Re: dsound: Fix angle to sound source calculation.

Forwarding on to wine-devel, Stas, and Ruslan from Bug 38041. Any thoughts on the coning breakage, Stas? Andrew On Mon, Mar 23, 2015 at 09:52:32PM +0000, Mark Harmstone wrote: > Hi, > > I've had a play with it, and yes, I think he's right. It seems to be a > lot more robust than my code. One thing though that I think he's > overlooked is that he changes the behaviour of AngleBetweenVectorsRad, > which is called by AngleBetweenVectorsDeg and thus the coning code - > I think this patch will probably break that. > > I've not tested it yet, but there's a chance this patch might fix > bug 38041. > > Mark > > On 23/03/15 14:39, Andrew Eikum wrote: > > This seems sane to me, but I never had a good grasp on this to begin > > with. Does it look OK to you, Mark? > > > > Andrew > > > > On Sun, Mar 22, 2015 at 08:59:15PM +0300, Стас Цымбалов wrote: > >> This patch fixes incorrect sound positioning in dsound. > >> As of now, angle to sound source is calculated as angle between > >> vDistance and vOrientFront. > >> This leads to incorrect results for all sources that are not in the > >> same plane as speakers. > >> In extreme case: for sources directly above or below origin, angle is > >> calculated to -90 degrees, and they are played in the left speaker. > >> > >> This patch changes angle calculation: angle to sound source is > >> calculated as angle between vDistance and plane given by vectors > >> vOrientFront and vOrientTop. > >> --- > >> dlls/dsound/sound3d.c | 25 ++++++++++++++----------- > >> 1 file changed, 14 insertions(+), 11 deletions(-) > > > >> From 1ebe3761b0d6acfca58cec17472336a05b7f2679 Mon Sep 17 00:00:00 2001 > >> From: Stas Cymbalov &lt;dummyunit(a)gmail.com&gt; > >> Date: Sun, 22 Mar 2015 18:22:49 +0300 > >> Subject: dsound: Fix angle to sound source calculation. > >> > >> --- > >> dlls/dsound/sound3d.c | 25 ++++++++++++++----------- > >> 1 file changed, 14 insertions(+), 11 deletions(-) > >> > >> diff --git a/dlls/dsound/sound3d.c b/dlls/dsound/sound3d.c > >> index 9a0226a..ffd4d45 100644 > >> --- a/dlls/dsound/sound3d.c > >> +++ b/dlls/dsound/sound3d.c > >> @@ -112,7 +112,6 @@ static inline D3DVALUE AngleBetweenVectorsRad (const D3DVECTOR *a, const D3DVECT > >> > >> cos = product/(la*lb); > >> angle = acos(cos); > >> - if (cos < 0.0f) { angle -= M_PI; } > >> TRACE("angle between (%f,%f,%f) and (%f,%f,%f) = %f radians (%f degrees)\n", a->x, a->y, a->z, b->x, > >> b->y, b->z, angle, RadToDeg(angle)); > >> return angle; > >> @@ -264,16 +263,20 @@ void DSOUND_Calc3DBuffer(IDirectSoundBufferImpl *dsb) > >> else > >> { > >> vLeft = VectorProduct(&dsb->device->ds3dl.vOrientFront, &dsb->device->ds3dl.vOrientTop); > >> - flAngle = AngleBetweenVectorsRad(&dsb->device->ds3dl.vOrientFront, &vDistance); > >> - flAngle2 = AngleBetweenVectorsRad(&vLeft, &vDistance); > >> - > >> - /* AngleBetweenVectorsRad performs a dot product, which gives us the cosine of the angle > >> - * between two vectors. Unfortunately, because cos(theta) = cos(-theta), we've no idea from > >> - * this whether the sound is to our left or to our right. We have to perform another dot > >> - * product, with a vector at right angles to the initial one, to get the correct angle. > >> - * The angle should be between -180 degrees and 180 degrees. */ > >> - if (flAngle < 0.0f) { flAngle += M_PI; } > >> - if (flAngle2 > 0.0f) { flAngle = -flAngle; } > >> + /* To calculate angle to sound source we need to: > >> + * 1) Get angle between vDistance and a plane on which angle to sound source should be 0. > >> + * Such a plane is given by vectors vOrientFront and vOrientTop, and angle between vector > >> + * and a plane equals to M_PI_2 - angle between vector and normal to this plane (vLeft in this case). > >> + * 2) Determine if the source is behind or in front of us by calculating angle between vDistance > >> + * and vOrientFront. > >> + */ > >> + flAngle = AngleBetweenVectorsRad(&vLeft, &vDistance); > >> + flAngle2 = AngleBetweenVectorsRad(&dsb->device->ds3dl.vOrientFront, &vDistance); > >> + if (flAngle2 > M_PI_2) > >> + flAngle = -flAngle; > >> + flAngle -= M_PI_2; > >> + if (flAngle < -M_PI) > >> + flAngle += 2*M_PI; > >> } > >> TRACE("panning: Angle = %f rad, lPan = %d\n", flAngle, dsb->volpan.lPan); > >> > >> -- > >> 2.0.5 > >> > > > >> > > >