Commit Graph

885 Commits

Author SHA1 Message Date
Anton Kindestam a776628d88 drm_common: Add option to toggle use of atomic modesetting
It is useful when debugging to be able to force atomic off, or as a
workaround if atomic breaks for some user. Legacy modesetting is less
likely to break by virtue of being a less complex API.
2019-05-04 14:17:11 +02:00
Philip Langdale 23a324215b vo/gpu: hwdec_cuda: Refactor gpu api specific code into separate files
The amount of code now present that's specific to Vulkan or OpenGL
has reached the point where we really want to split it out to
avoid a mess of #ifdefs.

At the same time, I'm moving the code to an api neutral location.
2019-05-03 18:02:18 +02:00
Anton Kindestam 738fda3677 context_drm_egl: Add support for presentation feedback
This implements presentation feedback for context_drm_egl using the
values that get fed to the page flip handler.
2019-05-03 18:01:56 +02:00
Jan Ekström edbc199914 vo_gpu/hwdec_cuda: fixup compilation with vulkan disabled
The actual code utilizing this enum was seemingly properly if'd,
but not the enum in the struct itself.

Fixes compilation.
2019-04-22 18:17:30 +03:00
Philip Langdale 74831dd651 vo/gpu: hwdec_cuda: Reorganise backend-specific code
This tries to tidy up the GL vs Vulkan code to be a bit cleaner
and easier to read.
2019-04-21 23:55:22 +03:00
Philip Langdale 4005cda614 vo_gpu: hwdec_cuda: Implement interop for placebo
This change updates the vulkan interop code to work with the
libplacebo based ra_vk, but also introduces direct VkImage
sharing to avoid the use of the intermediate buffer.

It is also necessary and desirable to introduce explicit
semaphore bsed synchronisation for operations on the shared
images.

Synchronisation means we can safely reuse the same VkImage for every
mapped frame, by ensuring the frame is copied to the VkImage before
mapping the next frame.

This functionality requires a 417.xx or newer nvidia driver, due to
bugs in the VkImage interop in the earlier 411 and 415 drivers.

It's definitely worth the effort, as the raw throughput is about
twice that of implementation using an intermediate buffer.
2019-04-21 23:55:22 +03:00
Niklas Haas 7006d6752d vo_gpu: vulkan: use libplacebo instead
This commit rips out the entire mpv vulkan implementation in favor of
exposing lightweight wrappers on top of libplacebo instead, which
provides much of the same except in a more up-to-date and polished form.

This (finally) unifies the code base between mpv and libplacebo, which
is something I've been hoping to do for a long time.

Note: The ra_pl wrappers are abstract enough from the actual libplacebo
device type that we can in theory re-use them for other devices like
d3d11 or even opengl in the future, so I moved them to a separate
directory for the time being. However, the rest of the code is still
vulkan-specific, so I've kept the "vulkan" naming and file paths, rather
than introducing a new `--gpu-api` type. (Which would have been ended up
with significantly more code duplicaiton)

Plus, the code and functionality is similar enough that for most users
this should just be a straight-up drop-in replacement.

Note: This commit excludes some changes; specifically, the updates to
context_win and hwdec_cuda are deferred to separate commits for
authorship reasons.
2019-04-21 23:55:22 +03:00
Niklas Haas f0b6860d62 vo_gpu: index desc namespaces by ra
No reason to require them be constant. This allows them to depend on
runtime characteristics of the `ra`.
2019-04-21 23:55:22 +03:00
Jan Ekström 199aabddcc Merge branch 'master' into pr6360
Manual changes done:
  * Merged the interface-changes under the already master'd changes.
  * Moved the hwdec-related option changes to video/decode/vd_lavc.c.
2019-03-11 01:00:27 +02:00
Anton Kindestam 537006965e context_drm_egl: implement n-buffering
This allows context_drm_egl to use as many buffers as libgbm or the
swapchain_depth setting allows (whichever is smaller).

On pause and on still images (cover art etc.) to make sure that output does not
lag behind user input, the swapchain is drained and reverts to working in a dual
buffered (equivalent to swapchain-depth=1) manner.

When possible (swapchain-depth>=2), the wait on the page flip event is now not
done immediately after queueing, but is deferred to the next invocation of
swap_buffers. Which should give us more CPU time between invocations.

Although, since gbm_surface_has_free_buffers() can only tell us a boolean value
and not how many buffers we have left, we are forced to do this contortionist
dance where we first overshoot until gbm_surface_has_free_buffers() reports 0,
followed by immediately waiting so we can free a buffer, to be able to get the
deferred wait on page flip rolling.

With this commit we do not rely on the default vsync fences/latency emulation of
video/out/opengl/context.c, but supply our own, since the places we create and
wait for the fences needs to be somewhat different for best performance.

Minor fixes:

 * According to GBM documentation all BO:s gotten with
   gbm_surface_lock_front_buffer must be released before gbm_surface_destroy is
   called on the surface.
 * We let the page flip handler function handle the waiting_for_flip flag.
2019-02-25 01:25:25 +01:00
Anton Kindestam ae115bd8d8 opengl: Support GL_ARB_sync style fences on OpenGL ES 3.0
OpenGL ES 3.0 and up has suppport for for GL_ARB_sync style fences.
Make sure that mpv can use them.
2019-02-25 01:25:25 +01:00
wm4 f4ce3b8bb9 vo, vo_gpu, glx: correct GLX_OML_sync_control usage
I misunderstood how this extension works. If I understand it correctly
now, it's worse than I thought. They key thing is that the (ust, msc,
sbc) tripple is not for a single swap event. Instead, (ust, msc) run
independently from sbc. Assuming a CFR display/compositor, this means
you can at best know the vsync phase and frequency, but not the exact
time a sbc changed value.

There is GLX_INTEL_swap_event, which might work as expected, but it has
no EGL equivalent (while GLX_OML_sync_control does, in theory).

Redo the context_glx sync code. Now it's either more correct or less
correct. I wanted to add proper skip detection (if a vsync gets skipped
due to rendering taking too long and other problems), but it turned out
to be too complex, so only some unused fields in vo.h are left of it.
The "generic" skip detection has to do.

The vsync_duration field is also unused by vo.c.

Actually this seems to be an improvement. In cases where the flip call
timing is off, but the real driver-level timing apparently still works,
this will not report vsync skips or higher vsync jitter anymore. I could
observe this with screenshots and fullscreen switching. On the other
hand, maybe it just introduces an A/V offset or so.

Why the fuck can't there be a proper API for retrieving these
statistics? I'm not even asking for much.
2018-12-06 10:32:27 +01:00
wm4 b1ba7de34d vo: use a struct for vsync feedback stuff
So new useless stuff can be easily added.
2018-12-06 10:30:25 +01:00
wm4 83884fdf03 vo_gpu: glx: use GLX_OML_sync_control for better vsync reporting
Use the extension to compute the (hopefully correct) video delay and
vsync phase.

This is very fuzzy, because the latency will suddenly be applied after
some frames have already been shown. This means there _will_ be "jumps"
in the time accounting, which can lead to strange effects at start of
playback (such as making initial "dropped" etc. frames worse). The only
reasonable way to fix this would be running a few dummy frame swaps at
start of playback until the latency is known. The same happens when
unpausing.

This only affects display-sync mode.

Correct function was not confirmed. It only "looks right". I don't have
the equipment to make scientifically correct measurements.

A potentially bad thing is that we trust the timestamps we're receiving.
Out of bounds timestamps could wreak havoc. On the other hand, this will
probably cause the higher level code to panic and just disable DS.

As a further caveat, this makes a bunch of assumptions about UST
timestamps. If there are delayed frames (i.e. we skipped one or more
vsyncs), the latency logic is mostly reset. There is no attempt to make
the vo.c skipped vsync logic to use this. Also, the latency computation
determines a vsync duration, and there's no effort to reconcile or share
the vo.c logic for determining vsync duration.
2018-12-06 10:30:14 +01:00
Anton Kindestam f0509d3738 drm: rename plane options to better, invariant, names
This commit bumps the libmpv version to 1.102

drm-osd-plane -> drm-draw-plane
drm-video-plane -> drm-drmprime-video-plane
drm-osd-size -> drm-draw-surface-size

"draw plane", as in the plane that OpenGL draws to, whether it be
video + OSD or just OSD.

"drmprime video plane", as in the plane used for hwdec video imported
via drmprime.

"draw surface size", as in the size of the surface used for the draw plane

The new names are invariant whether or not hwdec_drmprime_drm is being
used or not. The original naming was very confusing, as when doing
regular rendering (swdec or vaapi) the video would be displayed on the
"OSD plane", and the "Video plane" would remain unused.
2018-12-01 15:42:20 +02:00
Philip Langdale 721bec7dde vo_gpu: hwdec_cuda: Guard GL and Vulkan headers properly
We are currently unnecessarily including vulkan headers even when
not building with vulkan support. I also guarded the GL header
inclusion even though this doesn't appear to break anything today.

Fixes #6330.
2018-11-18 23:50:38 +02:00
Niklas Haas 2704625e3f vo_gpu: opengl: disable compute shaders for old GLSL
Fixes #6272.
2018-11-17 00:49:10 +01:00
Philip Langdale 84d6638907 vo_gpu: hwdec_cuda: Clean up init() error handling
Currently, the error paths in init() are a bit confusing, and we can
end up trying to pop the current context when there is no context,
which leads to distracting error messages.

I also added an explicit path to return early if the GPU backend is
not OpenGL or Vulkan. It's pointless to do any other cuda init
after that point. (Of course, someone could write more interops.)

Fixes #6256
2018-10-31 09:20:06 +01:00
Anton Kindestam ba2dee38fb hwdec_drmprime_drm: Missing NULL-check on drm_atomic_context video_plane
Since 810acf32d6 video_plane can be NULL
under some circumstances. While there is a check in init, init treats
this as an error condition and would call uninit, which in turn calls
disable_video_plane, which would then segfault. Fix this by including
a NULL check inside disable_video_plane, so that it doesn't try to
disable what isnt' there.
2018-10-25 13:50:09 +02:00
Philip Langdale da1073c247 vo_gpu: vulkan: hwdec_cuda: Add support for Vulkan interop
Despite their place in the tree, hwdecs can be loaded and used just
fine by the vulkan GPU backend.

In this change we add Vulkan interop support to the cuda/nvdec hwdec.

The overall process is mostly straight forward, so the main observation
here is that I had to implement it using an intermediate Vulkan buffer
because the direct VkImage usage is blocked by a bug in the nvidia
driver. When that gets fixed, I will revist this.

Nevertheless, the intermediate buffer copy is very cheap as it's all
device memory from start to finish. Overall CPU utilisiation is pretty
much the same as with the OpenGL GPU backend.

Note that we cannot use a single intermediate buffer - rather there
is a pool of them. This is done because the cuda memcpys are not
explicitly synchronised with the texture uploads.

In the basic case, this doesn't matter because the hwdec is not
asked to map and copy the next frame until after the previous one
is rendered. In the interpolation case, we need extra future frames
available immediately, so we'll be asked to map/copy those frames
and vulkan will be asked to render them. So far, harmless right? No.

All the vulkan rendering, including the upload steps, are batched
together and end up running very asynchronously from the CUDA copies.

The end result is that all the copies happen one after another, and
only then do the uploads happen, which means all textures are uploaded
the same, final, frame data. Whoops. Unsurprisingly this results in
the jerky motion because every 3/4 frames are identical.

The buffer pool ensures that we do not overwrite a buffer that is
still waiting to be uploaded. The ra_buf_pool implementation
automatically checks if existing buffers are available for use and
only creates a new one if it really has to. It's hard to say for sure
what the maximum number of buffers might be but we believe it won't
be so large as to make this strategy unusable. The highest I've seen
is 12 when using interpolation with tscale=bicubic.

A future optimisation here is to synchronise the CUDA copies with
respect to the vulkan uploads. This can be done with shared semaphores
that would ensure the copy of the second frames only happens after the
upload of the first frame, and so on. This isn't trivial to implement
as I'd have to first adjust the hwdec code to use asynchronous cuda;
without that, there's no way to use the semaphore for synchronisation.
This should result in fewer intermediate buffers being required.
2018-10-22 21:35:48 +02:00
Niklas Haas 104b510774 vo_gpu: opengl: fix segfault when gl->DeleteSync is unavailable
This deinit code was never checked, so this line would always crash on
implementations without support for sync objects.

Fixes #6197.
2018-10-16 01:57:49 +03:00
Akemi 8d2d0f0640 cocoa-cb: add Apple Software Renderer support
by default the pixel format creation falls back to software renderer
when everything fails. this is mostly needed for VMs. additionally one
can directly request an sw renderer or exclude it entirely.
2018-09-30 17:13:34 +03:00
Anton Kindestam 810acf32d6 drm_atomic: Allow to create atomic context w/o drmprime video plane
This is to improve the experience when running with default settings
on a driver that doesn't have any overlay planes (or indeed only one
plane), but still supports DRM atomic. Since the drmprime video plane
is set to pick an overlay plane by default it would fail on these
drivers due to not being able to create any atomic context. Users with
such cards had to specify --drm-video-plane-id manually to some bogus
value (it's not used after all).

The "video" plane is only ever used by the drmprime-drm hwdec interop,
which is not used at all in the typical usecase where everything is
actually rendered on to the "OSD" plane using EGL, so having an atomic
context without the "video" plane should be fine most of the time.
2018-09-30 14:22:49 +03:00
Anton Kindestam 351c083487 hwdec_vaegl: Fix VAAPI EGL interop used with gpu-context=drm
Add another parameter to mpv_opengl_drm_params to hold the FD to the
render node, so that the fd can be passed to hwdec_vaegl.

The render node is opened in context_drm_egl and inferred from the
primary device fd using drmGetRenderDeviceNameFromFd.
2018-07-09 02:33:35 +03:00
Anton Kindestam 7beee68f8d context_drm_egl: Fix CRTC setup and release code when using atomic
The previous code did not save enough information about the old state,
and could end up changing what plane the fbcon:s FB got attached to,
or in worse case causing a blank screen (observed in some multi-screen
setups on Sandy Bridge).

In addition refactor the handling of drmModeModeInfo property blobs to
not leak, as well as enable reuse of already created blobs.
2018-07-09 02:17:47 +03:00
Anton Kindestam 1298b9d201 context_drm_egl: Fix some memory leaks on error exit
Fix some memory leaks on error exit in crtc_setup_atomic and
crtc_release_atomic.
2018-07-09 02:17:47 +03:00
Anton Kindestam 157b242289 hwdec_drmprime_drm: Do not show error message during probing
Change the log-level of an error message that would sometimes show up
during hwdec probing, and could be misleading.
2018-06-08 22:13:39 +03:00
Anton Kindestam 4c6f36611d context_drm_egl: fix some comments and log messages that had not been updated since the plane rename commit 2018-05-01 20:48:02 +03:00
Anton Kindestam e60728a622 drm/atomic: Fix crtc_setup_atomic and crtc_release_atomic
Add some properties which where forgotten in crtc_setup_atomic.

In both change to not use DRM_MODE_PAGE_FLIP_EVENT | DRM_MODE_ATOMIC_NONBLOCK
flags. This should make it more similar to the drmSetCrtc which it aims to
replace (take effect directly, and blocking call). This also saves us the
trouble of having to set up a poll to wait for pageflip, which would've been
neccesary with DRM_MODE_PAGE_FLIP_EVENT, in both crtc_setup_atomic and
crtc_release_atomic.
2018-05-01 20:48:02 +03:00
LongChair ba3d90d9ed drm/atomic: disable video plane when unused.
This patch will make sure that the video plane is hidden when unused.
When using high resolution modes, typically UHD, and embedding mpv,
having the video plane sitting in the back when you don't play any video
is eating a lot of memory bandwidth for compositing.

That patch makes sure that the video layer is just disabled before and
after playback.
2018-05-01 20:48:02 +03:00
LongChair 1ccc56eff0 drm/atomic: add atomic modesetting.
This commit allows to add atomic modesetting when using the atomic renderer.
This is actually needed when using and osd with a smaller size than screen resolution.

It will also make the drm atomic path more consistent
2018-05-01 20:48:02 +03:00
LongChair ed94f8dc00 drm/atomic: refactor planes names
We are currently using primary / overlay planes drm objects, assuming that primary plane is osd and overlay plane is video.
This commit is doing two things :
  - replace the primary / overlay planes members with osd and video planes member without the assumption
  - Add two more options to determine which one of the primary / overlay is associated to osd / video.
  - It will default osd to overlay and video to primary if unspecified
2018-05-01 20:48:02 +03:00
LongChair 49bc07faea drm/atomic: add connector to atomic context
This patch adds
  - DRM connector object to atomic context.
  - fd property to the drm atomic object as well as a method to read blob type properties.

This allows to ensure that the proper connector is picked up, especially when specifying it
from the commandline, and also allows to make sure we're using the right one when embedding
with interop into an application.
2018-05-01 20:48:02 +03:00
LongChair 9f2970f28a drm/atomic: refactor hwdec_drmprime_drm with native resources
That new API was introduced and allows to have several native resources.
Thisuses that mechanisma for drm resources rather than the deprecated
opengl-cb structs.

This patch therefore add two structs that can be used with the drm atomic interop.
 - mpv_opengl_drm_params : which will hold all the drm handles
 - mpv_opengl_drm_osd_size : which will hold osd layer size

This commit adds a drm-osd-size=WxH parameter to commandline which
allows to define the OSD plane dimension. OSD can be upscaled to
screen resolution when having OSD at video resolution is too heavy.

This is especially useful for UHD modes on embedded devices where
the GPU cannot handle UHD modes at a decent framerate.
2018-05-01 20:48:02 +03:00
Akemi 6bd2bdc745 cocoa: change deprecation warning from opengl-cb to libmpv 2018-04-29 15:03:47 +03:00
wm4 eb33556cbf egl_helpers: change minimum framebuffer size to 8 bit per component
This is for working around bugs in certain Android devices. At least one
device fails to sort EGLConfigs by size, so eglChooseConfig() ends up
choosing a config with 5/6/5 bits per r/g/b component. The other
attributes in the affected EGLConfigs did not look like they should
affect the sorting process as specified by the EGL 1.4 standard.

The device was reported as:

Sony Xperia Z3 Tablet Compact
Firmware 6.0.1 build number 23.5.A.1.291
GL_VERSION='OpenGL ES 3.0 V@140.0 AU@ (GIT@I741a3d36ca)'
GL_VENDOR='Qualcomm'
GL_RENDERER='Adreno (TM) 330'

Other Qualcom/Adreno devices have been reported as unaffected by this
(including some with same GL_RENDERER string).

"Fix" this by always requiring at least 8 bit. This means it would fail
on devices which cannot provide this. We're fine with this.

mpv-android/mpv-android#112
2018-04-29 02:21:32 +03:00
wm4 67ce9813d6 egl_helpers: log certain EGL attributes
Might be helpful with broken EGL implementations.
2018-04-29 02:21:32 +03:00
Aman Gupta ed7bc3a5f3 hwdec_ios: fix crash after mapper_init failure 2018-04-17 01:06:29 +03:00
Philip Langdale 07915b1227 vo_gpu: hwdec: Use ffnvcodec to load CUDA symbols
The CUDA dynamic loader was broken out of ffmpeg into its own repo
and package. This gives us an opportunity to re-use it in mpv and
remove our custom loader logic.
2018-04-15 19:31:50 +03:00
Aman Gupta 9efb0278e7 opengl: include details in EGL context errors 2018-04-12 02:31:07 +03:00
wm4 52dd38a48a client API: add a new way to pass X11 Display etc. to render API
Hardware decoding things often need access to additional handles from
the windowing system, such as the X11 or Wayland display when using
vaapi. The opengl-cb had nothing dedicated for this, and used the weird
GL_MP_MPGetNativeDisplay GL extension (which was mpv specific and not
officially registered with OpenGL).

This was awkward, and a pain due to having to emulate GL context
behavior (like needing a TLS variable to store context for the pseudo GL
extension function). In addition (and not inherently due to this), we
could pass only one resource from mpv builtin context backends to
hwdecs. It was also all GL specific.

Replace this with a newer mechanism. It works for all RA backends, not
just GL. the API user can explicitly pass the objects at init time via
mpv_render_context_create(). Multiple resources are naturally possible.

The API uses MPV_RENDER_PARAM_* defines, but internally we use strings.
This is done for 2 reasons: 1. trying to leave libmpv and internal
mechanisms decoupled, 2. not having to add public API for some of the
internal resource types (especially D3D/GL interop stuff).

To remain sane, drop support for obscure half-working opengl-cb things,
like the DRM interop (was missing necessary things), the RPI window
thing (nobody used it), and obscure D3D interop things (not needed with
ANGLE, others were undocumented). In order not to break ABI and the C
API, we don't remove the associated structs from opengl_cb.h.

The parts which are still needed (in particular DRM interop) needs to be
ported to the render API.
2018-03-26 19:47:08 +02:00
LongChair b4c6fb0f52 drm/atomic: ensure request is available until uninit
Right now the atomic request is alive during the renderloop.

We want it to be alive until the drm egl context is destroyed because some properties
might still be set upon interop close

This patch make the request to be kept created even outside the renderloop.
The context uninit will commit the last request.
2018-03-23 00:44:47 +02:00
LongChair dae88644e6
hwdec_drmprime_drm: Fix a DRM buffer memory leakage
We use triple buffering for this interop and we were only unreffing the
data structures, which doesn't destroy the drm buffers.

This patch allows to make sure that we release the drm buffers on
playback end.
2018-03-05 23:33:45 -08:00
Anton Kindestam 33cffdcbac
context_drm_egl: Allow fallback EGLConfig formats
It turns out that Mali drivers are likely broken, and do not return
GBM_FORMAT_ARGB8888 (they return GBM_FORMAT_XRGB8888) when getting
EGL_NATIVE_VISUAL_ID for any EGLConfig, even though the resulting
EGLConfig appears to be capable of alpha.

It could also be potentially useful to allow an ARGB EGLConfig used
with an XRGB framebuffer on some platforms, so we do that. (cf. weston)

Unrelated indentation fix in gbm_format_to_string.
2018-03-04 16:56:06 -08:00
Niklas Haas ad3f6d2f97 vo_gpu: don't segfault in libmpv_gl's destroy()
This segfaults when the GPU context has not been fully initialized, such
as would be the case when initialization errors.
2018-03-04 00:17:00 -08:00
wm4 b037121430 client API: deprecate opengl-cb API and introduce a replacement API
The purpose of the new API is to make it useable with other APIs than
OpenGL, especially D3D11 and vulkan. In theory it's now possible to
support other vo_gpu backends, as well as backends that don't use the
vo_gpu code at all.

This also aims to get rid of the dumb mpv_get_sub_api() function. The
life cycle of the new mpv_render_context is a bit different from
mpv_opengl_cb_context, and you explicitly create/destroy the new
context, instead of calling init/uninit on an object returned by
mpv_get_sub_api().

In other to make the render API generic, it's annoyingly EGL style, and
requires you to pass in API-specific objects to generic functions. This
is to avoid explicit objects like the internal ra API has, because that
sounds more complicated and annoying for an API that's supposed to never
change.

The opengl_cb API will continue to exist for a bit longer, but
internally there are already a few tradeoffs, like reduced
thread-safety.

Mostly untested. Seems to work fine with mpc-qt.
2018-02-28 00:55:06 -08:00
Anton Kindestam fe23715876 context_drm_egl: Repair VT switching
The VT switcher was being set up, but it was being neither polled nor
interrupted.

Insert wait_events and wakeup functions based on those from vo_drm,
and add return early in drm_egl_swap_buffers if p->active isn't set.

This should get basic VT switching working, however there will likely
still be some random glitches. Switching between mpv and X11/weston is
unlikely to work satisfactorily until we can solve the problems with
drmSetMaster and drmDropMaster.
2018-02-26 23:56:13 -08:00
Anton Kindestam 3325c7a912 context_drm_egl: Introduce 30bpp support
This introduces the option --drm-format (currently used only by
context_drm_egl, vo_drm implementation is pending) which allows you to
pick between a xrgb8888 or a xrgb2101010 visual for --gpu-context=drm.

Requires a recent mesa (18.0.0_rc4 or later) to work.

This also fixes a bug when using --gpu-context=drm on a 30bpp-enabled
mesa (allow_rgb10_configs set to true). Previously it would've set up
an XRGB8888 format at the DRM/GBM level, while a 30bpp EGLConfig would
be picked, resulting in a garbled image.
2018-02-26 23:56:13 -08:00
Anton Kindestam bb07b22d42 egl_helpers: mpegl_cb can now signal an error condition
This can be used by client code that needs to fail when it cannot find
a suitable EGLConfig.
2018-02-26 23:56:13 -08:00
wm4 0dbad9503f vo_gpu: hwdec_drmprime_drm: cosmetic simplification
Coverity complained about the redundant init of hratio etc. - just
remove that and merge declaration/init of these variables. Also the
first double cast in each expression is unnecessary.
2018-02-16 22:04:15 -08:00