// Display checker board background
MaterialCell checkerBackgroundHit(Ray r, HitRecord hit) {
// Find the t value where z = scene.camera.far
hit.t = -scene.camera.far / r.dir.z;
if (hit.t < 0) // Only put it on the background, not behind the camera too
return black;
hit.hitP = r.pointAtParameter(hit.t);
hit.normal = new Double3D(0, 0, 1);
hit.hitP.x = (hit.hitP.x > 0) ? hit.hitP.x : -hit.hitP.x + checkerFreq / 2;
hit.hitP.y = (hit.hitP.y > 0) ? hit.hitP.y : -hit.hitP.y + checkerFreq / 2;
if (hit.hitP.x % checkerFreq < checkerFreq / 2) // && p.x < scene.camera.windowRight)
if (hit.hitP.y % checkerFreq < checkerFreq / 2) // && p.y < scene.camera.windowTop)
return white;
else return black;
else if (hit.hitP.y % checkerFreq < checkerFreq / 2) // && p.y < scene.camera.windowTop)
return black;
else return white;
}
// All rays we deal with here are in world coordinates.
// Should take the refractive index of the material it is currently in.
DoubleColor trace(Ray ray) {
DoubleColor color = new DoubleColor(0.0, 0.0, 0.0, 1.0);
HitRecord hit = new HitRecord();
if (depth > Math.max(DEBUG_recursion, scene.maxRecursiveDepth)) return color;
double tMin = 0.0001;
double tMax = 10000000;
// Spheres only for now
for (int i = 0; i < numObjects; i++)
// Did I hit the bounding sphere for an object?
if (spheres[i].hit(ray, tMin, tMax, 0, hit))
if (scene.spheresOnly) {
for (PMesh.SurfCell s = shapes[i].surfHead; s != null; s = s.next)
for (PMesh.PolyCell poly = s.polyHead; poly != null; poly = poly.next)
// Triangles only for now
if (poly.numVerts == 3) {
Double3D v[] = new Double3D[3];
int j = 0;
for (PMesh.VertListCell vert = poly.vert; vert != null; vert = vert.next)
v[j++] = shapes[i].vertArray.get(vert.vert).viewPos;
// Increment j in the line post access
// Check for a hit on this polygon
if (Triangle.hit(v[0], v[1], v[2], ray, tMin, tMax, 0, hit)) {
tMax = hit.t;
hit.normal = poly.viewNorm;
hit.matIndex = s.material;
hit.index = i;
}
} else
System.out.println(
"Need to intersect polygon with " + poly.numVerts + " vertices.");
} else {
tMax = hit.t;
hit.matIndex = i; // May cause an error if object 10 and it only has 3 materials.
hit.index = i;
}
if (hit.index >= 0) // If it intersects then multi-sample
{
if (!sampled && depth == 0) {
// Only sample once per ray from the main loop
sampled = true;
Double3D dir = ray.dir;
DoubleColor antiAlias = trace(ray);
for (int i = 0; i < samples; i++) {
// Double3D sample = new Double3D(dir.x + imageSamples[i].x, dir.y + imageSamples[i].y,
// dir.z).getUnit();
// ray.dir = sample;
ray.dir.x = dir.x + imageSamples[i].x;
ray.dir.y = dir.y + imageSamples[i].y;
antiAlias.plus(trace(ray));
}
antiAlias.scale(1.0 / (samples + 1.0));
color.plus(antiAlias);
} else if (hit.matIndex < shapes[hit.index].materials.length)
color = shade(ray, hit, shapes[hit.index].materials[hit.matIndex], false);
else
color =
shade(
ray,
hit,
shapes[hit.index].materials[shapes[hit.index].materials.length - 1],
false);
} else // We hit nothing check for intersection with the far clip plane for checker board
// pattern.
if (scene.checkerBackground) color = shade(ray, hit, checkerBackgroundHit(ray, hit), true);
return color;
}