ref: ed82668431413cf8d5389a631cad56a6c4d2d6da
dir: /game/g_phys.c/
/*
Copyright (C) 1997-2001 Id Software, Inc.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <u.h>
#include <libc.h>
#include <stdio.h>
#include "../q_shared.h"
/*
pushmove objects do not obey gravity, and do not interact with each other or trigger fields, but block normal movement and push normal objects when they move.
onground is set for toss objects when they come to a complete rest. it is set for steping or walking objects
doors, plats, etc are SOLID_BSP, and MOVETYPE_PUSH
bonus items are SOLID_TRIGGER touch, and MOVETYPE_TOSS
corpses are SOLID_NOT and MOVETYPE_TOSS
crates are SOLID_BBOX and MOVETYPE_TOSS
walking monsters are SOLID_SLIDEBOX and MOVETYPE_STEP
flying/floating monsters are SOLID_SLIDEBOX and MOVETYPE_FLY
solid_edge items only clip against bsp models.
*/
/*
============
SV_TestEntityPosition
============
*/
edict_t *SV_TestEntityPosition (edict_t *ent)
{
trace_t trace;
int mask;
if (ent->clipmask)
mask = ent->clipmask;
else
mask = MASK_SOLID;
trace = gi.trace (ent->s.origin, ent->mins, ent->maxs, ent->s.origin, ent, mask);
if (trace.startsolid)
return g_edicts;
return NULL;
}
/*
================
SV_CheckVelocity
================
*/
void SV_CheckVelocity (edict_t *ent)
{
int i;
//
// bound velocity
//
for (i=0 ; i<3 ; i++)
{
if (ent->velocity[i] > sv_maxvelocity->value)
ent->velocity[i] = sv_maxvelocity->value;
else if (ent->velocity[i] < -sv_maxvelocity->value)
ent->velocity[i] = -sv_maxvelocity->value;
}
}
/*
=============
SV_RunThink
Runs thinking code for this frame if necessary
=============
*/
qboolean SV_RunThink (edict_t *ent)
{
float thinktime;
thinktime = ent->nextthink;
if (thinktime <= 0)
return true;
if (thinktime > level.time+0.001)
return true;
ent->nextthink = 0;
if (!ent->think)
gi.error ("NULL ent->think");
ent->think (ent);
return false;
}
/*
==================
SV_Impact
Two entities have touched, so run their touch functions
==================
*/
void SV_Impact (edict_t *e1, trace_t *trace)
{
edict_t *e2;
// cplane_t backplane;
e2 = trace->ent;
if (e1->touch && e1->solid != SOLID_NOT)
e1->touch (e1, e2, &trace->plane, trace->surface);
if (e2->touch && e2->solid != SOLID_NOT)
e2->touch (e2, e1, NULL, NULL);
}
/*
==================
ClipVelocity
Slide off of the impacting object
returns the blocked flags (1 = floor, 2 = step / wall)
==================
*/
#define STOP_EPSILON 0.1
int ClipVelocity (vec3_t in, vec3_t normal, vec3_t out, float overbounce)
{
float backoff;
float change;
int i, blocked;
blocked = 0;
if (normal[2] > 0)
blocked |= 1; // floor
if (!normal[2])
blocked |= 2; // step
backoff = DotProduct (in, normal) * overbounce;
for (i=0 ; i<3 ; i++)
{
change = normal[i]*backoff;
out[i] = in[i] - change;
if (out[i] > -STOP_EPSILON && out[i] < STOP_EPSILON)
out[i] = 0;
}
return blocked;
}
/*
============
SV_FlyMove
The basic solid body movement clip that slides along multiple planes
Returns the clipflags if the velocity was modified (hit something solid)
1 = floor
2 = wall / step
4 = dead stop
============
*/
#define MAX_CLIP_PLANES 5
int SV_FlyMove (edict_t *ent, float time, int mask)
{
edict_t *hit;
int bumpcount, numbumps;
vec3_t dir;
float d;
int numplanes;
vec3_t planes[MAX_CLIP_PLANES];
vec3_t primal_velocity, original_velocity, new_velocity;
int i, j;
trace_t trace;
vec3_t end;
float time_left;
int blocked;
numbumps = 4;
blocked = 0;
VectorCopy (ent->velocity, original_velocity);
VectorCopy (ent->velocity, primal_velocity);
numplanes = 0;
time_left = time;
ent->groundentity = NULL;
for (bumpcount=0 ; bumpcount<numbumps ; bumpcount++)
{
for (i=0 ; i<3 ; i++)
end[i] = ent->s.origin[i] + time_left * ent->velocity[i];
trace = gi.trace (ent->s.origin, ent->mins, ent->maxs, end, ent, mask);
if (trace.allsolid)
{ // entity is trapped in another solid
VectorCopy (vec3_origin, ent->velocity);
return 3;
}
if (trace.fraction > 0)
{ // actually covered some distance
VectorCopy (trace.endpos, ent->s.origin);
VectorCopy (ent->velocity, original_velocity);
numplanes = 0;
}
if (trace.fraction == 1)
break; // moved the entire distance
hit = trace.ent;
if (trace.plane.normal[2] > 0.7)
{
blocked |= 1; // floor
if ( hit->solid == SOLID_BSP)
{
ent->groundentity = hit;
ent->groundentity_linkcount = hit->linkcount;
}
}
if (!trace.plane.normal[2])
{
blocked |= 2; // step
}
//
// run the impact function
//
SV_Impact (ent, &trace);
if (!ent->inuse)
break; // removed by the impact function
time_left -= time_left * trace.fraction;
// cliped to another plane
if (numplanes >= MAX_CLIP_PLANES)
{ // this shouldn't really happen
VectorCopy (vec3_origin, ent->velocity);
return 3;
}
VectorCopy (trace.plane.normal, planes[numplanes]);
numplanes++;
//
// modify original_velocity so it parallels all of the clip planes
//
for (i=0 ; i<numplanes ; i++)
{
ClipVelocity (original_velocity, planes[i], new_velocity, 1);
for (j=0 ; j<numplanes ; j++)
if ((j != i) && !VectorCompare (planes[i], planes[j]))
{
if (DotProduct (new_velocity, planes[j]) < 0)
break; // not ok
}
if (j == numplanes)
break;
}
if (i != numplanes)
{ // go along this plane
VectorCopy (new_velocity, ent->velocity);
}
else
{ // go along the crease
if (numplanes != 2)
{
// gi.dprintf ("clip velocity, numplanes == %i\n",numplanes);
VectorCopy (vec3_origin, ent->velocity);
return 7;
}
CrossProduct (planes[0], planes[1], dir);
d = DotProduct (dir, ent->velocity);
VectorScale (dir, d, ent->velocity);
}
//
// if original velocity is against the original velocity, stop dead
// to avoid tiny occilations in sloping corners
//
if (DotProduct (ent->velocity, primal_velocity) <= 0)
{
VectorCopy (vec3_origin, ent->velocity);
return blocked;
}
}
return blocked;
}
/*
============
SV_AddGravity
============
*/
void SV_AddGravity (edict_t *ent)
{
ent->velocity[2] -= ent->gravity * sv_gravity->value * FRAMETIME;
}
/*
===============================================================================
PUSHMOVE
===============================================================================
*/
/*
============
SV_PushEntity
Does not change the entities velocity at all
============
*/
trace_t SV_PushEntity (edict_t *ent, vec3_t push)
{
trace_t trace;
vec3_t start;
vec3_t end;
int mask;
VectorCopy (ent->s.origin, start);
VectorAdd (start, push, end);
retry:
if (ent->clipmask)
mask = ent->clipmask;
else
mask = MASK_SOLID;
trace = gi.trace (start, ent->mins, ent->maxs, end, ent, mask);
VectorCopy (trace.endpos, ent->s.origin);
gi.linkentity (ent);
if (trace.fraction != 1.0)
{
SV_Impact (ent, &trace);
// if the pushed entity went away and the pusher is still there
if (!trace.ent->inuse && ent->inuse)
{
// move the pusher back and try again
VectorCopy (start, ent->s.origin);
gi.linkentity (ent);
goto retry;
}
}
if (ent->inuse)
G_TouchTriggers (ent);
return trace;
}
typedef struct
{
edict_t *ent;
vec3_t origin;
vec3_t angles;
float deltayaw;
} pushed_t;
pushed_t pushed[MAX_EDICTS], *pushed_p;
edict_t *obstacle;
/*
============
SV_Push
Objects need to be moved back on a failed push,
otherwise riders would continue to slide.
============
*/
qboolean SV_Push (edict_t *pusher, vec3_t move, vec3_t amove)
{
int i, e;
edict_t *check, *block;
vec3_t mins, maxs;
pushed_t *p;
vec3_t org, org2, move2, forward, right, up;
// clamp the move to 1/8 units, so the position will
// be accurate for client side prediction
for (i=0 ; i<3 ; i++)
{
float temp;
temp = move[i]*8.0;
if (temp > 0.0)
temp += 0.5;
else
temp -= 0.5;
move[i] = 0.125 * (int)temp;
}
// find the bounding box
for (i=0 ; i<3 ; i++)
{
mins[i] = pusher->absmin[i] + move[i];
maxs[i] = pusher->absmax[i] + move[i];
}
// we need this for pushing things later
VectorSubtract (vec3_origin, amove, org);
AngleVectors (org, forward, right, up);
// save the pusher's original position
pushed_p->ent = pusher;
VectorCopy (pusher->s.origin, pushed_p->origin);
VectorCopy (pusher->s.angles, pushed_p->angles);
if (pusher->client)
pushed_p->deltayaw = pusher->client->ps.pmove.delta_angles[YAW];
pushed_p++;
// move the pusher to it's final position
VectorAdd (pusher->s.origin, move, pusher->s.origin);
VectorAdd (pusher->s.angles, amove, pusher->s.angles);
gi.linkentity (pusher);
// see if any solid entities are inside the final position
check = g_edicts+1;
for (e = 1; e < globals.num_edicts; e++, check++)
{
if (!check->inuse)
continue;
if (check->movetype == MOVETYPE_PUSH
|| check->movetype == MOVETYPE_STOP
|| check->movetype == MOVETYPE_NONE
|| check->movetype == MOVETYPE_NOCLIP)
continue;
if (!check->area.prev)
continue; // not linked in anywhere
// if the entity is standing on the pusher, it will definitely be moved
if (check->groundentity != pusher)
{
// see if the ent needs to be tested
if ( check->absmin[0] >= maxs[0]
|| check->absmin[1] >= maxs[1]
|| check->absmin[2] >= maxs[2]
|| check->absmax[0] <= mins[0]
|| check->absmax[1] <= mins[1]
|| check->absmax[2] <= mins[2] )
continue;
// see if the ent's bbox is inside the pusher's final position
if (!SV_TestEntityPosition (check))
continue;
}
if ((pusher->movetype == MOVETYPE_PUSH) || (check->groundentity == pusher))
{
// move this entity
pushed_p->ent = check;
VectorCopy (check->s.origin, pushed_p->origin);
VectorCopy (check->s.angles, pushed_p->angles);
pushed_p++;
// try moving the contacted entity
VectorAdd (check->s.origin, move, check->s.origin);
if (check->client)
{ // FIXME: doesn't rotate monsters?
check->client->ps.pmove.delta_angles[YAW] += amove[YAW];
}
// figure movement due to the pusher's amove
VectorSubtract (check->s.origin, pusher->s.origin, org);
org2[0] = DotProduct (org, forward);
org2[1] = -DotProduct (org, right);
org2[2] = DotProduct (org, up);
VectorSubtract (org2, org, move2);
VectorAdd (check->s.origin, move2, check->s.origin);
// may have pushed them off an edge
if (check->groundentity != pusher)
check->groundentity = NULL;
block = SV_TestEntityPosition (check);
if (!block)
{ // pushed ok
gi.linkentity (check);
// impact?
continue;
}
// if it is ok to leave in the old position, do it
// this is only relevent for riding entities, not pushed
// FIXME: this doesn't acount for rotation
VectorSubtract (check->s.origin, move, check->s.origin);
block = SV_TestEntityPosition (check);
if (!block)
{
pushed_p--;
continue;
}
}
// save off the obstacle so we can call the block function
obstacle = check;
// move back any entities we already moved
// go backwards, so if the same entity was pushed
// twice, it goes back to the original position
for (p=pushed_p-1 ; p>=pushed ; p--)
{
VectorCopy (p->origin, p->ent->s.origin);
VectorCopy (p->angles, p->ent->s.angles);
if (p->ent->client)
{
p->ent->client->ps.pmove.delta_angles[YAW] = p->deltayaw;
}
gi.linkentity (p->ent);
}
return false;
}
//FIXME: is there a better way to handle this?
// see if anything we moved has touched a trigger
for (p=pushed_p-1 ; p>=pushed ; p--)
G_TouchTriggers (p->ent);
return true;
}
/*
================
SV_Physics_Pusher
Bmodel objects don't interact with each other, but
push all box objects
================
*/
void SV_Physics_Pusher (edict_t *ent)
{
vec3_t move, amove;
edict_t *part, *mv;
// if not a team captain, so movement will be handled elsewhere
if ( ent->flags & FL_TEAMSLAVE)
return;
// make sure all team slaves can move before commiting
// any moves or calling any think functions
// if the move is blocked, all moved objects will be backed out
//retry:
pushed_p = pushed;
for (part = ent ; part ; part=part->teamchain)
{
if (part->velocity[0] || part->velocity[1] || part->velocity[2] ||
part->avelocity[0] || part->avelocity[1] || part->avelocity[2]
)
{ // object is moving
VectorScale (part->velocity, FRAMETIME, move);
VectorScale (part->avelocity, FRAMETIME, amove);
if (!SV_Push (part, move, amove))
break; // move was blocked
}
}
if (pushed_p > &pushed[MAX_EDICTS])
gi.error (ERR_FATAL, "pushed_p > &pushed[MAX_EDICTS], memory corrupted");
if (part)
{
// the move failed, bump all nextthink times and back out moves
for (mv = ent ; mv ; mv=mv->teamchain)
{
if (mv->nextthink > 0)
mv->nextthink += FRAMETIME;
}
// if the pusher has a "blocked" function, call it
// otherwise, just stay in place until the obstacle is gone
if (part->blocked)
part->blocked (part, obstacle);
/*
// if the pushed entity went away and the pusher is still there
if (!obstacle->inuse && part->inuse)
goto retry;
*/
}
else
{
// the move succeeded, so call all think functions
for (part = ent ; part ; part=part->teamchain)
{
SV_RunThink (part);
}
}
}
//==================================================================
/*
=============
SV_Physics_None
Non moving objects can only think
=============
*/
void SV_Physics_None (edict_t *ent)
{
// regular thinking
SV_RunThink (ent);
}
/*
=============
SV_Physics_Noclip
A moving object that doesn't obey physics
=============
*/
void SV_Physics_Noclip (edict_t *ent)
{
// regular thinking
if (!SV_RunThink (ent))
return;
VectorMA (ent->s.angles, FRAMETIME, ent->avelocity, ent->s.angles);
VectorMA (ent->s.origin, FRAMETIME, ent->velocity, ent->s.origin);
gi.linkentity (ent);
}
/*
==============================================================================
TOSS / BOUNCE
==============================================================================
*/
/*
=============
SV_Physics_Toss
Toss, bounce, and fly movement. When onground, do nothing.
=============
*/
void SV_Physics_Toss (edict_t *ent)
{
trace_t trace;
vec3_t move;
float backoff;
edict_t *slave;
qboolean wasinwater;
qboolean isinwater;
vec3_t old_origin;
// regular thinking
SV_RunThink (ent);
// if not a team captain, so movement will be handled elsewhere
if ( ent->flags & FL_TEAMSLAVE)
return;
if (ent->velocity[2] > 0)
ent->groundentity = NULL;
// check for the groundentity going away
if (ent->groundentity)
if (!ent->groundentity->inuse)
ent->groundentity = NULL;
// if onground, return without moving
if ( ent->groundentity )
return;
VectorCopy (ent->s.origin, old_origin);
SV_CheckVelocity (ent);
// add gravity
if (ent->movetype != MOVETYPE_FLY
&& ent->movetype != MOVETYPE_FLYMISSILE)
SV_AddGravity (ent);
// move angles
VectorMA (ent->s.angles, FRAMETIME, ent->avelocity, ent->s.angles);
// move origin
VectorScale (ent->velocity, FRAMETIME, move);
trace = SV_PushEntity (ent, move);
if (!ent->inuse)
return;
if (trace.fraction < 1)
{
if (ent->movetype == MOVETYPE_BOUNCE)
backoff = 1.5;
else
backoff = 1;
ClipVelocity (ent->velocity, trace.plane.normal, ent->velocity, backoff);
// stop if on ground
if (trace.plane.normal[2] > 0.7)
{
if (ent->velocity[2] < 60 || ent->movetype != MOVETYPE_BOUNCE )
{
ent->groundentity = trace.ent;
ent->groundentity_linkcount = trace.ent->linkcount;
VectorCopy (vec3_origin, ent->velocity);
VectorCopy (vec3_origin, ent->avelocity);
}
}
// if (ent->touch)
// ent->touch (ent, trace.ent, &trace.plane, trace.surface);
}
// check for water transition
wasinwater = (ent->watertype & MASK_WATER);
ent->watertype = gi.pointcontents (ent->s.origin);
isinwater = ent->watertype & MASK_WATER;
if (isinwater)
ent->waterlevel = 1;
else
ent->waterlevel = 0;
if (!wasinwater && isinwater)
gi.positioned_sound (old_origin, g_edicts, CHAN_AUTO, gi.soundindex("misc/h2ohit1.wav"), 1, 1, 0);
else if (wasinwater && !isinwater)
gi.positioned_sound (ent->s.origin, g_edicts, CHAN_AUTO, gi.soundindex("misc/h2ohit1.wav"), 1, 1, 0);
// move teamslaves
for (slave = ent->teamchain; slave; slave = slave->teamchain)
{
VectorCopy (ent->s.origin, slave->s.origin);
gi.linkentity (slave);
}
}
/*
===============================================================================
STEPPING MOVEMENT
===============================================================================
*/
/*
=============
SV_Physics_Step
Monsters freefall when they don't have a ground entity, otherwise
all movement is done with discrete steps.
This is also used for objects that have become still on the ground, but
will fall if the floor is pulled out from under them.
FIXME: is this true?
=============
*/
//FIXME: hacked in for E3 demo
#define sv_stopspeed 100
#define sv_friction 6
#define sv_waterfriction 1
void SV_AddRotationalFriction (edict_t *ent)
{
int n;
float adjustment;
VectorMA (ent->s.angles, FRAMETIME, ent->avelocity, ent->s.angles);
adjustment = FRAMETIME * sv_stopspeed * sv_friction;
for (n = 0; n < 3; n++)
{
if (ent->avelocity[n] > 0)
{
ent->avelocity[n] -= adjustment;
if (ent->avelocity[n] < 0)
ent->avelocity[n] = 0;
}
else
{
ent->avelocity[n] += adjustment;
if (ent->avelocity[n] > 0)
ent->avelocity[n] = 0;
}
}
}
void SV_Physics_Step (edict_t *ent)
{
qboolean wasonground;
qboolean hitsound = false;
float *vel;
float speed, newspeed, control;
float friction;
edict_t *groundentity;
int mask;
// airborn monsters should always check for ground
if (!ent->groundentity)
M_CheckGround (ent);
groundentity = ent->groundentity;
SV_CheckVelocity (ent);
if (groundentity)
wasonground = true;
else
wasonground = false;
if (ent->avelocity[0] || ent->avelocity[1] || ent->avelocity[2])
SV_AddRotationalFriction (ent);
// add gravity except:
// flying monsters
// swimming monsters who are in the water
if (! wasonground)
if (!(ent->flags & FL_FLY))
if (!((ent->flags & FL_SWIM) && (ent->waterlevel > 2)))
{
if (ent->velocity[2] < sv_gravity->value*-0.1)
hitsound = true;
if (ent->waterlevel == 0)
SV_AddGravity (ent);
}
// friction for flying monsters that have been given vertical velocity
if ((ent->flags & FL_FLY) && (ent->velocity[2] != 0))
{
speed = fabs(ent->velocity[2]);
control = speed < sv_stopspeed ? sv_stopspeed : speed;
friction = sv_friction/3;
newspeed = speed - (FRAMETIME * control * friction);
if (newspeed < 0)
newspeed = 0;
newspeed /= speed;
ent->velocity[2] *= newspeed;
}
// friction for flying monsters that have been given vertical velocity
if ((ent->flags & FL_SWIM) && (ent->velocity[2] != 0))
{
speed = fabs(ent->velocity[2]);
control = speed < sv_stopspeed ? sv_stopspeed : speed;
newspeed = speed - (FRAMETIME * control * sv_waterfriction * ent->waterlevel);
if (newspeed < 0)
newspeed = 0;
newspeed /= speed;
ent->velocity[2] *= newspeed;
}
if (ent->velocity[2] || ent->velocity[1] || ent->velocity[0])
{
// apply friction
// let dead monsters who aren't completely onground slide
if ((wasonground) || (ent->flags & (FL_SWIM|FL_FLY)))
if (!(ent->health <= 0.0 && !M_CheckBottom(ent)))
{
vel = ent->velocity;
speed = sqrt(vel[0]*vel[0] +vel[1]*vel[1]);
if (speed)
{
friction = sv_friction;
control = speed < sv_stopspeed ? sv_stopspeed : speed;
newspeed = speed - FRAMETIME*control*friction;
if (newspeed < 0)
newspeed = 0;
newspeed /= speed;
vel[0] *= newspeed;
vel[1] *= newspeed;
}
}
if (ent->svflags & SVF_MONSTER)
mask = MASK_MONSTERSOLID;
else
mask = MASK_SOLID;
SV_FlyMove (ent, FRAMETIME, mask);
gi.linkentity (ent);
G_TouchTriggers (ent);
if (!ent->inuse)
return;
if (ent->groundentity)
if (!wasonground)
if (hitsound)
gi.sound (ent, 0, gi.soundindex("world/land.wav"), 1, 1, 0);
}
// regular thinking
SV_RunThink (ent);
}
//============================================================================
/*
================
G_RunEntity
================
*/
void G_RunEntity (edict_t *ent)
{
if (ent->prethink)
ent->prethink (ent);
switch ( (int)ent->movetype)
{
case MOVETYPE_PUSH:
case MOVETYPE_STOP:
SV_Physics_Pusher (ent);
break;
case MOVETYPE_NONE:
SV_Physics_None (ent);
break;
case MOVETYPE_NOCLIP:
SV_Physics_Noclip (ent);
break;
case MOVETYPE_STEP:
SV_Physics_Step (ent);
break;
case MOVETYPE_TOSS:
case MOVETYPE_BOUNCE:
case MOVETYPE_FLY:
case MOVETYPE_FLYMISSILE:
SV_Physics_Toss (ent);
break;
default:
gi.error ("SV_Physics: bad movetype %i", (int)ent->movetype);
}
}