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jDoom|jDoom64|jHeretic|WolfTC: Fixed a potential segfault in P_ApplyT…
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…orque.
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danij committed Jun 25, 2008
1 parent 27466bd commit 8f0f9ef
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Showing 4 changed files with 91 additions and 84 deletions.
9 changes: 6 additions & 3 deletions doomsday/plugins/jdoom/src/p_maputl.c
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Expand Up @@ -78,13 +78,16 @@ static boolean PIT_ApplyTorque(linedef_t *ld, void *data)
if(tmThing->player)
return true; // Skip players!

dx = P_GetFloatp(ld, DMU_DX);
dy = P_GetFloatp(ld, DMU_DY);

frontsec = P_GetPtrp(ld, DMU_FRONT_SECTOR);
backsec = P_GetPtrp(ld, DMU_BACK_SECTOR);

if(!frontsec || !backsec)
return true; // Shouldn't ever happen.

ffloor = P_GetFloatp(frontsec, DMU_FLOOR_HEIGHT);
bfloor = P_GetFloatp(backsec, DMU_FLOOR_HEIGHT);
dx = P_GetFloatp(ld, DMU_DX);
dy = P_GetFloatp(ld, DMU_DY);

// Lever-arm:
dist =
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12 changes: 7 additions & 5 deletions doomsday/plugins/jdoom64/src/p_maputl.c
View file
Expand Up @@ -72,20 +72,22 @@ static boolean PIT_ApplyTorque(linedef_t *ld, void *data)
mobj_t *mo = tmThing;
float dist;
sector_t *frontsec, *backsec;
float ffloor;
float bfloor;
float ffloor, bfloor;
float dx, dy;

if(tmThing->player)
return true; // Skip players!

dx = P_GetFloatp(ld, DMU_DX);
dy = P_GetFloatp(ld, DMU_DY);

frontsec = P_GetPtrp(ld, DMU_FRONT_SECTOR);
backsec = P_GetPtrp(ld, DMU_BACK_SECTOR);

if(!frontsec || !backsec)
return true; // Shouldn't ever happen.

ffloor = P_GetFloatp(frontsec, DMU_FLOOR_HEIGHT);
bfloor = P_GetFloatp(backsec, DMU_FLOOR_HEIGHT);
dx = P_GetFloatp(ld, DMU_DX);
dy = P_GetFloatp(ld, DMU_DY);

// Lever-arm:
dist =
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26 changes: 14 additions & 12 deletions doomsday/plugins/jheretic/src/p_maputl.c
View file
Expand Up @@ -71,23 +71,25 @@ extern mobj_t *tmThing;
*/
static boolean PIT_ApplyTorque(linedef_t *ld, void *data)
{
mobj_t *mo = tmThing;
float dist;
sector_t *frontsec, *backsec;
float ffloor;
float bfloor;
float dx, dy;
mobj_t *mo = tmThing;
float dist;
sector_t *frontsec, *backsec;
float ffloor, bfloor;
float dx, dy;

if(tmThing->player)
return true; // skip players!

dx = P_GetFloatp(ld, DMU_DX);
dy = P_GetFloatp(ld, DMU_DY);
return true; // Skip players!

frontsec = P_GetPtrp(ld, DMU_FRONT_SECTOR);
backsec = P_GetPtrp(ld, DMU_BACK_SECTOR);

if(!frontsec || !backsec)
return true; // Shouldn't ever happen.

ffloor = P_GetFloatp(frontsec, DMU_FLOOR_HEIGHT);
bfloor = P_GetFloatp(backsec, DMU_FLOOR_HEIGHT);
dx = P_GetFloatp(ld, DMU_DX);
dy = P_GetFloatp(ld, DMU_DY);

// Lever-arm:
dist =
Expand All @@ -101,11 +103,11 @@ static boolean PIT_ApplyTorque(linedef_t *ld, void *data)
{
// At this point, we know that the object straddles a two-sided
// linedef, and that the object's center of mass is above-ground.
float x = fabs(dx), y = fabs(dy);
float x = fabs(dx), y = fabs(dy);

if(y > x)
{
float tmp = x;
float tmp = x;
x = y;
y = tmp;
}
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128 changes: 64 additions & 64 deletions doomsday/plugins/wolftc/src/p_maputl.c
View file
Expand Up @@ -72,76 +72,77 @@ extern mobj_t *tmThing;
*/
static boolean PIT_ApplyTorque(linedef_t *ld, void *data)
{
mobj_t *mo = tmThing;
fixed_t dist;
sector_t *frontsec = P_GetPtrp(ld, DMU_FRONT_SECTOR);
sector_t *backsec = P_GetPtrp(ld, DMU_BACK_SECTOR);
fixed_t ffloor;
fixed_t bfloor;
fixed_t dx = P_GetFixedp(ld, DMU_DX);
fixed_t dy = P_GetFixedp(ld, DMU_DY);

ffloor = P_GetFixedp(frontsec, DMU_FLOOR_HEIGHT);
bfloor = P_GetFixedp(backsec, DMU_FLOOR_HEIGHT);
mobj_t *mo = tmThing;
float dist;
sector_t *frontsec, *backsec;
float ffloor, bfloor;
float dx, dy;

if(tmThing->player)
return true; // skip players!
return true; // Skip players!

dist = // lever arm
+(dx >> FRACBITS) * (mo->pos[VY] >> FRACBITS) -
(dy >> FRACBITS) * (mo->pos[VX] >> FRACBITS) -
(dx >> FRACBITS) * (P_GetFixedp(P_GetPtrp(ld, DMU_VERTEX0),
DMU_Y) >> FRACBITS) +
(dy >> FRACBITS) * (P_GetFixedp(P_GetPtrp(ld, DMU_VERTEX0),
DMU_X) >> FRACBITS);
frontsec = P_GetPtrp(ld, DMU_FRONT_SECTOR);
backsec = P_GetPtrp(ld, DMU_BACK_SECTOR);

if((dist < 0 && ffloor < mo->pos[VZ] && bfloor >= mo->pos[VZ]) ||
if(!frontsec || !backsec)
return true; // Shouldn't ever happen.

ffloor = P_GetFloatp(frontsec, DMU_FLOOR_HEIGHT);
bfloor = P_GetFloatp(backsec, DMU_FLOOR_HEIGHT);
dx = P_GetFloatp(ld, DMU_DX);
dy = P_GetFloatp(ld, DMU_DY);

// Lever-arm:
dist =
+dx * mo->pos[VY] -
dy * mo->pos[VX] -
dx * (P_GetFloatp(P_GetPtrp(ld, DMU_VERTEX0), DMU_Y)) +
dy * (P_GetFloatp(P_GetPtrp(ld, DMU_VERTEX0), DMU_X));

if((dist < 0 && ffloor < mo->pos[VZ] && bfloor >= mo->pos[VZ]) ||
(dist >= 0 && bfloor < mo->pos[VZ] && ffloor >= mo->pos[VZ]))
{
// At this point, we know that the object straddles a two-sided
// linedef, and that the object's center of mass is above-ground.

fixed_t x = abs(dx), y = abs(dy);
float x = fabs(dx), y = fabs(dy);

if(y > x)
{
fixed_t t = x;

float tmp = x;
x = y;
y = t;
y = tmp;
}

y = finesine[(tantoangle[FixedDiv(y, x) >> DBITS] +
ANG90) >> ANGLETOFINESHIFT];
y = FIX2FLT(finesine[(tantoangle[FLT2FIX(y / x) >> DBITS] +
ANG90) >> ANGLETOFINESHIFT]);

// Momentum is proportional to distance between the
// object's center of mass and the pivot linedef.
//
// It is scaled by 2^(OVERDRIVE - gear). When gear is
// increased, the momentum gradually decreases to 0 for
// the same amount of pseudotorque, so that oscillations
// are prevented, yet it has a chance to reach equilibrium.
/**
* Momentum is proportional to distance between the object's center
* of mass and the pivot linedef.
*
* It is scaled by 2^(OVERDRIVE - gear). When gear is increased, the
* momentum gradually decreases to 0 for the same amount of
* pseudotorque, so that oscillations are prevented, yet it has a
* chance to reach equilibrium.
*/

if(mo->gear < OVERDRIVE)
dist = FixedDiv(FixedMul(dist, y << -(mo->gear - OVERDRIVE)), x);
dist = (dist * FIX2FLT(FLT2FIX(y) << -(mo->gear - OVERDRIVE))) / x;
else
dist = FixedDiv(FixedMul(dist, y >> +(mo->gear - OVERDRIVE)), x);
dist = (dist * FIX2FLT(FLT2FIX(y) >> +(mo->gear - OVERDRIVE))) / x;

// Apply momentum away from the pivot linedef.
x = dy * dist;
y = dx * dist;

x = FixedMul(dy, dist);
y = FixedMul(dx, dist);

// Avoid moving too fast all of a sudden (step into "overdrive")

dist = FixedMul(x, x) + FixedMul(y, y);

while(dist > FRACUNIT * 4 && mo->gear < MAXGEAR)
// Avoid moving too fast all of a sudden (step into "overdrive").
dist = (x * x) + (y * y);
while(dist > 4 && mo->gear < MAXGEAR)
{
++mo->gear;
x >>= 1;
y >>= 1;
dist >>= 1;
x /= 2;
y /= 2;
dist /= 2;
}

mo->mom[MX] -= x;
Expand All @@ -151,44 +152,43 @@ static boolean PIT_ApplyTorque(linedef_t *ld, void *data)
return true;
}

/*
/**
* Applies "torque" to objects, based on all contacted linedefs.
* killough $dropoff_fix
*/
void P_ApplyTorque(mobj_t *mo)
{
// Remember the current state, for gear-change
int flags = mo->intFlags;
int flags = mo->intFlags;

// 2003-4-16 (jk): corpse sliding anomalies, made configurable
// Corpse sliding anomalies, made configurable.
if(!cfg.slidingCorpses)
return;

tmThing = mo;

// Use VALIDCOUNT to prevent checking the same line twice
// Use VALIDCOUNT to prevent checking the same line twice.
VALIDCOUNT++;

P_MobjLinesIterator(mo, PIT_ApplyTorque, 0);

// If any momentum, mark object as 'falling' using engine-internal flags
if(mo->mom[MX] | mo->mom[MY])
// If any momentum, mark object as 'falling' using engine-internal
// flags.
if(mo->mom[MX] != 0 || mo->mom[MY] != 0)
mo->intFlags |= MIF_FALLING;
else
// Clear the engine-internal flag indicating falling object.
mo->intFlags &= ~MIF_FALLING;

// If the object has been moving, step up the gear.
// This helps reach equilibrium and avoid oscillations.
//
// Doom has no concept of potential energy, much less
// of rotation, so we have to creatively simulate these
// systems somehow :)
/**
* If the object has been moving, step up the gear. This helps reach
* equilibrium and avoid oscillations.
*
* DOOM has no concept of potential energy, much less of rotation, so we
* have to creatively simulate these systems somehow :)
*/

// If not falling for a while, reset it to full strength
// If not falling for a while, reset it to full strength.
if(!((mo->intFlags | flags) & MIF_FALLING))
mo->gear = 0;
else if(mo->gear < MAXGEAR)
// Else if not at max gear, move up a gear
else if(mo->gear < MAXGEAR) // Else if not at max gear, move up a gear.
mo->gear++;
}

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