ref: 710f779fdacf57a6311c62c6e29a5e8e18576c3f
dir: /game/m_move.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.
*/
// m_move.c -- monster movement
#include "g_local.h"
#define STEPSIZE 18
/*
=============
M_CheckBottom
Returns false if any part of the bottom of the entity is off an edge that
is not a staircase.
=============
*/
int c_yes, c_no;
qboolean M_CheckBottom (edict_t *ent)
{
vec3_t mins, maxs, start, stop;
trace_t trace;
int x, y;
float mid, bottom;
VectorAdd (ent->s.origin, ent->mins, mins);
VectorAdd (ent->s.origin, ent->maxs, maxs);
// if all of the points under the corners are solid world, don't bother
// with the tougher checks
// the corners must be within 16 of the midpoint
start[2] = mins[2] - 1;
for (x=0 ; x<=1 ; x++)
for (y=0 ; y<=1 ; y++)
{
start[0] = x ? maxs[0] : mins[0];
start[1] = y ? maxs[1] : mins[1];
if (gi.pointcontents (start) != CONTENTS_SOLID)
goto realcheck;
}
c_yes++;
return true; // we got out easy
realcheck:
c_no++;
//
// check it for real...
//
start[2] = mins[2];
// the midpoint must be within 16 of the bottom
start[0] = stop[0] = (mins[0] + maxs[0])*0.5;
start[1] = stop[1] = (mins[1] + maxs[1])*0.5;
stop[2] = start[2] - 2*STEPSIZE;
trace = gi.trace (start, vec3_origin, vec3_origin, stop, ent, MASK_MONSTERSOLID);
if (trace.fraction == 1.0)
return false;
mid = bottom = trace.endpos[2];
// the corners must be within 16 of the midpoint
for (x=0 ; x<=1 ; x++)
for (y=0 ; y<=1 ; y++)
{
start[0] = stop[0] = x ? maxs[0] : mins[0];
start[1] = stop[1] = y ? maxs[1] : mins[1];
trace = gi.trace (start, vec3_origin, vec3_origin, stop, ent, MASK_MONSTERSOLID);
if (trace.fraction != 1.0 && trace.endpos[2] > bottom)
bottom = trace.endpos[2];
if (trace.fraction == 1.0 || mid - trace.endpos[2] > STEPSIZE)
return false;
}
c_yes++;
return true;
}
/*
=============
SV_movestep
Called by monster program code.
The move will be adjusted for slopes and stairs, but if the move isn't
possible, no move is done, false is returned, and
pr_global_struct->trace_normal is set to the normal of the blocking wall
=============
*/
//FIXME since we need to test end position contents here, can we avoid doing
//it again later in catagorize position?
qboolean SV_movestep (edict_t *ent, vec3_t move, qboolean relink)
{
float dz;
vec3_t oldorg, neworg, end;
trace_t trace;
int i;
float stepsize;
vec3_t test;
int contents;
// try the move
VectorCopy (ent->s.origin, oldorg);
VectorAdd (ent->s.origin, move, neworg);
// flying monsters don't step up
if ( ent->flags & (FL_SWIM | FL_FLY) )
{
// try one move with vertical motion, then one without
for (i=0 ; i<2 ; i++)
{
VectorAdd (ent->s.origin, move, neworg);
if (i == 0 && ent->enemy)
{
if (!ent->goalentity)
ent->goalentity = ent->enemy;
dz = ent->s.origin[2] - ent->goalentity->s.origin[2];
if (ent->goalentity->client)
{
if (dz > 40)
neworg[2] -= 8;
if (!((ent->flags & FL_SWIM) && (ent->waterlevel < 2)))
if (dz < 30)
neworg[2] += 8;
}
else
{
if (dz > 8)
neworg[2] -= 8;
else if (dz > 0)
neworg[2] -= dz;
else if (dz < -8)
neworg[2] += 8;
else
neworg[2] += dz;
}
}
trace = gi.trace (ent->s.origin, ent->mins, ent->maxs, neworg, ent, MASK_MONSTERSOLID);
// fly monsters don't enter water voluntarily
if (ent->flags & FL_FLY)
{
if (!ent->waterlevel)
{
test[0] = trace.endpos[0];
test[1] = trace.endpos[1];
test[2] = trace.endpos[2] + ent->mins[2] + 1;
contents = gi.pointcontents(test);
if (contents & MASK_WATER)
return false;
}
}
// swim monsters don't exit water voluntarily
if (ent->flags & FL_SWIM)
{
if (ent->waterlevel < 2)
{
test[0] = trace.endpos[0];
test[1] = trace.endpos[1];
test[2] = trace.endpos[2] + ent->mins[2] + 1;
contents = gi.pointcontents(test);
if (!(contents & MASK_WATER))
return false;
}
}
if (trace.fraction == 1)
{
VectorCopy (trace.endpos, ent->s.origin);
if (relink)
{
gi.linkentity (ent);
G_TouchTriggers (ent);
}
return true;
}
if (!ent->enemy)
break;
}
return false;
}
// push down from a step height above the wished position
if (!(ent->monsterinfo.aiflags & AI_NOSTEP))
stepsize = STEPSIZE;
else
stepsize = 1;
neworg[2] += stepsize;
VectorCopy (neworg, end);
end[2] -= stepsize*2;
trace = gi.trace (neworg, ent->mins, ent->maxs, end, ent, MASK_MONSTERSOLID);
if (trace.allsolid)
return false;
if (trace.startsolid)
{
neworg[2] -= stepsize;
trace = gi.trace (neworg, ent->mins, ent->maxs, end, ent, MASK_MONSTERSOLID);
if (trace.allsolid || trace.startsolid)
return false;
}
// don't go in to water
if (ent->waterlevel == 0)
{
test[0] = trace.endpos[0];
test[1] = trace.endpos[1];
test[2] = trace.endpos[2] + ent->mins[2] + 1;
contents = gi.pointcontents(test);
if (contents & MASK_WATER)
return false;
}
if (trace.fraction == 1)
{
// if monster had the ground pulled out, go ahead and fall
if ( ent->flags & FL_PARTIALGROUND )
{
VectorAdd (ent->s.origin, move, ent->s.origin);
if (relink)
{
gi.linkentity (ent);
G_TouchTriggers (ent);
}
ent->groundentity = NULL;
return true;
}
return false; // walked off an edge
}
// check point traces down for dangling corners
VectorCopy (trace.endpos, ent->s.origin);
if (!M_CheckBottom (ent))
{
if ( ent->flags & FL_PARTIALGROUND )
{ // entity had floor mostly pulled out from underneath it
// and is trying to correct
if (relink)
{
gi.linkentity (ent);
G_TouchTriggers (ent);
}
return true;
}
VectorCopy (oldorg, ent->s.origin);
return false;
}
if ( ent->flags & FL_PARTIALGROUND )
{
ent->flags &= ~FL_PARTIALGROUND;
}
ent->groundentity = trace.ent;
ent->groundentity_linkcount = trace.ent->linkcount;
// the move is ok
if (relink)
{
gi.linkentity (ent);
G_TouchTriggers (ent);
}
return true;
}
//============================================================================
/*
===============
M_ChangeYaw
===============
*/
void M_ChangeYaw (edict_t *ent)
{
float ideal;
float current;
float move;
float speed;
current = anglemod(ent->s.angles[YAW]);
ideal = ent->ideal_yaw;
if (current == ideal)
return;
move = ideal - current;
speed = ent->yaw_speed;
if (ideal > current)
{
if (move >= 180)
move = move - 360;
}
else
{
if (move <= -180)
move = move + 360;
}
if (move > 0)
{
if (move > speed)
move = speed;
}
else
{
if (move < -speed)
move = -speed;
}
ent->s.angles[YAW] = anglemod (current + move);
}
/*
======================
SV_StepDirection
Turns to the movement direction, and walks the current distance if
facing it.
======================
*/
qboolean SV_StepDirection (edict_t *ent, float yaw, float dist)
{
vec3_t move, oldorigin;
float delta;
ent->ideal_yaw = yaw;
M_ChangeYaw (ent);
yaw = yaw*M_PI*2 / 360;
move[0] = cos(yaw)*dist;
move[1] = sin(yaw)*dist;
move[2] = 0;
VectorCopy (ent->s.origin, oldorigin);
if (SV_movestep (ent, move, false))
{
delta = ent->s.angles[YAW] - ent->ideal_yaw;
if (delta > 45 && delta < 315)
{ // not turned far enough, so don't take the step
VectorCopy (oldorigin, ent->s.origin);
}
gi.linkentity (ent);
G_TouchTriggers (ent);
return true;
}
gi.linkentity (ent);
G_TouchTriggers (ent);
return false;
}
/*
======================
SV_FixCheckBottom
======================
*/
void SV_FixCheckBottom (edict_t *ent)
{
ent->flags |= FL_PARTIALGROUND;
}
/*
================
SV_NewChaseDir
================
*/
#define DI_NODIR -1
void SV_NewChaseDir (edict_t *actor, edict_t *enemy, float dist)
{
float deltax,deltay;
float d[3];
float tdir, olddir, turnaround;
//FIXME: how did we get here with no enemy
if (!enemy)
return;
olddir = anglemod( (int)(actor->ideal_yaw/45)*45 );
turnaround = anglemod(olddir - 180);
deltax = enemy->s.origin[0] - actor->s.origin[0];
deltay = enemy->s.origin[1] - actor->s.origin[1];
if (deltax>10)
d[1]= 0;
else if (deltax<-10)
d[1]= 180;
else
d[1]= DI_NODIR;
if (deltay<-10)
d[2]= 270;
else if (deltay>10)
d[2]= 90;
else
d[2]= DI_NODIR;
// try direct route
if (d[1] != DI_NODIR && d[2] != DI_NODIR)
{
if (d[1] == 0)
tdir = d[2] == 90 ? 45 : 315;
else
tdir = d[2] == 90 ? 135 : 215;
if (tdir != turnaround && SV_StepDirection(actor, tdir, dist))
return;
}
// try other directions
if ( ((rand()&3) & 1) || abs(deltay)>abs(deltax))
{
tdir=d[1];
d[1]=d[2];
d[2]=tdir;
}
if (d[1]!=DI_NODIR && d[1]!=turnaround
&& SV_StepDirection(actor, d[1], dist))
return;
if (d[2]!=DI_NODIR && d[2]!=turnaround
&& SV_StepDirection(actor, d[2], dist))
return;
/* there is no direct path to the player, so pick another direction */
if (olddir!=DI_NODIR && SV_StepDirection(actor, olddir, dist))
return;
if (rand()&1) /*randomly determine direction of search*/
{
for (tdir=0 ; tdir<=315 ; tdir += 45)
if (tdir!=turnaround && SV_StepDirection(actor, tdir, dist) )
return;
}
else
{
for (tdir=315 ; tdir >=0 ; tdir -= 45)
if (tdir!=turnaround && SV_StepDirection(actor, tdir, dist) )
return;
}
if (turnaround != DI_NODIR && SV_StepDirection(actor, turnaround, dist) )
return;
actor->ideal_yaw = olddir; // can't move
// if a bridge was pulled out from underneath a monster, it may not have
// a valid standing position at all
if (!M_CheckBottom (actor))
SV_FixCheckBottom (actor);
}
/*
======================
SV_CloseEnough
======================
*/
qboolean SV_CloseEnough (edict_t *ent, edict_t *goal, float dist)
{
int i;
for (i=0 ; i<3 ; i++)
{
if (goal->absmin[i] > ent->absmax[i] + dist)
return false;
if (goal->absmax[i] < ent->absmin[i] - dist)
return false;
}
return true;
}
/*
======================
M_MoveToGoal
======================
*/
void M_MoveToGoal (edict_t *ent, float dist)
{
edict_t *goal;
goal = ent->goalentity;
if (!ent->groundentity && !(ent->flags & (FL_FLY|FL_SWIM)))
return;
// if the next step hits the enemy, return immediately
if (ent->enemy && SV_CloseEnough (ent, ent->enemy, dist) )
return;
// bump around...
if ( (rand()&3)==1 || !SV_StepDirection (ent, ent->ideal_yaw, dist))
{
if (ent->inuse)
SV_NewChaseDir (ent, goal, dist);
}
}
/*
===============
M_walkmove
===============
*/
qboolean M_walkmove (edict_t *ent, float yaw, float dist)
{
vec3_t move;
if (!ent->groundentity && !(ent->flags & (FL_FLY|FL_SWIM)))
return false;
yaw = yaw*M_PI*2 / 360;
move[0] = cos(yaw)*dist;
move[1] = sin(yaw)*dist;
move[2] = 0;
return SV_movestep(ent, move, true);
}