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

Wolfenstein: Enemy Territory GPL Source Code
Copyright (C) 1999-2010 id Software LLC, a ZeniMax Media company. 

This file is part of the Wolfenstein: Enemy Territory GPL Source Code (“Wolf ET Source Code”).  

Wolf ET 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.

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

In addition, the Wolf: ET 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 Wolf ET 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.

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

// cg_marks.c -- wall marks

#include "cg_local.h"

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

MARK POLYS

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


markPoly_t cg_activeMarkPolys;          // double linked list
markPoly_t  *cg_freeMarkPolys;          // single linked list
markPoly_t cg_markPolys[MAX_MARK_POLYS];

/*
===================
CG_InitMarkPolys

This is called at startup and for tournement restarts
===================
*/
void    CG_InitMarkPolys( void ) {
	int i;
	markPoly_t *trav, *lasttrav;

	memset( cg_markPolys, 0, sizeof( cg_markPolys ) );

	cg_activeMarkPolys.nextMark = &cg_activeMarkPolys;
	cg_activeMarkPolys.prevMark = &cg_activeMarkPolys;
	cg_freeMarkPolys = cg_markPolys;
	for ( i = 0, trav = cg_markPolys + 1, lasttrav = cg_markPolys ; i < MAX_MARK_POLYS - 1 ; i++, trav++ ) {
		lasttrav->nextMark = trav;
		lasttrav = trav;
	}
}


/*
==================
CG_FreeMarkPoly
==================
*/
void CG_FreeMarkPoly( markPoly_t *le ) {
	if ( !le->prevMark ) {
		CG_Error( "CG_FreeLocalEntity: not active" );
	}

	// remove from the doubly linked active list
	le->prevMark->nextMark = le->nextMark;
	le->nextMark->prevMark = le->prevMark;

	// the free list is only singly linked
	le->nextMark = cg_freeMarkPolys;
	cg_freeMarkPolys = le;
}

/*
===================
CG_AllocMark

Will allways succeed, even if it requires freeing an old active mark
===================
*/
markPoly_t  *CG_AllocMark( int endTime ) {
	markPoly_t  *le; //, *trav, *lastTrav;
	int time;

	if ( !cg_freeMarkPolys ) {
		// no free entities, so free the one at the end of the chain
		// remove the oldest active entity
		time = cg_activeMarkPolys.prevMark->time;
		while ( cg_activeMarkPolys.prevMark && time == cg_activeMarkPolys.prevMark->time ) {
			CG_FreeMarkPoly( cg_activeMarkPolys.prevMark );
		}
	}

	le = cg_freeMarkPolys;
	cg_freeMarkPolys = cg_freeMarkPolys->nextMark;

	memset( le, 0, sizeof( *le ) );

	// Ridah, TODO: sort this, so the list is always sorted by longest duration -> shortest duration,
	// this way the shortest duration mark will always get overwritten first
	//for (trav = cg_activeMarkPolys.nextMark; (trav->duration + trav->time > endTime) && (trav != cg_activeMarkPolys.prevMark) ; lastTrav = trav, trav++ ) {
	// Respect the FOR loop
	//}

	// link into the active list
	le->nextMark = cg_activeMarkPolys.nextMark;
	le->prevMark = &cg_activeMarkPolys;
	cg_activeMarkPolys.nextMark->prevMark = le;
	cg_activeMarkPolys.nextMark = le;
	return le;
}



/*
CG_ImpactMark()
projection is a normal and distance (not a plane, but rather how far to project)
it MUST be normalized!
if lifeTime < 0, then generate a temporary mark
*/

// Ridah, increased this since we leave them around for longer
#define MAX_MARK_FRAGMENTS  384
#define MAX_MARK_POINTS     1024
//#define	MAX_MARK_FRAGMENTS	128
//#define	MAX_MARK_POINTS		384

// these are ignored now for the most part
//#define	MARK_TOTAL_TIME		20000	// (SA) made this a cvar: cg_markTime  (we could cap the time or remove marks quicker if too long a time starts to cause new marks to not appear)
#define MARK_FADE_TIME      10000

// comment out to use old-style mark code
#define YDNAR_DECAL_MARKS

void CG_ImpactMark( qhandle_t markShader, vec3_t origin, vec4_t projection, float radius, float orientation, float r, float g, float b, float a, int lifeTime )
#ifdef YDNAR_DECAL_MARKS
{
	int i;
	vec3_t pushedOrigin, axis[ 3 ];
	vec4_t color;
	int fadeTime;
	vec3_t points[ 4 ];


	/* early out */
	if ( lifeTime == 0 ) {
		return;
	}

	/* set projection (inverse of dir) */
	//%	VectorSubtract( vec3_origin, dir, projection );
	//%	VectorNormalize( projection );
	//%	projection[ 3 ] = radius * 8;

	/* make rotated polygon axis */
	VectorCopy( projection, axis[ 0 ] );
	PerpendicularVector( axis[ 1 ], axis[ 0 ] );
	RotatePointAroundVector( axis[ 2 ], axis[ 0 ], axis[ 1 ], -orientation );
	CrossProduct( axis[ 0 ], axis[ 2 ], axis[ 1 ] );

	/* push the origin out a bit */
	VectorMA( origin, -1.0f, axis[ 0 ], pushedOrigin );

	/* create the full polygon */
	for ( i = 0; i < 3; i++ )
	{
		/* old */
		//%	points[ 0 ][ i ] = pushedOrigin[ i ] - radius * axis[ 1 ][ i ] - radius * axis[ 2 ][ i ];
		//%	points[ 1 ][ i ] = pushedOrigin[ i ] + radius * axis[ 1 ][ i ] - radius * axis[ 2 ][ i ];
		//%	points[ 2 ][ i ] = pushedOrigin[ i ] + radius * axis[ 1 ][ i ] + radius * axis[ 2 ][ i ];
		//%	points[ 3 ][ i ] = pushedOrigin[ i ] - radius * axis[ 1 ][ i ] + radius * axis[ 2 ][ i ];

		/* new */
		points[ 0 ][ i ] = pushedOrigin[ i ] - radius * axis[ 1 ][ i ] - radius * axis[ 2 ][ i ];
		points[ 1 ][ i ] = pushedOrigin[ i ] - radius * axis[ 1 ][ i ] + radius * axis[ 2 ][ i ];
		points[ 2 ][ i ] = pushedOrigin[ i ] + radius * axis[ 1 ][ i ] + radius * axis[ 2 ][ i ];
		points[ 3 ][ i ] = pushedOrigin[ i ] + radius * axis[ 1 ][ i ] - radius * axis[ 2 ][ i ];
	}

	/* debug code */
	#if 0
	VectorSet( points[ 0 ], origin[ 0 ] - radius, origin[ 1 ] - radius, origin[ 2 ] );
	VectorSet( points[ 1 ], origin[ 0 ] - radius, origin[ 1 ] + radius, origin[ 2 ] );
	VectorSet( points[ 2 ], origin[ 0 ] + radius, origin[ 1 ] + radius, origin[ 2 ] );
	VectorSet( points[ 3 ], origin[ 0 ] + radius, origin[ 1 ] - radius, origin[ 2 ] );
	CG_Printf( "Dir: %f %f %f\n", dir[ 0 ], dir[ 1 ], dir[ 2 ] );
	#endif

	/* set color */
	color[ 0 ] = r;
	color[ 1 ] = g;
	color[ 2 ] = b;
	color[ 3 ] = a;

	/* set decal times (in seconds) */
	fadeTime = lifeTime >> 4;

	/* add the decal */
	trap_R_ProjectDecal( markShader, 4, points, projection, color, lifeTime, fadeTime );
}
#else
{
	vec3_t axis[3];
	float texCoordScale;
	vec3_t originalPoints[4];
	byte colors[4];
	int i, j;
	int numFragments;
	markFragment_t markFragments[MAX_MARK_FRAGMENTS], *mf;
	vec5_t markPoints[MAX_MARK_POINTS];             // Ridah, made it vec5_t so it includes S/T
	vec3_t projection;
	int multMaxFragments = 1;

	if ( !cg_markTime.integer ) {
		return;
	}

	if ( radius <= 0 ) {
		return;
	}

	if ( temporary ) {
		if ( CG_CullPointAndRadius( origin, radius ) ) {
			return;
		}
	}

	// Ridah, if no duration, use the default
	if ( duration < 0 ) {
		if ( duration == -2 ) {
			multMaxFragments = -1;  // use original mapping
		}

//		duration = MARK_TOTAL_TIME;
		duration = cg_markTime.integer;
	}

	// create the texture axis
	VectorNormalize2( dir, axis[0] );
	PerpendicularVector( axis[1], axis[0] );
	RotatePointAroundVector( axis[2], axis[0], axis[1], orientation );
	CrossProduct( axis[0], axis[2], axis[1] );

	texCoordScale = 0.5 * 1.0 / radius;

	// create the full polygon
	for ( i = 0 ; i < 3 ; i++ ) {
		originalPoints[0][i] = origin[i] - radius * axis[1][i] - radius * axis[2][i];
		originalPoints[1][i] = origin[i] + radius * axis[1][i] - radius * axis[2][i];
		originalPoints[2][i] = origin[i] + radius * axis[1][i] + radius * axis[2][i];
		originalPoints[3][i] = origin[i] - radius * axis[1][i] + radius * axis[2][i];
	}

	// get the fragments
	//VectorScale( dir, -20, projection );
	VectorScale( dir, radius * 2, projection );
	numFragments = trap_CM_MarkFragments( (int)orientation, (void *)originalPoints,
										  projection, MAX_MARK_POINTS, (float *)&markPoints[0],
										  MAX_MARK_FRAGMENTS * multMaxFragments, markFragments );

	colors[0] = red * 255;
	colors[1] = green * 255;
	colors[2] = blue * 255;
	colors[3] = alpha * 255;

	for ( i = 0, mf = markFragments ; i < numFragments ; i++, mf++ ) {
		polyVert_t  *v;
		polyVert_t verts[MAX_VERTS_ON_POLY];
		markPoly_t  *mark;
		qboolean hasST;

		// we have an upper limit on the complexity of polygons
		// that we store persistantly
		if ( mf->numPoints > MAX_VERTS_ON_POLY ) {
			mf->numPoints = MAX_VERTS_ON_POLY;
		}
		if ( mf->numPoints < 0 ) {
			hasST = qtrue;
			mf->numPoints *= -1;
		} else {
			hasST = qfalse;
		}
		for ( j = 0, v = verts ; j < mf->numPoints ; j++, v++ ) {
			vec3_t delta;

			VectorCopy( markPoints[mf->firstPoint + j], v->xyz );

			if ( !hasST ) {
				VectorSubtract( v->xyz, origin, delta );
				v->st[0] = 0.5 + DotProduct( delta, axis[1] ) * texCoordScale;
				v->st[1] = 0.5 + DotProduct( delta, axis[2] ) * texCoordScale;
			} else {
				v->st[0] = markPoints[mf->firstPoint + j][3];
				v->st[1] = markPoints[mf->firstPoint + j][4];
			}

			*(int *)v->modulate = *(int *)colors;
		}

		// if it is a temporary (shadow) mark, add it immediately and forget about it
		if ( temporary ) {
			trap_R_AddPolyToScene( markShader, mf->numPoints, verts );
			continue;
		}

		// otherwise save it persistantly
		mark = CG_AllocMark( cg.time + duration );
		mark->time = cg.time;
		mark->alphaFade = alphaFade;
		mark->markShader = markShader;
		mark->poly.numVerts = mf->numPoints;
		mark->color[0] = red;
		mark->color[1] = green;
		mark->color[2] = blue;
		mark->color[3] = alpha;
		mark->duration = duration;
		memcpy( mark->verts, verts, mf->numPoints * sizeof( verts[0] ) );
	}
}
#endif



/*
===============
CG_AddMarks
===============
*/

void CG_AddMarks( void ) {
	int j;
	markPoly_t  *mp, *next;
	int t;
	int fade;

	if ( !cg_markTime.integer ) {
		return;
	}

	mp = cg_activeMarkPolys.nextMark;
	for ( ; mp != &cg_activeMarkPolys ; mp = next ) {
		// grab next now, so if the local entity is freed we
		// still have it
		next = mp->nextMark;

		// see if it is time to completely remove it
		if ( cg.time > mp->time + mp->duration ) {
			CG_FreeMarkPoly( mp );
			continue;
		}

		// fade all marks out with time
		t = mp->time + mp->duration - cg.time;
		if ( t < (float)mp->duration / 2.0 ) {
			fade = (int)( 255.0 * (float)t / ( (float)mp->duration / 2.0 ) );
			if ( mp->alphaFade ) {
				for ( j = 0 ; j < mp->poly.numVerts ; j++ ) {
					mp->verts[j].modulate[3] = fade;
				}
			} else {
				for ( j = 0 ; j < mp->poly.numVerts ; j++ ) {
					mp->verts[j].modulate[0] = mp->color[0] * fade;
					mp->verts[j].modulate[1] = mp->color[1] * fade;
					mp->verts[j].modulate[2] = mp->color[2] * fade;
				}
			}
		}

		trap_R_AddPolyToScene( mp->markShader, mp->poly.numVerts, mp->verts );
	}
}