Remove WebM support (and deps libvpx and opus)

We've had many issues with WebM support and specifically the libvpx library
over the years, mostly due to its poor integration in Godot's buildsystem,
but without anyone really interested in improving this state.

With the new GDExtensions in Godot 4.0, we intend to move video decoding to
first-party extensions, and this would likely be done using something like
libvlc to expose more codecs.

Removing the `webm` module means we can remove libsimplewebm, libvpx and
opus, which we were only used for that purpose. Both libvpx and opus were
fairly complex pieces of the buildsystem, so this is a nice cleanup.

This also removes the compile-time dependency on `yasm`.

Fixes lots of compilation or non-working WebM issues which will be linked
in the PR.

1 files changed, 0 insertions, 74 deletions

diff --git a/thirdparty/opus/silk/resampler_down2.c b/thirdparty/opus/silk/resampler_down2.c
deleted file mode 100644
index cec3634640..0000000000
--- a/thirdparty/opus/silk/resampler_down2.c
+++ /dev/null
@@ -1,74 +0,0 @@
-/***********************************************************************
-Copyright (c) 2006-2011, Skype Limited. All rights reserved.
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions
-are met:
-- Redistributions of source code must retain the above copyright notice,
-this list of conditions and the following disclaimer.
-- Redistributions in binary form must reproduce the above copyright
-notice, this list of conditions and the following disclaimer in the
-documentation and/or other materials provided with the distribution.
-- Neither the name of Internet Society, IETF or IETF Trust, nor the
-names of specific contributors, may be used to endorse or promote
-products derived from this software without specific prior written
-permission.
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
-LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-POSSIBILITY OF SUCH DAMAGE.
-***********************************************************************/
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include "SigProc_FIX.h"
-#include "resampler_rom.h"
-
-/* Downsample by a factor 2 */
-void silk_resampler_down2(
-    opus_int32                  *S,                 /* I/O  State vector [ 2 ]                                          */
-    opus_int16                  *out,               /* O    Output signal [ floor(len/2) ]                              */
-    const opus_int16            *in,                /* I    Input signal [ len ]                                        */
-    opus_int32                  inLen               /* I    Number of input samples                                     */
-)
-{
-    opus_int32 k, len2 = silk_RSHIFT32( inLen, 1 );
-    opus_int32 in32, out32, Y, X;
-
-    silk_assert( silk_resampler_down2_0 > 0 );
-    silk_assert( silk_resampler_down2_1 < 0 );
-
-    /* Internal variables and state are in Q10 format */
-    for( k = 0; k < len2; k++ ) {
-        /* Convert to Q10 */
-        in32 = silk_LSHIFT( (opus_int32)in[ 2 * k ], 10 );
-
-        /* All-pass section for even input sample */
-        Y      = silk_SUB32( in32, S[ 0 ] );
-        X      = silk_SMLAWB( Y, Y, silk_resampler_down2_1 );
-        out32  = silk_ADD32( S[ 0 ], X );
-        S[ 0 ] = silk_ADD32( in32, X );
-
-        /* Convert to Q10 */
-        in32 = silk_LSHIFT( (opus_int32)in[ 2 * k + 1 ], 10 );
-
-        /* All-pass section for odd input sample, and add to output of previous section */
-        Y      = silk_SUB32( in32, S[ 1 ] );
-        X      = silk_SMULWB( Y, silk_resampler_down2_0 );
-        out32  = silk_ADD32( out32, S[ 1 ] );
-        out32  = silk_ADD32( out32, X );
-        S[ 1 ] = silk_ADD32( in32, X );
-
-        /* Add, convert back to int16 and store to output */
-        out[ k ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( out32, 11 ) );
-    }
-}
-