java做的一个三维引擎

//made by Hu Pan 2004.9.8 import java.awt.*; import java.awt.event.*; import java.applet.*; public class polygonModeling extends Applet implements KeyListener, ActionListener{ private Image offScreenImage; private Ticker t; private paste[] Paste; private model[] models; private int numOfVisiblePolygons; private vector cameraPosition; // the change of camera position with respect of (0,0,0); private vector viewDirection; // the view direction of the camera private boolean seeThrough; private double xzRotate, yzRotate; private boolean UP_TYPED, DOWN_TYPED, RIGHT_TYPED, LEFT_TYPED, MOVE_FOWARD, MOVE_BACKWORD, SLIDE_LEFT, SLIDE_RIGHT; private double forward, backward, slideLeft, slideRight; int time; public void init(){ Paste = new paste[10000000]; models = new model[6]; models[0] = new desk(new vector(-18,-18,45)); models[1] = new book(new vector(-7,-1.97,46.1)); models[2] = new lamp(new vector(2,-1.97,56)); models[3] = new chair(new vector(-10,-20,32)); models[4] = new pencil(new vector(0,-1.9, 46)); models[5] = new floor(new vector(-28,-17.9,25)); //back ground cameraPosition = new vector(0,0,0); viewDirection = new vector(0,0,1); addKeyListener(this); requestFocus(); t = new Ticker(35); t.addActionListener(this); t.start(); } public void actionPerformed(ActionEvent e){ //============================control============================================= if(MOVE_FOWARD){ if(forward < 0.5) forward += 0.05; cameraPosition = cameraPosition.subtract(viewDirection.unit().scale(forward)); } else forward = 0; if(MOVE_BACKWORD){ if(backward < 0.5) backward += 0.05; cameraPosition = cameraPosition.add(viewDirection.unit().scale(backward)); } else backward = 0; if(SLIDE_LEFT){ if(slideLeft<0.5) slideLeft += 0.05; vector left = viewDirection.cross(new vector(-viewDirection.x, -1000000, -viewDirection.z)); cameraPosition = cameraPosition.add(left.unit().scale(slideLeft)); } else slideLeft = 0; if(SLIDE_RIGHT){ if(slideRight<0.5) slideRight += 0.05; vector right = viewDirection.cross(new vector(viewDirection.x, 1000000, viewDirection.z)); cameraPosition = cameraPosition.add(right.unit().scale(slideRight)); } else slideRight = 0; if(UP_TYPED){ if(yzRotate < Math.PI/2){ yzRotate+=0.03; if(yzRotate > Math.PI/2) yzRotate = Math.PI/2 - 0.001; } } if(DOWN_TYPED){ if(yzRotate > -Math.PI/2){ yzRotate-=0.03; if(yzRotate < -Math.PI/2) yzRotate = -Math.PI/2 + 0.001; } } if(LEFT_TYPED){ viewDirection = viewDirection.rotate_XZ(0.03); xzRotate-=0.03; } if(RIGHT_TYPED){ xzRotate+=0.03; viewDirection = viewDirection.rotate_XZ(-0.03); } viewDirection = viewDirection.rotate_vertical(yzRotate); //=================================end control============================================ //update the models' vertics accordiong to the user's move (camera's orientation) for(int i = 0; i < models.length; i++) models[i].update(cameraPosition, xzRotate, yzRotate); //sort models so that they are drawn in the right order sortModels(); //load polygons of the models numOfVisiblePolygons = 0; for(int i = 0; i < models.length-1; i++){ int start = numOfVisiblePolygons; for(int j = 0; j < models[i].getPolygon().length; j++){ if(models[i].getPolygon()[j].visible){ Paste[numOfVisiblePolygons] = models[i].getPolygon()[j]; numOfVisiblePolygons++; } } //sort polygons of the model so that they are drawn in the right order; sortPolygon(start, numOfVisiblePolygons); } repaint(); } //sort models private void sortModels(){ for(int i = 1; i < models.length-1; i++){ for(int j = 0; j <models.length - i-1; j++){ if(compare1(models[j], models[j+1])){ model temp = models[j+1]; models[j+1] = models[j]; models[j] = temp; } } } } //sort polygons private boolean compare1(model a, model b){ paste[] aPaste = a.getBoundary(); paste[] bPaste = b.getBoundary(); vector difference = a.getCentre().subtract(b.getCentre()); boolean insideA = true; boolean insideB = true; vector origin = new vector(0,0,0); for(int i = 0; i < 6; i++){ if(origin.subtract(aPaste[i].centre).dot(aPaste[i].normal) > 0) insideA = false; } for(int i = 0; i < 6; i++){ if(origin.subtract(bPaste[i].centre).dot(bPaste[i].normal) > 0) insideB = false; } if(insideA) return true; if(insideB) return false; boolean bCantBeSeen = true; for(int i = 0; i < 6; i++){ if(bPaste[i].visible){ bCantBeSeen = false; break; } } if(bCantBeSeen) return true; paste comparebleA = aPaste[0]; for(int i = 0; i < 6; i++){ if(aPaste[i].visible){ comparebleA = aPaste[i]; break; } } for(int i = 0; i < 6; i++){ if(aPaste[i].visible){ if(Math.abs(comparebleA.normal.dot(difference)) < Math.abs(aPaste[i].normal.dot(difference))) comparebleA = aPaste[i]; } } paste comparebleB = bPaste[0]; for(int i = 0; i < 6; i++){ if(bPaste[i].visible){ comparebleB = bPaste[i]; break; } } for(int i = 0; i < 6; i++){ if(bPaste[i].visible){ if(Math.abs(comparebleB.normal.dot(difference)) < Math.abs(bPaste[i].normal.dot(difference))) comparebleB = bPaste[i]; } } try{ if(compare2(comparebleA, comparebleB)) return true; }catch(Exception e){} return false; } //sort polygon private void sortPolygon(int start, int finish){ for(int i = start + 1; i < finish; i++){ for(int j = start; j <finish - 1; j++){ if(compare2(Paste[j], Paste[j+1])){ paste temp = Paste[j+1]; Paste[j+1] = Paste[j]; Paste[j] = temp; } } } } //check if polygon a is completely inside the plane spand by polygon b (use painter's method) public boolean compare2(paste a, paste b){ if(a.zMax < b.zMin) return true; if(a.zMin > b.zMax) return false; if(a.points[0].z < b.points[0].z && a.points[1].z < b.points[1].z && a.points[2].z < b.points[2].z && a.points[3].z < b.points[3].z) return true; boolean inside = true; for(int i = 0; i < b.points.length; i++){ if(b.points[i].subtract(a.centre).unit().dot(a.normal) > 0.0001 ){ inside = false; break; } } if(inside) return true; inside = true; for(int i = 0; i <a.points.length; i++){ if(a.points[i].subtract(b.centre).unit().dot(b.normal) < -0.0001 ){ inside = false; break; } } if(inside) return true; return false; } public void paint(Graphics g){ // draw back ground polygons first which always need to be draw at first for(int i = 0; i < models[models.length-1].getPolygon().length; i++){ if(models[models.length-1].getPolygon()[i].visible){ if(!seeThrough) models[models.length-1].getPolygon()[i].draw(g); } } //then draw the polygon that are sorted for(int i = 0; i < numOfVisiblePolygons; i++){ try{ if(Paste[i].innerPaste != null){ for(int j = 0; j < Paste[i].innerPaste.length; j++){ Paste[i].innerPaste[j].wireFrameOn = seeThrough; Paste[i].innerPaste[j].draw(g); } } else{ Paste[i].wireFrameOn = seeThrough; Paste[i].draw(g); } }catch(Exception e){} } } public void keyPressed(KeyEvent e){ if(e.getKeyCode() == KeyEvent.VK_UP) UP_TYPED = true; else if(e.getKeyCode() == KeyEvent.VK_DOWN) DOWN_TYPED = true; else if(e.getKeyCode() == KeyEvent.VK_LEFT) LEFT_TYPED = true; else if(e.getKeyCode() == KeyEvent.VK_RIGHT) RIGHT_TYPED = true; else if(e.getKeyChar() == 'w') MOVE_FOWARD = true; else if(e.getKe