public void AddSample(ImageSample sample)
{
int previousCount = Samples.Count;
Samples.Add(sample);
int diff = Samples.Count - previousCount;
if (diff > 0)
{
// add sample only if it is not a duplicate
SampleMap.Add(sample.Y * Width + sample.X, sample);
}
}
public static ImageSample bilerp(ImageSample result, ImageSample i00, ImageSample i01, ImageSample i10, ImageSample i11, float dx, float dy)
{
float k00 = (1.0f - dx) * (1.0f - dy);
float k01 = (1.0f - dx) * dy;
float k10 = dx * (1.0f - dy);
float k11 = dx * dy;
Color c00 = i00.c;
Color c01 = i01.c;
Color c10 = i10.c;
Color c11 = i11.c;
Color c = Color.mul(k00, c00);
c.madd(k01, c01);
c.madd(k10, c10);
c.madd(k11, c11);
result.c = c;
result.alpha = k00 * i00.alpha + k01 * i01.alpha + k10 * i10.alpha + k11 * i11.alpha;
return result;
}
public bool isDifferent(ImageSample sample, float thresh)
{
if (instance != sample.instance)
return true;
if (shader != sample.shader)
return true;
if (Color.hasContrast(c, sample.c, thresh))
return true;
if (Math.Abs(alpha - sample.alpha) / (alpha + sample.alpha) > thresh)
return true;
// only compare normals if this pixel has not been averaged
float dot = (nx * sample.nx + ny * sample.ny + nz * sample.nz);
return dot < 0.9f;
}
private void refineSamples(ImageSample[] samples, int sbw, int x, int y, int stepSize, float thresh, IntersectionState istate)
{
int dx = stepSize;
int dy = stepSize * sbw;
int i00 = x + y * sbw;
ImageSample s00 = samples[i00];
ImageSample s01 = samples[i00 + dy];
ImageSample s10 = samples[i00 + dx];
ImageSample s11 = samples[i00 + dx + dy];
if (!s00.sampled())
computeSubPixel(s00, istate);
if (!s01.sampled())
computeSubPixel(s01, istate);
if (!s10.sampled())
computeSubPixel(s10, istate);
if (!s11.sampled())
computeSubPixel(s11, istate);
if (stepSize > minStepSize)
{
if (s00.isDifferent(s01, thresh) || s00.isDifferent(s10, thresh) || s00.isDifferent(s11, thresh) || s01.isDifferent(s11, thresh) || s10.isDifferent(s11, thresh) || s01.isDifferent(s10, thresh))
{
stepSize >>= 1;
thresh *= 2;
refineSamples(samples, sbw, x, y, stepSize, thresh, istate);
refineSamples(samples, sbw, x + stepSize, y, stepSize, thresh, istate);
refineSamples(samples, sbw, x, y + stepSize, stepSize, thresh, istate);
refineSamples(samples, sbw, x + stepSize, y + stepSize, stepSize, thresh, istate);
return;
}
}
// interpolate remaining samples
float ds = 1.0f / stepSize;
for (int i = 0; i <= stepSize; i++)
for (int j = 0; j <= stepSize; j++)
if (!samples[x + i + (y + j) * sbw].processed())
ImageSample.bilerp(samples[x + i + (y + j) * sbw], s00, s01, s10, s11, i * ds, j * ds);
}
private void computeSubPixel(ImageSample sample, IntersectionState istate)
{
float x = sample.rx;
float y = sample.ry;
double q0 = QMC.halton(1, sample.i);
double q1 = QMC.halton(2, sample.i);
double q2 = QMC.halton(3, sample.i);
if (superSampling > 1)
{
// multiple sampling
sample.add(scene.getRadiance(istate, x, y, q1, q2, q0, sample.i, 4, null));
for (int i = 1; i < superSampling; i++)
{
double time = QMC.mod1(q0 + i * invSuperSampling);
double lensU = QMC.mod1(q1 + QMC.halton(0, i));
double lensV = QMC.mod1(q2 + QMC.halton(1, i));
sample.add(scene.getRadiance(istate, x, y, lensU, lensV, time, sample.i + i, 4, null));
}
sample.scale((float)invSuperSampling);
}
else
{
// single sample
sample.set(scene.getRadiance(istate, x, y, q1, q2, q0, sample.i, 4, null));
}
}
private void renderBucket(IDisplay display, int bx, int by, int threadID, IntersectionState istate)
{
// pixel sized extents
int x0 = bx * bucketSize;
int y0 = by * bucketSize;
int bw = Math.Min(bucketSize, imageWidth - x0);
int bh = Math.Min(bucketSize, imageHeight - y0);
// prepare bucket
display.imagePrepare(x0, y0, bw, bh, threadID);
Color[] bucketRGB = new Color[bw * bh];
float[] bucketAlpha = new float[bw * bh];
// subpixel extents
int sx0 = x0 * subPixelSize - fs;
int sy0 = y0 * subPixelSize - fs;
int sbw = bw * subPixelSize + fs * 2;
int sbh = bh * subPixelSize + fs * 2;
// round up to align with maximum step size
sbw = (sbw + (maxStepSize - 1)) & (~(maxStepSize - 1));
sbh = (sbh + (maxStepSize - 1)) & (~(maxStepSize - 1));
// extra padding as needed
if (maxStepSize > 1)
{
sbw++;
sbh++;
}
// allocate bucket memory
ImageSample[] samples = new ImageSample[sbw * sbh];
// allocate samples and compute jitter offsets
float invSubPixelSize = 1.0f / subPixelSize;
for (int y = 0, index = 0; y < sbh; y++)
{
for (int x = 0; x < sbw; x++, index++)
{
int sx = sx0 + x;
int sy = sy0 + y;
int j = sx & (sigmaLength - 1);
int k = sy & (sigmaLength - 1);
int i = (j << sigmaOrder) + QMC.sigma(k, sigmaOrder);
float dx = useJitter ? (float) QMC.halton(0, k) : 0.5f;
float dy = useJitter ? (float) QMC.halton(0, j) : 0.5f;
float rx = (sx + dx) * invSubPixelSize;
float ry = (sy + dy) * invSubPixelSize;
ry = imageHeight - ry;
samples[index] = new ImageSample(rx, ry, i);
}
}
for (int x = 0; x < sbw - 1; x += maxStepSize)
for (int y = 0; y < sbh - 1; y += maxStepSize)
refineSamples(samples, sbw, x, y, maxStepSize, thresh, istate);
if (dumpBuckets)
{
UI.printInfo(UI.Module.BCKT, "Dumping bucket [{0}, {1}] to file ...", bx, by);
GenericBitmap bitmap = new GenericBitmap(sbw, sbh);
for (int y = sbh - 1, index = 0; y >= 0; y--)
for (int x = 0; x < sbw; x++, index++)
bitmap.writePixel(x, y, samples[index].c, samples[index].alpha);
bitmap.save(string.Format("bucket_{0}_{1}.png", bx, by));
}
if (displayAA)
{
// color coded image of what is visible
float invArea = invSubPixelSize * invSubPixelSize;
for (int y = 0, index = 0; y < bh; y++)
{
for (int x = 0; x < bw; x++, index++)
{
int sampled = 0;
for (int i = 0; i < subPixelSize; i++)
{
for (int j = 0; j < subPixelSize; j++)
{
int sx = x * subPixelSize + fs + i;
int sy = y * subPixelSize + fs + j;
int s = sx + sy * sbw;
sampled += samples[s].sampled() ? 1 : 0;
}
}
bucketRGB[index] = new Color(sampled * invArea);
bucketAlpha[index] = 1.0f;
}
}
}
else
{
// filter samples into pixels
float cy = imageHeight - (y0 + 0.5f);
for (int y = 0, index = 0; y < bh; y++, cy--)
{
float cx = x0 + 0.5f;
for (int x = 0; x < bw; x++, index++, cx++)
{
Color c = Color.black();
float a = 0.0f;
float weight = 0.0f;
for (int j = -fs, sy = y * subPixelSize; j <= fs; j++, sy++)
{
for (int i = -fs, sx = x * subPixelSize, s = sx + sy * sbw; i <= fs; i++, sx++, s++)
{
float dx = samples[s].rx - cx;
if (Math.Abs(dx) > fhs)
continue;
float dy = samples[s].ry - cy;
if (Math.Abs(dy) > fhs)
continue;
float f = filter.get(dx, dy);
c.madd(f, samples[s].c);
a += f * samples[s].alpha;
weight += f;
}
}
float invWeight = 1.0f / weight;
c.mul(invWeight);
a *= invWeight;
bucketRGB[index] = c;
bucketAlpha[index] = a;
}
}
}
// update pixels
display.imageUpdate(x0, y0, bw, bh, bucketRGB, bucketAlpha);
}