Previously when comparing whether the settings for a layer are equal
it would only check if one of them was enabled. If so then it would
assume the other one was enabled and continue to compare the texture
environment. Now it also checks whether the enabledness differs.
This adds a COGL_OBJECT_INTERNAL_DEFINE macro and friends that are the
same as COGL_OBJECT_DEFINE except that they prefix the cogl_is_*
function with an underscore so that it doesn't get exported in the
shared library.
Previously COGL_OBJECT_DEFINE would always define deprecated
cogl_$type_{ref,unref} functions even if the type is new or if the
type is entirely internal. An application would still find it
difficult to use these because they wouldn't be in the headers, but it
still looks bad that they are exported from the shared library. This
patch changes it so that the deprecated ref counting functions are
defined using a separate macro and only the types that have these
functions in the headers call this macro.
Since 365605cf42, materials and layers are represented in a tree
structure that allows traversing up through parents and iterating down
through children. This re-works the related typedefs and reparenting
code so that they can be shared.
Under big GL, _cogl_texture_driver_size_supported uses the proxy
texture to check whether the given texture size is supported. Proxy
textures aren't available under GLES so previously this would just
return TRUE to assume all texture sizes are supported. This patch
makes it use glGetIntegerv with GL_MAX_TEXTURE_SIZE to give a second
best guess.
This fixes the sliced texture backend so that it will use slices when
the texture is too big.
When an intermediate buffer is used for downloading texture data it
was using the wrong byte length for a row so the copy back to the
user's buffer would fail.
The fallback for when glGetTexImage is not available renders the
texture to the framebuffer to read the data using glReadPixels. This
patch just sets the COGL_MATERIAL_FILTER_NEAREST filter mode on the
material before rendering to avoid linear filtering which would alter
the texture data.
The fallback for when glGetTexImage is not available draws parts of
the texture to the framebuffer and uses glReadPixels to extract the
data. However it was using cogl_rectangle to draw and then immediately
using raw glReadPixels to fetch the data. This won't cause a journal
flush so the rectangle won't necessarily have hit the framebuffer
yet. Instead it now uses cogl_read_pixels which does flush the
journal.
There were a few problems flushing texture overrides so that sliced
textures would not work:
* In _cogl_material_set_layer_texture it ignored the 'overriden'
parameter and always set texture_overridden to FALSE.
* cogl_texture_get_gl_texture wasn't being called correctly in
override_layer_texture_cb. It returns a gboolean to indicate the
error status but this boolean was being assigned to gl_target.
* _cogl_material_layer_texture_equal did not take into account the
override.
* _cogl_material_layer_get_texture_info did not return the overridden
texture so it would always use the first texture slice.
There was a lot of common code that was copied to all of the backends
to convert the data to a suitable format and wrap it into a CoglBitmap
so that it can be passed to _cogl_texture_driver_upload_subregion_to_gl.
This patch moves the common code to cogl-texture.c so that the virtual
just takes a CoglBitmap that is already in the right format.
Previously cogl_texture_get_data would pretty much directly pass on to
the get_data texture virtual function. This ended up with a lot of
common code that was copied to all of the backends. For example, the
method is expected to return the required data size if the data
pointer is NULL and to calculate its own rowstride if the rowstride is
0. Also it needs to convert the downloaded data if GL can't support
that format directly.
This patch moves the common code to cogl-texture.c so the virtual is
always called with a format that can be downloaded directly by GL and
with a valid rowstride. If the download fails then the virtual can
return FALSE in which case cogl-texture will use the draw and read
fallback.
For point sprites you are usually drawing the whole texture so you
most often want GL_CLAMP_TO_EDGE. This patch removes the override for
COGL_MATERIAL_WRAP_MODE_AUTOMATIC when point sprites are enabled for a
layer so that it will clamp to edge.
This adds a new API call to enable point sprite coordinate generation
for a material layer:
void
cogl_material_set_layer_point_sprite_coords_enabled (CoglHandle material,
int layer_index,
gboolean enable);
There is also a corresponding get function.
Enabling point sprite coords simply sets the GL_COORD_REPLACE of the
GL_POINT_SPRITE glTexEnv when flusing the material. There is no
separate application control for glEnable(GL_POINT_SPRITE). Instead it
is left permanently enabled under the assumption that it has no affect
unless GL_COORD_REPLACE is enabled for a texture unit.
http://bugzilla.openedhand.com/show_bug.cgi?id=2047
Recently I added a _cogl_debug_dump_materials_dot_file function for
debugging the sparse material state. This extends the state dumped to
include the graph of layer state also.
We were mistakenly only initializing layer->layer_index for new layers
associated with texture units > 0. This had gone unnoticed because
normally layers associated with texture unit0 have a layer index of 0
too. Mutter was hitting this issue because it was initializing layer 1
before layer 0 for one of its materials so layer 1 was temporarily
associated with texture unit 0.
* cally-merge:
cally: Add introspection generation
cally: Improving cally doc
cally: Cleaning CallyText
cally: Refactoring "window:create" and "window:destroy" emission code
cally: Use proper backend information on CallyActor
cally: Check HAVE_CONFIG_H on cally-util.c
docs: Fix Cally documentation
cally: Clean up the headers
Add binaries of the Cally examples to the ignore file
docs: Add Cally API reference
Avoid to load cally module on a11y examples
Add accessibility tests
Initialize accessibility support on clutter_init
Rename some methods and includes to avoid -Wshadow warnings
Cally initialization code
Add Cally
Toolkits and applications not written in C might still need access to
the Cally API to write accessibility extensions based on it for their
own native elements.
Previously cogl_set_fog would cause a flush of the Cogl journal and
would directly bang the GL state machine to setup fogging. As part of
the ongoing effort to track most state in CoglMaterial to support
renderlists this now adds an indirection so that cogl_set_fog now just
updates ctx->legacy_fog_state. The fogging state then gets enabled as a
legacy override similar to how the old depth testing API is handled.
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 adds three new feature flags COGL_FEATURE_TEXTURE_NPOT_BASIC,
COGL_FEATURE_TEXTURE_NPOT_MIPMAP and COGL_FEATURE_TEXTURE_NPOT_REPEAT
that can tell you if your hardware supports non power of two textures,
npot textures + mipmaps and npot textures + wrap modes other than
CLAMP_TO_EDGE.
The pre-existing COGL_FEATURE_TEXTURE_NPOT feature implies all of the
above.
By default GLES 2 core supports npot textures but mipmaps and repeat
modes can only be used with power of two textures. This patch also makes
GLES check for the GL_OES_texture_npot extension to determine if mipmaps
and repeating are supported with npot textures.
glDisableVertexAttribArray was defined to glEnableVertexAttribArray so
it would probably cause crashes if it was ever used. Presumably
nothing is using these yet because the generic attributes are not yet
tied to shader attributes in a predictable way.
For testing purposes, either to identify bugs in Cogl or the driver or
simulate lack of PBO support COGL_DEBUG=disable-pbos can be used to
fallback to malloc instead.
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.
This changes the cogl_is_XYZ function prototypes generated when using
the COGL_OBJECT_DEFINE macro to take a void * argument instead of a
CoglHandle argument.
This removes cogl_pixel_array_new which just took a size in bytes.
Without the image size and pixel format then the driver often doesn't
have enough information to allocate optimal GPU memory that can be
textured from directly. This is because GPUs often have ways to
spatially alter the layout of a texture to improve cache access patterns
which may require special alignment and padding dependant in the images
width, height and bpp.
Although currently we are limited by OpenGL because it doesn't let us
pass on the width and height when allocating a PBO, the hope is that we
can define a better extension at some point.
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.
This adds a _cogl_debug_dump_materials_dot_file function that can be
used to dump all the descendants of the default material to a file using
the dot format which can then be converted to an image to visualize.
In _cogl_material_pre_change_notify if a material with descendants is
modified then we create a new material that is a copy of the one being
modified and reparent those descendants to the new material.
This patch ensures we drop the reference we get from cogl_material_copy
since we can rely on the descendants to keep the new material alive.
The commit to split the fragment processing backends out from
cogl-material.c (3e1323a636) broke the GLES 1 and 2 builds the
fix was to guard the code in each backend according to the
COGL_MATERIAL_BACKEND_XYZ defines which are setup in
cogl-material-private.h.
The documentation for cogl_vertex_buffer_indices_get_for_quads was
using ugly ASCII art to draw the diagrams. These have now been
replaced with PNG figures.
CoglMaterialWrapMode was missing from the cogl-sections.txt file so it
wasn't getting displayed. There were also no documented return values
from the getters.
The tesselator code uses some defines that it expects to be in the GL
headers such as GLAPI and GLAPIENTRY. These are used to mark the entry
points as exportable on each platform. We don't really want the
tesselator code to use these but we also don't want to modify the C
files so instead they are #defined to be empty in the stub glu.h. That
header is only included internally when building the tesselator/ files
so it shouldn't affect the rest of Cogl.
GLES also doesn't have a GLdouble type so we just #define this to be a
regular double.
cogl_material_copy was taking a reference on the original texture when
making a copy. However it then calls _cogl_material_set_parent on the
material which also takes a reference on the parent. The second
reference is cleaned up whenever _cogl_material_unparent is called and
this is also called by _cogl_material_free. However, it seems that
nothing was cleaning up the first reference. I think the reference is
entirely unnecessary so this patch removes it.
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.
This grabs the latest code for libtess from git Mesa. This is mostly
so that we can get the following commit which fixes a lot of compiler
warnings in Clutter:
commit 75acb896c6da758d03e86f8725d6ca0cb2c6ad82
Author: Neil Roberts <neil@linux.intel.com>
Date: Wed Jun 30 12:41:11 2010 +0100
glu: Fix some compiler warnings in libtess
When compiled with the more aggressive compiler warnings such as
-Wshadow and -Wempty-body the libtess code gives a lot more
warnings. This fixes the following issues:
* The 'Swap' macro tries to combine multiple statements into one and
then consume the trailing semicolon by using if(1){/*...*/}else.
This gives warnings because the else part ends up with an empty
statement. It also seems a bit dangerous because if the semicolon
were missed then it would still be valid syntax but it would just
ignore the following statement. This patch replaces it with the more
common idiom do { /*...*/ } while(0).
* 'free' was being used as a local variable name but this shadows the
global function. This has been renamed to 'free_handle'
* TRUE and FALSE were being unconditionally defined. Although this
isn't currently a problem it seems better to guard them with #ifndef
because it's quite common for them to be defined in other headers.
https://bugs.freedesktop.org/show_bug.cgi?id=28845
As part of the ongoing effort to remove CoglHandle from the API this
switches the cogl_material API to use a strongly typed CoglMaterial
pointer instead of CoglHandle.
This splits the fragment processing backends (glsl, arbfp and fixed) out
from cogl-material.c into their own cogl-material-{glsl,arbfp,fixed}.c
files in an effort to help and keep cogl-material.c maintainable.
This adds two new API calls- cogl_path_set_fill_rule and
cogl_path_get_fill_rule. This allows modifying the fill rule of the
current path. In addition to the previous default fill rule of
'even-odd' it now supports the 'non-zero' rule. The fill rule is a
property of the path (not the Cogl context) so creating a new path or
preserving a path with cogl_path_get_handle affects the fill rule.
The scanline path rasterizer has been removed because the paths can be
drawn with the tesselator instead. The option therefore no longer does
anything.
Instead of drawing paths using the stencil buffer trick, it now
tesselates the path into triangles using the GLU tesselator and
renders them directly. A vbo is created with one vertex for each node
on the path. The tesselator is used to generate a series of indices
into the vbo as triangles. The tesselator's output of strips and fans
is converted into GL_TRIANGLES so that it can be rendered with a
single draw call (but the vertices are still shared via the
indices). The vbo is stored with the path so that if the application
uses retained paths then Cogl won't have to tessellate again.
The vertices also have texture coordinates associated with them so
that it can replicate the old behaviour of drawing a material with a
texture by fitting the texture to the bounding box of the path and
then clipping it. However if the texture contains waste or is sliced
then the vertex buffer code will refuse to draw it. In this case it
will revert back to drawing the path into the stencil buffer and then
drawing the material as a clipped quad.
The VBO is used even when setting up the stencil buffer for clipping
to a path because the tessellated geometry may cover less area.
The old scanline rasterizer has been removed because the tesselator
should work equally well on drivers with no stencil buffer.
This copies the files for the GLU tesselator from Mesa. The Mesa code
is based on the original SGI code and is released under a BSD license.
The memalloc.h header has been replaced with one that forces the code
to use g_malloc and friends. The rest of the files are not altered
from the original so it should be possible to later upgrade the files
by simply overwriting them.
There is a tesselator.h header which is expected to be included by
rest of Cogl to use the tesselator. This contains a trimmed down
version of glu.h that only includes parts that pertain to the
tesselator. There is also a stub glu.h in the GL directory which is
just provided so that the tesselator code can include <GL/gl.h>
without depending on the system header. It just redirects to
tesselator.h
Some of the arguments to the material and path functions were taking a
pointer to a CoglColor or an array of floats that was not intended to
be written to but were not marked with const.
in _cogl_material_prune_empty_layer_difference we sometimes unref the
given layer before dereferencing it to get a pointer to its parent. This
defers the unref until after we have fetched the parent pointer.
Commit 7fae8ac051 changed cogl-defines.h.in so there is only a
single copy in clutter/cogl/ instead of one for each driver. However
the old files were still mentioned in the EXTRA_DIST of the
Makefile.am so make distcheck was failing.
A pedantic change to get_fbconfig_for_depth() so that we don't need to
make any assumptions about the GLXFBConfig typedef or what values
we can overload to indicate an invalid config.
get_fbconfig_for_depth() now simply returns FALSE if it fails to find a
config.
This is a publicly exposed texture backend to create a texture which
contains the contents of an X11 pixmap. The API is currently marked as
experimental.
The backend internally holds a handle to another texture. All of the
backend virtuals simply redirect to the internal texture.
The texture can optionally be automatically updated if the
automatic_updates parameter is TRUE. If set then Cogl will listen for
damage events on the pixmap and update the texture accordingly.
Alternatively a damage object can be created externally and passed
down to Cogl.
The updates can be performed with XGetImage, XShmGetImage or the
GLX_EXT_texture_pixmap extension. If the TFP extension is used it will
optionally try to create a rectangle texture if the driver does not
support NPOTs or it is forced through the
COGL_PIXMAP_TEXTURE_RECTANGLE or CLUTTER_PIXMAP_TEXTURE_RECTANGLE
environment variables.
If the GLXFBConfig does not support mipmapping then it will fallback
to using X{Shm,}GetImage. It keeps a separate texture around for this
so that it can later start using the TFP texture again if the texture
is later drawn with mipmaps disabled.
This will be defined in cogl-defines.h whenever Cogl is built using a
winsys that supports X11. This implies CoglTexturePixmapX11 will be
available.
To make this work the two separate cogl-defines.h.in files have been
merged into one. The configure script now makes a @COGL_DEFINES@
substitution variable which contains the #define lines to put in
rather than directly having them in the seperate files.
This is similar to clutter_x11_{,un}trap_errors except that it stores
the previous trap state in a caller-allocated struct so that it can be
re-entrant.
Make _cogl_xlib_trap_errors re-entrant
(this will be squashed into an earlier commit)
The _cogl_texture_needs_premult_conversion function was already
checking whether the source format had an alpha channel before
returning TRUE, but it also doesn't make sense to do the premult
conversion if the destination format has no alpha. This patch adds
that check in too.
This adds the framework needed to check for winsys specific extensions
(such as GLX extensions) using a similar mechanism to the
cogl-feature-functions header. There is a separate
cogl-winsys-feature-functions header which will contain macros to list
the extensions and functions. cogl_create_context_winsys now calls
_cogl_feature_check for each of these functions. _cogl_feature_check
has had to be changed to accept the driver prefix as the first
parameter so that it can prepend "GLX" rather than "GL" in this case.
The Clutter X11 backend now passes all events through
_cogl_xlib_handle_event. This function can now internally be hooked
with _cogl_xlib_add_filter. These are added to a list of callbacks
which are all called in turn by _cogl_xlib_handle_event. This is
intended to be used internally in Cogl by any parts that need to see
Xlib events.
Cogl now also has an internally exposed function to set a pointer to
the Xlib display. This is stored in a global variable. The Clutter X11
backend sets this.
_cogl_xlib_handle_event and _cogl_xlib_set_display can be removed once
Cogl gains a proper window system abstraction.
This creates a separate struct to store the fields of the context that
are specific to the winsys. This is all stored in one file but ideally
this could work more like the CoglContextDriver struct and have a
different header for each winsys.
This adds an internal rectangle texture backend which is mostly based
on the CoglTexture2D backend. It will throw assert failures if any
operations are attempted that rectangle textures don't support, such
as mipmapping or hardware repeating.
Instead of the ensure_mipmaps virtual that is only called whenever the
texture is about to be rendered with a min filter that needs the
mipmap, there is now a pre_paint virtual that is always called when
the texture is about to be painted in any way. It has a flags
parameter which is used to specify whether the mipmap will be needed.
This is useful for CoglTexturePixmapX11 because it needs to do stuff
before painting that is unrelated to mipmapping.
Instead of having a hardcoded series of if-statements in
cogl_is_texture to determine which types should appear as texture
subclasses, they are now stored in a GSList attached to the Cogl
context. The list is amended to using a new cogl_texture_register_type
function. There is a convenience macro called COGL_TEXTURE_DEFINE
which uses COGL_HANDLE_DEFINE_WITH_CODE to register the texture type
when the _get_type() function is first called.
This macro is similar to COGL_HANDLE_DEFINE_WITH_CODE except that it
allows a snippet of code to be inserted into the _get_type()
function. This is similar to how G_DEFINE_TYPE_WITH_CODE
works. COGL_HANDLE_DEFINE is now just a wrapper around
COGL_HANDLE_DEFINE_WITH_CODE.
_cogl_texture_2d_externally_modified is a function specific to the
CoglTexture2D texture backend that should be called whenever the
contents of the texture are modified without the backend knowing about
it. It simply marks the mipmap tree as invalid.
The include path for the winsys and driver folder was given relative
to $(srcdir) so it would end up relative to the driver folder which is
wrong. It is now specified as $(srcdir)/../../winsys to get the right
location. The driver folder is removed because it is actually just
$(srcdir) and that is already included.
GLES2 doesn't provide user clip planes (you would have to use a vertex +
fragment shader to achieve the same kind of result) so we make sure not
to call glEnable/Disable with any of the GL_CLIP_PLANE0..3 defines.
http://bugzilla.o-hand.com/show_bug.cgi?id=2177
The function had a line like:
CoglMaterial *material =
material = _cogl_material_pointer_from_handle (material_handle);
where the duplicate "material =" wasn't intended, so this patch removes
it.
Under WGL, any functions that were defined after GL 1.1 are not
directly exported in the DLL so we need to reference them via the
function pointers. A new call to glActiveUnit was missed in
cogl-context.c
The window headers contain the line
#define near
so it's not possible to use the symbol 'near' in code that's portable
to Windows. This replaces it with 'near_val'.
I think the define is meant to improve compatibility with code written
for Windows 3.1 where near would be a keyword to make it a smaller
pointer size.
We don't need to generate a new ARBfp program for every material created
if we can find an ancestor whos state will result in the same program
being generated.
The more code we can have adopt the coding pattern of deriving their
materials from other similar materials using cogl_material_copy() the
more likely this metric will be good enough on its own to minimize the
set of arbfp programs necessary to support a given application.
Previously in _cogl_material_pre_change_notify we manually freed the
layer caches of a material if we caused a reparent, but it makes more
sense to have _cogl_material_set_parent do this directly instead.
This adds a _cogl_material_weak_copy() function that can be used to
create materials that don't count as strong dependants on their parents.
This means the parent can be modified without worrying about how it will
affect weak materials. The material age of the parent can potentially be
queried to determine if a weak material might need to be re-created.
When we add support for weak materials it's expected that Clutter will
want to attach them as private data to other materials and it needs a
mechanism to determine when a weak material should be re-created because
its parent has changed somehow.
This adds the concept of a material age (internal only currently) which
increments whenever a material is modified. Clutter can then save the
age of the material which its weak materials are derived from and later
determine when the weak material may be invalid.
In _cogl_texture_quad_multiple_primitives we weren't memsetting the
CoglMaterialWrapModeOverrides structure we were memsetting
&state.wrap_mode_overrides where state.wrap_mode_overrides is just a
pointer that might potentially later point to the
CoglMaterialWrapModeOverrides structure.
In _cogl_material_equal we were repeating the same code pattern to
compare several of the state groups so this just adds
simple_property_equal function that's now used instead.
This redirects the legacy depth testing APIs through CoglMaterial and
adds a new experimental cogl_material_ API for handling the depth
testing state.
This adds the following new functions:
cogl_material_set_depth_test_enabled
cogl_material_get_depth_test_enabled
cogl_material_set_depth_writing_enabled
cogl_material_get_depth_writing_enabled
cogl_material_set_depth_test_function
cogl_material_get_depth_test_function
cogl_material_set_depth_range
cogl_material_get_depth_range
As with other experimental Cogl API you need to define
COGL_ENABLE_EXPERIMENTAL_API to access them and their stability isn't
yet guaranteed.
cogl_ortho is one of those APIs whos style was, for better or worse,
copied from OpenGL and for some inexplicable reason the near and far
arguments are inconsistent with the left, right, top, bottom arguments
because they don't take z coordinates they take a "distance" which
should be negative for a plane behind the viewer.
This updates the documentation to explain this.
The internal CoglMaterialLayer pointers associated with a material may
change whenever layer properties are modified so it's no longer ok to
assume that a list of layers returned by cogl_material_get_layers
remains valid if the layers have been changed.
Since it can sometimes be awkward to figure out where a particular
material came from when debugging, this adds a breadcrumb mechanism that
lets you associate a const string with a material that may give a clue
about its origin.
As a follow on to using cogl_material_copy instead of flush options this
patch now removes the ability to pass flush options to
_cogl_material_equal which is the final reference to the
CoglMaterialFlushOptions mechanism.
Since cogl_material_copy should now be cheap to use we can simplify
how we handle fallbacks and wrap mode overrides etc by simply copying
the original material and making our override changes on the new
material. This avoids the need for a sideband state structure that has
been growing in size and makes flushing material state more complex.
Note the plan is to eventually use weak materials for these override
materials and attach these as private data to the original materials so
we aren't making so many one-shot materials.
This is a complete overhaul of the data structures used to manage
CoglMaterial state.
We have these requirements that were aiming to meet:
(Note: the references to "renderlists" correspond to the effort to
support scenegraph level shuffling of Clutter actor primitives so we can
minimize GPU state changes)
Sparse State:
We wanted a design that allows sparse descriptions of state so it scales
well as we make CoglMaterial responsible for more and more state. It
needs to scale well in terms of memory usage and the cost of operations
we need to apply to materials such as comparing, copying and flushing
their state. I.e. we would rather have these things scale by the number
of real changes a material represents not by how much overall state
CoglMaterial becomes responsible for.
Cheap Copies:
As we add support for renderlists in Clutter we will need to be able to
get an immutable handle for a given material's current state so that we
can retain a record of a primitive with its associated material without
worrying that changes to the original material will invalidate that
record.
No more flush override options:
We want to get rid of the flush overrides mechanism we currently use to
deal with texture fallbacks, wrap mode changes and to handle the use of
highlevel CoglTextures that need to be resolved into lowlevel textures
before flushing the material state.
The flush options structure has been expanding in size and the structure
is logged with every journal entry so it is not an approach that scales
well at all. It also makes flushing material state that much more
complex.
Weak Materials:
Again for renderlists we need a way to create materials derived from
other materials but without the strict requirement that modifications to
the original material wont affect the derived ("weak") material. The
only requirement is that its possible to later check if the original
material has been changed.
A summary of the new design:
A CoglMaterial now basically represents a diff against its parent.
Each material has a single parent and a mask of state that it changes.
Each group of state (such as the blending state) has an "authority"
which is found by walking up from a given material through its ancestors
checking the difference mask until a match for that group is found.
There is only one root node to the graph of all materials, which is the
default material first created when Cogl is being initialized.
All the groups of state are divided into two types, such that
infrequently changed state belongs in a separate "BigState" structure
that is only allocated and attached to a material when necessary.
CoglMaterialLayers are another sparse structure. Like CoglMaterials they
represent a diff against their parent and all the layers are part of
another graph with the "default_layer_0" layer being the root node that
Cogl creates during initialization.
Copying a material is now basically just a case of slice allocating a
CoglMaterial, setting the parent to be the source being copied and
zeroing the mask of changes.
Flush overrides should now be handled by simply relying on the cheapness
of copying a material and making changes to it. (This will be done in a
follow on commit)
Weak material support will be added in a follow on commit.
We were incorrectly guarding the use of GL_TEXTURE_RECTANGLE_ARB with
ifdef ARB_texture_rectangle instead of ifdef GL_ARB_texture_rectangle
which broke test-cogl-texture-rectangle.
This was mistakenly added some time ago because at some point when we
were discussing how to handle premultiplied alpha in Clutter/Cogl we
were considering having a magic "just do the right thing" option which
was later abandoned.
This is to try and improve API consistency. Simple cogl structures that
don't derive from CoglObject and which can be allocated on the stack,
such as CoglColor and CoglMatrix should all have "_init" or
"_init_from" functions to initialize all the structure members. (As
opposed to a cogl_xyz_new() function for CoglObjects). CoglColor
previously used the naming scheme "_set_from" for these initializers but
"_set" is typically reserved for setting individual properties of a
structure/object.
This adds three _init functions:
cogl_color_init_from_4ub
cogl_color_init_from_4f
cogl_color_init_from_4fv
The _set_from functions are now deprecated but only with a gtk-doc
annotation for now. This is because the cogl_color_set_from API is quite
widely used already and so were giving a grace period before enabling a
GCC deprecated warning just because otherwise the MX maintainers will
complain to me that I've made their build logs look messy.
The journal logs colors as 4bytes into a vertex array and since we are
planning to make CoglMaterial track its color using a CoglColor instead
of a byte array this convenience will be useful for re-implementing
_cogl_material_get_colorubv.
Some internal symbols used for the GLES 2 wrapper were accidentally
being exported. This prepends an underscore to them so they won't
appear in the shared library.
Whenever a path or a rectangle is added to the clip stack it now also
stores a screen space bounding box in the entry. Then when the clip
stack is flushed the bounding box is first used to set up the
scissor. That way when we eventually come to use the stencil buffer
the clear will be affected by the scissor so we don't have to clear
the entire buffer.
_cogl_path_get_bounds is no longer static and is exported in
cogl-path-private.h so that it can be used in the clip stack code. The
old version of the function returned x/y and width/height. However
this was mostly used to call cogl_rectangle which takes x1/y1
x2/y2. The function has been changed to just directly return the
second form because it is more useful. Anywhere that was previously
using the function now just directly looks at path->path_nodes_min and
path->path_nodes_max instead.
The transform_point function takes a modelview matrix, projection
matrix and a viewport and performs all three transformations on a
point to give a Cogl window coordinate. This is useful in a number of
places in Cogl so this patch moves it to cogl.c and adds it to
cogl-internal.h
For sliced 2D textures, _cogl_texture_2d_sliced_get_data() uses the
bitmap width, instead of the rowstride, when memcpy()ing into the
dest buffer.
Signed-off-by: Robert Bragg <robert@linux.intel.com>
We only had getters for the red, green, blue and alpha channels of a
color. This meant that, if you wanted to change, say, the alpha
component of a color, one would need to query the red, green and blue
channels and use set_from_4ub() or set_from_4f().
Instead of this, just provide some setters for CoglColor, using the same
naming scheme than the existing getters.
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);
Previously a path copy was implemented such that only the array of
path nodes was shared with the source and the rest of the data is
copied. This was so that the copy could avoid a deep copy if the
source path is appended to because the copy keeps track of its own
length. This optimisation is probably not worthwhile because it makes
the copies less cheap. Instead the CoglPath struct now just contains a
single pointer to a new CoglPathData struct which is separately
ref-counted. When the path is modified it will be copied if the ref
count on the data is not 1.
Since framebuffer state is not flushed prior to replaying the journal,
the trick of marking the framebuffer dirty prior to calling
glBindFramebuffer() doesn't work... the outstanding journal entries
will get replayed to the newly created framebuffer.
Fix this by flushing the journal as well.
http://bugzilla.openedhand.com/show_bug.cgi?id=2110
Signed-off-by: Robert Bragg <robert@linux.intel.com>
If the clip stack is empty then _cogl_clip_stack_flush exits
immediately. This was missing out the assignment of *stencil_used_p at
the bottom of the function. If a path is then used after the clip is
cleared then it would think it needs to merge with the clip so the
stencil would not be cleared correctly.
Instead of using cogl_get_bitmasks() to query the GL machinery for the
size of the color bits, we should store the values inside the
CoglFramebuffer object and query them the first time we set the framebuffer
as the current one.
Currently, cogl_get_bitmasks() is re-implemented in terms of
cogl_framebuffer_get_*_bits(). As soon as we are able to expose the
CoglOnscreen framebuffer object in the public API we'll be able to
deprecate cogl_get_bitmasks() altogether.
http://bugzilla.openedhand.com/show_bug.cgi?id=2094
In 91cde78a7 I accidentally changed the function names that get looked
up for the framebuffer extension under GLES so that they didn't have
any suffix. The spec for extension specifies that they should have the
OES suffix.
Debugging code is not meant to be run in the nominal code path. Use
G_UNLIKELY to be reduce the number of bubbles in the instruction
pipeline.
Took the opportunity to re-indent the macros.
When uploading texture data the cogl-texture-2d-sliced backend was
using _cogl_texture_prepare_for_upload to create a bitmap suitable for
upload but then it was using the original bitmap instead of the new
bitmap for the data. This was causing any format conversions performed
by cogl_texture_prepare_for_upload to be ignored.
http://bugzilla.openedhand.com/show_bug.cgi?id=2059
In commit abe91784c4 I changed cogl-texture so that it would use the
OpenGL mechanism to specify a different internal texture format from
the image format so that it can do the conversion instead of
Cogl. However under GLES the internal format and the image format must
always be the same and it only supports a limited set of formats. This
patch changes _cogl_texture_prepare_for_upload so that it does the
conversion using the cogl bitmap code when compiling for GLES.
http://bugzilla.openedhand.com/show_bug.cgi?id=2059
There was a check at the bottom of the loop which sets up the state
for each of the layers so that it would break from the loop when the
maximum number of layers is reached. However after doing this it would
not increment 'i'. 'i' is later used to disable the remaining layers
so it would end up disabling the last layer it just set up.
This patch moves the check to be part of the loop condition so that
the check is performed after incrementing 'i'.
http://bugzilla.openedhand.com/show_bug.cgi?id=2064
The warning displayed when too many layers are used had an off-by-one
error so that it would display even if exactly the maximum number is
used. There was also a missing space at the end of the line in the
message which looked wrong when displayed on the terminal.
http://bugzilla.openedhand.com/show_bug.cgi?id=2064
cogl_path_arc_rel was never in any public headers so it isn't part of
the public API. It also has a slightly inconsistent name because the
rest of the relative path functions are called cogl_path_rel_*. This
patch makes it static for now to make it more obvious that it isn't
public. The name has changed to _cogl_path_rel_arc.
If a path is copied and then appended to, the copy needs to have the
last sub path truncated so that it fits in the total path size in case
the original path was modified. However the path size check was broken
so if the copied path had more than one sub path it would fail.
Previously the clip stack code was trying to detect when the
orientation of the on-screen rectangle had changed by checking if the
order of the y-coordinates on the left edge was different from the
order the x-coordinates on the top edge. This doesn't work for some
rotations which was causing the clip planes to clip the wrong side of
the line. This patch makes it detect the orientation by calculating
the signed area which is a standard computer graphics algorithm.
http://bugzilla.openedhand.com/show_bug.cgi?id=2079
When drawing a path with only a single sub path, Cogl uses the
'even-odd' fill rule which means that if a part of the path intersects
with another part then the intersection would be inverted. However
when combining sub paths it treats them as separate paths and then
unions them together. This doesn't match the semantics of the even-odd
rule in SVG and Cairo. This patch makes it so that a new sub path is
just drawn as another triangle fan so that it will continue to invert
the stencil buffer. This is also much simpler and more efficient as
well as being more correct.
http://bugzilla.openedhand.com/show_bug.cgi?id=2088
Under GLES glReadPixels is documented to only support GL_RGBA with
GL_UNSIGNED_BYTE and an implementation specfic format which can be
fetched with glGet, GL_IMPLEMENTATION_COLOR_READ_FORMAT_OES and
GL_IMPLEMENTATION_COLOR_READ_TYPE_OES. This patch makes it always read
using GL_RGBA and GL_UNSIGNED_BYTE and then convert the results if
neccessary.
This has some room for improvement because it doesn't attempt to use
the implementation specific format. Also the conversion is somewhat
wasteful because there are currently no cogl_bitmap_* functions to
convert without allocating a new buffer so it ends up doing an
intermediate copy.
http://bugzilla.openedhand.com/show_bug.cgi?id=2057
_cogl_bitmap_convert_format_and_premult was failing when converting
from RGBA to RGB and vice versa. _cogl_bitmap_fallback_convert
converts without altering the premult status so when choosing a new
format it would copy over the premult bit. However, it did this
regardless of whether the new format had an alpha channel so when
converting from RGBA_8888_PRE to RGB_888 it would end up inventing a
new meaningless format which would be RGB_888_PRE. This patch makes it
avoid copying the premult flag if the destination has no alpha. It
doesn't matter if it copies when the source format has no alpha
because it will always be unset.
_cogl_bitmap_convert_format_and_premult was also breaking when
converting from RGBA_8888_PRE to RGB_888 because it would think
RGB_888 is unpremultiplied and try to convert but then
_cogl_bitmap_fallback_premult wouldn't know how to do the conversion.
http://bugzilla.openedhand.com/show_bug.cgi?id=2057
This adds three new internal API functions which can be used to retain
the clip stack state and restore it later:
_cogl_get_clip_stack
_cogl_set_clip_stack
_cogl_clip_stack_copy
The functions are currently internal and not yet used but we may want
to make them public in future to replace the cogl_clip_stack_save()
and cogl_clip_stack_restore() APIs.
The get function just returns the handle to the clip stack at the top
of the stack of stacks and the set function just replaces it.
The copy function makes a cheap copy of an existing stack by taking a
reference to the top stack entry. This ends up working like a deep
copy because there is no way to modify entries of a stack but it
doesn't actually copy the data.
CoglClipStackState has now been renamed to CoglClipState and is moved
to a separate file. CoglClipStack now just maintains a stack and
doesn't worry about the rest of the state. CoglClipStack sill contains
the code to flush the stack to GL.
When glScissor is called it needs to pass coordinates in GL's
coordinate space where the origin is the bottom left. Previously this
conversion was done before storing the window rect in the clip
stack. However this might make it more difficult if we want to be able
to grab a handle to a clip stack and use it in different circumstances
later. This patch moves the coordinate conversion to inside the clip
state flushing code.
The stack is now stored as a list of reference counted entries.
Instead of using a GList, each entry now contains a link with a
reference to its parent. The idea is that this would allow copying
stacks with a shared ancestry.
Previously the code flushed the state by finding the bottom of the
stack and then applying each entry by walking back up to the top. This
is slightly harder to do now because the list is no longer
doubly-linked. However I don't think it matters which order the
entries are applied so I've just changed it to apply them in reverse
order.
There was also a restriction that if ever the stencil buffer is used
then we could no longer use clip planes for any subsequent entries. I
don't think this makes sense because it should always work as long as
it doesn't attempt to use the clip planes more than once. I've
therefore removed the restriction.
The CoglAtlasTexture struct was not being freed in
_cogl_atlas_texture_free so there would be a small leak whenever a
texture was destroyed.
Thanks to Robert Bragg for spotting this.
CoglMaterial now sets GL_CLAMP_TO_EDGE if WRAP_MODE_AUTOMATIC is used
unless it is overridden when the material is flushed. The primitives
are still expected to expose repeat semantics so no user visible
changes are made. The idea is that drawing non-repeated textures is
the most common case so if we make clamp_to_ege the default then we
will reduce the number of times we have to override the
material. Avoiding overrides will become important if the overriding
mechanism is replaced with one where the primitive is expected to copy
the material and change that instead.
Previously, Cogl's texture coordinate system was effectively always
GL_REPEAT so that if an application specifies coordinates outside the
range 0→1 it would get repeated copies of the texture. It would
however change the mode to GL_CLAMP_TO_EDGE if all of the coordinates
are in the range 0→1 so that in the common case that the whole texture
is being drawn with linear filtering it will not blend in edge pixels
from the opposite sides.
This patch adds the option for applications to change the wrap mode
per layer. There are now three wrap modes: 'repeat', 'clamp-to-edge'
and 'automatic'. The automatic map mode is the default and it
implements the previous behaviour. The wrap mode can be changed for
the s and t coordinates independently. I've tried to make the
internals support setting the r coordinate but as we don't support 3D
textures yet I haven't exposed any public API for it.
The texture backends still have a set_wrap_mode virtual but this value
is intended to be transitory and it will be changed whenever the
material is flushed (although the backends are expected to cache it so
that it won't use too many GL calls). In my understanding this value
was always meant to be transitory and all primitives were meant to set
the value before drawing. However there were comments suggesting that
this is not the expected behaviour. In particular the vertex buffer
drawing code never set a wrap mode so it would end up with whatever
the texture was previously used for. These issues are now fixed
because the material will always set the wrap modes.
There is code to manually implement clamp-to-edge for textures that
can't be hardware repeated. However this doesn't fully work because it
relies on being able to draw the stretched parts using quads with the
same values for tx1 and tx2. The texture iteration code doesn't
support this so it breaks. This is a separate bug and it isn't
trivially solved.
When flushing a material there are now extra options to set wrap mode
overrides. The overrides are an array of values for each layer that
specifies an override for the s, t or r coordinates. The primitives
use this to implement the automatic wrap mode. cogl_polygon also uses
it to set GL_CLAMP_TO_BORDER mode for its trick to render sliced
textures. Although this code has been added it looks like the sliced
trick has been broken for a while and I haven't attempted to fix it
here.
I've added a constant to represent the maximum number of layers that a
material supports so that I can size the overrides array. I've set it
to 32 because as far as I can tell we have that limit imposed anyway
because the other flush options use a guint32 to store a flag about
each layer. The overrides array ends up adding 32 bytes to each flush
options struct which may be a concern.
http://bugzilla.openedhand.com/show_bug.cgi?id=2063
GL supports setting different wrap modes for the s, t and r
coordinates so we should design the backend interface to support that
also. The r coordinate is not currently used by any of the backends
but we might as well have it to make life easier if we ever add
support for 3D textures.
http://bugzilla.openedhand.com/show_bug.cgi?id=2063
CoglColor and CoglMatrix have public declarations with private members
so that we are free to change the implementation but the structures
could still be allocated on the stack in applications. However it's
quite easy not to realise the members are private and then access them
directly. This patch wraps the members in a macro which redefines the
symbol name when including the header outside of the clutter source.
http://bugzilla.openedhand.com/show_bug.cgi?id=2065
The xx, yx, zx etc fields are meant to be read-only but they were
marked as private with the gtk-doc annotation. This patch moves the
private marker so that the 16 float member fields are public but the
type, inverted matrix, flags and padding are not.
This adds three new API calls:
CoglHandle cogl_path_get()
void cogl_path_set(CoglHandle path)
CoglHandle cogl_path_copy(CoglHandle path)
All of the fields relating to the path have been moved from the Cogl
context to a new CoglPath handle type. The cogl context now just
contains a CoglPath handle. All of the existing path commands
manipulate the data in the current path handle. cogl_path_new now just
creates a new path handle and unrefs the old one.
The path handle can be stored for later with cogl_path_get. The path
can then be copied with cogl_path_copy. Internally it implements
copy-on-write semantics with an extra optimisation that it will only
copy the data if the new path is modified, but not if the original
path is modified. It can do this because the only way to modify a path
is by appending to it so the copied path is able to store its own path
length and only render the nodes up to that length. For this to work
the copied path also needs to keep its own copies of the path extents
because the parent path may change these by adding nodes.
The clip stack now uses the cogl_path_copy mechanism to store paths in
the stack instead of directly copying the data. This should save some
memory and processing time.
Although cogl_multiply_matrix was consistent with OpenGL, after further
consideration it was agreed that cogl_transform is a better name. Given
that it's in the global cogl_ namespace cogl_transform seems more self
documenting.
This adds an example of how to setup a Clutter style 2D coordinate space
and clarifies what state is owned by a framebuffer. (projection,
modelview, viewport and clip stack)
When we expose more cogl_framebuffer API this example will hopefully be
migrated into a more extensive introduction to using framebuffers.
