rpgxef/code/game/bg_slidemove.c
Walter Julius Hennecke a39565b783 Integrated RPG-X2 rpgxEF edition into the rpgxEF repo
... not quite content with where the project files lie but it is ok for
now.
... compiling works fine so far (only tested mingw32 right now)
2012-08-04 12:54:37 +02:00

319 lines
8 KiB
C

// Copyright (C) 1999-2000 Id Software, Inc.
//
// bg_slidemove.c -- part of bg_pmove functionality
#include "q_shared.h"
#include "bg_public.h"
#include "bg_local.h"
/*
input: origin, velocity, bounds, groundPlane, trace function
output: origin, velocity, impacts, stairup boolean
*/
/*
==================
PM_SlideMove
==================
*/
/**
* Returns qtrue if the velocity was clipped in some way
*/
#define MAX_CLIP_PLANES 5
qboolean PM_SlideMove( qboolean gravity ) {
int bumpcount, numbumps;
vec3_t dir;
float d;
int numplanes;
vec3_t planes[MAX_CLIP_PLANES];
vec3_t primal_velocity;
vec3_t clipVelocity;
int i, j, k;
trace_t trace;
vec3_t end;
float time_left;
float into;
vec3_t endVelocity;
vec3_t endClipVelocity;
playerState_t *ps = pm->ps;
numbumps = 4;
VectorCopy (ps->velocity, primal_velocity);
if ( gravity ) {
VectorCopy( ps->velocity, endVelocity );
endVelocity[2] -= ps->gravity * pml.frametime;
ps->velocity[2] = ( ps->velocity[2] + endVelocity[2] ) * 0.5;
primal_velocity[2] = endVelocity[2];
if ( pml.groundPlane ) {
// slide along the ground plane
PM_ClipVelocity (ps->velocity, pml.groundTrace.plane.normal,
ps->velocity, OVERCLIP );
}
}
time_left = pml.frametime;
// never turn against the ground plane
if ( pml.groundPlane ) {
numplanes = 1;
VectorCopy( pml.groundTrace.plane.normal, planes[0] );
} else {
numplanes = 0;
}
// never turn against original velocity
VectorNormalize2( ps->velocity, planes[numplanes] );
numplanes++;
for ( bumpcount=0 ; bumpcount < numbumps ; bumpcount++ ) {
// calculate position we are trying to move to
VectorMA( ps->origin, time_left, ps->velocity, end );
// see if we can make it there
pm->trace ( &trace, ps->origin, pm->mins, pm->maxs, end, ps->clientNum, pm->tracemask);
if (trace.allsolid) {
// entity is completely trapped in another solid
ps->velocity[2] = 0; // don't build up falling damage, but allow sideways acceleration
return qtrue;
}
if (trace.fraction > 0) {
// actually covered some distance
VectorCopy (trace.endpos, ps->origin);
}
if (trace.fraction == 1) {
break; // moved the entire distance
}
// save entity for contact
PM_AddTouchEnt( trace.entityNum );
time_left -= time_left * trace.fraction;
if (numplanes >= MAX_CLIP_PLANES) {
// this shouldn't really happen
VectorClear( ps->velocity );
return qtrue;
}
//
// if this is the same plane we hit before, nudge velocity
// out along it, which fixes some epsilon issues with
// non-axial planes
//
for ( i = 0 ; i < numplanes ; i++ ) {
if ( DotProduct( trace.plane.normal, planes[i] ) > 0.99 ) {
VectorAdd( trace.plane.normal, ps->velocity, ps->velocity );
break;
}
}
if ( i < numplanes ) {
continue;
}
VectorCopy (trace.plane.normal, planes[numplanes]);
numplanes++;
//
// modify velocity so it parallels all of the clip planes
//
// find a plane that it enters
for ( i = 0 ; i < numplanes ; i++ ) {
into = DotProduct( ps->velocity, planes[i] );
if ( into >= 0.1 ) {
continue; // move doesn't interact with the plane
}
// see how hard we are hitting things
if ( -into > pml.impactSpeed ) {
pml.impactSpeed = -into;
}
// slide along the plane
PM_ClipVelocity (ps->velocity, planes[i], clipVelocity, OVERCLIP );
// slide along the plane
PM_ClipVelocity (endVelocity, planes[i], endClipVelocity, OVERCLIP );
// see if there is a second plane that the new move enters
for ( j = 0 ; j < numplanes ; j++ ) {
if ( j == i ) {
continue;
}
if ( DotProduct( clipVelocity, planes[j] ) >= 0.1 ) {
continue; // move doesn't interact with the plane
}
// try clipping the move to the plane
PM_ClipVelocity( clipVelocity, planes[j], clipVelocity, OVERCLIP );
PM_ClipVelocity( endClipVelocity, planes[j], endClipVelocity, OVERCLIP );
// see if it goes back into the first clip plane
if ( DotProduct( clipVelocity, planes[i] ) >= 0 ) {
continue;
}
// slide the original velocity along the crease
CrossProduct (planes[i], planes[j], dir);
VectorNormalize( dir );
d = DotProduct( dir, ps->velocity );
VectorScale( dir, d, clipVelocity );
CrossProduct (planes[i], planes[j], dir);
VectorNormalize( dir );
d = DotProduct( dir, endVelocity );
VectorScale( dir, d, endClipVelocity );
// see if there is a third plane the the new move enters
for ( k = 0 ; k < numplanes ; k++ ) {
if ( k == i || k == j ) {
continue;
}
if ( DotProduct( clipVelocity, planes[k] ) >= 0.1 ) {
continue; // move doesn't interact with the plane
}
// stop dead at a tripple plane interaction
VectorClear( ps->velocity );
return qtrue;
}
}
// if we have fixed all interactions, try another move
VectorCopy( clipVelocity, ps->velocity );
VectorCopy( endClipVelocity, endVelocity );
break;
}
}
if ( gravity ) {
VectorCopy( endVelocity, ps->velocity );
}
// don't change velocity if in a timer (FIXME: is this correct?)
if ( ps->pm_time ) {
VectorCopy( primal_velocity, ps->velocity );
}
return ( bumpcount != 0 );
}
/*
==================
PM_StepSlideMove
==================
*/
void PM_StepSlideMove( qboolean gravity ) {
vec3_t start_o, start_v;
vec3_t down_o, down_v;
vec3_t slideMove, stepUpMove;
trace_t trace;
// float down_dist, up_dist;
// vec3_t delta, delta2;
vec3_t up, down;
playerState_t *ps = pm->ps;
VectorCopy (ps->origin, start_o);
VectorCopy (ps->velocity, start_v);
if ( PM_SlideMove( gravity ) == 0 ) {
return; // we got exactly where we wanted to go first try
}
VectorCopy(start_o, down);
down[2] -= STEPSIZE;
pm->trace (&trace, start_o, pm->mins, pm->maxs, down, ps->clientNum, pm->tracemask);
VectorSet(up, 0, 0, 1);
// never step up when you still have up velocity
if ( ps->velocity[2] > 0 && (trace.fraction == 1.0 ||
DotProduct(trace.plane.normal, up) < 0.7)) {
return;
}
VectorCopy (ps->origin, down_o);
VectorCopy (ps->velocity, down_v);
VectorCopy (start_o, up);
up[2] += STEPSIZE;
// test the player position if they were a stepheight higher
pm->trace (&trace, up, pm->mins, pm->maxs, up, ps->clientNum, pm->tracemask);
if ( trace.allsolid ) {
if ( pm->debugLevel ) {
Com_Printf("%i:bend can't step\n", c_pmove);
}
return; // can't step up
}
// try slidemove from this position
VectorCopy (up, ps->origin);
VectorCopy (start_v, ps->velocity);
PM_SlideMove( gravity );
//compare the initial slidemove and this slidemove from a step up position
VectorSubtract( down_o, start_o, slideMove );
VectorSubtract( trace.endpos, ps->origin, stepUpMove );
if ( fabs(stepUpMove[0]) < 0.1 && fabs(stepUpMove[1]) < 0.1 && VectorLengthSquared( slideMove ) > VectorLengthSquared( stepUpMove ) )
{
//slideMove was better, use it
VectorCopy (down_o, ps->origin);
VectorCopy (down_v, ps->velocity);
}
else
{
// push down the final amount
VectorCopy (ps->origin, down);
down[2] -= STEPSIZE;
pm->trace (&trace, ps->origin, pm->mins, pm->maxs, down, ps->clientNum, pm->tracemask);
if ( !trace.allsolid ) {
VectorCopy (trace.endpos, ps->origin);
}
if ( trace.fraction < 1.0 ) {
PM_ClipVelocity( ps->velocity, trace.plane.normal, ps->velocity, OVERCLIP );
}
}
#if 0
// if the down trace can trace back to the original position directly, don't step
pm->trace( &trace, ps->origin, pm->mins, pm->maxs, start_o, ps->clientNum, pm->tracemask);
if ( trace.fraction == 1.0 ) {
// use the original move
VectorCopy (down_o, ps->origin);
VectorCopy (down_v, ps->velocity);
if ( pm->debugLevel ) {
Com_Printf("%i:bend\n", c_pmove);
}
} else
#endif
{
// use the step move
float delta;
delta = ps->origin[2] - start_o[2];
if ( delta > 2 ) {
if ( delta < 7 ) {
PM_AddEvent( EV_STEP_4 );
} else if ( delta < 11 ) {
PM_AddEvent( EV_STEP_8 );
} else if ( delta < 15 ) {
PM_AddEvent( EV_STEP_12 );
} else {
PM_AddEvent( EV_STEP_16 );
}
}
if ( pm->debugLevel ) {
Com_Printf("%i:stepped\n", c_pmove);
}
}
}