously we had three types; strided,
unstrided and multi-pack. Really though unstrided was just a limited
form of multi-pack buffer and didn't imply any hind of special
optimization so this patch consolidates some code by reducing to just
two types; strided and multi-pack.
This is a counter part for _cogl_material_layer_pre_paint which takes a
layer index instead of a direct CoglMaterialLayer pointer. The aim is to
phase out code that directly iterates the internal layer pointers of a
material since the layer pointers can change if any property of any
layer is changed making direct layer pointers very fragile.
This exposes the idea of a stack of source materials instead of just
having a single current material. This allows the writing of orthogonal
code that can change the current source material and restore it to its
previous state. It also allows the implementation of new composite
primitives that may want to validate the current source material and
possibly make override changes in a derived material.
When compiling for non-glx platforms the winsys feature data array
ends up empty. Empty arrays cause problems for MSVC so this patch adds
a stub entry so that the array always has at least one entry.
Based on a patch by Ole André Vadla Ravnås
Instead of directly manipulating GL textures itself,
CoglTexture2DSliced now works in terms of CoglHandles. It creates the
texture slices using cogl_texture_new_with_size which should always
end up creating a CoglTexture2D because the size should fit. This
allows us to avoid replicating some code such as the first pixel
mipmap tracking and it better enforces the separation that each
texture backend is the only place that contains code dealing with each
texture target.
This adds two new internal functions to create a foreign texture for
the texture 2d and rectangle backends. cogl_texture_new_from_foreign
will now use one of these backends directly if there is no waste
instead of always using the sliced texture backend.
When picking a size for the last slice in a texture, Cogl would always
pick the biggest power of two size that doesn't create too much
waste and is less than or equal to the previous slice size. However
this can end up creating a texture that is bigger than needed if there
is a smaller power of two.
For example, if the maximum waste is 127 (the current default) and we
try to create a texture that is 257 pixels wide it will decide that
the next power of two (512) is too much waste (255) so it will create
the first slice at 256 pixels wide. Then we only have 1 pixel left to
allocate but Cogl would pick the next smaller size that has a small
enough waste which is 128. But of course 1 is already a power of two
so that's redundantly oversized by 127.
This patch fixes it so that whenever it finds a size that would be big
enough, instead of using exactly that it picks the next power of two
up from the size we need to fill.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2355
