bg_pmove.c

3D 游戏界的大牛人 John Carmack 终于放出了 Q3 的源代码

	}

	PM_Accelerate (wishdir, wishspeed, pm_wateraccelerate);

	// make sure we can go up slopes easily under water
	if ( pml.groundPlane && DotProduct( pm->ps->velocity, pml.groundTrace.plane.normal ) < 0 ) {
		vel = VectorLength(pm->ps->velocity);
		// slide along the ground plane
		PM_ClipVelocity (pm->ps->velocity, pml.groundTrace.plane.normal, 
			pm->ps->velocity, OVERCLIP );

		VectorNormalize(pm->ps->velocity);
		VectorScale(pm->ps->velocity, vel, pm->ps->velocity);
	}

	PM_SlideMove( qfalse );
}

#ifdef MISSIONPACK
/*
===================
PM_InvulnerabilityMove

Only with the invulnerability powerup
===================
*/
static void PM_InvulnerabilityMove( void ) {
	pm->cmd.forwardmove = 0;
	pm->cmd.rightmove = 0;
	pm->cmd.upmove = 0;
	VectorClear(pm->ps->velocity);
}
#endif

/*
===================
PM_FlyMove

Only with the flight powerup
===================
*/
static void PM_FlyMove( void ) {
	int		i;
	vec3_t	wishvel;
	float	wishspeed;
	vec3_t	wishdir;
	float	scale;

	// normal slowdown
	PM_Friction ();

	scale = PM_CmdScale( &pm->cmd );
	//
	// user intentions
	//
	if ( !scale ) {
		wishvel[0] = 0;
		wishvel[1] = 0;
		wishvel[2] = 0;
	} else {
		for (i=0 ; i<3 ; i++) {
			wishvel[i] = scale * pml.forward[i]*pm->cmd.forwardmove + scale * pml.right[i]*pm->cmd.rightmove;
		}

		wishvel[2] += scale * pm->cmd.upmove;
	}

	VectorCopy (wishvel, wishdir);
	wishspeed = VectorNormalize(wishdir);

	PM_Accelerate (wishdir, wishspeed, pm_flyaccelerate);

	PM_StepSlideMove( qfalse );
}


/*
===================
PM_AirMove

===================
*/
static void PM_AirMove( void ) {
	int			i;
	vec3_t		wishvel;
	float		fmove, smove;
	vec3_t		wishdir;
	float		wishspeed;
	float		scale;
	usercmd_t	cmd;

	PM_Friction();

	fmove = pm->cmd.forwardmove;
	smove = pm->cmd.rightmove;

	cmd = pm->cmd;
	scale = PM_CmdScale( &cmd );

	// set the movementDir so clients can rotate the legs for strafing
	PM_SetMovementDir();

	// project moves down to flat plane
	pml.forward[2] = 0;
	pml.right[2] = 0;
	VectorNormalize (pml.forward);
	VectorNormalize (pml.right);

	for ( i = 0 ; i < 2 ; i++ ) {
		wishvel[i] = pml.forward[i]*fmove + pml.right[i]*smove;
	}
	wishvel[2] = 0;

	VectorCopy (wishvel, wishdir);
	wishspeed = VectorNormalize(wishdir);
	wishspeed *= scale;

	// not on ground, so little effect on velocity
	PM_Accelerate (wishdir, wishspeed, pm_airaccelerate);

	// we may have a ground plane that is very steep, even
	// though we don't have a groundentity
	// slide along the steep plane
	if ( pml.groundPlane ) {
		PM_ClipVelocity (pm->ps->velocity, pml.groundTrace.plane.normal, 
			pm->ps->velocity, OVERCLIP );
	}

#if 0
	//ZOID:  If we are on the grapple, try stair-stepping
	//this allows a player to use the grapple to pull himself
	//over a ledge
	if (pm->ps->pm_flags & PMF_GRAPPLE_PULL)
		PM_StepSlideMove ( qtrue );
	else
		PM_SlideMove ( qtrue );
#endif

	PM_StepSlideMove ( qtrue );
}

/*
===================
PM_GrappleMove

===================
*/
static void PM_GrappleMove( void ) {
	vec3_t vel, v;
	float vlen;

	VectorScale(pml.forward, -16, v);
	VectorAdd(pm->ps->grapplePoint, v, v);
	VectorSubtract(v, pm->ps->origin, vel);
	vlen = VectorLength(vel);
	VectorNormalize( vel );

	if (vlen <= 100)
		VectorScale(vel, 10 * vlen, vel);
	else
		VectorScale(vel, 800, vel);

	VectorCopy(vel, pm->ps->velocity);

	pml.groundPlane = qfalse;
}

/*
===================
PM_WalkMove

===================
*/
static void PM_WalkMove( void ) {
	int			i;
	vec3_t		wishvel;
	float		fmove, smove;
	vec3_t		wishdir;
	float		wishspeed;
	float		scale;
	usercmd_t	cmd;
	float		accelerate;
	float		vel;

	if ( pm->waterlevel > 2 && DotProduct( pml.forward, pml.groundTrace.plane.normal ) > 0 ) {
		// begin swimming
		PM_WaterMove();
		return;
	}


	if ( PM_CheckJump () ) {
		// jumped away
		if ( pm->waterlevel > 1 ) {
			PM_WaterMove();
		} else {
			PM_AirMove();
		}
		return;
	}

	PM_Friction ();

	fmove = pm->cmd.forwardmove;
	smove = pm->cmd.rightmove;

	cmd = pm->cmd;
	scale = PM_CmdScale( &cmd );

	// set the movementDir so clients can rotate the legs for strafing
	PM_SetMovementDir();

	// project moves down to flat plane
	pml.forward[2] = 0;
	pml.right[2] = 0;

	// project the forward and right directions onto the ground plane
	PM_ClipVelocity (pml.forward, pml.groundTrace.plane.normal, pml.forward, OVERCLIP );
	PM_ClipVelocity (pml.right, pml.groundTrace.plane.normal, pml.right, OVERCLIP );
	//
	VectorNormalize (pml.forward);
	VectorNormalize (pml.right);

	for ( i = 0 ; i < 3 ; i++ ) {
		wishvel[i] = pml.forward[i]*fmove + pml.right[i]*smove;
	}
	// when going up or down slopes the wish velocity should Not be zero
//	wishvel[2] = 0;

	VectorCopy (wishvel, wishdir);
	wishspeed = VectorNormalize(wishdir);
	wishspeed *= scale;

	// clamp the speed lower if ducking
	if ( pm->ps->pm_flags & PMF_DUCKED ) {
		if ( wishspeed > pm->ps->speed * pm_duckScale ) {
			wishspeed = pm->ps->speed * pm_duckScale;
		}
	}

	// clamp the speed lower if wading or walking on the bottom
	if ( pm->waterlevel ) {
		float	waterScale;

		waterScale = pm->waterlevel / 3.0;
		waterScale = 1.0 - ( 1.0 - pm_swimScale ) * waterScale;
		if ( wishspeed > pm->ps->speed * waterScale ) {
			wishspeed = pm->ps->speed * waterScale;
		}
	}

	// when a player gets hit, they temporarily lose
	// full control, which allows them to be moved a bit
	if ( ( pml.groundTrace.surfaceFlags & SURF_SLICK ) || pm->ps->pm_flags & PMF_TIME_KNOCKBACK ) {
		accelerate = pm_airaccelerate;
	} else {
		accelerate = pm_accelerate;
	}

	PM_Accelerate (wishdir, wishspeed, accelerate);

	//Com_Printf("velocity = %1.1f %1.1f %1.1f\n", pm->ps->velocity[0], pm->ps->velocity[1], pm->ps->velocity[2]);
	//Com_Printf("velocity1 = %1.1f\n", VectorLength(pm->ps->velocity));

	if ( ( pml.groundTrace.surfaceFlags & SURF_SLICK ) || pm->ps->pm_flags & PMF_TIME_KNOCKBACK ) {
		pm->ps->velocity[2] -= pm->ps->gravity * pml.frametime;
	} else {
		// don't reset the z velocity for slopes
//		pm->ps->velocity[2] = 0;
	}

	vel = VectorLength(pm->ps->velocity);

	// slide along the ground plane
	PM_ClipVelocity (pm->ps->velocity, pml.groundTrace.plane.normal, 
		pm->ps->velocity, OVERCLIP );

	// don't decrease velocity when going up or down a slope
	VectorNormalize(pm->ps->velocity);
	VectorScale(pm->ps->velocity, vel, pm->ps->velocity);

	// don't do anything if standing still
	if (!pm->ps->velocity[0] && !pm->ps->velocity[1]) {
		return;
	}

	PM_StepSlideMove( qfalse );

	//Com_Printf("velocity2 = %1.1f\n", VectorLength(pm->ps->velocity));

}


/*
==============
PM_DeadMove
==============
*/
static void PM_DeadMove( void ) {
	float	forward;

	if ( !pml.walking ) {
		return;
	}

	// extra friction

	forward = VectorLength (pm->ps->velocity);
	forward -= 20;
	if ( forward <= 0 ) {
		VectorClear (pm->ps->velocity);
	} else {
		VectorNormalize (pm->ps->velocity);
		VectorScale (pm->ps->velocity, forward, pm->ps->velocity);
	}
}


/*
===============
PM_NoclipMove
===============
*/
static void PM_NoclipMove( void ) {
	float	speed, drop, friction, control, newspeed;
	int			i;
	vec3_t		wishvel;
	float		fmove, smove;
	vec3_t		wishdir;
	float		wishspeed;
	float		scale;

	pm->ps->viewheight = DEFAULT_VIEWHEIGHT;

	// friction

	speed = VectorLength (pm->ps->velocity);
	if (speed < 1)
	{
		VectorCopy (vec3_origin, pm->ps->velocity);
	}
	else
	{
		drop = 0;

		friction = pm_friction*1.5;	// extra friction
		control = speed < pm_stopspeed ? pm_stopspeed : speed;
		drop += control*friction*pml.frametime;

		// scale the velocity
		newspeed = speed - drop;
		if (newspeed < 0)
			newspeed = 0;
		newspeed /= speed;

		VectorScale (pm->ps->velocity, newspeed, pm->ps->velocity);
	}

	// accelerate
	scale = PM_CmdScale( &pm->cmd );

	fmove = pm->cmd.forwardmove;
	smove = pm->cmd.rightmove;
	
	for (i=0 ; i<3 ; i++)
		wishvel[i] = pml.forward[i]*fmove + pml.right[i]*smove;
	wishvel[2] += pm->cmd.upmove;

	VectorCopy (wishvel, wishdir);
	wishspeed = VectorNormalize(wishdir);
	wishspeed *= scale;

	PM_Accelerate( wishdir, wishspeed, pm_accelerate );

	// move
	VectorMA (pm->ps->origin, pml.frametime, pm->ps->velocity, pm->ps->origin);
}

//============================================================================

/*
================
PM_FootstepForSurface

Returns an event number apropriate for the groundsurface
================
*/
static int PM_FootstepForSurface( void ) {
	if ( pml.groundTrace.surfaceFlags & SURF_NOSTEPS ) {
		return 0;
	}
	if ( pml.groundTrace.surfaceFlags & SURF_METALSTEPS ) {
		return EV_FOOTSTEP_METAL;
	}
	return EV_FOOTSTEP;
}


/*
=================
PM_CrashLand

Check for hard landings that generate sound events
=================
*/
static void PM_CrashLand( void ) {
	float		delta;
	float		dist;
	float		vel, acc;
	float		t;
	float		a, b, c, den;

	// decide which landing animation to use
	if ( pm->ps->pm_flags & PMF_BACKWARDS_JUMP ) {
		PM_ForceLegsAnim( LEGS_LANDB );
	} else {
		PM_ForceLegsAnim( LEGS_LAND );
	}

	pm->ps->legsTimer = TIMER_LAND;

	// calculate the exact velocity on landing
	dist = pm->ps->origin[2] - pml.previous_origin[2];
	vel = pml.previous_velocity[2];
	acc = -pm->ps->gravity;

	a = acc / 2;
	b = vel;
	c = -dist;

	den =  b * b - 4 * a * c;
	if ( den < 0 ) {
		return;
	}
	t = (-b - sqrt( den ) ) / ( 2 * a );

	delta = vel + t * acc;
	delta = delta*delta * 0.0001;

	// ducking while falling doubles damage
	if ( pm->ps->pm_flags & PMF_DUCKED ) {
		delta *= 2;
	}

	// never take falling damage if completely underwater
	if ( pm->waterlevel == 3 ) {
		return;
	}

	// reduce falling damage if there is standing water
	if ( pm->waterlevel == 2 ) {
		delta *= 0.25;
	}
	if ( pm->waterlevel == 1 ) {
		delta *= 0.5;
	}

	if ( delta < 1 ) {
		return;
	}

	// create a local entity event to play the sound

	// SURF_NODAMAGE is used for bounce pads where you don't ever
	// want to take damage or play a crunch sound
	if ( !(pml.groundTrace.surfaceFlags & SURF_NODAMAGE) )  {
		if ( delta > 60 ) {
			PM_AddEvent( EV_FALL_FAR );
		} else if ( delta > 40 ) {
			// this is a pain grunt, so don't play it if dead
			if ( pm->ps->stats[STAT_HEALTH] > 0 ) {
				PM_AddEvent( EV_FALL_MEDIUM );
			}
		} else if ( delta > 7 ) {
			PM_AddEvent( EV_FALL_SHORT );
		} else {
			PM_AddEvent( PM_FootstepForSurface() );
		}
	}

	// start footstep cycle over
	pm->ps->bobCycle = 0;
}

/*
=============
PM_CheckStuck
=============
*/
/*
void PM_CheckStuck(void) {
	trace_t trace;

	pm->trace (&trace, pm->ps->origin, pm->mins, pm->maxs, pm->ps->origin, pm->ps->clientNum, pm->tracemask);
	if (trace.allsolid) {
		//int shit = qtrue;
	}
}
*/

/*
=============
PM_CorrectAllSolid
=============
*/
static int PM_CorrectAllSolid( trace_t *trace ) {
	int			i, j, k;
	vec3_t		point;

	if ( pm->debugLevel ) {
		Com_Printf("%i:allsolid\n", c_pmove);
	}

	// jitter around
	for (i = -1; i <= 1; i++) {
		for (j = -1; j <= 1; j++) {
			for (k = -1; k <= 1; k++) {
				VectorCopy(pm->ps->origin, point);