mirror of
https://github.com/DrBeef/QuakeQuest.git
synced 2024-12-22 10:31:24 +00:00
310 lines
11 KiB
C
310 lines
11 KiB
C
|
|
/*
|
|
Polygon clipping routines written by Forest Hale and placed into public domain.
|
|
*/
|
|
|
|
#include <math.h>
|
|
#include "polygon.h"
|
|
|
|
void PolygonF_QuadForPlane(float *outpoints, float planenormalx, float planenormaly, float planenormalz, float planedist, float quadsize)
|
|
{
|
|
float d, quadright[3], quadup[3];
|
|
if (fabs(planenormalz) > fabs(planenormalx) && fabs(planenormalz) > fabs(planenormaly))
|
|
{
|
|
quadup[0] = 1;
|
|
quadup[1] = 0;
|
|
quadup[2] = 0;
|
|
}
|
|
else
|
|
{
|
|
quadup[0] = 0;
|
|
quadup[1] = 0;
|
|
quadup[2] = 1;
|
|
}
|
|
// d = -DotProduct(quadup, planenormal);
|
|
d = -(quadup[0] * planenormalx + quadup[1] * planenormaly + quadup[2] * planenormalz);
|
|
// VectorMA(quadup, d, planenormal, quadup);
|
|
quadup[0] += d * planenormalx;
|
|
quadup[1] += d * planenormaly;
|
|
quadup[2] += d * planenormalz;
|
|
// VectorNormalize(quadup);
|
|
d = (float)(1.0 / sqrt(quadup[0] * quadup[0] + quadup[1] * quadup[1] + quadup[2] * quadup[2]));
|
|
quadup[0] *= d;
|
|
quadup[1] *= d;
|
|
quadup[2] *= d;
|
|
// CrossProduct(quadup,planenormal,quadright);
|
|
quadright[0] = quadup[1] * planenormalz - quadup[2] * planenormaly;
|
|
quadright[1] = quadup[2] * planenormalx - quadup[0] * planenormalz;
|
|
quadright[2] = quadup[0] * planenormaly - quadup[1] * planenormalx;
|
|
// make the points
|
|
outpoints[0] = planedist * planenormalx - quadsize * quadright[0] + quadsize * quadup[0];
|
|
outpoints[1] = planedist * planenormaly - quadsize * quadright[1] + quadsize * quadup[1];
|
|
outpoints[2] = planedist * planenormalz - quadsize * quadright[2] + quadsize * quadup[2];
|
|
outpoints[3] = planedist * planenormalx + quadsize * quadright[0] + quadsize * quadup[0];
|
|
outpoints[4] = planedist * planenormaly + quadsize * quadright[1] + quadsize * quadup[1];
|
|
outpoints[5] = planedist * planenormalz + quadsize * quadright[2] + quadsize * quadup[2];
|
|
outpoints[6] = planedist * planenormalx + quadsize * quadright[0] - quadsize * quadup[0];
|
|
outpoints[7] = planedist * planenormaly + quadsize * quadright[1] - quadsize * quadup[1];
|
|
outpoints[8] = planedist * planenormalz + quadsize * quadright[2] - quadsize * quadup[2];
|
|
outpoints[9] = planedist * planenormalx - quadsize * quadright[0] - quadsize * quadup[0];
|
|
outpoints[10] = planedist * planenormaly - quadsize * quadright[1] - quadsize * quadup[1];
|
|
outpoints[11] = planedist * planenormalz - quadsize * quadright[2] - quadsize * quadup[2];
|
|
}
|
|
|
|
void PolygonD_QuadForPlane(double *outpoints, double planenormalx, double planenormaly, double planenormalz, double planedist, double quadsize)
|
|
{
|
|
double d, quadright[3], quadup[3];
|
|
if (fabs(planenormalz) > fabs(planenormalx) && fabs(planenormalz) > fabs(planenormaly))
|
|
{
|
|
quadup[0] = 1;
|
|
quadup[1] = 0;
|
|
quadup[2] = 0;
|
|
}
|
|
else
|
|
{
|
|
quadup[0] = 0;
|
|
quadup[1] = 0;
|
|
quadup[2] = 1;
|
|
}
|
|
// d = -DotProduct(quadup, planenormal);
|
|
d = -(quadup[0] * planenormalx + quadup[1] * planenormaly + quadup[2] * planenormalz);
|
|
// VectorMA(quadup, d, planenormal, quadup);
|
|
quadup[0] += d * planenormalx;
|
|
quadup[1] += d * planenormaly;
|
|
quadup[2] += d * planenormalz;
|
|
// VectorNormalize(quadup);
|
|
d = 1.0 / sqrt(quadup[0] * quadup[0] + quadup[1] * quadup[1] + quadup[2] * quadup[2]);
|
|
quadup[0] *= d;
|
|
quadup[1] *= d;
|
|
quadup[2] *= d;
|
|
// CrossProduct(quadup,planenormal,quadright);
|
|
quadright[0] = quadup[1] * planenormalz - quadup[2] * planenormaly;
|
|
quadright[1] = quadup[2] * planenormalx - quadup[0] * planenormalz;
|
|
quadright[2] = quadup[0] * planenormaly - quadup[1] * planenormalx;
|
|
// make the points
|
|
outpoints[0] = planedist * planenormalx - quadsize * quadright[0] + quadsize * quadup[0];
|
|
outpoints[1] = planedist * planenormaly - quadsize * quadright[1] + quadsize * quadup[1];
|
|
outpoints[2] = planedist * planenormalz - quadsize * quadright[2] + quadsize * quadup[2];
|
|
outpoints[3] = planedist * planenormalx + quadsize * quadright[0] + quadsize * quadup[0];
|
|
outpoints[4] = planedist * planenormaly + quadsize * quadright[1] + quadsize * quadup[1];
|
|
outpoints[5] = planedist * planenormalz + quadsize * quadright[2] + quadsize * quadup[2];
|
|
outpoints[6] = planedist * planenormalx + quadsize * quadright[0] - quadsize * quadup[0];
|
|
outpoints[7] = planedist * planenormaly + quadsize * quadright[1] - quadsize * quadup[1];
|
|
outpoints[8] = planedist * planenormalz + quadsize * quadright[2] - quadsize * quadup[2];
|
|
outpoints[9] = planedist * planenormalx - quadsize * quadright[0] - quadsize * quadup[0];
|
|
outpoints[10] = planedist * planenormaly - quadsize * quadright[1] - quadsize * quadup[1];
|
|
outpoints[11] = planedist * planenormalz - quadsize * quadright[2] - quadsize * quadup[2];
|
|
}
|
|
|
|
int PolygonF_Clip(int innumpoints, const float *inpoints, float planenormalx, float planenormaly, float planenormalz, float planedist, float epsilon, int outfrontmaxpoints, float *outfrontpoints)
|
|
{
|
|
int i, frontcount = 0;
|
|
const float *n, *p;
|
|
float frac, pdist, ndist;
|
|
if (innumpoints < 1)
|
|
return 0;
|
|
n = inpoints;
|
|
ndist = n[0] * planenormalx + n[1] * planenormaly + n[2] * planenormalz - planedist;
|
|
for(i = 0;i < innumpoints;i++)
|
|
{
|
|
p = n;
|
|
pdist = ndist;
|
|
n = inpoints + ((i + 1) < innumpoints ? (i + 1) : 0) * 3;
|
|
ndist = n[0] * planenormalx + n[1] * planenormaly + n[2] * planenormalz - planedist;
|
|
if (pdist >= -epsilon)
|
|
{
|
|
if (frontcount < outfrontmaxpoints)
|
|
{
|
|
*outfrontpoints++ = p[0];
|
|
*outfrontpoints++ = p[1];
|
|
*outfrontpoints++ = p[2];
|
|
}
|
|
frontcount++;
|
|
}
|
|
if ((pdist > epsilon && ndist < -epsilon) || (pdist < -epsilon && ndist > epsilon))
|
|
{
|
|
frac = pdist / (pdist - ndist);
|
|
if (frontcount < outfrontmaxpoints)
|
|
{
|
|
*outfrontpoints++ = p[0] + frac * (n[0] - p[0]);
|
|
*outfrontpoints++ = p[1] + frac * (n[1] - p[1]);
|
|
*outfrontpoints++ = p[2] + frac * (n[2] - p[2]);
|
|
}
|
|
frontcount++;
|
|
}
|
|
}
|
|
return frontcount;
|
|
}
|
|
|
|
int PolygonD_Clip(int innumpoints, const double *inpoints, double planenormalx, double planenormaly, double planenormalz, double planedist, double epsilon, int outfrontmaxpoints, double *outfrontpoints)
|
|
{
|
|
int i, frontcount = 0;
|
|
const double *n, *p;
|
|
double frac, pdist, ndist;
|
|
if (innumpoints < 1)
|
|
return 0;
|
|
n = inpoints;
|
|
ndist = n[0] * planenormalx + n[1] * planenormaly + n[2] * planenormalz - planedist;
|
|
for(i = 0;i < innumpoints;i++)
|
|
{
|
|
p = n;
|
|
pdist = ndist;
|
|
n = inpoints + ((i + 1) < innumpoints ? (i + 1) : 0) * 3;
|
|
ndist = n[0] * planenormalx + n[1] * planenormaly + n[2] * planenormalz - planedist;
|
|
if (pdist >= -epsilon)
|
|
{
|
|
if (frontcount < outfrontmaxpoints)
|
|
{
|
|
*outfrontpoints++ = p[0];
|
|
*outfrontpoints++ = p[1];
|
|
*outfrontpoints++ = p[2];
|
|
}
|
|
frontcount++;
|
|
}
|
|
if ((pdist > epsilon && ndist < -epsilon) || (pdist < -epsilon && ndist > epsilon))
|
|
{
|
|
frac = pdist / (pdist - ndist);
|
|
if (frontcount < outfrontmaxpoints)
|
|
{
|
|
*outfrontpoints++ = p[0] + frac * (n[0] - p[0]);
|
|
*outfrontpoints++ = p[1] + frac * (n[1] - p[1]);
|
|
*outfrontpoints++ = p[2] + frac * (n[2] - p[2]);
|
|
}
|
|
frontcount++;
|
|
}
|
|
}
|
|
return frontcount;
|
|
}
|
|
|
|
void PolygonF_Divide(int innumpoints, const float *inpoints, float planenormalx, float planenormaly, float planenormalz, float planedist, float epsilon, int outfrontmaxpoints, float *outfrontpoints, int *neededfrontpoints, int outbackmaxpoints, float *outbackpoints, int *neededbackpoints, int *oncountpointer)
|
|
{
|
|
int i, frontcount = 0, backcount = 0, oncount = 0;
|
|
const float *n, *p;
|
|
float frac, pdist, ndist;
|
|
if (innumpoints)
|
|
{
|
|
n = inpoints;
|
|
ndist = n[0] * planenormalx + n[1] * planenormaly + n[2] * planenormalz - planedist;
|
|
for(i = 0;i < innumpoints;i++)
|
|
{
|
|
p = n;
|
|
pdist = ndist;
|
|
n = inpoints + ((i + 1) < innumpoints ? (i + 1) : 0) * 3;
|
|
ndist = n[0] * planenormalx + n[1] * planenormaly + n[2] * planenormalz - planedist;
|
|
if (pdist >= -epsilon)
|
|
{
|
|
if (pdist <= epsilon)
|
|
oncount++;
|
|
if (frontcount < outfrontmaxpoints)
|
|
{
|
|
*outfrontpoints++ = p[0];
|
|
*outfrontpoints++ = p[1];
|
|
*outfrontpoints++ = p[2];
|
|
}
|
|
frontcount++;
|
|
}
|
|
if (pdist <= epsilon)
|
|
{
|
|
if (backcount < outbackmaxpoints)
|
|
{
|
|
*outbackpoints++ = p[0];
|
|
*outbackpoints++ = p[1];
|
|
*outbackpoints++ = p[2];
|
|
}
|
|
backcount++;
|
|
}
|
|
if ((pdist > epsilon && ndist < -epsilon) || (pdist < -epsilon && ndist > epsilon))
|
|
{
|
|
oncount++;
|
|
frac = pdist / (pdist - ndist);
|
|
if (frontcount < outfrontmaxpoints)
|
|
{
|
|
*outfrontpoints++ = p[0] + frac * (n[0] - p[0]);
|
|
*outfrontpoints++ = p[1] + frac * (n[1] - p[1]);
|
|
*outfrontpoints++ = p[2] + frac * (n[2] - p[2]);
|
|
}
|
|
frontcount++;
|
|
if (backcount < outbackmaxpoints)
|
|
{
|
|
*outbackpoints++ = p[0] + frac * (n[0] - p[0]);
|
|
*outbackpoints++ = p[1] + frac * (n[1] - p[1]);
|
|
*outbackpoints++ = p[2] + frac * (n[2] - p[2]);
|
|
}
|
|
backcount++;
|
|
}
|
|
}
|
|
}
|
|
if (neededfrontpoints)
|
|
*neededfrontpoints = frontcount;
|
|
if (neededbackpoints)
|
|
*neededbackpoints = backcount;
|
|
if (oncountpointer)
|
|
*oncountpointer = oncount;
|
|
}
|
|
|
|
void PolygonD_Divide(int innumpoints, const double *inpoints, double planenormalx, double planenormaly, double planenormalz, double planedist, double epsilon, int outfrontmaxpoints, double *outfrontpoints, int *neededfrontpoints, int outbackmaxpoints, double *outbackpoints, int *neededbackpoints, int *oncountpointer)
|
|
{
|
|
int i = 0, frontcount = 0, backcount = 0, oncount = 0;
|
|
const double *n, *p;
|
|
double frac, pdist, ndist;
|
|
if (innumpoints)
|
|
{
|
|
n = inpoints;
|
|
ndist = n[0] * planenormalx + n[1] * planenormaly + n[2] * planenormalz - planedist;
|
|
for(i = 0;i < innumpoints;i++)
|
|
{
|
|
p = n;
|
|
pdist = ndist;
|
|
n = inpoints + ((i + 1) < innumpoints ? (i + 1) : 0) * 3;
|
|
ndist = n[0] * planenormalx + n[1] * planenormaly + n[2] * planenormalz - planedist;
|
|
if (pdist >= -epsilon)
|
|
{
|
|
if (pdist <= epsilon)
|
|
oncount++;
|
|
if (frontcount < outfrontmaxpoints)
|
|
{
|
|
*outfrontpoints++ = p[0];
|
|
*outfrontpoints++ = p[1];
|
|
*outfrontpoints++ = p[2];
|
|
}
|
|
frontcount++;
|
|
}
|
|
if (pdist <= epsilon)
|
|
{
|
|
if (backcount < outbackmaxpoints)
|
|
{
|
|
*outbackpoints++ = p[0];
|
|
*outbackpoints++ = p[1];
|
|
*outbackpoints++ = p[2];
|
|
}
|
|
backcount++;
|
|
}
|
|
if ((pdist > epsilon && ndist < -epsilon) || (pdist < -epsilon && ndist > epsilon))
|
|
{
|
|
oncount++;
|
|
frac = pdist / (pdist - ndist);
|
|
if (frontcount < outfrontmaxpoints)
|
|
{
|
|
*outfrontpoints++ = p[0] + frac * (n[0] - p[0]);
|
|
*outfrontpoints++ = p[1] + frac * (n[1] - p[1]);
|
|
*outfrontpoints++ = p[2] + frac * (n[2] - p[2]);
|
|
}
|
|
frontcount++;
|
|
if (backcount < outbackmaxpoints)
|
|
{
|
|
*outbackpoints++ = p[0] + frac * (n[0] - p[0]);
|
|
*outbackpoints++ = p[1] + frac * (n[1] - p[1]);
|
|
*outbackpoints++ = p[2] + frac * (n[2] - p[2]);
|
|
}
|
|
backcount++;
|
|
}
|
|
}
|
|
}
|
|
if (neededfrontpoints)
|
|
*neededfrontpoints = frontcount;
|
|
if (neededbackpoints)
|
|
*neededbackpoints = backcount;
|
|
if (oncountpointer)
|
|
*oncountpointer = oncount;
|
|
}
|
|
|