Commit Graph

13 Commits

Author SHA1 Message Date
Neil Roberts
cb178b7a3a Always add the #version pragma to shaders
Previously we would only add the #version pragma to shaders when
point sprite texture coordinates are enabled for a layer so that we
can access the gl_PointCoord builtin. However I don't think there's
any good reason not to just always request GLSL version 1.2 if it's
available. That way applications can always use gl_PointCoord without
having to enable point sprite texture coordinates.

This adds a glsl_version_to_use member to CoglContext which is used to
generate the #version pragma as part of the shader boilerplate. On
desktop GL this is set to 120 if version 1.2 is available, otherwise
it is left at 110. On GLES it is always left as 100.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
(cherry picked from commit e4dfe8b07e8af111ecbcb0da20ff2a2875a2b5d0)

Conflicts:
	cogl/driver/gl/gl/cogl-driver-gl.c
2013-09-02 16:22:01 +01:00
Neil Roberts
2933423ca7 Don't generate GLSL for the point size for default pipelines
Previously on GLES2 where there is no builtin point size uniform then
we would always add a line to the vertex shader to write to the
builtin point size output because when generating the shader it is not
possible to determine if the pipeline will be used to draw points or
not. This patch changes it so that the default point size is 0.0f
which is documented to have undefined results when drawing points.
That way we can avoid adding the point size code to the shader in that
case. The assumption is that any application that is drawing points
will probably have explicitly set the point size on the pipeline
anyway so it is not a big deal to change the default size from 1.0f.

This adds a new pipeline state flag to track whether the point size is
non-zero. This needs to be its own state because altering it needs to
cause a different shader to be added to the pipeline cache. The state
flags that affect the vertex shader have been changed from a constant
to a runtime function because they will be different depending on
whether there is a builtin point size uniform.

There is also a unit test to ensure that changing the point size does
or doesn't generate a new shader depending on the values.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit b2eba06e16b587acbf5c57944a70ceccecb4f175)

Conflicts:
	cogl/cogl-pipeline-private.h
	cogl/cogl-pipeline-state-private.h
	cogl/cogl-pipeline-state.c
	cogl/cogl-pipeline.c
2013-06-21 14:18:37 +01:00
Neil Roberts
6d51a18e7c Add support for per-vertex point sizes
This adds a new function to enable per-vertex point size on a
pipeline. This can be set with
cogl_pipeline_set_per_vertex_point_size(). Once enabled the point size
can be set either by drawing with an attribute named
'cogl_point_size_in' or by writing to the 'cogl_point_size_out'
builtin from a snippet.

There is a feature flag which must be checked for before using
per-vertex point sizes. This will only be set on GL >= 2.0 or on GLES
2.0. GL will only let you set a per-vertex point size from GLSL by
writing to gl_PointSize. This is only available in GL2 and not in the
older GLSL extensions.

The per-vertex point size has its own pipeline state flag so that it
can be part of the state that affects vertex shader generation.

Having to enable the per vertex point size with a separate function is
a bit awkward. Ideally it would work like the color attribute where
you can just set it for every vertex in your primitive with
cogl_pipeline_set_color or set it per-vertex by just using the
attribute. This is harder to get working with the point size because
we need to generate a different vertex shader depending on what
attributes are bound. I think if we wanted to make this work
transparently we would still want to internally have a pipeline
property describing whether the shader was generated with per-vertex
support so that it would work with the shader cache correctly.
Potentially we could make the per-vertex property internal and
automatically make a weak pipeline whenever the attribute is bound.
However we would then also need to automatically detect when an
application is writing to cogl_point_size_out from a snippet.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit 8495d9c1c15ce389885a9356d965eabd97758115)

Conflicts:
	cogl/cogl-context.c
	cogl/cogl-pipeline-private.h
	cogl/cogl-pipeline.c
	cogl/cogl-private.h
	cogl/driver/gl/cogl-pipeline-progend-fixed.c
	cogl/driver/gl/gl/cogl-pipeline-progend-fixed-arbfp.c
2013-06-07 16:53:29 +01:00
Neil Roberts
a131b697d9 Add the layer's sampler and uniform declarations at the start
Previously the sampler uniform declarations such as cogl_sampler0 were
generated by walking the list of layers in the shader state. This had
two problems. Firstly it would only generate the declarations for
layers that have been referenced. If a layer has a combine mode of
replace then the samplers from previous layers couldn't be used by
custom snippets. Secondly it meant that the samplers couldn't be
referenced by functions in the declarations sections because the
samplers are declared too late.

This patch fixes it to generate the layer declarations in the backend
start function using all of the layers on the pipeline instead. In
addition it adds the sampler declarations to the vertex shader as they
were previously missing.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit 1824df902bbb9995cae6ffb7a413913f2df35eef)

Conflicts:
	cogl/driver/gl/cogl-pipeline-fragend-glsl.c
	cogl/driver/gl/cogl-pipeline-vertend-glsl.c
2013-02-27 15:53:43 +00:00
Neil Roberts
956d39ac30 Add fragment and vertex snippet hooks for global declarations
This adds hook points to add global function and variable declarations
to either the fragment or vertex shader. The declarations can then be
used by subsequent snippets. Only the ‘declarations’ string of the
snippet is used and the code is directly put in the global scope near
the top of the shader.

The reason this is necessary rather than just adding a normal snippet
with the declarations is that for the other hooks Cogl assumes that
the snippets are independent of each other. That means if a snippet
has a replace string then it will assume that it doesn't even need to
generate the code for earlier hooks which means the global
declarations would be lost.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit ebb82d5b0bc30487b7101dc66b769160b40f92ca)
2013-02-27 14:43:55 +00:00
Robert Bragg
36c85da3b8 Remove cogl-internal.h
This remove cogl-internal.h in favour of using cogl-private.h. Some
things in cogl-internal.h were moved to driver/gl/cogl-util-gl-private.h
and the _cogl_gl_error_to_string function whose prototype was moved from
cogl-internal.h to cogl-util-gl-private.h has had its implementation
moved from cogl.c to cogl-util-gl.c

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit 01cc82ece091aa3bec4c07fdd6bc9e5135fca573)
2013-01-22 17:48:17 +00:00
Robert Bragg
7fa04bb1a6 Adds back tex_coord array for CoglShader compatibility
This adds back compatibility for CoglShaders that reference the
cogl_tex_coord_in[] or cogl_tex_coord_out[] varyings. Unlike the
previous way this was done this patch maintains the use of layer numbers
for attributes and maintains forwards compatibility by letting shaders
alternatively access the per-layer tex_coord varyings via
cogl_tex_coord%i_in/out defines that index into the array.
2013-01-22 17:48:07 +00:00
Robert Bragg
1c449c67f6 Remove the varying array for tex_coords
This removes the need to maintain an array of tex_coord varyings and
instead we now just emit a varying per-layer uniquely named using a
layer_number infix like cogl_tex_coord0_out and cogl_tex_coord0_in.

Notable this patch also had to change the journal flushing code to use
pipeline layer numbers to determine the name of texture coordinate
attributes.

We now also break batches by using a deeper comparison of layers so
such that two pipelines with the same number of layers can now cause a
batch break if they use different layer numbers.

This adds an internal _cogl_pipeline_layer_numbers_equal() function that
takes two pipelines and returns TRUE if they have the same number of
layers and all the layer numbers are the same too, otherwise it returns
FALSE.

Where we used to break batches based on changes to the number of layers
we now break according to the status of
_cogl_pipeline_layer_numbers_equal

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit e55b64a9cdc93285049d9b969bef67484c2d9fb3)

Note: this will cause a temporary regression for the Cogl 1.x CoglShader
api since it will break compatibility with existing shaders that
reference the texture varyings from the fragment shader.

The intention is to follow up with another patch to add back
CoglShader compatibility.
2013-01-22 17:48:06 +00:00
Neil Roberts
2616ae0fa9 Add a GL 3 driver
This adds a new CoglDriver for GL 3 called COGL_DRIVER_GL3. When
requested, the GLX, EGL and SDL2 winsyss will set the necessary
attributes to request a forward-compatible core profile 3.1 context.
That means it will have no deprecated features.

To simplify the explosion of checks for specific combinations of
context->driver, many of these conditionals have now been replaced
with private feature flags that are checked instead. The GL and GLES
drivers now initialise these private feature flags depending on which
driver is used.

The fixed function backends now explicitly check whether the fixed
function private feature is available which means the GL3 driver will
fall back to always using the GLSL progend. Since Rob's latest patches
the GLSL progend no longer uses any fixed function API anyway so it
should just work.

The driver is currently lower priority than COGL_DRIVER_GL so it will
not be used unless it is specificly requested. We may want to change
this priority at some point because apparently Mesa can make some
memory savings if a core profile context is used.

In GL 3, getting the combined extensions string with glGetString is
deprecated so this patch changes it to use glGetStringi to build up an
array of extensions instead. _cogl_context_get_gl_extensions now
returns this array instead of trying to return a const string. The
caller is expected to free the array.

Some issues with this patch:

• GL 3 does not support GL_ALPHA format textures. We should probably
  make this a feature flag or something. Cogl uses this to render text
  which currently just throws a GL error and breaks so it's pretty
  important to do something about this before considering the GL3
  driver to be stable.

• GL 3 doesn't support client side vertex buffers. This probably
  doesn't matter because CoglBuffer won't normally use malloc'd
  buffers if VBOs are available, but it might but worth making
  malloc'd buffers a private feature and forcing it not to use them.

• GL 3 doesn't support the default vertex array object. This patch
  just makes it create and bind a single non-default vertex array
  object which gets used just like the normal default object. Ideally
  it would be good to use vertex array objects properly and attach
  them to a CoglPrimitive to cache the state.

Reviewed-by: Robert Bragg <robert@linux.intel.com>

(cherry picked from commit 66c9db993595b3a22e63f4c201ea468bc9b88cb6)
2013-01-22 17:48:01 +00:00
Robert Bragg
01937201e4 Unify a lot of gles2 vs gl glsl code
Since we used to support hybrid fixed-function + glsl pipelines when
running with OpenGL there were numerous differences in how we handled
codegen and uniform updates between GLES2 and full OpenGL. Now that we
only support end-to-end glsl pipelines this patch can largely unify how
we handle GLES2 and OpenGL.

Most notably we now never use the builtin attribute names. This should
also make it easy for us to support creating strict OpenGL 3.1 contexts
where the builtin names have been removed.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit 2701b93f159bf2d3387cedf2d06fe921ad5641f3)
2013-01-22 17:48:01 +00:00
Robert Bragg
62b472f4f5 add cogl-glsl-shader files to aid backporting patches
To aid with backporting patches from master made after the deprecated
CoglShader api was removed this patch adds the cogl-glsl- files that
have been added on master so we should get less conflicts when cherry
picking.
2013-01-22 17:48:01 +00:00
Robert Bragg
8f3380adc3 Clearly define 3 progends that own the frag+vertends
This adds a new "fixed-arbfp" progend so we now have 3 distinct ways of
setting up the state of a pipeline:

  » fixed; where the vertex and fragment processing are implemented
    using fixed function opengl apis.
  » fixed-arbfp; where vertex processing is implemented using fixed
    function opengl apis but fragment processing is implemented
    using the ARB Fragment Processing language.
  » glsl; there vertex and fragment processing are both implemented
    using glsl.

This means we avoid unusual, combinations such as glsl for vertex
processing and arbfp for fragment processing, and also avoid pairing
fixed-function vertex processing with glsl fragment processing which we
happen to know hits some awkward code paths in Mesa that lead to poor
performance.

As part of this change, the progend now implies specific vertend and
fragend choices so instead of associating a vertend and fragend with a
pipeline we now just associate a progend choice.

When flushing a pipeline and choosing what progend to use, we now call a
progend->start() method that is able to determine if the vertend and
fragend together will be able to handle the given pipeline so the
vertend and fragend ->start() methods no longer need to return a boolean
status.

Since we now don't need to support glsl used in conjunction with fixed
function this will allow us to avoid ever using OpenGL builtin attribute
names, though this patch doesn't change that yet.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit cec381f50c7a2f2186bd4a8c5f38fecd5f099075)
2013-01-22 17:48:00 +00:00
Robert Bragg
5d62185f1c Re-organize the source layout
As part of an effort towards being able to write non-opengl based
backends for Cogl this moves most of the opengl specific code under
drivers/gl. drivers/gl and drivers/gles have been moved to
drivers/gl/gl and drivers/gl/es respectively.

Reviewed-by: Neil Roberts <neil@linux.intel.com>

(cherry picked from commit 7dc482facb0a265c7f48660079e7e12dd7a2813e)
2013-01-22 17:47:19 +00:00