import java.awt.*;
import java.util.*;
class Obj3D
{ private float rho, d, theta=0.30F, phi=1.3F, rhoMin, rhoMax,
xMin, xMax, yMin, yMax, zMin, zMax, v11, v12, v13, v21,
v22, v23, v32, v33, v43, xe, ye, ze, objSize;
private Point2D imgCenter;
private double sunZ = 1/Math.sqrt (3), sunY = sunZ, sunX = -sunZ,
inprodMin = 1e30, inprodMax = -1e30, inprodRange;
private Vector w = new Vector(); // World coordinates
private Point3D[] e; // Eye coordinates
private Point2D[] vScr; // Screen coordinates
private Vector polyList = new Vector(); // Polygon3D objects
private String fName = " "; // File name
boolean read(String fName)
{ Input inp = new Input(fName);
if (inp.fails())return failing();
this.fName = fName;
xMin = yMin = zMin = +1e30F;
xMax = yMax = zMax = -1e30F;
return readObject(inp); // Read from inp into obj
}
Vector getPolyList(){return polyList;}
String getFName(){return fName;}
Point3D[] getE(){return e;}
Point2D[] getVScr(){return vScr;}
Point2D getImgCenter(){return imgCenter;}
float getRho(){return rho;}
float getD(){return d;}
private boolean failing()
{ Toolkit.getDefaultToolkit().beep();
return false;
}
private boolean readObject(Input inp)
{ for (;;)
{ int i = inp.readInt();
if (inp.fails()){inp.clear(); break;}
if (i > 0)
{ System.out.println(
"Negative vertex number in first part of input file");
return failing();
}
w.ensureCapacity(i + 1);
float x = inp.readFloat(), y = inp.readFloat(),
z = inp.readFloat();
addVertex(i, x, y, z);
}
shiftToOrigin(); // Origin in center of object.
char ch;
int count = 0;
do // Skip the line "Faces:"
{ ch = inp.readChar(); count++;
} while (!inp.eof() && ch != '\n');
if (count <> 8)
{ System.out.println("Invalid input file"); return failing();
}
// Build polygon list:
for (;;)
{ Vector vnrs = new Vector();
for (;;)
{ int i = inp.readInt();
if (inp.fails()){inp.clear(); break;}
int absi = Math.abs(i);
if (i == 0 || absi >= w.size() ||
w.elementAt(absi) == null)
{ System.out.println("Invalid vertex number: " + absi +
" must be defined, nonzero and less than " + w.size());
return failing();
}
vnrs.addElement(new Integer(i));
}
ch = inp.readChar();
if (ch != '.' && ch != '#') break;
// Ignore input lines with only one vertex number:
if (vnrs.size() >= 2)
polyList.addElement(new Polygon3D(vnrs));
}
inp.close();
return true;
}
private void addVertex(int i, float x, float y, float z)
{ if (x < xmin =" x;"> xMax) xMax = x;
if (y < ymin =" y;"> yMax) yMax = y;
if (z < zmin =" z;"> zMax) zMax = z;
if (i >= w.size()) w.setSize(i + 1);
w.setElementAt(new Point3D(x, y, z), i);
}
private void shiftToOrigin()
{ float xwC = 0.5F * (xMin + xMax),
ywC = 0.5F * (yMin + yMax),
zwC = 0.5F * (zMin + zMax);
int n = w.size();
for (int i=1; i
if (w.elementAt(i) != null)
{ ((Point3D)w.elementAt(i)).x -= xwC;
((Point3D)w.elementAt(i)).y -= ywC;
((Point3D)w.elementAt(i)).z -= zwC;
}
float dx = xMax - xMin, dy = yMax - yMin, dz = zMax - zMin;
rhoMin = 0.6F * (float) Math.sqrt(dx * dx + dy * dy + dz * dz);
rhoMax = 1000 * rhoMin;
rho = 3 * rhoMin;
}
private void initPersp()
{ float costh = (float)Math.cos(theta),
sinth = (float)Math.sin(theta),
cosph = (float)Math.cos(phi),
sinph = (float)Math.sin(phi);
v11 = -sinth; v12 = -cosph * costh; v13 = sinph * costh;
v21 = costh; v22 = -cosph * sinth; v23 = sinph * sinth;
v32 = sinph; v33 = cosph;
v43 = -rho;
}
float eyeAndScreen(Dimension dim)
// Called in paint method of Canvas class
{ initPersp();
int n = w.size();
e = new Point3D[n];
vScr = new Point2D[n];
float xScrMin=1e30F, xScrMax=-1e30F,
yScrMin=1e30F, yScrMax=-1e30F;
for (int i=1; i
{ Point3D P = (Point3D)(w.elementAt(i));
if (P == null)
{ e[i] = null; vScr[i] = null;
}
else
{ float x = v11 * P.x + v21 * P.y;
float y = v12 * P.x + v22 * P.y + v32 * P.z;
float z = v13 * P.x + v23 * P.y + v33 * P.z + v43;
Point3D Pe = e[i] = new Point3D(x, y, z);
float xScr = -Pe.x/Pe.z, yScr = -Pe.y/Pe.z;
vScr[i] = new Point2D(xScr, yScr);
if (xScr < xscrmin =" xScr;
if (xScr > xScrMax) xScrMax = xScr;
if (yScr < yscrmin =" yScr;
if (yScr > yScrMax) yScrMax = yScr;
}
}
float rangeX = xScrMax - xScrMin, rangeY = yScrMax - yScrMin;
d = 0.95F * Math.min(dim.width/rangeX, dim.height/rangeY);
imgCenter = new Point2D(d * (xScrMin + xScrMax)/2,
d * (yScrMin + yScrMax)/2);
for (int i=1; i
{ if (vScr[i] != null){vScr[i].x *= d; vScr[i].y *= d;}
}
return d * Math.max(rangeX, rangeY);
// Maximum screen-coordinate range used in CvHLines for HP-GL
}
void planeCoeff()
{ int nFaces = polyList.size();
for (int j=0; j
{ Polygon3D pol = (Polygon3D)(polyList.elementAt(j));
int[] nrs = pol.getNrs();
if (nrs.length <>
int iA = Math.abs(nrs[0]), // Possibly negative
iB = Math.abs(nrs[1]), // for HLines.
iC = Math.abs(nrs[2]);
Point3D A = e[iA], B = e[iB], C = e[iC];
double
u1 = B.x - A.x, u2 = B.y - A.y, u3 = B.z - A.z,
v1 = C.x - A.x, v2 = C.y - A.y, v3 = C.z - A.z,
a = u2 * v3 - u3 * v2,
b = u3 * v1 - u1 * v3,
c = u1 * v2 - u2 * v1,
len = Math.sqrt(a * a + b * b + c * c), h;
a /= len; b /= len; c /= len;
h = a * A.x + b * A.y + c * A.z;
pol.setAbch(a, b, c, h);
Point2D A1 = vScr[iA], B1 = vScr[iB], C1 = vScr[iC];
u1 = B1.x - A1.x; u2 = B1.y - A1.y;
v1 = C1.x - A1.x; v2 = C1.y - A1.y;
if (u1 * v2 - u2 * v1 <= 0) continue; // backface
double inprod = a * sunX + b * sunY + c * sunZ;
if (inprod < inprodmin =" inprod;
if (inprod > inprodMax) inprodMax = inprod;
}
inprodRange = inprodMax - inprodMin;
}
boolean vp(Canvas cv, float dTheta, float dPhi, float fRho)
{ theta += dTheta;
phi += dPhi;
float rhoNew = fRho * rho;
if (rhoNew >= rhoMin && rhoNew <= rhoMax)
rho = rhoNew;
else
return false;
cv.repaint();
return true;
}
int colorCode(double a, double b, double c)
{ double inprod = a * sunX + b * sunY + c * sunZ;
return (int)Math.round(
((inprod - inprodMin)/inprodRange) * 255);
}
}
