/// <summary>
/// Calculate the polygon normals. By convention, LW's polygon normals
/// are found as the cross product of the first and last edges. It's
/// undefined for one- and two-point polygons.
/// </summary>
/// <param name="lwPolygonList"></param>
public void GetPolyNormals(ref lwPolygonList polygon)
{
float[] p1 = new float[3];
float[] p2 = new float[3];
float[] pn = new float[3];
float[] v1 = new float[3];
float[] v2 = new float[3];
for (int i = 0; i < polygon.count; i++)
{
if (polygon.pol[i].nverts < 3)
{
continue;
}
for (int j = 0; j < 3; j++)
{
p1[j] = pt[polygon.pol[i].v[0].index].pos[j];
p2[j] = pt[polygon.pol[i].v[1].index].pos[j];
pn[j] = pt[polygon.pol[i].v[polygon.pol[i].nverts - 1].index].pos[j];
}
for (int j = 0; j < 3; j++)
{
v1[j] = p2[j] - p1[j];
v2[j] = pn[j] - p1[j];
}
LwVecMath.cross(v1, v2, polygon.pol[i].norm);
LwVecMath.normalize(polygon.pol[i].norm);
}
}
/// <summary>
/// Calculate the vertex normals. For each polygon vertex, sum the
/// normals of the polygons that share the point. If the normals of the
/// current and adjacent polygons form an angle greater than the max
/// smoothing angle for the current polygon's surface, the normal of the
/// adjacent polygon is excluded from the sum. It's also excluded if the
/// polygons aren't in the same smoothing group.
///
/// Assumes that lwGetPointPolygons(), lwGetPolyNormals() and
/// lwResolvePolySurfaces() have already been called.
/// </summary>
/// <param name="lwPolygonList"></param>
public void GetVertNormals(ref lwPolygonList polygon)
{
int h, p;
float a;
for (int j = 0; j < polygon.count; j++)
{
for (int n = 0; n < polygon.pol[j].nverts; n++)
{
for (int k = 0; k < 3; k++)
{
polygon.pol[j].v[n].norm[k] = polygon.pol[j].norm[k];
}
if (polygon.pol[j].surf.smooth <= 0)
{
continue;
}
p = polygon.pol[j].v[n].index;
for (int g = 0; g < pt[p].npols; g++)
{
h = pt[p].pol[g];
if (h == j)
{
continue;
}
if (polygon.pol[j].smoothgrp != polygon.pol[h].smoothgrp)
{
continue;
}
a = LwVecMath.vecangle(polygon.pol[j].norm, polygon.pol[h].norm);
if (a > polygon.pol[j].surf.smooth)
{
continue;
}
for (int k = 0; k < 3; k++)
{
polygon.pol[j].v[n].norm[k] += polygon.pol[h].norm[k];
}
}
LwVecMath.normalize(polygon.pol[j].v[n].norm);
}
}
}
/// <summary>
/// For each point, fill in the indexes of the polygons that share the
/// point. Returns false if any of the memory allocations fail, otherwise
/// returns true.
/// </summary>
/// <param name="lwPolygonList"></param>
/// <returns></returns>
public bool GetPointPolygons(ref lwPolygonList polygon)
{
int k;
/* count the number of polygons per point */
for (int i = 0; i < polygon.count; i++)
{
for (int j = 0; j < polygon.pol[i].nverts; j++)
{
++pt[polygon.pol[i].v[j].index].npols;
}
}
/* alloc per-point polygon arrays */
for (int i = 0; i < count; i++)
{
if (pt[i].npols == 0)
{
continue;
}
pt[i].pol = new int[pt[i].npols];
if (pt[i].pol == null)
{
return(false);
}
pt[i].npols = 0;
}
/* fill in polygon array for each point */
for (int i = 0; i < polygon.count; i++)
{
for (int j = 0; j < polygon.pol[i].nverts; j++)
{
k = polygon.pol[i].v[j].index;
pt[k].pol[pt[k].npols] = i;
++pt[k].npols;
}
}
return(true);
}
/// <summary>
/// Calculate the polygon normals. By convention, LW's polygon normals
/// are found as the cross product of the first and last edges. It's
/// undefined for one- and two-point polygons.
/// </summary>
/// <param name="lwPolygonList"></param>
public void GetPolyNormals(ref lwPolygonList polygon)
{
float[] p1 = new float[3];
float[] p2 = new float[3];
float[] pn = new float[3];
float[] v1 = new float[3];
float[] v2 = new float[3];
for (int i = 0; i < polygon.count; i++)
{
if (polygon.pol[i].nverts < 3)
continue;
for (int j = 0; j < 3; j++)
{
p1[j] = pt[polygon.pol[i].v[0].index].pos[j];
p2[j] = pt[polygon.pol[i].v[1].index].pos[j];
pn[j] = pt[polygon.pol[i].v[polygon.pol[i].nverts - 1].index].pos[j];
}
for (int j = 0; j < 3; j++)
{
v1[j] = p2[j] - p1[j];
v2[j] = pn[j] - p1[j];
}
LwVecMath.cross(v1, v2, polygon.pol[i].norm);
LwVecMath.normalize(polygon.pol[i].norm);
}
}
/// <summary>
/// Calculate the vertex normals. For each polygon vertex, sum the
/// normals of the polygons that share the point. If the normals of the
/// current and adjacent polygons form an angle greater than the max
/// smoothing angle for the current polygon's surface, the normal of the
/// adjacent polygon is excluded from the sum. It's also excluded if the
/// polygons aren't in the same smoothing group.
///
/// Assumes that lwGetPointPolygons(), lwGetPolyNormals() and
/// lwResolvePolySurfaces() have already been called.
/// </summary>
/// <param name="lwPolygonList"></param>
public void GetVertNormals(ref lwPolygonList polygon)
{
int h, p;
float a;
for (int j = 0; j < polygon.count; j++)
{
for (int n = 0; n < polygon.pol[j].nverts; n++)
{
for (int k = 0; k < 3; k++)
polygon.pol[j].v[n].norm[k] = polygon.pol[j].norm[k];
if (polygon.pol[j].surf.smooth <= 0)
continue;
p = polygon.pol[j].v[n].index;
for (int g = 0; g < pt[p].npols; g++)
{
h = pt[p].pol[g];
if (h == j)
continue;
if (polygon.pol[j].smoothgrp != polygon.pol[h].smoothgrp)
continue;
a = LwVecMath.vecangle(polygon.pol[j].norm, polygon.pol[h].norm);
if (a > polygon.pol[j].surf.smooth)
continue;
for (int k = 0; k < 3; k++)
polygon.pol[j].v[n].norm[k] += polygon.pol[h].norm[k];
}
LwVecMath.normalize(polygon.pol[j].v[n].norm);
}
}
}
/// <summary>
/// For each point, fill in the indexes of the polygons that share the
/// point. Returns false if any of the memory allocations fail, otherwise
/// returns true.
/// </summary>
/// <param name="lwPolygonList"></param>
/// <returns></returns>
public bool GetPointPolygons(ref lwPolygonList polygon)
{
int k;
/* count the number of polygons per point */
for (int i = 0; i < polygon.count; i++)
for (int j = 0; j < polygon.pol[i].nverts; j++)
++pt[polygon.pol[i].v[j].index].npols;
/* alloc per-point polygon arrays */
for (int i = 0; i < count; i++)
{
if (pt[i].npols == 0)
continue;
pt[i].pol = new int[pt[i].npols];
if (pt[i].pol == null)
return false;
pt[i].npols = 0;
}
/* fill in polygon array for each point */
for (int i = 0; i < polygon.count; i++)
{
for (int j = 0; j < polygon.pol[i].nverts; j++)
{
k = polygon.pol[i].v[j].index;
pt[k].pol[pt[k].npols] = i;
++pt[k].npols;
}
}
return true;
}
/// <summary>
/// Read polygon records from a POLS chunk in an LWO2 file. The polygons
/// are added to the array in the lwPolygonList.
/// </summary>
public bool GetPolygons(FileStream fp, int cksize, ref lwPolygonList plist, int ptoffset)
{
BinaryReader read = new BinaryReader(fp);
int pp;
lwPolVert pv;
byte[] buf;
int bp;
int j, flags, nv, nverts, npols;
uint type;
if (cksize == 0)
{
return(true);
}
/* read the whole chunk */
int flen = 0;
type = lwio.getU4(read, ref flen);
buf = lwio.getbytes(read, cksize - 4, ref flen);
if (cksize != flen)
{
goto Fail;
}
/* count the polygons and vertices */
nverts = 0;
npols = 0;
bp = 0;
while (bp < cksize - 4)
{
nv = lwio.sgetU2(buf, ref bp, ref flen);
nv &= 0x03FF;
nverts += nv;
npols++;
for (int i = 0; i < nv; i++)
{
;
}
j = lwio.sgetVX(buf, ref bp, ref flen);
}
AllocPolygons(npols, nverts);
/* fill in the new polygons */
bp = 0;
pp = plist.offset;
pv = plist.pol[0].v[plist.voffset];
for (int i = 0; i < npols; i++)
{
nv = lwio.sgetU2(buf, ref bp, ref flen);
flags = nv & 0xFC00;
nv &= 0x03FF;
plist.pol[pp].nverts = nv;
plist.pol[pp].flags = flags;
plist.pol[pp].type = type;
//if (plist.pol[pp].v == null)
// plist.pol[pp].v = pv;
//for (int j = 0; j < nv; j++)
// plist.pol[pp].v[j].index = lwio.sgetVX(buf, ref bp, ref flen) + ptoffset;
pp++;
//pv += nv;
}
return(true);
Fail:
return(false);
}
/// <summary>
/// Read polygon records from a POLS chunk in an LWO2 file. The polygons
/// are added to the array in the lwPolygonList.
/// </summary>
public bool GetPolygons(FileStream fp, int cksize, ref lwPolygonList plist, int ptoffset)
{
BinaryReader read = new BinaryReader(fp);
int pp;
lwPolVert pv;
byte[] buf;
int bp;
int j, flags, nv, nverts, npols;
uint type;
if (cksize == 0)
return true;
/* read the whole chunk */
int flen = 0;
type = lwio.getU4(read, ref flen);
buf = lwio.getbytes(read, cksize - 4, ref flen);
if (cksize != flen)
goto Fail;
/* count the polygons and vertices */
nverts = 0;
npols = 0;
bp = 0;
while (bp < cksize - 4)
{
nv = lwio.sgetU2(buf, ref bp, ref flen);
nv &= 0x03FF;
nverts += nv;
npols++;
for (int i = 0; i < nv; i++) ;
j = lwio.sgetVX(buf, ref bp, ref flen);
}
AllocPolygons(npols, nverts);
/* fill in the new polygons */
bp = 0;
pp = plist.offset;
pv = plist.pol[0].v[plist.voffset];
for (int i = 0; i < npols; i++)
{
nv = lwio.sgetU2(buf, ref bp, ref flen);
flags = nv & 0xFC00;
nv &= 0x03FF;
plist.pol[pp].nverts = nv;
plist.pol[pp].flags = flags;
plist.pol[pp].type = type;
//if (plist.pol[pp].v == null)
// plist.pol[pp].v = pv;
//for (int j = 0; j < nv; j++)
// plist.pol[pp].v[j].index = lwio.sgetVX(buf, ref bp, ref flen) + ptoffset;
pp++;
//pv += nv;
}
return true;
Fail:
return false;
}
