public void render(int offset, int left, int right) {
ShadedSurface texture = (ShadedSurface) currentTexture;
float u = SCALE * a.getDotProduct(viewPos);
float v = SCALE * b.getDotProduct(viewPos);
float z = c.getDotProduct(viewPos);
float du = INTERP_SIZE * SCALE * a.x;
float dv = INTERP_SIZE * SCALE * b.x;
float dz = INTERP_SIZE * c.x;
int nextTx = (int) (u / z);
int nextTy = (int) (v / z);
int depth = (int) (w * z);
int dDepth = (int) (w * c.x);
int x = left;
while (x <= right) {
int tx = nextTx;
int ty = nextTy;
int maxLength = right - x + 1;
if (maxLength > INTERP_SIZE) {
u += du;
v += dv;
z += dz;
nextTx = (int) (u / z);
nextTy = (int) (v / z);
int dtx = (nextTx - tx) >> INTERP_SIZE_BITS;
int dty = (nextTy - ty) >> INTERP_SIZE_BITS;
int endOffset = offset + INTERP_SIZE;
while (offset < endOffset) {
if (zBuffer.checkDepth(offset, (short) (depth >> SCALE_BITS))) {
doubleBufferData[offset] = texture.getColor(tx >> SCALE_BITS, ty >> SCALE_BITS);
}
offset++;
tx += dtx;
ty += dty;
depth += dDepth;
}
x += INTERP_SIZE;
} else {
// variable interpolation size
int interpSize = maxLength;
u += interpSize * SCALE * a.x;
v += interpSize * SCALE * b.x;
z += interpSize * c.x;
nextTx = (int) (u / z);
nextTy = (int) (v / z);
// make sure tx, ty, nextTx, and nextTy are
// all within bounds
tx = checkBounds(tx, texture.getWidth());
ty = checkBounds(ty, texture.getHeight());
nextTx = checkBounds(nextTx, texture.getWidth());
nextTy = checkBounds(nextTy, texture.getHeight());
int dtx = (nextTx - tx) / interpSize;
int dty = (nextTy - ty) / interpSize;
int endOffset = offset + interpSize;
while (offset < endOffset) {
if (zBuffer.checkDepth(offset, (short) (depth >> SCALE_BITS))) {
doubleBufferData[offset] = texture.getColor(tx >> SCALE_BITS, ty >> SCALE_BITS);
}
offset++;
tx += dtx;
ty += dty;
depth += dDepth;
}
x += interpSize;
}
}
}
public void parseLine(String line)
throws IOException, NumberFormatException, NoSuchElementException {
StringTokenizer tokenizer = new StringTokenizer(line);
String command = tokenizer.nextToken();
if (command.equals("v")) {
// create a new vertex
vertices.add(
new Vector3D(
Float.parseFloat(tokenizer.nextToken()),
Float.parseFloat(tokenizer.nextToken()),
Float.parseFloat(tokenizer.nextToken())));
} else if (command.equals("f")) {
// create a new face (flat, convex polygon)
List currVertices = new ArrayList();
while (tokenizer.hasMoreTokens()) {
String indexStr = tokenizer.nextToken();
// ignore texture and normal coords
int endIndex = indexStr.indexOf('/');
if (endIndex != -1) {
indexStr = indexStr.substring(0, endIndex);
}
currVertices.add(getVector(indexStr));
}
// create textured polygon
Vector3D[] array = new Vector3D[currVertices.size()];
currVertices.toArray(array);
TexturedPolygon3D poly = new TexturedPolygon3D(array);
// set the texture
ShadedSurface.createShadedSurface(
poly, currentMaterial.texture, lights, ambientLightIntensity);
// add the polygon to the current group
currentGroup.addPolygon(poly);
} else if (command.equals("g")) {
// define the current group
if (tokenizer.hasMoreTokens()) {
String name = tokenizer.nextToken();
currentGroup = new PolygonGroup(name);
} else {
currentGroup = new PolygonGroup();
}
object.addPolygonGroup(currentGroup);
} else if (command.equals("mtllib")) {
// load materials from file
String name = tokenizer.nextToken();
parseFile(name);
} else if (command.equals("usemtl")) {
// define the current material
String name = tokenizer.nextToken();
currentMaterial = (Material) materials.get(name);
if (currentMaterial == null) {
System.out.println("no material: " + name);
}
} else {
// unknown command - ignore it
}
}