For some operations on pre-multiplied colors (say, replace the alpha
value), you need to unpremultiply the color.
This patch provides the counterpart to cogl_color_premultiply().
The place where we actually change the framebuffer is
_cogl_framebuffer_flush_state(), so if we changed to a new frame buffer
we need to initialize the color bits there.
http://bugzilla.openedhand.com/show_bug.cgi?id=2094
OpenGL 3.0 deprecated querying of the GL_{RED,GREEN,BLUE}_BITS
constants, and the FBO extension provides a mechanism to query for the
color buffer sizes which *should* work even with the default
framebuffer. Unfortunately, this doesn't seem to hold for Mesa - so we
just use this for the offscreen CoglFramebuffer type, and we fall back
to glGetIntegerv() for the onscreen one.
http://bugzilla.openedhand.com/show_bug.cgi?id=2094
This function had two problems. Firstly it would clear the enable
blend flag before calling pre_change_notify so that if blending was
previously enabled the journal would end up being flushed while the
flag was still cleared. Secondly it would call the pre change notify
whenever blending is needed regardless of whether it was already
needed previously.
This was causing problems in test-depth.
This adds a _cogl_bind_gl_texture_transient function that should be used
instead of glBindTexture so we can have a consistent cache of the
textures bound to each texture unit so we can avoid some redundant
binding.
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
_cogl_atlas_texture_blit_begin binds a texture to use as the
destination and it expects it to stay bound until
_cogl_atlas_texture_end_blit is called. However there was a call to
_cogl_journal_flush directly after setting up the blit state which
could cause the wrong texture to be bound. This just moves the flush
to before the call to _cogl_atlas_texture_blit_begin.
This was breaking test-cogl-sub-texture.
1) Always flush when migrating textures out of an atlas because although
it's true that the original texture data will remain valid in the
original texture we can't assume that journal entries have resolved the
GL texture that will be used. This is only true if a layer0_override has
been used.
2) Don't flush at the point of creating a new atlas simply flush
immediately before reorganizing an atlas. This means we are now assuming
that we will never see recursion due to atlas textures being modified
during a journal flush. This means it's the responsibility of the
primitives code to _ensure_mipmaps for example not the responsibility of
_cogl_material_flush_gl_state.
We want to make sure that the material state flushing code will never
result in changes to the texture storage for that material. So for
example mipmaps need to be ensured by the primitives code.
Changes to the texture storage will invalidate the texture coordinates
in the journal and we want to avoid a recursion of journal flushing.
This adds a way to compare two CoglMatrix structures to see if they
represent the same transformations. memcmp can't be used because a
CoglMatrix contains private flags and padding.
THIS IS A WORK IN PROGRESS
Mesa is building a big shader when using ARB_texture_env_combine. The
idea is to bypass that computation, do it ourselves and cache the
compiled program in a CoglMaterial.
For now that feature can be enabled by setting the COGL_PIPELINE
environment variable to "arbfp". COGL_SHOW_FP_SOURCE can be set to a non
empty string to dump the fragment program source too.
TODO:
* fog (really easy, using OPTION)
* support tex env combiner operands, DOT3, ADD_SIGNED, INTERPOLATE
combine modes (need refactoring the generation of temporary
variables) (not too hard)
* alpha testing for GLES 2.0?
The Cogl context has now a feature_flags_private enum that will allow us
to query and use OpenGL features without exposing them in the public
API.
The ARB_fragment_program extension is the first user of those flags.
Looking for this extension only happens in the gl driver as the gles
drivers will not expose them.
One can use _cogl_features_available_private() to check for the
availability of such private features.
While at it, reindent cogl-internal.h as described in CODING_STYLE.
At two places in cogl_wrap_prepare_for_draw it was trying to loop over
the texture units to flush some state. However it was retrieving the
texture unit pointer using w->active_texture_unit instead of the loop
index so it would end up with the wrong state.
Also in glEnableClientState it was using the active unit instead of
the client active unit.
• 3 general fixes (typos, copy/paste),
• ignore cogl-object-private.h,
• cogl_fixed_atani() was in reality cogl_fixed_atan(), fixed in commit
43564f05.
• Fix the cogl-vector section: sections must have a </SECTION> tag at
the end. Also the cogl-vector section was added in the middle of the
cogl-buffer one. Let's shiffle it out and add that </SECTION> tag.
As with a351ff2af earlier, distributing headers generated at configure
time conflicts with out of tree builds as the distributed headers will
be included first instead of including the generated ones.
This provides a mechanism for associating private data with any
CoglObject. We expect Clutter will use this to associate weak materials
with normal materials.
This replaces the use of CoglHandle with strongly type CoglClipStack *
pointers instead. The only function not converted for now is
cogl_is_clip_stack which will be done in a later commit.
This replaces the use of CoglHandle with strongly type CoglBitmap *
pointers instead. The only function not converted for now is
cogl_is_bitmap which will be done in a later commit.
This replaces the use of CoglHandle with strongly type CoglPath *
pointers instead. The only function not converted for now is
cogl_is_path which will be done in a later commit.
This patch makes it so that only the backwards compatibility
COGL_HANDLE_DEFINE macro defines a _cogl_xyz_handle_new function. The
new COGL_OBJECT_DEFINE macro only defines a _cogl_xyz_object_new
function.
It's valid C to declare a function omitting it prototype, but it seems
to be a good practise to always declare a function with its
corresponding prototype.
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.
CoglHandle is a common source of complaints and confusion because people
expect a "handle" to be some form of integer type with some indirection
to lookup the corresponding objects as opposed to a direct pointer.
This patch starts by renaming CoglHandle to CoglObject * and creating
corresponding cogl_object_ APIs to replace the cogl_handle ones.
The next step though is to remove all use of CoglHandle in the Cogl APIs
and replace with strongly typed pointer types such as CoglMaterial * or
CoglTexture * etc also all occurrences of COGL_INVALID_HANDLE can just
use NULL instead.
After this we will consider switching to GTypeInstance internally so we
can have inheritance for our types and hopefully improve how we handle
bindings.
Note all these changes will be done in a way that maintains the API and
ABI.
Since the default alpha test function of GL_ALWAYS is equivalent to
GL_ALPHA_TEST being disabled we don't need to worry about Enabling/Disabling
it when flushing material state, instead it's enough to leave it always
enabled. We will assume that any driver worth its salt wont incur any
additional cost for glEnable (GL_ALPHA_TEST) + GL_ALWAYS vs
glDisable (GL_ALPHA_TEST).
This patch simply calls glEnable (GL_ALPHA_TEST) in cogl_create_context
When _cogl_disable_other_texcoord_arrays is called it disables the
neccessary texcoord arrays and then removes the bits for the disabled
arrays in ctx->texcoord_arrays_enabled. However none of the places
that call the function then set any bits in ctx->texcoord_arrays_enabled
so the arrays would never get marked and they would never get disabled
again.
This patch just changes it so that _cogl_disable_other_texcoord_arrays
also sets the corresponding bits in ctx->texcoord_arrays_enabled.
Instead of directly using a guint32 to store a bitmask for each used
texcoord array, it now stores them in a CoglBitmask. This removes the
limitation of 32 layers (although there are still other places in Cogl
that imply this restriction). To disable texcoord arrays code should
call _cogl_disable_other_texcoord_arrays which takes a bitmask of
texcoord arrays that should not be disabled. There are two extra
bitmasks stored in the CoglContext which are used temporarily for this
function to avoid allocating a new bitmask each time.
http://bugzilla.openedhand.com/show_bug.cgi?id=2132
This implements a growable array of bits called CoglBitmask. The
CoglBitmask is intended to be cheap if less than 32 bits are used. If
more bits are required it will allocate a GArray. The type is meant to
be allocated on the stack but because it can require additional
resources it also has a destroy function.
http://bugzilla.openedhand.com/show_bug.cgi?id=2132
Previously the counter for the number of layers was only updated
whenever the texture handle for a layer changes. However there are
many other ways for a new layer to be created for example by setting a
layer combine constant. Also by default the texture on a layer is
COGL_INVALID_HANDLE so if the application tries to create an explicit
layer with no texture by calling cogl_material_set_layer with
COGL_INVALID_HANDLE then it also wouldn't update the count.
This patch fixes that by incrementing the count in
cogl_material_get_layer instead. This function is called by all
functions that may end up creating a layer so it seems like the most
appropriate place.
http://bugzilla.openedhand.com/show_bug.cgi?id=2132
It should be quite acceptable to use a texture without defining any
texture coords. For example a shader may be in use that is doing
texture lookups without referencing the texture coordinates. Also it
should be possible to replace the vertex colors using a texture layer
without a texture but with a constant layer color.
enable_state_for_drawing_buffer no longer sets any disabled layers in
the overrides. Instead of counting the number of units with texture
coordinates it now keeps them in a mask. This means there can now be
gaps in the list of enabled texture coordinate arrays. To cope with
this, the Cogl context now also stores a mask to track the enabled
arrays. Instead of code manually iterating each enabled array to
disable them, there is now an internal function called
_cogl_disable_texcoord_arrays which disables a given mask.
I think this could also fix potential bugs when a vertex buffer has
gaps in the texture coordinate attributes that it provides. For
example if the vertex buffer only had texture coordinates for layer 2
then the disabling code would not disable the coordinates for layers 0
and 1 even though they are not used. This could cause a crash if the
previous data for those arrays is no longer valid.
http://bugzilla.openedhand.com/show_bug.cgi?id=2132
This adds a math utility API for handling 3 component, single precision
float vectors with the following; mostly self explanatory functions:
cogl_vector3_init
cogl_vector3_init_zero
cogl_vector3_equal
cogl_vector3_equal_with_epsilon
cogl_vector3_copy
cogl_vector3_free
cogl_vector3_invert
cogl_vector3_add
cogl_vector3_subtract
cogl_vector3_multiply_scalar
cogl_vector3_divide_scalar
cogl_vector3_normalize
cogl_vector3_magnitude
cogl_vector3_cross_product
cogl_vector3_dot_product
cogl_vector3_distance
Since the API is experimental you will need to define
COGL_ENABLE_EXPERIMENTAL_API before including cogl.h if you want to use
the API.
This stubs out an xlib event handling mechanism for Cogl. The intention
is for Clutter to use this to forward all x11 events to Cogl. As we move
winsys functionality down into Cogl, Cogl will become responsible for
handling a number of X events: ConfigureNotify events for onscreen
framebuffers, swap events and Damage events for cogl_x11_texture_pixmap.
Previously it would only try to set the blend equation if the RGB and
alpha blending functions were different. However it's completely valid
to use a non-standard blending function when the functions are the
same. This patch moves the blending equation to outside the if
statement.
Previously it would only set the blend constant if glBlendFuncSeparate
was used but it is perfectly acceptable to use the blend constant when
the same factor is used for each. It now sets the blend constant
whenever one of the factors would use the constant.
When a single statement is used to specify the factors for both the
RGB and alpha parts it previously split up the statement into
two. This works but it ends up unnecessarily using glBlendFuncSeparate
when glBlendFunc would suffice.
For example, the blend statement
RGBA = ADD(SRC_COLOR*(SRC_COLOR), DST_COLOR*(1-SRC_COLOR))
would get split into the two statements
RGBA = ADD(SRC_COLOR*(SRC_COLOR[RGB]), DST_COLOR*(1-SRC_COLOR[RGB]))
A = ADD(SRC_COLOR*(SRC_COLOR[A]), DST_COLOR*(1-SRC_COLOR[A]))
That translates to:
glBlendFuncSeparate (GL_SRC_COLOR, GL_ONE_MINUS_SRC_COLOR,
GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
This patch makes it so that arg_to_gl_blend_factor can handle the
combined RGBA mask instead. That way the single statement gets
translated to the equivalent call:
glBlendFunc (GL_SRC_COLOR, GL_ONE_MINUS_SRC_COLOR);
