Major refactoring.
1. Rewrite the pixmap texture uploading and downloading functions.
   Add some new functions for both the prepare/finish access and
   the new performance feature dynamic texture uploading, which
   could download and upload the current image to/from a private
   texture/fbo. In the uploading or downloading phase, we need to
   handle two things:
   The first is the yInverted option, If it set, then we don't need
   to flip y. If not set, if it is from a dynamic texture uploading
   then we don't need to flip either if the current drawing process
   will flip it latter. If it is from finish_access, then we must
   flip the y axis.

   The second thing is the alpha channel hanlding, if the pixmap's
   format is something like x8a8r8g8, x1r5g5b5 which means it doesn't
   has alpha channel, but it do has those extra bits. Then we need to
   wire those bits to 1.

2. Add almost all the required picture format support.
   This is not as trivial as it looks like. The previous implementation
   only support GL_a8,GL_a8r8g8b8,GL_x8r8g8b8. All the other format,
   we have to fallback to cpu. The reason why we can't simply add those
   other color format is because the exists of picture. one drawable
   pixmap may has one or even more container pictures. The drawable pixmap's
   depth can't map to a specified color format, for example depth 16 can
   mapped to r5g6b5, x1r5g5b5, a1r5g5b5, or even b5g6r5. So we can't get
   get the color format just from the depth value. But the pixmap do not
   has a pict_format element. We have to make a new one in the pixmap
   private data structure. Reroute the CreatePicture to glamor_create_picture
   and then store the picture's format to the pixmap's private structure.

   This is not an ideal solution, as there may be more than one pictures
   refer to the same pixmap. Then we will have trouble. There is an example
   in glamor_composite_with_shader. The source and mask often share the
   same pixmap, but use different picture format. Our current solution is to
   combine those two different picture formats to one which will not lose any
   data. Then change the source's format to this new format and then upload
   the pixmap to texture once. It works. If we fail to find a matched new
   format then we fallback.

   There still is a potential problem, if two pictures refer to the same
   pixmap, and one of them destroy the picture, but the other still remained
   to be used latter. We don't handle that situation currently. To be fixed.

3. Dynamic texture uploading.
   This is a performance feature. Although we don't like the client to hold
   a pixmap data to shared memory and we can't accelerate it. And even worse,
   we may need to fallback all the required pixmaps to cpu memory and then
   process them on CPU. This feature is to mitigate this penalty. When the
   target pixmap has a valid gl fbo attached to it. But the other pixmaps are
   not. Then it will be more efficient to upload the other pixmaps to GPU and
   then do the blitting or rendering on GPU than fallback all the pixmaps to CPU.
   To enable this feature, I experienced a significant performance improvement
   in the Game "Mines" :).

4. Debug facility.
   Modify the debug output mechanism. Now add a new macro:
   glamor_debug_output(_level_, _format_,...) to conditional output some messages
   according to the environment variable GLAMOR_DEBUG. We have the following
   levels currently.
    exports GLAMOR_DEBUG to 3 will enable all the above messages.

5. Changes in pixmap private data structure.
   Add some for the full color format supports and relate it to the pictures which
   already described. Also Add the following new elements:
   gl_fbo - to indicates whether this pixmap is on gpu only.
   gl_tex - to indicates whether the tex is valid and is containing the pixmap's
            image originally.
   As we bring the dynamic pixmap uploading feature, so a cpu memory pixmap may
   also has a valid fbo or tex attached to it. So we will have to use the above
   new element to check it true type.

After this commit, we can pass the rendercheck testing for all the picture formats.
And is much much fater than fallback to cpu when doing rendercheck testing.
Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

    This commit was borrowed from uxa driver contributed by Eric.
    commit number is e0066e77e026b0dd0daa0c3765473c7d63aa6753. commit log paste as
    below:
    We were clipping each span against the bounds of the clip, throwing
    out the span early if it was all clipped, and then walked the clip box
    clipping against each of the cliprects.  We would expect spans to
    typically be clipped against one box, and not thrown out, so we were
    not saving any work there.  For multiple cliprects, we were adding
    work.  Only for many spans clipped entirely out of a complicated clip
    region would it have saved work, and it clearly didn't save bugs as
    evidenced by the many fix attempts here.
Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

It's better to give a correct output when we haven't
implement all the code path.
Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

The previous implementation will just skip the rendering
which is not good.
Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

By default, fallback to frame buffer currently. This commit
makes us pass the rendercheck's triangles testing.
Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

For 1bpp pixmap, software fb get better performance than
GL surface. The main reason is that fbo doesn't support
1bpp texture as internal format, so we have to translate
a 1bpp bitmap to a 8bit alpha format each time which is
very inefficient. And the previous implementation is
not supported by the latest OpenGL 4.0, the GL_BITMAP
was deprecated.
Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

Added a new shader aswizlle_prog to wired the alpha to 1 when
the image color depth is 24 (xrgb). Then we don't need to fallback
the xrgb source/mask to software composite in render phase. Also
don't wire the alpha bit to 1 in the render phase. This can get
about 2x performance gain with the cairo performance trace's
firefox-planet case.
Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

use pbo if possible when we load texture to a temporary tex.
And for the previous direct texture load function, it's not
correct and get removed in this commit.
Signed-off-by: Zhigang Gong <zhigang.gong@linux.intel.com>

Added comments to glamor_pixmap_create. To be refined in the future.
We need to identify whether a pixmap is a CPU memory pixmap or a
GPU pixmap. Current implementation is not correct. There are three
cases:

1. Too large pixmap, we direct it to CPU memory pixmap.
2. w ==0 ||  h == 0 pixmap, this case has two possibilities:
   2.1 It will become a screen pixmap latter, then it should be
       GPU type.
   2.2 It's a scratch pixmap or created from a share memory, then
       it should belong to CPU memory.

XXX, need to be refined latter.

When the platform's coordinate system is the same as X11's . We
can load the texture to the fbo directly without one extra texture
transformation.

For those pixmap which has valid fbo and opened as GLAMOR_ACCESS_RO
mode, we don't need to upload the texture back when calling the
glamor_finish_access(). This will get about 10% performance gain.

Change the row length of 1bit color depth pixmap to the actual stride.
The previous implementation use the width as its stride which is not
good. As it will waste 8 times of space and also bring some non-unify
code path. With this commit, we can merge those 1bit or other color
depth to almost one code path. And we will use pixel buffer object
as much as possible due to performance issue. By default, some mesa
hardware driver will fallback to software rasterization when use
glReadPixels on a non-buffer-object frame buffer. This change will
get about 4x times performance improvemention when we use y-inverted
glamor or the driver support hardware y-flipped blitting.

GL_COLOR_OP seems not supported in current MESA.

If pixmap's size exceeds the limitation of the MESA library, the
rendering will fail. So we switch to software fb if it is the case.
Add one new element for pixmap private structure to indicate whehter
we are a software fb type or a opengl type.

This commit fixed two bugs when one client reset the connection.
The first is that we should reopen the graphic device when the previous
node was closed during the screen closing. The second one is we should
call glamor_close_screen (not the ddx version) prior to call
eglTerminate(). As eglTerminate will release the share library. And
the glamor_close_screen may still need to call openGL APIs and thus
will hit segfault. And renamed the ddx functions to avoid naming
conflications with the glamor functions.

those xcalloc/xfree/xalloc/XNFprintf/... are deprecated. Replace
then with the new one. And fix some other minor problems.

Cursor is a per crtc resource. And this commit also fix the cursor
initialization regard to the latest mesa EGL code. Now hardware
cursor works fine.

GC is redefined in the X11/Xlib.h and include/gcstruct.h which is
a xorg header file. Just use a macro to simply avoid the conflict.
Need revisit latter to find a correct way to fix this problem.

Use eglCreateDRMImageMESA to create surfaceless image. And then
export the drm buffer back which can be used to create the frame
buffer.

Due to the coordinate system on EGL is different from FBO
object. To support EGL surface well, we add this new feature.
When calling glamor_init from EGL ddx driver, it should use
the new flag GLAMOR_INVERTED_Y_AXIS.

Correct the linking parameters and add dependency to the libglamor.a.

move the original glamor_fini to glamor_close_screen. And wrap the CloseScreen
with glamor_close_screen, Then we can do some thing before call the underlying
CloseScreen().
The root cause is that glamor_fini will be called after the ->CloseScreen().
This may trigger a segmentation fault at
glamor_unrealize_glyph_caches() at calling into FreePicture().

As current glamor implementation depends on the glx library in the
mesa package which is conflict with the version in xorg. We have to
--disable-glx when build Xephyr. But this leads to the linking error
here. We comment out the calling to ephyrHijackGLXExtension() now.
Need revisit latter.

Merged with latest xserver, the major change is due to the API change of
the management of devPrivates.

We should include the dix-config.h for all the glamor files. Otherwise
the XID type maybe inconsisitent in different files in 64bit machine.
The root cause is this macro "#define _XSERVER64 1" should be included
in all files refer to the data type "XID" which is originally defined
in X.h. If _XSERVER64 is defined as 1, then XID is defined as CARD32
which is a 32bit integer. If _XSERVER64 is not defined as 1 then XID
is "unsigned long". In a 32bit machine, "unsigned long" should be
identical to CARD32. But in a 64bit machine, they are different.

Change the inline functions to static type, otherwise when linking it
complains multiple definitions of those functions.

This increases us from 23000 to 27000/sec on rgb24text.

This shaves CPU time in GL setup.  Performance of rgb24text went from
18400/sec to 23500/sec.