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fteqw/engine/gl/gl_warp.c
Spoike 3cd3e0a025 water warp stuff for proper q2 transparency support. 
git-svn-id: https://svn.code.sf.net/p/fteqw/code/trunk@138 fc73d0e0-1445-4013-8a0c-d673dee63da5
2004-09-04 18:08:51 +00:00

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/*
Copyright (C) 1996-1997 Id Software, Inc.
This program 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 2
of the License, or (at your option) any later version.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
// gl_warp.c -- sky and water polygons
#include "quakedef.h"
#include "glquake.h"
extern model_t *loadmodel;
int skytexturenum;
int solidskytexture;
int alphaskytexture;
float speedscale; // for top sky and bottom sky
qboolean usingskybox;
msurface_t *warpface;
extern cvar_t gl_skyboxname;
extern cvar_t gl_waterripples;
char loadedskybox[256];
void R_DrawSkyBox (msurface_t *s);
void BoundPoly (int numverts, float *verts, vec3_t mins, vec3_t maxs)
{
int i, j;
float *v;
mins[0] = mins[1] = mins[2] = 9999;
maxs[0] = maxs[1] = maxs[2] = -9999;
v = verts;
for (i=0 ; i<numverts ; i++)
for (j=0 ; j<3 ; j++, v++)
{
if (*v < mins[j])
mins[j] = *v;
if (*v > maxs[j])
maxs[j] = *v;
}
}
void SubdividePolygon (int numverts, float *verts, float dividesize)
{
int i, j, k;
vec3_t mins, maxs;
float m;
float *v;
vec3_t front[64], back[64];
int f, b;
float dist[64];
float frac;
glpoly_t *poly;
float s, t;
if (numverts > 60 || numverts <= 0)
Sys_Error ("numverts = %i", numverts);
BoundPoly (numverts, verts, mins, maxs);
for (i=0 ; i<3 ; i++)
{
m = (mins[i] + maxs[i]) * 0.5;
m = dividesize * floor (m/dividesize + 0.5);
if (maxs[i] - m < 8)
continue;
if (m - mins[i] < 8)
continue;
// cut it
v = verts + i;
for (j=0 ; j<numverts ; j++, v+= 3)
dist[j] = *v - m;
// wrap cases
dist[j] = dist[0];
v-=i;
VectorCopy (verts, v);
f = b = 0;
v = verts;
for (j=0 ; j<numverts ; j++, v+= 3)
{
if (dist[j] >= 0)
{
VectorCopy (v, front[f]);
f++;
}
if (dist[j] <= 0)
{
VectorCopy (v, back[b]);
b++;
}
if (dist[j] == 0 || dist[j+1] == 0)
continue;
if ( (dist[j] > 0) != (dist[j+1] > 0) )
{
// clip point
frac = dist[j] / (dist[j] - dist[j+1]);
for (k=0 ; k<3 ; k++)
front[f][k] = back[b][k] = v[k] + frac*(v[3+k] - v[k]);
f++;
b++;
}
}
SubdividePolygon (f, front[0], dividesize);
SubdividePolygon (b, back[0], dividesize);
return;
}
poly = Hunk_AllocName (sizeof(glpoly_t) + (numverts-4) * VERTEXSIZE*sizeof(float), "subpoly");
poly->next = warpface->polys;
warpface->polys = poly;
poly->numverts = numverts;
for (i=0 ; i<numverts ; i++, verts+= 3)
{
VectorCopy (verts, poly->verts[i]);
s = DotProduct (verts, warpface->texinfo->vecs[0]);
t = DotProduct (verts, warpface->texinfo->vecs[1]);
poly->verts[i][3] = s;
poly->verts[i][4] = t;
}
}
/*
================
GL_SubdivideSurface
Breaks a polygon up along axial 64 unit
boundaries so that turbulent and sky warps
can be done reasonably.
================
*/
void GL_SubdivideSurface (msurface_t *fa, float dividesize)
{
vec3_t verts[64];
int numverts;
int i;
int lindex;
float *vec;
warpface = fa;
//
// convert edges back to a normal polygon
//
numverts = 0;
for (i=0 ; i<fa->numedges ; i++)
{
lindex = loadmodel->surfedges[fa->firstedge + i];
if (lindex > 0)
vec = loadmodel->vertexes[loadmodel->edges[lindex].v[0]].position;
else
vec = loadmodel->vertexes[loadmodel->edges[-lindex].v[1]].position;
VectorCopy (vec, verts[numverts]);
numverts++;
if(numverts >= 64)
{
Con_Printf("Too many verts on surface\n");
break;
}
}
SubdividePolygon (numverts, verts[0], dividesize);
}
//=========================================================
// speed up sin calculations - Ed
float turbsin[] =
{
#include "gl_warp_sin.h"
};
#define TURBSCALE (256.0 / (2 * M_PI))
/*
=============
EmitWaterPolys
Does a water warp on the pre-fragmented glpoly_t chain
=============
*/
void EmitWaterPolys (msurface_t *fa, float basealpha)
{
glpoly_t *p;
float *v;
int i;
float s, t, os, ot;
#ifdef WATERLAYERS
extern cvar_t r_waterlayers;
if (gl_waterripples.value)
{
float f = 10;
glEnable(GL_AUTO_NORMAL);
for (p=fa->polys ; p ; p=p->next)
{
glBegin (GL_POLYGON);
for (i=0,v=p->verts[0] ; i<p->numverts ; i++, v+=VERTEXSIZE)
{
os = v[3];
ot = v[4];
s = os + turbsin[(int)((ot*0.125+realtime) * TURBSCALE) & 255];
s *= (1.0/64);
t = ot + turbsin[(int)((os*0.125+realtime) * TURBSCALE) & 255];
t *= (1.0/64);
glNormal3f(fa->plane->normal[0] + (sin(realtime+v[0]/f+v[1]/f))/4, fa->plane->normal[1] +(sin(realtime-v[1]/f))/4, fa->plane->normal[2] + (sin(realtime+v[2]/f))/4);
glTexCoord2f (s, t);
glVertex3fv (v);
}
glEnd ();
}
glDisable(GL_AUTO_NORMAL);
}
else if (r_waterlayers.value>=1)
{
float a, stm, ttm;
int l;
glDisable(GL_ALPHA_TEST);
glEnable(GL_BLEND); //to ensure.
for (a=basealpha,l = 0; l < r_waterlayers.value; l++,a=a*4/6)
{
glColor4f(1, 1, 1, a);
stm =cos(l)/10;
ttm =sin(l)/10;
for (p=fa->polys ; p ; p=p->next)
{
glBegin (GL_POLYGON);
for (i=0,v=p->verts[0] ; i<p->numverts ; i++, v+=VERTEXSIZE)
{
os = v[3]/(l*0.5+0.2);
ot = v[4]/(l*0.5+0.2);
s = os + turbsin[(int)((ot*0.125+cl.time+l*8) * TURBSCALE) & 255];//*r_watersurfacewarp.value;
s *= (1.0/64);
t = ot + turbsin[(int)((os*0.125+cl.time+l*8) * TURBSCALE) & 255];//*r_watersurfacewarp.value;
t *= (1.0/64);
glTexCoord2f (s+cl.time*stm, t+cl.time*ttm);
glVertex3fv (v);
}
glEnd ();
}
}
}
else
{
#endif
for (p=fa->polys ; p ; p=p->next)
{
glBegin (GL_POLYGON);
for (i=0,v=p->verts[0] ; i<p->numverts ; i++, v+=VERTEXSIZE)
{
os = v[3];
ot = v[4];
s = os + turbsin[(int)((ot*0.125+realtime) * TURBSCALE) & 255];
s *= (1.0/64);
t = ot + turbsin[(int)((os*0.125+realtime) * TURBSCALE) & 255];
t *= (1.0/64);
glTexCoord2f (s, t);
glVertex3fv (v);
}
glEnd ();
}
#ifdef WATERLAYERS
}
#endif
}
/*
=============
EmitSkyPolys
=============
*/
void EmitSkyPolys (msurface_t *fa)
{
glpoly_t *p;
float *v;
int i;
float s, t;
vec3_t dir;
float length;
for (p=fa->polys ; p ; p=p->next)
{
glBegin (GL_POLYGON);
for (i=0,v=p->verts[0] ; i<p->numverts ; i++, v+=VERTEXSIZE)
{
VectorSubtract (v, r_origin, dir);
dir[2] *= 3; // flatten the sphere
length = dir[0]*dir[0] + dir[1]*dir[1] + dir[2]*dir[2];
length = sqrt (length);
length = 6*63/length;
dir[0] *= length;
dir[1] *= length;
s = (speedscale + dir[0]) * (1.0/128);
t = (speedscale + dir[1]) * (1.0/128);
glTexCoord2f (s, t);
glVertex3fv (v);
}
glEnd ();
}
}
/*
===============
EmitBothSkyLayers
Does a sky warp on the pre-fragmented glpoly_t chain
This will be called for brushmodels, the world
will have them chained together.
===============
*/
void EmitBothSkyLayers (msurface_t *fa)
{
GL_DisableMultitexture();
GL_Bind (solidskytexture);
speedscale = realtime*8;
speedscale -= (int)speedscale & ~127 ;
EmitSkyPolys (fa);
glEnable (GL_BLEND);
GL_Bind (alphaskytexture);
speedscale = realtime*16;
speedscale -= (int)speedscale & ~127 ;
EmitSkyPolys (fa);
glDisable (GL_BLEND);
}
/*
=================
R_DrawSkyChain
=================
*/
void R_DrawSkyBoxChain (msurface_t *s);
void R_DrawSkyChain (msurface_t *s)
{
msurface_t *fa;
if (usingskybox)
{
R_DrawSkyBoxChain(s);
return;
}
GL_DisableMultitexture();
// used when gl_texsort is on
GL_Bind(solidskytexture);
speedscale = realtime*8;
speedscale -= (int)speedscale & ~127 ;
for (fa=s ; fa ; fa=fa->texturechain)
EmitSkyPolys (fa);
glEnable (GL_BLEND);
GL_Bind (alphaskytexture);
speedscale = realtime*16;
speedscale -= (int)speedscale & ~127 ;
for (fa=s ; fa ; fa=fa->texturechain)
EmitSkyPolys (fa);
glDisable (GL_BLEND);
}
/*
=================================================================
Quake 2 environment sky
=================================================================
*/
/*
==================
R_LoadSkys
==================
*/
static char *suf[6] = {"rt", "bk", "lf", "ft", "up", "dn"};
int skyboxtex[6];
void R_LoadSkys (void)
{
int i;
char name[64];
for (i=0 ; i<6 ; i++)
{
sprintf (name, "env/%s%s.tga", gl_skyboxname.string, suf[i]);
skyboxtex[i] = Mod_LoadHiResTexture(name, false, false);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
Q_strncpyz(loadedskybox, gl_skyboxname.string, sizeof(loadedskybox));
gl_skyboxname.modified = false;
}
qboolean GLR_CheckSky()
{
return true;
}
void GLR_SetSky(char *name, float rotate, vec3_t axis)
{
if (*name)
Cvar_Set(&gl_skyboxname, name);
}
vec3_t skyclip[6] = {
{1,1,0},
{1,-1,0},
{0,-1,1},
{0,1,1},
{1,0,1},
{-1,0,1}
};
int c_sky;
// 1 = s, 2 = t, 3 = 2048
int st_to_vec[6][3] =
{
{3,-1,2},
{-3,1,2},
{1,3,2},
{-1,-3,2},
{-2,-1,3}, // 0 degrees yaw, look straight up
{2,-1,-3} // look straight down
// {-1,2,3},
// {1,2,-3}
};
// s = [0]/[2], t = [1]/[2]
int vec_to_st[6][3] =
{
{-2,3,1},
{2,3,-1},
{1,3,2},
{-1,3,-2},
{-2,-1,3},
{-2,1,-3}
// {-1,2,3},
// {1,2,-3}
};
float skymins[2][6], skymaxs[2][6];
void DrawSkyPolygon (int nump, vec3_t vecs)
{
int i,j;
vec3_t v, av;
float s, t, dv;
int axis;
float *vp;
c_sky++;
#if 0
glBegin (GL_POLYGON);
for (i=0 ; i<nump ; i++, vecs+=3)
{
VectorAdd(vecs, r_origin, v);
glVertex3fv (v);
}
glEnd();
return;
#endif
// decide which face it maps to
VectorCopy (vec3_origin, v);
for (i=0, vp=vecs ; i<nump ; i++, vp+=3)
{
VectorAdd (vp, v, v);
}
av[0] = fabs(v[0]);
av[1] = fabs(v[1]);
av[2] = fabs(v[2]);
if (av[0] > av[1] && av[0] > av[2])
{
if (v[0] < 0)
axis = 1;
else
axis = 0;
}
else if (av[1] > av[2] && av[1] > av[0])
{
if (v[1] < 0)
axis = 3;
else
axis = 2;
}
else
{
if (v[2] < 0)
axis = 5;
else
axis = 4;
}
// project new texture coords
for (i=0 ; i<nump ; i++, vecs+=3)
{
j = vec_to_st[axis][2];
if (j > 0)
dv = vecs[j - 1];
else
dv = -vecs[-j - 1];
if (dv < 0.001)
continue; // don't divide by zero
j = vec_to_st[axis][0];
if (j < 0)
s = -vecs[-j -1] / dv;
else
s = vecs[j-1] / dv;
j = vec_to_st[axis][1];
if (j < 0)
t = -vecs[-j -1] / dv;
else
t = vecs[j-1] / dv;
if (s < skymins[0][axis])
skymins[0][axis] = s;
if (t < skymins[1][axis])
skymins[1][axis] = t;
if (s > skymaxs[0][axis])
skymaxs[0][axis] = s;
if (t > skymaxs[1][axis])
skymaxs[1][axis] = t;
}
}
#define MAX_CLIP_VERTS 64
void ClipSkyPolygon (int nump, vec3_t vecs, int stage)
{
float *norm;
float *v;
qboolean front, back;
float d, e;
float dists[MAX_CLIP_VERTS];
int sides[MAX_CLIP_VERTS];
vec3_t newv[2][MAX_CLIP_VERTS];
int newc[2];
int i, j;
if (nump > MAX_CLIP_VERTS-2)
Sys_Error ("ClipSkyPolygon: MAX_CLIP_VERTS");
if (stage == 6)
{ // fully clipped, so draw it
DrawSkyPolygon (nump, vecs);
return;
}
front = back = false;
norm = skyclip[stage];
for (i=0, v = vecs ; i<nump ; i++, v+=3)
{
d = DotProduct (v, norm);
if (d > ON_EPSILON)
{
front = true;
sides[i] = SIDE_FRONT;
}
else if (d < -ON_EPSILON)
{
back = true;
sides[i] = SIDE_BACK;
}
else
sides[i] = SIDE_ON;
dists[i] = d;
}
if (!front || !back)
{ // not clipped
ClipSkyPolygon (nump, vecs, stage+1);
return;
}
// clip it
sides[i] = sides[0];
dists[i] = dists[0];
VectorCopy (vecs, (vecs+(i*3)) );
newc[0] = newc[1] = 0;
for (i=0, v = vecs ; i<nump ; i++, v+=3)
{
switch (sides[i])
{
case SIDE_FRONT:
VectorCopy (v, newv[0][newc[0]]);
newc[0]++;
break;
case SIDE_BACK:
VectorCopy (v, newv[1][newc[1]]);
newc[1]++;
break;
case SIDE_ON:
VectorCopy (v, newv[0][newc[0]]);
newc[0]++;
VectorCopy (v, newv[1][newc[1]]);
newc[1]++;
break;
}
if (sides[i] == SIDE_ON || sides[i+1] == SIDE_ON || sides[i+1] == sides[i])
continue;
d = dists[i] / (dists[i] - dists[i+1]);
for (j=0 ; j<3 ; j++)
{
e = v[j] + d*(v[j+3] - v[j]);
newv[0][newc[0]][j] = e;
newv[1][newc[1]][j] = e;
}
newc[0]++;
newc[1]++;
}
// continue
ClipSkyPolygon (newc[0], newv[0][0], stage+1);
ClipSkyPolygon (newc[1], newv[1][0], stage+1);
}
/*
=================
R_DrawSkyChain
=================
*/
void R_DrawSkyBoxChain (msurface_t *s)
{
msurface_t *fa;
int i;
vec3_t verts[MAX_CLIP_VERTS];
glpoly_t *p;
c_sky = 0;
// GL_Bind(solidskytexture);
// calculate vertex values for sky box
for (fa=s ; fa ; fa=fa->texturechain)
{
for (p=fa->polys ; p ; p=p->next)
{
for (i=0 ; i<p->numverts ; i++)
{
VectorSubtract (p->verts[i], r_origin, verts[i]);
}
ClipSkyPolygon (p->numverts, verts[0], 0);
}
}
R_DrawSkyBox (s);
glColorMask(0, 0, 0, 0);
for (fa=s ; fa ; fa=fa->texturechain)
{
for (p=fa->polys ; p ; p=p->next)
{
glBegin(GL_POLYGON);
for (i = 0; i < p->numverts; i++)
glVertex3fv(p->verts[i]);
glEnd();
}
}
glColorMask(1, 1, 1, 1);
}
void R_AddSkySurface (msurface_t *fa)
{
int i;
vec3_t verts[MAX_CLIP_VERTS];
glpoly_t *p;
// calculate vertex values for sky box
for (p=fa->polys ; p ; p=p->next)
{
for (i=0 ; i<p->numverts ; i++)
{
VectorSubtract (p->verts[i], r_origin, verts[i]);
}
ClipSkyPolygon (p->numverts, verts[0], 0);
}
}
/*
==============
R_ClearSkyBox
==============
*/
void R_ClearSkyBox (void)
{
int i;
if (!cl.worldmodel) //allow skyboxes on non quake1 maps. (expect them even)
{
usingskybox = false;
return;
}
if (gl_skyboxname.modified)
R_LoadSkys();
if (!skyboxtex[0] || !skyboxtex[1] || !skyboxtex[2] || !skyboxtex[3] || !skyboxtex[4] || !skyboxtex[5])
{
usingskybox = false;
return;
}
usingskybox = true;
for (i=0 ; i<6 ; i++)
{
skymins[0][i] = skymins[1][i] = 9999;
skymaxs[0][i] = skymaxs[1][i] = -9999;
}
}
void MakeSkyVec (float s, float t, int axis)
{
vec3_t v, b;
int j, k;
b[0] = s*2300;
b[1] = t*2300;
b[2] = 2300;
for (j=0 ; j<3 ; j++)
{
k = st_to_vec[axis][j];
if (k < 0)
v[j] = -b[-k - 1];
else
v[j] = b[k - 1];
v[j] += r_origin[j];
}
// avoid bilerp seam
s = (s+1)*0.5;
t = (t+1)*0.5;
if (s < 1.0/512)
s = 1.0/512;
else if (s > 511.0/512)
s = 511.0/512;
if (t < 1.0/512)
t = 1.0/512;
else if (t > 511.0/512)
t = 511.0/512;
t = 1.0 - t;
glTexCoord2f (s, t);
glVertex3fv (v);
}
/*
==============
R_DrawSkyBox
==============
*/
int skytexorder[6] = {0,2,1,3,4,5};
void R_DrawSkyBox (msurface_t *s)
{
msurface_t *fa;
glpoly_t *poly;
int i;
if (!usingskybox)
return;
#if 0
glEnable (GL_BLEND);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glColor4f (1,1,1,0.5);
glDisable (GL_DEPTH_TEST);
#endif
for (i=0 ; i<6 ; i++)
{
if (skymins[0][i] >= skymaxs[0][i]
|| skymins[1][i] >= skymaxs[1][i])
continue;
GL_Bind (skyboxtex[skytexorder[i]]);
#if 0
skymins[0][i] = -1;
skymins[1][i] = -1;
skymaxs[0][i] = 1;
skymaxs[1][i] = 1;
#endif
glBegin (GL_QUADS);
MakeSkyVec (skymins[0][i], skymins[1][i], i);
MakeSkyVec (skymins[0][i], skymaxs[1][i], i);
MakeSkyVec (skymaxs[0][i], skymaxs[1][i], i);
MakeSkyVec (skymaxs[0][i], skymins[1][i], i);
glEnd ();
}
#if 0
glDisable (GL_BLEND);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glColor4f (1,1,1,0.5);
glEnable (GL_DEPTH_TEST);
#endif
if (!cls.allow_skyboxes && s) //allow a little extra fps.
{
glColorMask(0, 0, 0, 0); //depth only.
for (fa = s; fa; fa = fa->texturechain)
{
for (poly = fa->polys; poly; poly = poly->next)
{
glBegin (GL_POLYGON);
for (i = 0; i < poly->numverts; i++)
glVertex3fv (&poly->verts[0][0]+i*VERTEXSIZE);
glEnd ();
}
}
glColorMask(1, 1, 1, 1);
}
}
//===============================================================
/*
=============
R_InitSky
A sky texture is 256*128, with the right side being a masked overlay
==============
*/
void GLR_InitSky (texture_t *mt)
{
int i, j, p;
qbyte *src;
unsigned trans[128*128];
unsigned transpix;
int r, g, b;
unsigned *rgba;
char name[MAX_QPATH];
src = (qbyte *)mt + mt->offsets[0];
// make an average value for the back to avoid
// a fringe on the top level
r = g = b = 0;
for (i=0 ; i<128 ; i++)
for (j=0 ; j<128 ; j++)
{
p = src[i*256 + j + 128];
rgba = &d_8to24rgbtable[p];
trans[(i*128) + j] = *rgba;
r += ((qbyte *)rgba)[0];
g += ((qbyte *)rgba)[1];
b += ((qbyte *)rgba)[2];
}
((qbyte *)&transpix)[0] = r/(128*128);
((qbyte *)&transpix)[1] = g/(128*128);
((qbyte *)&transpix)[2] = b/(128*128);
((qbyte *)&transpix)[3] = 0;
sprintf(name, "%s_solid", mt->name);
strlwr(name);
solidskytexture = Mod_LoadReplacementTexture(name, true, false);
if (!solidskytexture)
solidskytexture = GL_LoadTexture32(name, 128, 128, trans, true, false);
/*
if (!solidskytexture)
solidskytexture = texture_extension_number++;
GL_Bind (solidskytexture );
glTexImage2D (GL_TEXTURE_2D, 0, gl_solid_format, 128, 128, 0, GL_RGBA, GL_UNSIGNED_BYTE, trans);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
*/
for (i=0 ; i<128 ; i++)
for (j=0 ; j<128 ; j++)
{
p = src[i*256 + j];
if (p == 0)
trans[(i*128) + j] = transpix;
else
trans[(i*128) + j] = d_8to24rgbtable[p];
}
sprintf(name, "%s_trans", mt->name);
strlwr(name);
alphaskytexture = Mod_LoadReplacementTexture(name, true, true);
if (!alphaskytexture)
alphaskytexture = GL_LoadTexture32(name, 128, 128, trans, true, true);
/*
if (!alphaskytexture)
alphaskytexture = texture_extension_number++;
GL_Bind(alphaskytexture);
glTexImage2D (GL_TEXTURE_2D, 0, gl_alpha_format, 128, 128, 0, GL_RGBA, GL_UNSIGNED_BYTE, trans);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
*/
}
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