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

Doom 3 BFG Edition GPL Source Code
Copyright (C) 1993-2012 id Software LLC, a ZeniMax Media company.

This file is part of the Doom 3 BFG Edition GPL Source Code ("Doom 3 BFG Edition Source Code").

Doom 3 BFG Edition 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.

Doom 3 BFG Edition 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 Doom 3 BFG Edition Source Code.  If not, see <http://www.gnu.org/licenses/>.

In addition, the Doom 3 BFG Edition 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 Doom 3 BFG Edition 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.

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

#include "../idlib/precompiled.h"
#pragma hdrstop

#include "Game_local.h"


CLASS_DECLARATION( idEntity, idBrittleFracture )
EVENT( EV_Activate, idBrittleFracture::Event_Activate )
EVENT( EV_Touch, idBrittleFracture::Event_Touch )
END_CLASS

const int SHARD_ALIVE_TIME	= 5000;
const int SHARD_FADE_START	= 2000;

static const char* brittleFracture_SnapshotName = "_BrittleFracture_Snapshot_";

/*
================
idBrittleFracture::idBrittleFracture
================
*/
idBrittleFracture::idBrittleFracture()
{
	material = NULL;
	decalMaterial = NULL;
	decalSize = 0.0f;
	maxShardArea = 0.0f;
	maxShatterRadius = 0.0f;
	minShatterRadius = 0.0f;
	linearVelocityScale = 0.0f;
	angularVelocityScale = 0.0f;
	shardMass = 0.0f;
	density = 0.0f;
	friction = 0.0f;
	bouncyness = 0.0f;
	fxFracture.Clear();
	
	bounds.Clear();
	disableFracture = false;
	
	lastRenderEntityUpdate = -1;
	changed = false;
	
	fl.networkSync = true;
	
	isXraySurface = false;
}

/*
================
idBrittleFracture::~idBrittleFracture
================
*/
idBrittleFracture::~idBrittleFracture()
{
	int i;
	
	for( i = 0; i < shards.Num(); i++ )
	{
		shards[i]->decals.DeleteContents( true );
		delete shards[i];
	}
	
	// make sure the render entity is freed before the model is freed
	FreeModelDef();
	renderModelManager->FreeModel( renderEntity.hModel );
	
	// Free our events list memory
	storedEvents.Clear();
}

/*
================
idBrittleFracture::Save
================
*/
void idBrittleFracture::Save( idSaveGame* savefile ) const
{

	savefile->WriteInt( health );
	entityFlags_s flags = fl;
	LittleBitField( &flags, sizeof( flags ) );
	savefile->Write( &flags, sizeof( flags ) );
	
	// setttings
	savefile->WriteMaterial( material );
	savefile->WriteMaterial( decalMaterial );
	savefile->WriteFloat( decalSize );
	savefile->WriteFloat( maxShardArea );
	savefile->WriteFloat( maxShatterRadius );
	savefile->WriteFloat( minShatterRadius );
	savefile->WriteFloat( linearVelocityScale );
	savefile->WriteFloat( angularVelocityScale );
	savefile->WriteFloat( shardMass );
	savefile->WriteFloat( density );
	savefile->WriteFloat( friction );
	savefile->WriteFloat( bouncyness );
	savefile->WriteString( fxFracture );
	
	// state
	savefile->WriteBounds( bounds );
	savefile->WriteBool( disableFracture );
	
	savefile->WriteInt( lastRenderEntityUpdate );
	savefile->WriteBool( changed );
	
	savefile->WriteModel( defaultRenderModel );
	
	// So we can re-break the object on load if needed
	savefile->WriteInt( storedEvents.Num() );
	for( int i = 0; i < storedEvents.Num(); ++i )
	{
		savefile->WriteInt( storedEvents[i].eventType );
		savefile->WriteVec3( storedEvents[i].point );
		savefile->WriteVec3( storedEvents[i].vector );
	}
	savefile->WriteBool( isXraySurface );
}

/*
================
idBrittleFracture::Restore
================
*/
void idBrittleFracture::Restore( idRestoreGame* savefile )
{

	savefile->ReadInt( health );
	savefile->Read( &fl, sizeof( fl ) );
	LittleBitField( &fl, sizeof( fl ) );
	
	// setttings
	savefile->ReadMaterial( material );
	savefile->ReadMaterial( decalMaterial );
	savefile->ReadFloat( decalSize );
	savefile->ReadFloat( maxShardArea );
	savefile->ReadFloat( maxShatterRadius );
	savefile->ReadFloat( minShatterRadius );
	savefile->ReadFloat( linearVelocityScale );
	savefile->ReadFloat( angularVelocityScale );
	savefile->ReadFloat( shardMass );
	savefile->ReadFloat( density );
	savefile->ReadFloat( friction );
	savefile->ReadFloat( bouncyness );
	savefile->ReadString( fxFracture );
	
	// state
	savefile->ReadBounds( bounds );
	savefile->ReadBool( disableFracture );
	
	savefile->ReadInt( lastRenderEntityUpdate );
	savefile->ReadBool( changed );
	
	savefile->ReadModel( defaultRenderModel );
	
	// Reset all brittle Fractures so we can re-break them if necessary
	fl.takedamage = true;
	CreateFractures( defaultRenderModel );
	FindNeighbours();
	
	int numEvents = 0;
	bool resolveBreaks = false;
	savefile->ReadInt( numEvents );
	for( int i = 0; i < numEvents; i++ )
	{
		fractureEvent_s restoredEvent;
		
		savefile->ReadInt( restoredEvent.eventType );
		savefile->ReadVec3( restoredEvent.point );
		savefile->ReadVec3( restoredEvent.vector );
		
		if( restoredEvent.eventType == EVENT_PROJECT_DECAL )
		{
			ProjectDecal( restoredEvent.point, restoredEvent.vector, gameLocal.time, NULL );
		}
		else
		{
			Shatter( restoredEvent.point, restoredEvent.vector, gameLocal.time );
		}
		resolveBreaks = true;
	}
	
	// remove any dropped shards
	for( int i = 0; resolveBreaks && i < shards.Num(); i++ )
	{
		if( shards[i]->droppedTime != -1 )
		{
			RemoveShard( i );
			i--;
		}
	}
	
	renderEntity.hModel = renderModelManager->AllocModel();
	renderEntity.hModel->InitEmpty( brittleFracture_SnapshotName );
	renderEntity.callback = idBrittleFracture::ModelCallback;
	renderEntity.noShadow = true;
	renderEntity.noSelfShadow = true;
	renderEntity.noDynamicInteractions = false;
	
	savefile->ReadBool( isXraySurface );
}

/*
================
idBrittleFracture::Spawn
================
*/
void idBrittleFracture::Spawn()
{

	// get shard properties
	decalMaterial = declManager->FindMaterial( spawnArgs.GetString( "mtr_decal" ) );
	decalSize = spawnArgs.GetFloat( "decalSize", "40" );
	maxShardArea = spawnArgs.GetFloat( "maxShardArea", "200" ) * 2.0f ;
	maxShardArea = idMath::ClampFloat( 100, 10000, maxShardArea );
	maxShatterRadius = spawnArgs.GetFloat( "maxShatterRadius", "40" );
	minShatterRadius = spawnArgs.GetFloat( "minShatterRadius", "10" );
	linearVelocityScale = spawnArgs.GetFloat( "linearVelocityScale", "0.1" );
	angularVelocityScale = spawnArgs.GetFloat( "angularVelocityScale", "40" );
	fxFracture = spawnArgs.GetString( "fx" );
	
	// make sure that max is greater than min  ( otherwise negative number square root happens )
	if( maxShatterRadius < minShatterRadius )
	{
		idLib::Warning( "BrittleFracture, minShatterRadius(%2f) is greater than maxShatterRadius(%2f). Unknown results will ensue.", minShatterRadius, maxShatterRadius );
	}
	
	// get rigid body properties
	shardMass = spawnArgs.GetFloat( "shardMass", "20" );
	shardMass = idMath::ClampFloat( 0.001f, 1000.0f, shardMass );
	spawnArgs.GetFloat( "density", "0.1", density );
	density = idMath::ClampFloat( 0.001f, 1000.0f, density );
	spawnArgs.GetFloat( "friction", "0.4", friction );
	friction = idMath::ClampFloat( 0.0f, 1.0f, friction );
	spawnArgs.GetFloat( "bouncyness", "0.01", bouncyness );
	bouncyness = idMath::ClampFloat( 0.0f, 1.0f, bouncyness );
	
	disableFracture = spawnArgs.GetBool( "disableFracture", "0" );
	health = spawnArgs.GetInt( "health", "40" );
	fl.takedamage = true;
	
	// FIXME: set "bleed" so idProjectile calls AddDamageEffect
	spawnArgs.SetBool( "bleed", 1 );
	
	// check for xray surface
	if( renderEntity.hModel != NULL )
	{
		const idRenderModel* model = renderEntity.hModel;
		
		isXraySurface = false;
		
		for( int i = 0; i < model->NumSurfaces(); i++ )
		{
			const modelSurface_t* surf = model->Surface( i );
			
			if( idStr( surf->shader->GetName() ) == "textures/smf/window_scratch" )
			{
				isXraySurface = true;
				break;
			}
		}
	}
	
	CreateFractures( renderEntity.hModel );
	
	FindNeighbours();
	
	defaultRenderModel = renderEntity.hModel;
	renderEntity.hModel = renderModelManager->AllocModel();
	renderEntity.hModel->InitEmpty( brittleFracture_SnapshotName );
	renderEntity.callback = idBrittleFracture::ModelCallback;
	renderEntity.noShadow = true;
	renderEntity.noSelfShadow = true;
	renderEntity.noDynamicInteractions = false;
}

/*
================
idBrittleFracture::AddShard
================
*/
void idBrittleFracture::AddShard( idClipModel* clipModel, idFixedWinding& w )
{
	shard_t* shard = new( TAG_PARTICLE ) shard_t;
	shard->clipModel = clipModel;
	shard->droppedTime = -1;
	shard->winding = w;
	shard->decals.Clear();
	shard->edgeHasNeighbour.AssureSize( w.GetNumPoints(), false );
	shard->neighbours.Clear();
	shard->atEdge = false;
	shards.Append( shard );
}

/*
================
idBrittleFracture::RemoveShard
================
*/
void idBrittleFracture::RemoveShard( int index )
{
	int i;
	
	delete shards[index];
	shards.RemoveIndex( index );
	physicsObj.RemoveIndex( index );
	
	for( i = index; i < shards.Num(); i++ )
	{
		shards[i]->clipModel->SetId( i );
	}
}

/*
================
idBrittleFracture::UpdateRenderEntity
================
*/
bool idBrittleFracture::UpdateRenderEntity( renderEntity_s* renderEntity, const renderView_t* renderView ) const
{
	int i, j, k, n, msec, numTris, numDecalTris;
	float fade;
	dword packedColor;
	srfTriangles_t* tris, *decalTris;
	modelSurface_t surface;
	idDrawVert* v;
	idPlane plane;
	idMat3 tangents;
	
	// this may be triggered by a model trace or other non-view related source,
	// to which we should look like an empty model
	if( !renderView )
	{
		return false;
	}
	
	// don't regenerate it if it is current
	if( lastRenderEntityUpdate == gameLocal.time || !changed )
	{
		return false;
	}
	
	lastRenderEntityUpdate = gameLocal.time;
	changed = false;
	
	numTris = 0;
	numDecalTris = 0;
	for( i = 0; i < shards.Num(); i++ )
	{
		n = shards[i]->winding.GetNumPoints();
		if( n > 2 )
		{
			numTris += n - 2;
		}
		for( k = 0; k < shards[i]->decals.Num(); k++ )
		{
			n = shards[i]->decals[k]->GetNumPoints();
			if( n > 2 )
			{
				numDecalTris += n - 2;
			}
		}
	}
	
	// FIXME: re-use model surfaces
	renderEntity->hModel->InitEmpty( brittleFracture_SnapshotName );
	
	// allocate triangle surfaces for the fractures and decals
	tris = renderEntity->hModel->AllocSurfaceTriangles( numTris * 3, material->ShouldCreateBackSides() ? numTris * 6 : numTris * 3 );
	decalTris = renderEntity->hModel->AllocSurfaceTriangles( numDecalTris * 3, decalMaterial->ShouldCreateBackSides() ? numDecalTris * 6 : numDecalTris * 3 );
	
	for( i = 0; i < shards.Num(); i++ )
	{
		const idVec3& origin = shards[i]->clipModel->GetOrigin();
		const idMat3& axis = shards[i]->clipModel->GetAxis();
		
		fade = 1.0f;
		if( shards[i]->droppedTime >= 0 )
		{
			msec = gameLocal.time - shards[i]->droppedTime - SHARD_FADE_START;
			if( msec > 0 )
			{
				fade = 1.0f - ( float ) msec / ( SHARD_ALIVE_TIME - SHARD_FADE_START );
			}
		}
		
		packedColor = PackColor( idVec4( renderEntity->shaderParms[ SHADERPARM_RED ] * fade,
										 renderEntity->shaderParms[ SHADERPARM_GREEN ] * fade,
										 renderEntity->shaderParms[ SHADERPARM_BLUE ] * fade,
										 fade ) );
										 
		const idWinding& winding = shards[i]->winding;
		
		winding.GetPlane( plane );
		tangents = ( plane.Normal() * axis ).ToMat3();
		
		for( j = 2; j < winding.GetNumPoints(); j++ )
		{
		
			v = &tris->verts[tris->numVerts++];
			v->Clear();
			v->xyz = origin + winding[0].ToVec3() * axis;
			v->SetTexCoord( winding[0].s, winding[0].t );
			v->SetNormal( tangents[0] );
			v->SetTangent( tangents[1] );
			v->SetBiTangent( tangents[2] );
			v->SetColor( packedColor );
			
			v = &tris->verts[tris->numVerts++];
			v->Clear();
			v->xyz = origin + winding[j - 1].ToVec3() * axis;
			v->SetTexCoord( winding[j - 1].s, winding[j - 1].t );
			v->SetNormal( tangents[0] );
			v->SetTangent( tangents[1] );
			v->SetBiTangent( tangents[2] );
			v->SetColor( packedColor );
			
			v = &tris->verts[tris->numVerts++];
			v->Clear();
			v->xyz = origin + winding[j].ToVec3() * axis;
			v->SetTexCoord( winding[j].s, winding[j].t );
			v->SetNormal( tangents[0] );
			v->SetTangent( tangents[1] );
			v->SetBiTangent( tangents[2] );
			v->SetColor( packedColor );
			
			tris->indexes[tris->numIndexes++] = tris->numVerts - 3;
			tris->indexes[tris->numIndexes++] = tris->numVerts - 2;
			tris->indexes[tris->numIndexes++] = tris->numVerts - 1;
			
			if( material->ShouldCreateBackSides() )
			{
			
				tris->indexes[tris->numIndexes++] = tris->numVerts - 2;
				tris->indexes[tris->numIndexes++] = tris->numVerts - 3;
				tris->indexes[tris->numIndexes++] = tris->numVerts - 1;
			}
		}
		
		for( k = 0; k < shards[i]->decals.Num(); k++ )
		{
			const idWinding& decalWinding = *shards[i]->decals[k];
			
			for( j = 2; j < decalWinding.GetNumPoints(); j++ )
			{
			
				v = &decalTris->verts[decalTris->numVerts++];
				v->Clear();
				v->xyz = origin + decalWinding[0].ToVec3() * axis;
				v->SetTexCoord( decalWinding[0].s, decalWinding[0].t );
				v->SetNormal( tangents[0] );
				v->SetTangent( tangents[1] );
				v->SetBiTangent( tangents[2] );
				v->SetColor( packedColor );
				
				v = &decalTris->verts[decalTris->numVerts++];
				v->Clear();
				v->xyz = origin + decalWinding[j - 1].ToVec3() * axis;
				v->SetTexCoord( decalWinding[j - 1].s, decalWinding[j - 1].t );
				v->SetNormal( tangents[0] );
				v->SetTangent( tangents[1] );
				v->SetBiTangent( tangents[2] );
				v->SetColor( packedColor );
				
				v = &decalTris->verts[decalTris->numVerts++];
				v->Clear();
				v->xyz = origin + decalWinding[j].ToVec3() * axis;
				v->SetTexCoord( decalWinding[j].s, decalWinding[j].t );
				v->SetNormal( tangents[0] );
				v->SetTangent( tangents[1] );
				v->SetBiTangent( tangents[2] );
				v->SetColor( packedColor );
				
				decalTris->indexes[decalTris->numIndexes++] = decalTris->numVerts - 3;
				decalTris->indexes[decalTris->numIndexes++] = decalTris->numVerts - 2;
				decalTris->indexes[decalTris->numIndexes++] = decalTris->numVerts - 1;
				
				if( decalMaterial->ShouldCreateBackSides() )
				{
				
					decalTris->indexes[decalTris->numIndexes++] = decalTris->numVerts - 2;
					decalTris->indexes[decalTris->numIndexes++] = decalTris->numVerts - 3;
					decalTris->indexes[decalTris->numIndexes++] = decalTris->numVerts - 1;
				}
			}
		}
	}
	
	tris->tangentsCalculated = true;
	decalTris->tangentsCalculated = true;
	
	SIMDProcessor->MinMax( tris->bounds[0], tris->bounds[1], tris->verts, tris->numVerts );
	SIMDProcessor->MinMax( decalTris->bounds[0], decalTris->bounds[1], decalTris->verts, decalTris->numVerts );
	
	memset( &surface, 0, sizeof( surface ) );
	surface.shader = material;
	surface.id = 0;
	surface.geometry = tris;
	renderEntity->hModel->AddSurface( surface );
	
	memset( &surface, 0, sizeof( surface ) );
	surface.shader = decalMaterial;
	surface.id = 1;
	surface.geometry = decalTris;
	renderEntity->hModel->AddSurface( surface );
	
	return true;
}

/*
================
idBrittleFracture::ModelCallback
================
*/
bool idBrittleFracture::ModelCallback( renderEntity_s* renderEntity, const renderView_t* renderView )
{
	const idBrittleFracture* ent;
	
	ent = static_cast<idBrittleFracture*>( gameLocal.entities[ renderEntity->entityNum ] );
	if( ent == NULL )
	{
		gameLocal.Error( "idBrittleFracture::ModelCallback: callback with NULL game entity" );
		return false;
	}
	
	return ent->UpdateRenderEntity( renderEntity, renderView );
}

/*
================
idBrittleFracture::Present
================
*/
void idBrittleFracture::Present()
{

	// don't present to the renderer if the entity hasn't changed
	if( !( thinkFlags & TH_UPDATEVISUALS ) )
	{
		return;
	}
	BecomeInactive( TH_UPDATEVISUALS );
	
	renderEntity.bounds = bounds;
	renderEntity.origin.Zero();
	renderEntity.axis.Identity();
	
	// force an update because the bounds/origin/axis may stay the same while the model changes
	renderEntity.forceUpdate = true;
	
	// add to refresh list
	if( modelDefHandle == -1 )
	{
		modelDefHandle = gameRenderWorld->AddEntityDef( &renderEntity );
	}
	else
	{
		gameRenderWorld->UpdateEntityDef( modelDefHandle, &renderEntity );
	}
	
	changed = true;
}

/*
================
idBrittleFracture::Think
================
*/
void idBrittleFracture::Think()
{
	int i, startTime, endTime, droppedTime;
	shard_t* shard;
	bool atRest = true, fading = false;
	
	// remove overdue shards
	for( i = 0; i < shards.Num(); i++ )
	{
		droppedTime = shards[i]->droppedTime;
		if( droppedTime != -1 )
		{
			if( gameLocal.time - droppedTime > SHARD_ALIVE_TIME )
			{
				RemoveShard( i );
				i--;
			}
			fading = true;
		}
	}
	
	// remove the entity when nothing is visible
	if( !shards.Num() )
	{
		PostEventMS( &EV_Remove, 0 );
		return;
	}
	
	if( thinkFlags & TH_PHYSICS )
	{
	
		startTime = gameLocal.previousTime;
		endTime = gameLocal.time;
		
		// run physics on shards
		for( i = 0; i < shards.Num(); i++ )
		{
			shard = shards[i];
			
			if( shard->droppedTime == -1 )
			{
				continue;
			}
			
			shard->physicsObj.Evaluate( endTime - startTime, endTime );
			
			if( !shard->physicsObj.IsAtRest() )
			{
				atRest = false;
			}
		}
		
		if( atRest )
		{
			BecomeInactive( TH_PHYSICS );
		}
		else
		{
			BecomeActive( TH_PHYSICS );
		}
	}
	
	if( !atRest || bounds.IsCleared() )
	{
		bounds.Clear();
		for( i = 0; i < shards.Num(); i++ )
		{
			bounds.AddBounds( shards[i]->clipModel->GetAbsBounds() );
		}
	}
	
	if( fading )
	{
		BecomeActive( TH_UPDATEVISUALS | TH_THINK );
	}
	else
	{
		BecomeInactive( TH_THINK );
	}
	
	RunPhysics();
	Present();
}

/*
================
idBrittleFracture::ApplyImpulse
================
*/
void idBrittleFracture::ApplyImpulse( idEntity* ent, int id, const idVec3& point, const idVec3& impulse )
{

	if( id < 0 || id >= shards.Num() )
	{
		return;
	}
	
	if( shards[id]->droppedTime != -1 )
	{
		shards[id]->physicsObj.ApplyImpulse( 0, point, impulse );
	}
	else if( health <= 0 && !disableFracture )
	{
		Shatter( point, impulse, gameLocal.time );
	}
}

/*
================
idBrittleFracture::AddForce
================
*/
void idBrittleFracture::AddForce( idEntity* ent, int id, const idVec3& point, const idVec3& force )
{

	if( id < 0 || id >= shards.Num() )
	{
		return;
	}
	
	if( shards[id]->droppedTime != -1 )
	{
		shards[id]->physicsObj.AddForce( 0, point, force );
	}
	else if( health <= 0 && !disableFracture )
	{
		Shatter( point, force, gameLocal.time );
	}
}

/*
================
idBrittleFracture::ProjectDecal
================
*/
void idBrittleFracture::ProjectDecal( const idVec3& point, const idVec3& dir, const int time, const char* damageDefName )
{
	int i, j, bits, clipBits;
	float a, c, s;
	idVec2 st[MAX_POINTS_ON_WINDING];
	idVec3 origin;
	idMat3 axis, axistemp;
	idPlane textureAxis[2];
	
	if( common->IsServer() )
	{
		idBitMsg	msg;
		byte		msgBuf[MAX_EVENT_PARAM_SIZE];
		
		msg.InitWrite( msgBuf, sizeof( msgBuf ) );
		msg.BeginWriting();
		msg.WriteFloat( point[0] );
		msg.WriteFloat( point[1] );
		msg.WriteFloat( point[2] );
		msg.WriteFloat( dir[0] );
		msg.WriteFloat( dir[1] );
		msg.WriteFloat( dir[2] );
		ServerSendEvent( EVENT_PROJECT_DECAL, &msg, true );
	}
	
	// store the event so we can rebuilt the fracture after loading a save
	fractureEvent_s fractureEvent;
	fractureEvent.eventType = EVENT_PROJECT_DECAL;
	fractureEvent.point = point;
	fractureEvent.vector = dir;
	storedEvents.Append( fractureEvent );
	
	if( time >= gameLocal.time )
	{
		// try to get the sound from the damage def
		const idDeclEntityDef* damageDef = NULL;
		const idSoundShader* sndShader = NULL;
		if( damageDefName )
		{
			damageDef = gameLocal.FindEntityDef( damageDefName, false );
			if( damageDef )
			{
				const char* sndName = damageDef->dict.GetString( "snd_shatter", "" );
				if( sndName[0] != 0 )
				{
					sndShader = declManager->FindSound( sndName );
				}
			}
		}
		
		if( sndShader )
		{
			StartSoundShader( sndShader, SND_CHANNEL_ANY, 0, false, NULL );
		}
		else
		{
			StartSound( "snd_bullethole", SND_CHANNEL_ANY, 0, false, NULL );
		}
	}
	
	a = gameLocal.random.RandomFloat() * idMath::TWO_PI;
	c = cos( a );
	s = -sin( a );
	
	axis[2] = -dir;
	axis[2].Normalize();
	axis[2].NormalVectors( axistemp[0], axistemp[1] );
	axis[0] = axistemp[ 0 ] * c + axistemp[ 1 ] * s;
	axis[1] = axistemp[ 0 ] * s + axistemp[ 1 ] * -c;
	
	textureAxis[0] = axis[0] * ( 1.0f / decalSize );
	textureAxis[0][3] = -( point * textureAxis[0].Normal() ) + 0.5f;
	
	textureAxis[1] = axis[1] * ( 1.0f / decalSize );
	textureAxis[1][3] = -( point * textureAxis[1].Normal() ) + 0.5f;
	
	for( i = 0; i < shards.Num(); i++ )
	{
		idFixedWinding& winding = shards[i]->winding;
		origin = shards[i]->clipModel->GetOrigin();
		axis = shards[i]->clipModel->GetAxis();
		float d0, d1;
		
		clipBits = -1;
		for( j = 0; j < winding.GetNumPoints(); j++ )
		{
			idVec3 p = origin + winding[j].ToVec3() * axis;
			
			st[j].x = d0 = textureAxis[0].Distance( p );
			st[j].y = d1 = textureAxis[1].Distance( p );
			
			bits = IEEE_FLT_SIGNBITSET( d0 );
			d0 = 1.0f - d0;
			bits |= IEEE_FLT_SIGNBITSET( d1 ) << 2;
			d1 = 1.0f - d1;
			bits |= IEEE_FLT_SIGNBITSET( d0 ) << 1;
			bits |= IEEE_FLT_SIGNBITSET( d1 ) << 3;
			
			clipBits &= bits;
		}
		
		if( clipBits )
		{
			continue;
		}
		
		idFixedWinding* decal = new( TAG_PARTICLE ) idFixedWinding;
		shards[i]->decals.Append( decal );
		
		decal->SetNumPoints( winding.GetNumPoints() );
		for( j = 0; j < winding.GetNumPoints(); j++ )
		{
			( *decal )[j].ToVec3() = winding[j].ToVec3();
			( *decal )[j].s = st[j].x;
			( *decal )[j].t = st[j].y;
		}
	}
	
	BecomeActive( TH_UPDATEVISUALS );
}

/*
================
idBrittleFracture::DropShard
================
*/
void idBrittleFracture::DropShard( shard_t* shard, const idVec3& point, const idVec3& dir, const float impulse, const int time )
{
	int i, j, clipModelId;
	float dist, f;
	idVec3 dir2, origin;
	idMat3 axis;
	shard_t* neighbour;
	
	// don't display decals on dropped shards
	shard->decals.DeleteContents( true );
	
	// remove neighbour pointers of neighbours pointing to this shard
	for( i = 0; i < shard->neighbours.Num(); i++ )
	{
		neighbour = shard->neighbours[i];
		for( j = 0; j < neighbour->neighbours.Num(); j++ )
		{
			if( neighbour->neighbours[j] == shard )
			{
				neighbour->neighbours.RemoveIndex( j );
				break;
			}
		}
	}
	
	// remove neighbour pointers
	shard->neighbours.Clear();
	
	// remove the clip model from the static physics object
	clipModelId = shard->clipModel->GetId();
	physicsObj.SetClipModel( NULL, 1.0f, clipModelId, false );
	
	origin = shard->clipModel->GetOrigin();
	axis = shard->clipModel->GetAxis();
	
	// set the dropped time for fading
	shard->droppedTime = time;
	
	dir2 = origin - point;
	dist = dir2.Normalize();
	f = dist > maxShatterRadius ? 1.0f : idMath::Sqrt( idMath::Fabs( dist - minShatterRadius ) ) * ( 1.0f / idMath::Sqrt( idMath::Fabs( maxShatterRadius - minShatterRadius ) ) );
	
	// setup the physics
	shard->physicsObj.SetSelf( this );
	shard->physicsObj.SetClipModel( shard->clipModel, density );
	shard->physicsObj.SetMass( shardMass );
	shard->physicsObj.SetOrigin( origin );
	shard->physicsObj.SetAxis( axis );
	shard->physicsObj.SetBouncyness( bouncyness );
	shard->physicsObj.SetFriction( 0.6f, 0.6f, friction );
	shard->physicsObj.SetGravity( gameLocal.GetGravity() );
	shard->physicsObj.SetContents( CONTENTS_RENDERMODEL );
	shard->physicsObj.SetClipMask( MASK_SOLID | CONTENTS_MOVEABLECLIP );
	shard->physicsObj.ApplyImpulse( 0, origin, impulse * linearVelocityScale * dir );
	shard->physicsObj.SetAngularVelocity( dir.Cross( dir2 ) * ( f * angularVelocityScale ) );
	
	shard->clipModel->SetId( clipModelId );
	
	BecomeActive( TH_PHYSICS );
}

/*
================
idBrittleFracture::Shatter
================
*/
void idBrittleFracture::Shatter( const idVec3& point, const idVec3& impulse, const int time )
{
	int i;
	idVec3 dir;
	shard_t* shard;
	float m;
	
	if( common->IsServer() )
	{
		idBitMsg	msg;
		byte		msgBuf[MAX_EVENT_PARAM_SIZE];
		
		msg.InitWrite( msgBuf, sizeof( msgBuf ) );
		msg.BeginWriting();
		msg.WriteFloat( point[0] );
		msg.WriteFloat( point[1] );
		msg.WriteFloat( point[2] );
		msg.WriteFloat( impulse[0] );
		msg.WriteFloat( impulse[1] );
		msg.WriteFloat( impulse[2] );
		ServerSendEvent( EVENT_SHATTER, &msg, true );
	}
	
	// Store off the event so we can rebuilt the object if we reload a savegame
	fractureEvent_s fractureEvent;
	fractureEvent.eventType = EVENT_SHATTER;
	fractureEvent.point = point;
	fractureEvent.vector = impulse;
	storedEvents.Append( fractureEvent );
	
	if( time > ( gameLocal.time - SHARD_ALIVE_TIME ) )
	{
		StartSound( "snd_shatter", SND_CHANNEL_ANY, 0, false, NULL );
	}
	
	if( !IsBroken() )
	{
		Break();
	}
	
	if( fxFracture.Length() )
	{
		idEntityFx::StartFx( fxFracture, &point, &GetPhysics()->GetAxis(), this, true );
	}
	
	dir = impulse;
	m = dir.Normalize();
	
	for( i = 0; i < shards.Num(); i++ )
	{
		shard = shards[i];
		
		if( shard->droppedTime != -1 )
		{
			continue;
		}
		
		if( ( shard->clipModel->GetOrigin() - point ).LengthSqr() > Square( maxShatterRadius ) )
		{
			continue;
		}
		
		DropShard( shard, point, dir, m, time );
	}
	
	DropFloatingIslands( point, impulse, time );
}

/*
================
idBrittleFracture::DropFloatingIslands
================
*/
void idBrittleFracture::DropFloatingIslands( const idVec3& point, const idVec3& impulse, const int time )
{
	int i, j, numIslands;
	int queueStart, queueEnd;
	shard_t* curShard, *nextShard, **queue;
	bool touchesEdge;
	idVec3 dir;
	
	dir = impulse;
	dir.Normalize();
	
	numIslands = 0;
	queue = ( shard_t** ) _alloca16( shards.Num() * sizeof( shard_t** ) );
	for( i = 0; i < shards.Num(); i++ )
	{
		shards[i]->islandNum = 0;
	}
	
	for( i = 0; i < shards.Num(); i++ )
	{
	
		if( shards[i]->droppedTime != -1 )
		{
			continue;
		}
		
		if( shards[i]->islandNum )
		{
			continue;
		}
		
		queueStart = 0;
		queueEnd = 1;
		queue[0] = shards[i];
		shards[i]->islandNum = numIslands + 1;
		touchesEdge = false;
		
		if( shards[i]->atEdge )
		{
			touchesEdge = true;
		}
		
		for( curShard = queue[queueStart]; queueStart < queueEnd; curShard = queue[++queueStart] )
		{
		
			for( j = 0; j < curShard->neighbours.Num(); j++ )
			{
			
				nextShard = curShard->neighbours[j];
				
				if( nextShard->droppedTime != -1 )
				{
					continue;
				}
				
				if( nextShard->islandNum )
				{
					continue;
				}
				
				queue[queueEnd++] = nextShard;
				nextShard->islandNum = numIslands + 1;
				
				if( nextShard->atEdge )
				{
					touchesEdge = true;
				}
			}
		}
		numIslands++;
		
		// if the island is not connected to the world at any edges
		if( !touchesEdge )
		{
			for( j = 0; j < queueEnd; j++ )
			{
				DropShard( queue[j], point, dir, 0.0f, time );
			}
		}
	}
}

/*
================
idBrittleFracture::Break
================
*/
void idBrittleFracture::Break()
{
	fl.takedamage = false;
	physicsObj.SetContents( CONTENTS_RENDERMODEL | CONTENTS_TRIGGER );
}

/*
================
idBrittleFracture::IsBroken
================
*/
bool idBrittleFracture::IsBroken() const
{
	return ( fl.takedamage == false );
}

/*
================
idBrittleFracture::Killed
================
*/
void idBrittleFracture::Killed( idEntity* inflictor, idEntity* attacker, int damage, const idVec3& dir, int location )
{
	if( !disableFracture )
	{
		ActivateTargets( this );
		Break();
	}
}

/*
================
idBrittleFracture::AddDamageEffect
================
*/
void idBrittleFracture::AddDamageEffect( const trace_t& collision, const idVec3& velocity, const char* damageDefName )
{
	if( !disableFracture )
	{
		ProjectDecal( collision.c.point, collision.c.normal, gameLocal.time, damageDefName );
	}
}

static float fractureSplitTable[] = { 1365.123f, 5.324f, 1125.34f, 50.34f, 555.252f, 100.12f, 230.53f, 10000.87f, 10000.87f  };

/*
================
idBrittleFracture::Fracture_r
================
*/
void idBrittleFracture::Fracture_r( idFixedWinding& w, idRandom2& random )
{
	int i, j, bestPlane;
	float a, c, s, dist, bestDist;
	idVec3 origin;
	idPlane windingPlane, splitPlanes[2];
	idMat3 axis, axistemp;
	idFixedWinding back;
	idTraceModel trm;
	idClipModel* clipModel;
	
	
	while( 1 )
	{
		origin = w.GetCenter();
		w.GetPlane( windingPlane );
		
		if( w.GetArea() < maxShardArea )
		{
			break;
		}
		
		// randomly create a split plane
		axis[2] = windingPlane.Normal();
		if( isXraySurface )
		{
			a = idMath::TWO_PI / 2.f;
		}
		else
		{
			a = random.RandomFloat() * idMath::TWO_PI;
		}
		c = cos( a );
		s = -sin( a );
		axis[2].NormalVectors( axistemp[0], axistemp[1] );
		axis[0] = axistemp[ 0 ] * c + axistemp[ 1 ] * s;
		axis[1] = axistemp[ 0 ] * s + axistemp[ 1 ] * -c;
		
		// get the best split plane
		bestDist = 0.0f;
		bestPlane = 0;
		for( i = 0; i < 2; i++ )
		{
			splitPlanes[i].SetNormal( axis[i] );
			splitPlanes[i].FitThroughPoint( origin );
			for( j = 0; j < w.GetNumPoints(); j++ )
			{
				dist = splitPlanes[i].Distance( w[j].ToVec3() );
				if( dist > bestDist )
				{
					bestDist = dist;
					bestPlane = i;
				}
			}
		}
		
		// split the winding
		if( !w.Split( &back, splitPlanes[bestPlane] ) )
		{
			break;
		}
		
		// recursively create shards for the back winding
		Fracture_r( back, random );
	}
	
	// translate the winding to it's center
	origin = w.GetCenter();
	for( j = 0; j < w.GetNumPoints(); j++ )
	{
		w[j].ToVec3() -= origin;
	}
	w.RemoveEqualPoints();
	
	trm.SetupPolygon( w );
	trm.Shrink( CM_CLIP_EPSILON );
	clipModel = new( TAG_PHYSICS ) idClipModel( trm, false );
	
	physicsObj.SetClipModel( clipModel, 1.0f, shards.Num() );
	physicsObj.SetOrigin( GetPhysics()->GetOrigin() + origin, shards.Num() );
	physicsObj.SetAxis( GetPhysics()->GetAxis(), shards.Num() );
	
	AddShard( clipModel, w );
}

/*
================
CompareVec5
================
*/
bool CompareVec5( const idVec5& v0, const idVec5& v1 )
{
	float dx = v0.x - v1.x;
	float dy = v0.y - v1.y;
	float dz = v0.z - v1.z;
	float ds = v0.s - v1.s;
	float dt = v0.t - v1.t;
	float d = ( dx * dx ) + ( dy * dy ) + ( dz * dz ) + ( ds * ds ) + ( dt + dt );
	return ( d == 0.0f );
}

/*
================
idBrittleFracture::CreateFractures
================
*/
void idBrittleFracture::CreateFractures( const idRenderModel* renderModel )
{
	if( !renderModel || renderModel->NumSurfaces() < 1 )
	{
		return;
	}
	
	physicsObj.SetSelf( this );
	physicsObj.SetOrigin( GetPhysics()->GetOrigin(), 0 );
	physicsObj.SetAxis( GetPhysics()->GetAxis(), 0 );
	
	const modelSurface_t* surf = renderModel->Surface( 0 );
	material = surf->shader;
	
	idMat3 physAxis;
	physAxis = physicsObj.GetAxis();
	if( isXraySurface )
	{
		idFixedWinding w;
		
		for( int i = 0; i < 4; i++ )
		{
			const idDrawVert* v = &surf->geometry->verts[i];
			w.AddPoint( idVec5( v->xyz, v->GetTexCoord() ) );
		}
		
		idRandom2 random( entityNumber );
		Fracture_r( w , random );
		
	}
	else
	{
		const idDrawVert* verts = surf->geometry->verts;
		triIndex_t* indexes = surf->geometry->indexes;
		
		for( int j = 0; j < surf->geometry->numIndexes; j += 3 )
		{
			int i0 = indexes[ j + 0 ];
			int i1 = indexes[ j + 1 ];
			int i2 = indexes[ j + 2 ];
			idFixedWinding w;
			w.AddPoint( idVec5( verts[i2].xyz, verts[i2].GetTexCoord() ) );
			w.AddPoint( idVec5( verts[i1].xyz, verts[i1].GetTexCoord() ) );
			w.AddPoint( idVec5( verts[i0].xyz, verts[i0].GetTexCoord() ) );
			idPlane p1;
			w.GetPlane( p1 );
			for( int k = j + 3; k < surf->geometry->numIndexes && ( w.GetNumPoints() + 1 < MAX_POINTS_ON_WINDING ); k += 3 )
			{
				int i3 = indexes[ k + 0 ];
				int i4 = indexes[ k + 1 ];
				int i5 = indexes[ k + 2 ];
				idFixedWinding w2;
				w2.AddPoint( idVec5( verts[i5].xyz, verts[i5].GetTexCoord() ) );
				w2.AddPoint( idVec5( verts[i4].xyz, verts[i4].GetTexCoord() ) );
				w2.AddPoint( idVec5( verts[i3].xyz, verts[i3].GetTexCoord() ) );
				idPlane p2;
				w2.GetPlane( p2 );
				if( p1 != p2 )
				{
					break;
				}
				bool found = false;
				for( int w1i = 0; w1i < w.GetNumPoints(); w1i++ )
				{
					for( int w2i = 0; w2i < w2.GetNumPoints(); w2i++ )
					{
						if( CompareVec5( w[w1i], w2[w2i] ) && CompareVec5( w[( w1i + 1 ) % w.GetNumPoints()], w2[( w2i + 2 ) % w2.GetNumPoints()] ) )
						{
							w.InsertPoint( w2[( w2i + 1 ) % w2.GetNumPoints()], ( w1i + 1 ) % w.GetNumPoints() );
							j = k;
							found = true;
							break;
						}
					}
					if( found )
					{
						break;
					}
				}
				if( !found )
				{
					break;
				}
			}
			
			idRandom2 random( entityNumber );
			Fracture_r( w, random );
		}
	}
	
	
	physicsObj.SetContents( material->GetContentFlags() );
	SetPhysics( &physicsObj );
}

/*
================
idBrittleFracture::FindNeighbours
================
*/
void idBrittleFracture::FindNeighbours()
{
	int i, j, k, l;
	idVec3 p1, p2, dir;
	idMat3 axis;
	idPlane plane[4];
	
	for( i = 0; i < shards.Num(); i++ )
	{
	
		shard_t* shard1 = shards[i];
		const idWinding& w1 = shard1->winding;
		const idVec3& origin1 = shard1->clipModel->GetOrigin();
		const idMat3& axis1 = shard1->clipModel->GetAxis();
		
		for( k = 0; k < w1.GetNumPoints(); k++ )
		{
		
			p1 = origin1 + w1[k].ToVec3() * axis1;
			p2 = origin1 + w1[( k + 1 ) % w1.GetNumPoints()].ToVec3() * axis1;
			dir = p2 - p1;
			dir.Normalize();
			axis = dir.ToMat3();
			
			plane[0].SetNormal( dir );
			plane[0].FitThroughPoint( p1 );
			plane[1].SetNormal( -dir );
			plane[1].FitThroughPoint( p2 );
			plane[2].SetNormal( axis[1] );
			plane[2].FitThroughPoint( p1 );
			plane[3].SetNormal( axis[2] );
			plane[3].FitThroughPoint( p1 );
			
			for( j = 0; j < shards.Num(); j++ )
			{
			
				if( i == j )
				{
					continue;
				}
				
				shard_t* shard2 = shards[j];
				
				for( l = 0; l < shard1->neighbours.Num(); l++ )
				{
					if( shard1->neighbours[l] == shard2 )
					{
						break;
					}
				}
				if( l < shard1->neighbours.Num() )
				{
					continue;
				}
				
				const idWinding& w2 = shard2->winding;
				const idVec3& origin2 = shard2->clipModel->GetOrigin();
				const idMat3& axis2 = shard2->clipModel->GetAxis();
				
				for( l = w2.GetNumPoints() - 1; l >= 0; l-- )
				{
					p1 = origin2 + w2[l].ToVec3() * axis2;
					p2 = origin2 + w2[( l - 1 + w2.GetNumPoints() ) % w2.GetNumPoints()].ToVec3() * axis2;
					if( plane[0].Side( p2, 0.1f ) == SIDE_FRONT && plane[1].Side( p1, 0.1f ) == SIDE_FRONT )
					{
						if( plane[2].Side( p1, 0.1f ) == SIDE_ON && plane[3].Side( p1, 0.1f ) == SIDE_ON )
						{
							if( plane[2].Side( p2, 0.1f ) == SIDE_ON && plane[3].Side( p2, 0.1f ) == SIDE_ON )
							{
								shard1->neighbours.Append( shard2 );
								shard1->edgeHasNeighbour[k] = true;
								shard2->neighbours.Append( shard1 );
								shard2->edgeHasNeighbour[( l - 1 + w2.GetNumPoints() ) % w2.GetNumPoints()] = true;
								break;
							}
						}
					}
				}
			}
		}
		
		for( k = 0; k < w1.GetNumPoints(); k++ )
		{
			if( !shard1->edgeHasNeighbour[k] )
			{
				break;
			}
		}
		if( k < w1.GetNumPoints() )
		{
			shard1->atEdge = true;
		}
		else
		{
			shard1->atEdge = false;
		}
	}
}

/*
================
idBrittleFracture::Event_Activate
================
*/
void idBrittleFracture::Event_Activate( idEntity* activator )
{
	disableFracture = false;
	if( health <= 0 )
	{
		Break();
	}
}

/*
================
idBrittleFracture::Event_Touch
================
*/
void idBrittleFracture::Event_Touch( idEntity* other, trace_t* trace )
{
	idVec3 point, impulse;
	
	// Let the server handle this, clients dont' predict it
	if( common->IsClient() )
	{
		return;
	}
	
	if( !IsBroken() )
	{
		return;
	}
	
	if( trace->c.id < 0 || trace->c.id >= shards.Num() )
	{
		return;
	}
	
	point = shards[trace->c.id]->clipModel->GetOrigin();
	impulse = other->GetPhysics()->GetLinearVelocity() * other->GetPhysics()->GetMass();
	
	Shatter( point, impulse, gameLocal.time );
}

/*
================
idBrittleFracture::ClientThink
================
*/
void idBrittleFracture::ClientThink( const int curTime, const float fraction, const bool predict )
{

	// only think forward because the state is not synced through snapshots
	if( !gameLocal.isNewFrame )
	{
		return;
	}
	
	Think();
}

/*
================
idBrittleFracture::ClientPredictionThink
================
*/
void idBrittleFracture::ClientPredictionThink()
{
	// only think forward because the state is not synced through snapshots
	if( !gameLocal.isNewFrame )
	{
		return;
	}
	
	Think();
}

/*
================
idBrittleFracture::ClientReceiveEvent
================
*/
bool idBrittleFracture::ClientReceiveEvent( int event, int time, const idBitMsg& msg )
{
	idVec3 point, dir;
	
	switch( event )
	{
		case EVENT_PROJECT_DECAL:
		{
			point[0] = msg.ReadFloat();
			point[1] = msg.ReadFloat();
			point[2] = msg.ReadFloat();
			dir[0] = msg.ReadFloat();
			dir[1] = msg.ReadFloat();
			dir[2] = msg.ReadFloat();
			ProjectDecal( point, dir, time, NULL );
			return true;
		}
		case EVENT_SHATTER:
		{
			point[0] = msg.ReadFloat();
			point[1] = msg.ReadFloat();
			point[2] = msg.ReadFloat();
			dir[0] = msg.ReadFloat();
			dir[1] = msg.ReadFloat();
			dir[2] = msg.ReadFloat();
			Shatter( point, dir, time );
			return true;
		}
		default:
		{
			return idEntity::ClientReceiveEvent( event, time, msg );
		}
	}
}