/*
===========================================================================

Return to Castle Wolfenstein multiplayer GPL Source Code
Copyright (C) 1999-2010 id Software LLC, a ZeniMax Media company. 

This file is part of the Return to Castle Wolfenstein multiplayer GPL Source Code (RTCW MP Source Code).  

RTCW MP Source Code 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 3 of the License, or
(at your option) any later version.

RTCW MP Source Code 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 RTCW MP Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the RTCW MP Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the RTCW MP Source Code.  If not, please request a copy in writing from id Software at the address below.

If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.

===========================================================================
*/


/*****************************************************************************
 * name:		be_aas_move.c
 *
 * desc:		AAS
 *
 *
 *****************************************************************************/

#include "../game/q_shared.h"
#include "l_memory.h"
#include "l_script.h"
#include "l_precomp.h"
#include "l_struct.h"
#include "aasfile.h"
#include "../game/botlib.h"
#include "../game/be_aas.h"
#include "be_aas_funcs.h"
#include "be_aas_def.h"

//#define BSPC

extern botlib_import_t botimport;

aas_settings_t aassettings;

//#define AAS_MOVE_DEBUG

//===========================================================================
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
int AAS_DropToFloor( vec3_t origin, vec3_t mins, vec3_t maxs ) {
	vec3_t end;
	bsp_trace_t trace;

	VectorCopy( origin, end );
	end[2] -= 100;
	trace = AAS_Trace( origin, mins, maxs, end, 0, CONTENTS_SOLID );
	if ( trace.startsolid ) {
		return qfalse;
	}
	VectorCopy( trace.endpos, origin );
	return qtrue;
} //end of the function AAS_DropToFloor
//===========================================================================
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
void AAS_InitSettings( void ) {
	aassettings.sv_friction             = 6;
	aassettings.sv_stopspeed            = 100;
	aassettings.sv_gravity              = 800;
	aassettings.sv_waterfriction        = 1;
	aassettings.sv_watergravity         = 400;
	aassettings.sv_maxvelocity          = 320;
	aassettings.sv_maxwalkvelocity      = 300;
	aassettings.sv_maxcrouchvelocity    = 100;
	aassettings.sv_maxswimvelocity      = 150;
	aassettings.sv_walkaccelerate       = 10;
	aassettings.sv_airaccelerate        = 1;
	aassettings.sv_swimaccelerate       = 4;
	aassettings.sv_maxstep              = 18;
	aassettings.sv_maxsteepness         = 0.7;
	aassettings.sv_maxwaterjump         = 17;
	// Ridah, calculate maxbarrier according to jumpvel and gravity
	aassettings.sv_jumpvel              = 270;
	aassettings.sv_maxbarrier           = -0.8 + ( 0.5 * aassettings.sv_gravity * ( aassettings.sv_jumpvel / aassettings.sv_gravity ) * ( aassettings.sv_jumpvel / aassettings.sv_gravity ) );
	// done.
} //end of the function AAS_InitSettings
//===========================================================================
// returns qtrue if the bot is against a ladder
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
int AAS_AgainstLadder( vec3_t origin, int ms_areanum ) {
	int areanum, i, facenum, side;
	vec3_t org;
	aas_plane_t *plane;
	aas_face_t *face;
	aas_area_t *area;

	VectorCopy( origin, org );
	areanum = AAS_PointAreaNum( org );
	if ( !areanum ) {
		org[0] += 1;
		areanum = AAS_PointAreaNum( org );
		if ( !areanum ) {
			org[1] += 1;
			areanum = AAS_PointAreaNum( org );
			if ( !areanum ) {
				org[0] -= 2;
				areanum = AAS_PointAreaNum( org );
				if ( !areanum ) {
					org[1] -= 2;
					areanum = AAS_PointAreaNum( org );
				} //end if
			} //end if
		} //end if
	} //end if
	  //if in solid... wrrr shouldn't happen
	  //if (!areanum) return qfalse;
	  // RF, it does if they're in a monsterclip brush
	if ( !areanum ) {
		areanum = ms_areanum;
	}
	//if not in a ladder area
	if ( !( ( *aasworld ).areasettings[areanum].areaflags & AREA_LADDER ) ) {
		return qfalse;
	}
	//if a crouch only area
	if ( !( ( *aasworld ).areasettings[areanum].presencetype & PRESENCE_NORMAL ) ) {
		return qfalse;
	}
	//
	area = &( *aasworld ).areas[areanum];
	for ( i = 0; i < area->numfaces; i++ )
	{
		facenum = ( *aasworld ).faceindex[area->firstface + i];
		side = facenum < 0;
		face = &( *aasworld ).faces[abs( facenum )];
		//if the face isn't a ladder face
		if ( !( face->faceflags & FACE_LADDER ) ) {
			continue;
		}
		//get the plane the face is in
		plane = &( *aasworld ).planes[face->planenum ^ side];
		//if the origin is pretty close to the plane
		if ( abs( DotProduct( plane->normal, origin ) - plane->dist ) < 3 ) {
			if ( AAS_PointInsideFace( abs( facenum ), origin, 0.1 ) ) {
				return qtrue;
			}
		} //end if
	} //end for
	return qfalse;
} //end of the function AAS_AgainstLadder
//===========================================================================
// returns qtrue if the bot is on the ground
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
int AAS_OnGround( vec3_t origin, int presencetype, int passent ) {
	aas_trace_t trace;
	vec3_t end, up = {0, 0, 1};
	aas_plane_t *plane;

	VectorCopy( origin, end );
	end[2] -= 10;

	trace = AAS_TraceClientBBox( origin, end, presencetype, passent );

	//if in solid
	if ( trace.startsolid ) {
		return qfalse;
	}
	//if nothing hit at all
	if ( trace.fraction >= 1.0 ) {
		return qfalse;
	}
	//if too far from the hit plane
	if ( origin[2] - trace.endpos[2] > 10 ) {
		return qfalse;
	}
	//check if the plane isn't too steep
	plane = AAS_PlaneFromNum( trace.planenum );
	if ( DotProduct( plane->normal, up ) < aassettings.sv_maxsteepness ) {
		return qfalse;
	}
	//the bot is on the ground
	return qtrue;
} //end of the function AAS_OnGround
//===========================================================================
// returns qtrue if a bot at the given position is swimming
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
int AAS_Swimming( vec3_t origin ) {
	vec3_t testorg;

	VectorCopy( origin, testorg );
	testorg[2] -= 2;
	if ( AAS_PointContents( testorg ) & ( CONTENTS_LAVA | CONTENTS_SLIME | CONTENTS_WATER ) ) {
		return qtrue;
	}
	return qfalse;
} //end of the function AAS_Swimming
//===========================================================================
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
vec3_t VEC_UP           = {0, -1,  0};
vec3_t MOVEDIR_UP       = {0,  0,  1};
vec3_t VEC_DOWN     = {0, -2,  0};
vec3_t MOVEDIR_DOWN = {0,  0, -1};

void AAS_SetMovedir( vec3_t angles, vec3_t movedir ) {
	if ( VectorCompare( angles, VEC_UP ) ) {
		VectorCopy( MOVEDIR_UP, movedir );
	} //end if
	else if ( VectorCompare( angles, VEC_DOWN ) ) {
		VectorCopy( MOVEDIR_DOWN, movedir );
	} //end else if
	else
	{
		AngleVectors( angles, movedir, NULL, NULL );
	} //end else
} //end of the function AAS_SetMovedir
//===========================================================================
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
void AAS_JumpReachRunStart( aas_reachability_t *reach, vec3_t runstart ) {
	vec3_t hordir, start, cmdmove;
	aas_clientmove_t move;

	//
	hordir[0] = reach->start[0] - reach->end[0];
	hordir[1] = reach->start[1] - reach->end[1];
	hordir[2] = 0;
	VectorNormalize( hordir );
	//start point
	VectorCopy( reach->start, start );
	start[2] += 1;
	//get command movement
	VectorScale( hordir, 400, cmdmove );
	//
	AAS_PredictClientMovement( &move, -1, start, PRESENCE_NORMAL, qtrue,
							   vec3_origin, cmdmove, 1, 2, 0.1,
							   SE_ENTERWATER | SE_ENTERSLIME | SE_ENTERLAVA |
							   SE_HITGROUNDDAMAGE | SE_GAP, 0, qfalse );
	VectorCopy( move.endpos, runstart );
	//don't enter slime or lava and don't fall from too high
	if ( move.stopevent & ( SE_ENTERLAVA | SE_HITGROUNDDAMAGE ) ) { //----(SA)	modified since slime is no longer deadly
//	if (move.stopevent & (SE_ENTERSLIME|SE_ENTERLAVA|SE_HITGROUNDDAMAGE))
		VectorCopy( start, runstart );
	} //end if
} //end of the function AAS_JumpReachRunStart
//===========================================================================
// returns the Z velocity when rocket jumping at the origin
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
float AAS_WeaponJumpZVelocity( vec3_t origin, float radiusdamage ) {
	vec3_t kvel, v, start, end, forward, right, viewangles, dir;
	float mass, knockback, points;
	vec3_t rocketoffset = {8, 8, -8};
	vec3_t botmins = {-16, -16, -24};
	vec3_t botmaxs = {16, 16, 32};
	bsp_trace_t bsptrace;

	//look down (90 degrees)
	viewangles[PITCH] = 90;
	viewangles[YAW] = 0;
	viewangles[ROLL] = 0;
	//get the start point shooting from
	VectorCopy( origin, start );
	start[2] += 8; //view offset Z
	AngleVectors( viewangles, forward, right, NULL );
	start[0] += forward[0] * rocketoffset[0] + right[0] * rocketoffset[1];
	start[1] += forward[1] * rocketoffset[0] + right[1] * rocketoffset[1];
	start[2] += forward[2] * rocketoffset[0] + right[2] * rocketoffset[1] + rocketoffset[2];
	//end point of the trace
	VectorMA( start, 500, forward, end );
	//trace a line to get the impact point
	bsptrace = AAS_Trace( start, NULL, NULL, end, 1, CONTENTS_SOLID );
	//calculate the damage the bot will get from the rocket impact
	VectorAdd( botmins, botmaxs, v );
	VectorMA( origin, 0.5, v, v );
	VectorSubtract( bsptrace.endpos, v, v );
	//
	points = radiusdamage - 0.5 * VectorLength( v );
	if ( points < 0 ) {
		points = 0;
	}
	//the owner of the rocket gets half the damage
	points *= 0.5;
	//mass of the bot (p_client.c: PutClientInServer)
	mass = 200;
	//knockback is the same as the damage points
	knockback = points;
	//direction of the damage (from trace.endpos to bot origin)
	VectorSubtract( origin, bsptrace.endpos, dir );
	VectorNormalize( dir );
	//damage velocity
	VectorScale( dir, 1600.0 * (float)knockback / mass, kvel );   //the rocket jump hack...
	//rocket impact velocity + jump velocity
	return kvel[2] + aassettings.sv_jumpvel;
} //end of the function AAS_WeaponJumpZVelocity
//===========================================================================
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
float AAS_RocketJumpZVelocity( vec3_t origin ) {
	//rocket radius damage is 120 (p_weapon.c: Weapon_RocketLauncher_Fire)
	return AAS_WeaponJumpZVelocity( origin, 120 );
} //end of the function AAS_RocketJumpZVelocity
//===========================================================================
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
float AAS_BFGJumpZVelocity( vec3_t origin ) {
	//bfg radius damage is 1000 (p_weapon.c: weapon_bfg_fire)
	return AAS_WeaponJumpZVelocity( origin, 120 );
} //end of the function AAS_BFGJumpZVelocity
//===========================================================================
// applies ground friction to the given velocity
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
void AAS_Accelerate( vec3_t velocity, float frametime, vec3_t wishdir, float wishspeed, float accel ) {
	// q2 style
	int i;
	float addspeed, accelspeed, currentspeed;

	currentspeed = DotProduct( velocity, wishdir );
	addspeed = wishspeed - currentspeed;
	if ( addspeed <= 0 ) {
		return;
	}
	accelspeed = accel * frametime * wishspeed;
	if ( accelspeed > addspeed ) {
		accelspeed = addspeed;
	}

	for ( i = 0 ; i < 3 ; i++ ) {
		velocity[i] += accelspeed * wishdir[i];
	}
} //end of the function AAS_Accelerate
//===========================================================================
//
// Parameter:			-
// Returns:				-
// Changes Globals:		-
//===========================================================================
void AAS_AirControl( vec3_t start, vec3_t end, vec3_t velocity, vec3_t cmdmove ) {
	vec3_t dir;

	VectorSubtract( end, start, dir );
} //end of the function AAS_AirControl
//===========================================================================
// applies ground friction to the given velocity
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
void AAS_ApplyFriction( vec3_t vel, float friction, float stopspeed,
						float frametime ) {
	float speed, control, newspeed;

	//horizontal speed
	speed = sqrt( vel[0] * vel[0] + vel[1] * vel[1] );
	if ( speed ) {
		control = speed < stopspeed ? stopspeed : speed;
		newspeed = speed - frametime * control * friction;
		if ( newspeed < 0 ) {
			newspeed = 0;
		}
		newspeed /= speed;
		vel[0] *= newspeed;
		vel[1] *= newspeed;
	} //end if
} //end of the function AAS_ApplyFriction
//===========================================================================
// predicts the movement
// assumes regular bounding box sizes
// NOTE: out of water jumping is not included
// NOTE: grappling hook is not included
//
// Parameter:				origin			: origin to start with
//								presencetype	: presence type to start with
//								velocity			: velocity to start with
//								cmdmove			: client command movement
//								cmdframes		: number of frame cmdmove is valid
//								maxframes		: maximum number of predicted frames
//								frametime		: duration of one predicted frame
//								stopevent		: events that stop the prediction
//						stopareanum		: stop as soon as entered this area
// Returns:					aas_clientmove_t
// Changes Globals:		-
//===========================================================================
int AAS_PredictClientMovement( struct aas_clientmove_s *move,
							   int entnum, vec3_t origin,
							   int presencetype, int onground,
							   vec3_t velocity, vec3_t cmdmove,
							   int cmdframes,
							   int maxframes, float frametime,
							   int stopevent, int stopareanum, int visualize ) {
	float sv_friction, sv_stopspeed, sv_gravity, sv_waterfriction;
	float sv_watergravity;
	float sv_walkaccelerate, sv_airaccelerate, sv_swimaccelerate;
	float sv_maxwalkvelocity, sv_maxcrouchvelocity, sv_maxswimvelocity;
	float sv_maxstep, sv_maxsteepness, sv_jumpvel, friction;
	float gravity, delta, maxvel, wishspeed, accelerate;
	//float velchange, newvel;
	int n, i, j, pc, step, swimming, ax, crouch, event, jump_frame, areanum;
	int areas[20], numareas;
	vec3_t points[20];
	vec3_t org, end, feet, start, stepend, lastorg, wishdir;
	vec3_t frame_test_vel, old_frame_test_vel, left_test_vel;
	vec3_t up = {0, 0, 1};
	aas_plane_t *plane, *plane2;
	aas_trace_t trace, steptrace;

	if ( frametime <= 0 ) {
		frametime = 0.1;
	}
	//
	sv_friction = aassettings.sv_friction;
	sv_stopspeed = aassettings.sv_stopspeed;
	sv_gravity = aassettings.sv_gravity;
	sv_waterfriction = aassettings.sv_waterfriction;
	sv_watergravity = aassettings.sv_watergravity;
	sv_maxwalkvelocity = aassettings.sv_maxwalkvelocity; // * frametime;
	sv_maxcrouchvelocity = aassettings.sv_maxcrouchvelocity; // * frametime;
	sv_maxswimvelocity = aassettings.sv_maxswimvelocity; // * frametime;
	sv_walkaccelerate = aassettings.sv_walkaccelerate;
	sv_airaccelerate = aassettings.sv_airaccelerate;
	sv_swimaccelerate = aassettings.sv_swimaccelerate;
	sv_maxstep = aassettings.sv_maxstep;
	sv_maxsteepness = aassettings.sv_maxsteepness;
	sv_jumpvel = aassettings.sv_jumpvel * frametime;
	//
	memset( move, 0, sizeof( aas_clientmove_t ) );
	memset( &trace, 0, sizeof( aas_trace_t ) );
	//start at the current origin
	VectorCopy( origin, org );
	org[2] += 0.25;
	//velocity to test for the first frame
	VectorScale( velocity, frametime, frame_test_vel );
	//
	jump_frame = -1;
	//predict a maximum of 'maxframes' ahead
	for ( n = 0; n < maxframes; n++ )
	{
		swimming = AAS_Swimming( org );
		//get gravity depending on swimming or not
		gravity = swimming ? sv_watergravity : sv_gravity;
		//apply gravity at the START of the frame
		frame_test_vel[2] = frame_test_vel[2] - ( gravity * 0.1 * frametime );
		//if on the ground or swimming
		if ( onground || swimming ) {
			friction = swimming ? sv_friction : sv_waterfriction;
			//apply friction
			VectorScale( frame_test_vel, 1 / frametime, frame_test_vel );
			AAS_ApplyFriction( frame_test_vel, friction, sv_stopspeed, frametime );
			VectorScale( frame_test_vel, frametime, frame_test_vel );
		} //end if
		crouch = qfalse;
		//apply command movement
		if ( n < cmdframes ) {
			ax = 0;
			maxvel = sv_maxwalkvelocity;
			accelerate = sv_airaccelerate;
			VectorCopy( cmdmove, wishdir );
			if ( onground ) {
				if ( cmdmove[2] < -300 ) {
					crouch = qtrue;
					maxvel = sv_maxcrouchvelocity;
				} //end if
				  //if not swimming and upmove is positive then jump
				if ( !swimming && cmdmove[2] > 1 ) {
					//jump velocity minus the gravity for one frame + 5 for safety
					frame_test_vel[2] = sv_jumpvel - ( gravity * 0.1 * frametime ) + 5;
					jump_frame = n;
					//jumping so air accelerate
					accelerate = sv_airaccelerate;
				} //end if
				else
				{
					accelerate = sv_walkaccelerate;
				} //end else
				ax = 2;
			} //end if
			if ( swimming ) {
				maxvel = sv_maxswimvelocity;
				accelerate = sv_swimaccelerate;
				ax = 3;
			} //end if
			else
			{
				wishdir[2] = 0;
			} //end else
			  //
			wishspeed = VectorNormalize( wishdir );
			if ( wishspeed > maxvel ) {
				wishspeed = maxvel;
			}
			VectorScale( frame_test_vel, 1 / frametime, frame_test_vel );
			AAS_Accelerate( frame_test_vel, frametime, wishdir, wishspeed, accelerate );
			VectorScale( frame_test_vel, frametime, frame_test_vel );
			/*
			for (i = 0; i < ax; i++)
			{
				velchange = (cmdmove[i] * frametime) - frame_test_vel[i];
				if (velchange > sv_maxacceleration) velchange = sv_maxacceleration;
				else if (velchange < -sv_maxacceleration) velchange = -sv_maxacceleration;
				newvel = frame_test_vel[i] + velchange;
				//
				if (frame_test_vel[i] <= maxvel && newvel > maxvel) frame_test_vel[i] = maxvel;
				else if (frame_test_vel[i] >= -maxvel && newvel < -maxvel) frame_test_vel[i] = -maxvel;
				else frame_test_vel[i] = newvel;
			} //end for
			*/
		} //end if
		if ( crouch ) {
			presencetype = PRESENCE_CROUCH;
		} //end if
		else if ( presencetype == PRESENCE_CROUCH ) {
			if ( AAS_PointPresenceType( org ) & PRESENCE_NORMAL ) {
				presencetype = PRESENCE_NORMAL;
			} //end if
		} //end else
		  //save the current origin
		VectorCopy( org, lastorg );
		//move linear during one frame
		VectorCopy( frame_test_vel, left_test_vel );
		j = 0;
		do
		{
			VectorAdd( org, left_test_vel, end );
			//trace a bounding box
			trace = AAS_TraceClientBBox( org, end, presencetype, entnum );
			//
//#ifdef AAS_MOVE_DEBUG
			if ( visualize ) {
				if ( trace.startsolid ) {
					botimport.Print( PRT_MESSAGE, "PredictMovement: start solid\n" );
				}
				AAS_DebugLine( org, trace.endpos, LINECOLOR_RED );
			} //end if
//#endif //AAS_MOVE_DEBUG
			//
			if ( stopevent & SE_ENTERAREA ) {
				numareas = AAS_TraceAreas( org, trace.endpos, areas, points, 20 );
				for ( i = 0; i < numareas; i++ )
				{
					if ( areas[i] == stopareanum ) {
						VectorCopy( points[i], move->endpos );
						VectorScale( frame_test_vel, 1 / frametime, move->velocity );
						move->trace = trace;
						move->stopevent = SE_ENTERAREA;
						move->presencetype = presencetype;
						move->endcontents = 0;
						move->time = n * frametime;
						move->frames = n;
						return qtrue;
					} //end if
				} //end for
			} //end if
			  //move the entity to the trace end point
			VectorCopy( trace.endpos, org );
			//if there was a collision
			if ( trace.fraction < 1.0 ) {
				//get the plane the bounding box collided with
				plane = AAS_PlaneFromNum( trace.planenum );
				//
				if ( stopevent & SE_HITGROUNDAREA ) {
					if ( DotProduct( plane->normal, up ) > sv_maxsteepness ) {
						VectorCopy( org, start );
						start[2] += 0.5;
						if ( AAS_PointAreaNum( start ) == stopareanum ) {
							VectorCopy( start, move->endpos );
							VectorScale( frame_test_vel, 1 / frametime, move->velocity );
							move->trace = trace;
							move->stopevent = SE_HITGROUNDAREA;
							move->presencetype = presencetype;
							move->endcontents = 0;
							move->time = n * frametime;
							move->frames = n;
							return qtrue;
						} //end if
					} //end if
				} //end if
				  //assume there's no step
				step = qfalse;
				//if it is a vertical plane and the bot didn't jump recently
				if ( plane->normal[2] == 0 && ( jump_frame < 0 || n - jump_frame > 2 ) ) {
					//check for a step
					VectorMA( org, -0.25, plane->normal, start );
					VectorCopy( start, stepend );
					start[2] += sv_maxstep;
					steptrace = AAS_TraceClientBBox( start, stepend, presencetype, entnum );
					//
					if ( !steptrace.startsolid ) {
						plane2 = AAS_PlaneFromNum( steptrace.planenum );
						if ( DotProduct( plane2->normal, up ) > sv_maxsteepness ) {
							VectorSubtract( end, steptrace.endpos, left_test_vel );
							left_test_vel[2] = 0;
							frame_test_vel[2] = 0;
//#ifdef AAS_MOVE_DEBUG
							if ( visualize ) {
								if ( steptrace.endpos[2] - org[2] > 0.125 ) {
									VectorCopy( org, start );
									start[2] = steptrace.endpos[2];
									AAS_DebugLine( org, start, LINECOLOR_BLUE );
								} //end if
							} //end if
//#endif //AAS_MOVE_DEBUG
							org[2] = steptrace.endpos[2];
							step = qtrue;
						} //end if
					} //end if
				} //end if
				  //
				if ( !step ) {
					//velocity left to test for this frame is the projection
					//of the current test velocity into the hit plane
					VectorMA( left_test_vel, -DotProduct( left_test_vel, plane->normal ),
							  plane->normal, left_test_vel );
					//store the old velocity for landing check
					VectorCopy( frame_test_vel, old_frame_test_vel );
					//test velocity for the next frame is the projection
					//of the velocity of the current frame into the hit plane
					VectorMA( frame_test_vel, -DotProduct( frame_test_vel, plane->normal ),
							  plane->normal, frame_test_vel );
					//check for a landing on an almost horizontal floor
					if ( DotProduct( plane->normal, up ) > sv_maxsteepness ) {
						onground = qtrue;
					} //end if
					if ( stopevent & SE_HITGROUNDDAMAGE ) {
						delta = 0;
						if ( old_frame_test_vel[2] < 0 &&
							 frame_test_vel[2] > old_frame_test_vel[2] &&
							 !onground ) {
							delta = old_frame_test_vel[2];
						} //end if
						else if ( onground ) {
							delta = frame_test_vel[2] - old_frame_test_vel[2];
						} //end else
						if ( delta ) {
							delta = delta * 10;
							delta = delta * delta * 0.0001;
							if ( swimming ) {
								delta = 0;
							}
							// never take falling damage if completely underwater
							/*
							if (ent->waterlevel == 3) return;
							if (ent->waterlevel == 2) delta *= 0.25;
							if (ent->waterlevel == 1) delta *= 0.5;
							*/
							if ( delta > 40 ) {
								VectorCopy( org, move->endpos );
								VectorCopy( frame_test_vel, move->velocity );
								move->trace = trace;
								move->stopevent = SE_HITGROUNDDAMAGE;
								move->presencetype = presencetype;
								move->endcontents = 0;
								move->time = n * frametime;
								move->frames = n;
								return qtrue;
							} //end if
						} //end if
					} //end if
				} //end if
			} //end if
			  //extra check to prevent endless loop
			if ( ++j > 20 ) {
				return qfalse;
			}
			//while there is a plane hit
		} while ( trace.fraction < 1.0 );
		//if going down
		if ( frame_test_vel[2] <= 10 ) {
			//check for a liquid at the feet of the bot
			VectorCopy( org, feet );
			feet[2] -= 22;
			pc = AAS_PointContents( feet );
			//get event from pc
			event = SE_NONE;
			if ( pc & CONTENTS_LAVA ) {
				event |= SE_ENTERLAVA;
			}
			if ( pc & CONTENTS_SLIME ) {
				event |= SE_ENTERSLIME;
			}
			if ( pc & CONTENTS_WATER ) {
				event |= SE_ENTERWATER;
			}
			//
			areanum = AAS_PointAreaNum( org );
			if ( ( *aasworld ).areasettings[areanum].contents & AREACONTENTS_LAVA ) {
				event |= SE_ENTERLAVA;
			}
			if ( ( *aasworld ).areasettings[areanum].contents & AREACONTENTS_SLIME ) {
				event |= SE_ENTERSLIME;
			}
			if ( ( *aasworld ).areasettings[areanum].contents & AREACONTENTS_WATER ) {
				event |= SE_ENTERWATER;
			}
			//if in lava or slime
			if ( event & stopevent ) {
				VectorCopy( org, move->endpos );
				VectorScale( frame_test_vel, 1 / frametime, move->velocity );
				move->stopevent = event & stopevent;
				move->presencetype = presencetype;
				move->endcontents = pc;
				move->time = n * frametime;
				move->frames = n;
				return qtrue;
			} //end if
		} //end if
		  //
		onground = AAS_OnGround( org, presencetype, entnum );
		//if onground and on the ground for at least one whole frame
		if ( onground ) {
			if ( stopevent & SE_HITGROUND ) {
				VectorCopy( org, move->endpos );
				VectorScale( frame_test_vel, 1 / frametime, move->velocity );
				move->trace = trace;
				move->stopevent = SE_HITGROUND;
				move->presencetype = presencetype;
				move->endcontents = 0;
				move->time = n * frametime;
				move->frames = n;
				return qtrue;
			} //end if
		} //end if
		else if ( stopevent & SE_LEAVEGROUND ) {
			VectorCopy( org, move->endpos );
			VectorScale( frame_test_vel, 1 / frametime, move->velocity );
			move->trace = trace;
			move->stopevent = SE_LEAVEGROUND;
			move->presencetype = presencetype;
			move->endcontents = 0;
			move->time = n * frametime;
			move->frames = n;
			return qtrue;
		} //end else if
		else if ( stopevent & SE_GAP ) {
			aas_trace_t gaptrace;

			VectorCopy( org, start );
			VectorCopy( start, end );
			end[2] -= 48 + aassettings.sv_maxbarrier;
			gaptrace = AAS_TraceClientBBox( start, end, PRESENCE_CROUCH, -1 );
			//if solid is found the bot cannot walk any further and will not fall into a gap
			if ( !gaptrace.startsolid ) {
				//if it is a gap (lower than one step height)
				if ( gaptrace.endpos[2] < org[2] - aassettings.sv_maxstep - 1 ) {
					if ( !( AAS_PointContents( end ) & ( CONTENTS_WATER | CONTENTS_SLIME ) ) ) { //----(SA)	modified since slime is no longer deadly
//					if (!(AAS_PointContents(end) & CONTENTS_WATER))
						VectorCopy( lastorg, move->endpos );
						VectorScale( frame_test_vel, 1 / frametime, move->velocity );
						move->trace = trace;
						move->stopevent = SE_GAP;
						move->presencetype = presencetype;
						move->endcontents = 0;
						move->time = n * frametime;
						move->frames = n;
						return qtrue;
					} //end if
				} //end if
			} //end if
		} //end else if
		if ( stopevent & SE_TOUCHJUMPPAD ) {
			if ( ( *aasworld ).areasettings[AAS_PointAreaNum( org )].contents & AREACONTENTS_JUMPPAD ) {
				VectorCopy( org, move->endpos );
				VectorScale( frame_test_vel, 1 / frametime, move->velocity );
				move->trace = trace;
				move->stopevent = SE_TOUCHJUMPPAD;
				move->presencetype = presencetype;
				move->endcontents = 0;
				move->time = n * frametime;
				move->frames = n;
				return qtrue;
			} //end if
		} //end if
		if ( stopevent & SE_TOUCHTELEPORTER ) {
			if ( ( *aasworld ).areasettings[AAS_PointAreaNum( org )].contents & AREACONTENTS_TELEPORTER ) {
				VectorCopy( org, move->endpos );
				VectorScale( frame_test_vel, 1 / frametime, move->velocity );
				move->trace = trace;
				move->stopevent = SE_TOUCHTELEPORTER;
				move->presencetype = presencetype;
				move->endcontents = 0;
				move->time = n * frametime;
				move->frames = n;
				return qtrue;
			} //end if
		} //end if
	} //end for
	  //
	VectorCopy( org, move->endpos );
	VectorScale( frame_test_vel, 1 / frametime, move->velocity );
	move->stopevent = SE_NONE;
	move->presencetype = presencetype;
	move->endcontents = 0;
	move->time = n * frametime;
	move->frames = n;
	//
	return qtrue;
} //end of the function AAS_PredictClientMovement
//===========================================================================
//
// Parameter:				-
// Returns:					-
// Changes Globals:		-
//===========================================================================
void AAS_TestMovementPrediction( int entnum, vec3_t origin, vec3_t dir ) {
	vec3_t velocity, cmdmove;
	aas_clientmove_t move;

	VectorClear( velocity );
	if ( !AAS_Swimming( origin ) ) {
		dir[2] = 0;
	}
	VectorNormalize( dir );
	VectorScale( dir, 400, cmdmove );
	cmdmove[2] = 224;
	AAS_ClearShownDebugLines();
	AAS_PredictClientMovement( &move, entnum, origin, PRESENCE_NORMAL, qtrue,
							   velocity, cmdmove, 13, 13, 0.1, SE_HITGROUND, 0, qtrue );    //SE_LEAVEGROUND);
	if ( move.stopevent & SE_LEAVEGROUND ) {
		botimport.Print( PRT_MESSAGE, "leave ground\n" );
	} //end if
} //end of the function TestMovementPrediction
//===========================================================================
// calculates the horizontal velocity needed to perform a jump from start
// to end
//
// Parameter:				zvel		: z velocity for jump
//								start		: start position of jump
//								end		: end position of jump
//								*speed	: returned speed for jump
// Returns:					qfalse if too high or too far from start to end
// Changes Globals:		-
//===========================================================================
int AAS_HorizontalVelocityForJump( float zvel, vec3_t start, vec3_t end, float *velocity ) {
	float sv_gravity, sv_maxvelocity;
	float maxjump, height2fall, t, top;
	vec3_t dir;

	sv_gravity = aassettings.sv_gravity;
	sv_maxvelocity = aassettings.sv_maxvelocity;

	//maximum height a player can jump with the given initial z velocity
	maxjump = 0.5 * sv_gravity * ( zvel / sv_gravity ) * ( zvel / sv_gravity );
	//top of the parabolic jump
	top = start[2] + maxjump;
	//height the bot will fall from the top
	height2fall = top - end[2];
	//if the goal is to high to jump to
	if ( height2fall < 0 ) {
		*velocity = sv_maxvelocity;
		return 0;
	} //end if
	  //time a player takes to fall the height
	t = sqrt( height2fall / ( 0.5 * sv_gravity ) );
	//direction from start to end
	VectorSubtract( end, start, dir );
	//calculate horizontal speed
	*velocity = sqrt( dir[0] * dir[0] + dir[1] * dir[1] ) / ( t + zvel / sv_gravity );
	//the horizontal speed must be lower than the max speed
	if ( *velocity > sv_maxvelocity ) {
		*velocity = sv_maxvelocity;
		return 0;
	} //end if
	return 1;
} //end of the function AAS_HorizontalVelocityForJump
