void MpSurfacePrism (Scene &S, const Matrix &Z, int nsegments,
double wx, double wy,
const ColorMap &cmap,double cmin, double cmax)
{
// nothing that can be drawn
if ( Z.Empty() ) return;
// 4-segments faster special case
if (nsegments == 4) {
MpSurfacePrism4(S,Z,wx,wy,cmap,cmin,cmax);
return;
}
// find the extrema
double zmin = Min(Z);
// check for valid nsegments values
MpForceRange(nsegments, 3, MaxVertices);
// check if a colormap should be used
double dz,cscale = 0;
bool usecolormap;
int ncmap = cmap.Size()-1;
if (cmap) {
usecolormap = true;
dz = cmax - cmin;
cscale = (dz == 0.0) ? 0 : ncmap/dz;
} else
usecolormap = false;
// add prism
for (int x = Z.Rlo(); x <= Z.Rhi(); x++)
for (int y = Z.Clo(); y <= Z.Chi(); y++) {
double z = Z(x,y),
height = 0.5 * (z - zmin);
Trafo T = trans(y,height+zmin,x)
* scale(wy,height,wx)
* rot(Trafo::XAxis,M_PI/2);
// coloring
const ColorB *color;
if (usecolormap) {
int c = int((z-cmin)*cscale);
if (c > ncmap)
c = ncmap;
else if (c < 0)
c = 0;
color = &cmap[c];
} else
color = (ColorB*)NULL;
cylinder(S,nsegments,T,color);
}
}
static void MpSurfacePrism4 (Scene &S, const Matrix &Z,
double wx, double wy,
const ColorMap &cmap, double cmin, double cmax)
{
// nothing that can be drawn
if ( Z.Empty() ) return;
// find the minimum
double zmin = Min(Z);
// check if a colormap should be used
double dz,cscale = 0;
bool usecolormap;
int ncmap = cmap.Size()-1;
if (cmap) {
usecolormap = true;
dz = cmax - cmin;
cscale = (dz == 0.0) ? 0.0 : ncmap/dz;
} else
usecolormap = false;
// add square prisms
for (int x = Z.Rlo(); x <= Z.Rhi(); x++)
for (int y = Z.Clo(); y <= Z.Chi(); y++) {
double z = Z(x,y),
height = 0.5 * (z - zmin);
Trafo T = trans(y,height+zmin,x)
* scale(wy,height,wx);
// coloring
const ColorB *color;
if (usecolormap) {
int c = int((z-cmin)*cscale);
if (c > ncmap)
c = ncmap;
else if (c < 0)
c = 0;
color = &cmap[c];
} else
color = (ColorB*)NULL;
MpCube(S,T,color);
}
}