31 

    32 int DefaultSampler::initSampleSet()

    33 {

    34 	if ( phase == 0 )

    35 	{

    36 		phase++;

    37 		return w*h;

    38 	}

    39 	else return 0;

    40 }

    41 

    42 Sample* DefaultSampler::nextSample(Sample *prev)

    43 {

    44 	DefaultSample *s = new DefaultSample;

    45 	if (prev)

    46 	{

    47 		DefaultSample *sp = static_cast<DefaultSample*>(prev);

    48 		s->sx = sp->sx + 1;

    49 		s->sy = sp->sy;

    50 		if (s->sx >= w)

    51 		{

    52 			s->sx = 0;

    53 			s->sy++;

    54 		}

    55 		if (s->sy >= h)

    56 		{

    57 			delete s;

    58 			return NULL;

    59 		}

    60 		s->x = (Float)s->sx/h - (Float)w/h/2.0;

    61 		s->y = (Float)s->sy/h - 0.5;

    62 	}

    63 	else

    64 	{

    65 		s->x = -(Float)w/h/2.0;

    66 		s->y = -0.5;

    67 		s->sx = 0;

    68 		s->sy = 0;

    69 	}

    70 	return s;

    71 }

    72 

    73 void DefaultSampler::saveSample(Sample *samp, Colour &col)

    74 {

    75 	DefaultSample *sp = static_cast<DefaultSample*>(samp);

    76 	Float *buf = buffer + 3*(sp->sy*w + sp->sx);

    77 	*(buf++) = col.r;

    78 	*(buf++) = col.g;

    79 	*(buf++) = col.b;

    80 }

   128 Ray Camera::makeRay(Sample *samp)

   129 {

   130 	Vector3 dir = p + u*(0.5/f)*samp->x + v*(-0.5/f)*samp->y;

   131 	dir.normalize();

   132 	return Ray(eye, dir);

   133 }

   134