For now this new define is simply an alias for
COGL_ENABLE_EXPERIMENTAL_API but the intention is that we will also use
it to start experimenting with changes that need to break the existing
Cogl API in incompatible ways.
We now prepend a set of defines to any given GLSL shader so that we can
define builtin uniforms/attributes within the "cogl" namespace that we
can use to provide compatibility across a range of the earlier versions
of GLSL.
This updates test-cogl-shader-glsl.c and test-shader.c so they no longer
needs to special case GLES vs GL when splicing together its shaders as
well as the blur, colorize and desaturate effects.
To get a feel for the new, portable uniform/attribute names here are the
defines for OpenGL vertex shaders:
#define cogl_position_in gl_Vertex
#define cogl_color_in gl_Color
#define cogl_tex_coord_in gl_MultiTexCoord0
#define cogl_tex_coord0_in gl_MultiTexCoord0
#define cogl_tex_coord1_in gl_MultiTexCoord1
#define cogl_tex_coord2_in gl_MultiTexCoord2
#define cogl_tex_coord3_in gl_MultiTexCoord3
#define cogl_tex_coord4_in gl_MultiTexCoord4
#define cogl_tex_coord5_in gl_MultiTexCoord5
#define cogl_tex_coord6_in gl_MultiTexCoord6
#define cogl_tex_coord7_in gl_MultiTexCoord7
#define cogl_normal_in gl_Normal
#define cogl_position_out gl_Position
#define cogl_point_size_out gl_PointSize
#define cogl_color_out gl_FrontColor
#define cogl_tex_coord_out gl_TexCoord
#define cogl_modelview_matrix gl_ModelViewMatrix
#define cogl_modelview_projection_matrix gl_ModelViewProjectionMatrix
#define cogl_projection_matrix gl_ProjectionMatrix
#define cogl_texture_matrix gl_TextureMatrix
And for fragment shaders we have:
#define cogl_color_in gl_Color
#define cogl_tex_coord_in gl_TexCoord
#define cogl_color_out gl_FragColor
#define cogl_depth_out gl_FragDepth
#define cogl_front_facing gl_FrontFacing
When converting the virtual coordinates of the underlying texture for
a slice to virtual coordinates for the whole texture it was using the
size and offset of the intersection as the size of the child
texture. This would be incorrect if the texture contains waste or the
texture coordinates are not the default. Instead the sliced foreach
function now passes the CoglSpan to the callback instead of the
intersection.
http://bugzilla.clutter-project.org/show_bug.cgi?id=2398
Previously in the tests/tools directory we build a disable-npots
library which was used as an LD_PRELOAD to trick Cogl in to thinking
there is no NPOT texture extension. This is a little awkward to use so
it seems much simpler to just define a COGL_DEBUG option to disable
npot textures.
In some micro-benchmarks testing journal throughput the list
manipulation jumps pretty high in the profile. This replaces the GSList
usage with a GArray instead which is effectively a grow only allocation
that means we avoid ongoing allocations while manipulating the stack
mid-scene.
During _cogl_pipeline_needs_blending_enabled we were always checking the
current lighting properties (ambient,diffuse,specular,emission) which
had a notable impact during micro-benchmarks that exercise journal
throughput of simple colored rectangles. This #if 0's the offending code
considering that Cogl doesn't actually support lighting currently and
when it actually does then we will be able to optimize this by avoiding
the checks when lighting is disabled.
When using cogl_set_source_color4ub there is a notable difference
between colors that require blending and those that dont. When trying to
modify the color of pipeline referenced by the journal we don't force a
flush of the journal unless the color change will also change the
blending state. By using two separate pipeline objects for handing
opaque or transparent colors we can avoid ever flushing the journal when
repeatedly using cogl_set_source_color and jumping between opaque and
transparent colors.
This reworks _cogl_texture_quad_multiple_primitives so instead of using
the CoglPipelineWrapModeOverrides mechanism to force the clamp to edge
repeat mode we now derive an override pipeline using cogl_pipeline_copy
instead. This avoids a relatively large, unconditional, memset.
This avoids using the wrap mode overrides mechanism to implement
_cogl_multitexture_quad_single_primitive which requires memsetting a
fairly large array. This updates it to use cogl_pipeline_foreach_layer()
and we now derive an override_material to handle changes to the wrap
modes instead of using the CoglPipelineWrapModeOverrides.
Previously there was a check to avoid filling the path if there are
zero nodes. However the tesselator also won't generate any triangles
if there are less than 3 nodes so we might as well bail out in that
case too. If we don't emit any triangles then we would end up trying
to create an empty VBO. Although I don't think this should necessarily
be a problem, this seems to cause Mesa to segfault in version 7.8.1
when calling glBufferSubData (although not in
master). test-cogl-primitives tries to fill a path with only two
points so it's convenient to be able to avoid the crash in this case.
When adding a new entry to the journal a reference is now taken on the
current clip stack. Modifying the current clip state no longer causes
a journal flush. The journal flushing code now has an extra stage to
compare the clip state of each entry. The comparison can simply be
done by comparing the pointers. Although different clip states will
still end up with multiple draw calls this at leasts allows a scene
comprising of multiple different clips to be upload with one vbo. It
also lays the groundwork to do certain tricks when drawing clipped
rectangles such as modifying the geometry instead of setting a clip
state.
This adds a flag to avoid flushing the clip state when flushing the
framebuffer state. This will be used by the journal to manage its own
clip state flushing.
Flushing the clip state no longer does anything that would cause the
journal to flush. The clip state is only flushed when flushing the
framebuffer state and in all cases this ends up flushing the journal
in one way or another anyway. Avoiding flushing the journal will make
it easier to log the clip state in the journal.
Previously when trying to set up a rectangle clip that can't be
scissored or when using a path clip the code would use cogl_rectangle
as part of the process to fill the stencil buffer. This is now changed
to use a new internal _cogl_rectangle_immediate function which
directly uses the vertex array API to draw a triangle strip without
affecting the journal. This should be just as efficient as the
previous journalled code because these places would end up flushing
the journal immediately before and after submitting the single
rectangle anyway and flushing the journal always creates a new vbo so
it would effectively do the same thing.
Similarly there is also a new internal _cogl_clear function that does
not flush the journal.
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.
Instead of using the CoglHandle type for material variables this updates
the pango code to use CoglMaterial * instead. CoglHandle is the old
typename which is being phased out of the API.
The pango-display-list code was calling cogl_set_source in numerous
places and it didn't appear to be saving the users source to restore
later. This could result in the user inadvertantly drawing a primitive
with one of these internally managed materials instead of one that they
chose. To rectify this the code now uses cogl_{push,pop}_source to save
and restore the users source.
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.
