/**
* @param scene
* @param ray
* @return <code>true</code> if exited water
*/
private boolean exitWater(Scene scene, Ray ray) {
int level;
Octree.Node node;
int lx, ly, lz;
int x, y, z;
double nx, ny, nz;
double xx, xy, xz;
double cx, cy, cz, cw;
double distance;
while (true) {
Block.WATER.intersect(ray, scene);
ray.n.x = -ray.n.x;
ray.n.y = -ray.n.y;
ray.n.z = -ray.n.z;
xx = ray.x.x;
xy = ray.x.y;
xz = ray.x.z;
nx = ray.n.x;
ny = ray.n.y;
nz = ray.n.z;
cx = ray.color.x;
cy = ray.color.y;
cz = ray.color.z;
cw = ray.color.w;
distance = ray.distance;
// add small offset past the intersection to avoid
// recursion to the same octree node!
x = (int) QuickMath.floor(ray.x.x + ray.d.x * Ray.OFFSET);
y = (int) QuickMath.floor(ray.x.y + ray.d.y * Ray.OFFSET);
z = (int) QuickMath.floor(ray.x.z + ray.d.z * Ray.OFFSET);
node = root;
level = depth;
lx = x >>> level;
ly = y >>> level;
lz = z >>> level;
if (lx != 0 || ly != 0 || lz != 0) {
// ray origin is outside octree!
ray.currentMaterial = Block.AIR.id;
return true;
}
while (node.type == -1) {
level -= 1;
lx = x >>> level;
ly = y >>> level;
lz = z >>> level;
node = node.children[((lx & 1) << 2) | ((ly & 1) << 1) | (lz & 1)];
}
Block currentBlock = Block.get(node.type);
Block prevBlock = Block.get(ray.currentMaterial);
ray.prevMaterial = ray.currentMaterial;
ray.currentMaterial = node.type;
if (currentBlock.localIntersect) {
if (!currentBlock.intersect(ray, scene)) {
ray.currentMaterial = Block.AIR.id;
return true;
}
if (ray.distance > distance) {
ray.x.set(xx, xy, xz);
ray.n.set(nx, ny, nz);
ray.color.set(cx, cy, cz, cw);
ray.distance = distance;
ray.currentMaterial = Block.AIR.id;
return true;
} else if (currentBlock == Block.WATER) {
ray.x.scaleAdd(Ray.OFFSET, ray.d, ray.x);
continue;
} else {
return true;
}
}
if (currentBlock != prevBlock) {
TexturedBlockModel.getIntersectionColor(ray);
ray.n.scale(-1);
return true;
}
}
}
/**
* Test whether the ray intersects any voxel before exiting the Octree.
*
* @param scene
* @param ray the ray
* @return <code>true</code> if the ray intersects a voxel
*/
public boolean intersect(Scene scene, Ray ray) {
int level;
Octree.Node node;
boolean first = true;
int lx, ly, lz;
int x, y, z;
int nx = 0, ny = 0, nz = 0;
double tNear = Double.POSITIVE_INFINITY;
double t;
Vector3d d = ray.d;
while (true) {
// add small offset past the intersection to avoid
// recursion to the same octree node!
x = (int) QuickMath.floor(ray.x.x + ray.d.x * Ray.OFFSET);
y = (int) QuickMath.floor(ray.x.y + ray.d.y * Ray.OFFSET);
z = (int) QuickMath.floor(ray.x.z + ray.d.z * Ray.OFFSET);
node = root;
level = depth;
lx = x >>> level;
ly = y >>> level;
lz = z >>> level;
if (lx != 0 || ly != 0 || lz != 0) {
// ray origin is outside octree!
ray.currentMaterial = Block.AIR_ID;
// only check octree intersection if this is the first iteration
if (first) {
// test if it is entering the octree
t = -ray.x.x / d.x;
if (t > Ray.EPSILON) {
tNear = t;
nx = 1;
ny = nz = 0;
}
t = ((1 << level) - ray.x.x) / d.x;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
nx = -1;
ny = nz = 0;
}
t = -ray.x.y / d.y;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
ny = 1;
nx = nz = 0;
}
t = ((1 << level) - ray.x.y) / d.y;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
ny = -1;
nx = nz = 0;
}
t = -ray.x.z / d.z;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
nz = 1;
nx = ny = 0;
}
t = ((1 << level) - ray.x.z) / d.z;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
nz = -1;
nx = ny = 0;
}
if (tNear < Double.MAX_VALUE) {
ray.x.scaleAdd(tNear, d, ray.x);
ray.n.set(nx, ny, nz);
ray.distance += tNear;
tNear = Double.POSITIVE_INFINITY;
continue;
} else {
return false; // outside of octree!
}
} else {
return false; // outside of octree!
}
}
first = false;
while (node.type == -1) {
level -= 1;
lx = x >>> level;
ly = y >>> level;
lz = z >>> level;
node = node.children[((lx & 1) << 2) | ((ly & 1) << 1) | (lz & 1)];
}
// old octree visualization code
/*double w = .1 * (1 + level);
w*=w;
if (ray.x.x < (lx<<level) + w && (ray.x.y < (ly<<level) + w || ray.x.y > ((ly+1)<<level) - w) ||
ray.x.x < (lx<<level) + w && (ray.x.z < (lz<<level) + w || ray.x.z > ((lz+1)<<level) - w) ||
ray.x.y < (ly<<level) + w && (ray.x.z < (lz<<level) + w || ray.x.z > ((lz+1)<<level) - w) ||
ray.x.x > ((lx+1)<<level) - w && (ray.x.y < (ly<<level) + w || ray.x.y > ((ly+1)<<level) - w) ||
ray.x.x > ((lx+1)<<level) - w && (ray.x.z < (lz<<level) + w || ray.x.z > ((lz+1)<<level) - w) ||
ray.x.y > ((ly+1)<<level) - w && (ray.x.z < (lz<<level) + w || ray.x.z > ((lz+1)<<level) - w)) {
ray.color.x = .5;
ray.color.y = .5;
ray.color.z = .5;
ray.color.w = 1;
ray.prevMaterial = Block.AIR.id;
ray.currentMaterial = 0xFF;
return true;
}*/
if (ray.currentMaterial == -1) {
ray.prevMaterial = 0;
ray.currentMaterial = node.type;
}
Block currentBlock = Block.get(node.type);
Block prevBlock = Block.get(ray.currentMaterial);
ray.prevMaterial = ray.currentMaterial;
ray.currentMaterial = node.type;
if (currentBlock.localIntersect) {
if (currentBlock == Block.WATER && prevBlock == Block.WATER) {
return exitWater(scene, ray);
}
if (currentBlock.intersect(ray, scene)) {
if (prevBlock != currentBlock) return true;
ray.x.scaleAdd(Ray.OFFSET, ray.d, ray.x);
continue;
} else {
// exit ray from this local block
ray.currentMaterial = 0; // current material is air
ray.exitBlock(x, y, z);
continue;
}
} else if (!currentBlock.isSameMaterial(prevBlock) && currentBlock != Block.AIR) {
TexturedBlockModel.getIntersectionColor(ray);
return true;
}
t = ((lx << level) - ray.x.x) / d.x;
if (t > Ray.EPSILON) {
tNear = t;
nx = 1;
ny = nz = 0;
} else {
t = (((lx + 1) << level) - ray.x.x) / d.x;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
nx = -1;
ny = nz = 0;
}
}
t = ((ly << level) - ray.x.y) / d.y;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
ny = 1;
nx = nz = 0;
} else {
t = (((ly + 1) << level) - ray.x.y) / d.y;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
ny = -1;
nx = nz = 0;
}
}
t = ((lz << level) - ray.x.z) / d.z;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
nz = 1;
nx = ny = 0;
} else {
t = (((lz + 1) << level) - ray.x.z) / d.z;
if (t < tNear && t > Ray.EPSILON) {
tNear = t;
nz = -1;
nx = ny = 0;
}
}
ray.x.scaleAdd(tNear, d, ray.x);
ray.n.set(nx, ny, nz);
ray.distance += tNear;
tNear = Double.POSITIVE_INFINITY;
}
}
