public function intersect($ray)
{
$info = new RayTracer_IntersectionInfo();
$Vd = $this->position->dot($ray->direction);
if ($Vd == 0) {
return $info;
}
// no intersection
$t = -($this->position->dot($ray->position) + $this->d) / $Vd;
if ($t <= 0) {
return $info;
}
$info->shape = $this;
$info->isHit = true;
$info->position = RayTracer_Vector::add($ray->position, RayTracer_Vector::multiplyScalar($ray->direction, $t));
$info->normal = $this->position;
$info->distance = $t;
if ($this->material->hasTexture) {
$vU = new RayTracer_Vector($this->position->y, $this->position->z, -$this->position->x);
$vV = $vU->cross($this->position);
$u = $info->position->dot($vU);
$v = $info->position->dot($vV);
$info->color = $this->material->getColor($u, $v);
} else {
$info->color = $this->material->getColor(0, 0);
}
return $info;
}
public function getRay($vx, $vy)
{
$pos = RayTracer_Vector::subtract($this->screen, RayTracer_Vector::subtract(RayTracer_Vector::multiplyScalar($this->equator, $vx), RayTracer_Vector::multiplyScalar($this->up, $vy)));
$pos->y = $pos->y * -1;
$dir = RayTracer_Vector::subtract($pos, $this->position);
$ray = new RayTracer_Ray($pos, $dir->normalize());
return $ray;
}
function renderScene()
{
$scene = new RayTracer_Scene();
$scene->camera = new RayTracer_Camera(new RayTracer_Vector(0, 0, -15), new RayTracer_Vector(-0.2, 0, 5), new RayTracer_Vector(0, 1, 0));
$scene->background = new RayTracer_Background(new RayTracer_Color(0.5, 0.5, 0.5), 0.4);
$sphere = new RayTracer_Shape_Sphere(new RayTracer_Vector(-1.5, 1.5, 2), 1.5, new RayTracer_Material_Solid(new RayTracer_Color(0, 0.5, 0.5), 0.3, 0.0, 0.0, 2.0));
$sphere1 = new RayTracer_Shape_Sphere(new RayTracer_Vector(1, 0.25, 1), 0.5, new RayTracer_Material_Solid(new RayTracer_Color(0.9, 0.9, 0.9), 0.1, 0.0, 0.0, 1.5));
$v = new RayTracer_Vector(0.1, 0.9, -0.5);
$plane = new RayTracer_Shape_Plane($v->normalize(), 1.2, new RayTracer_Material_Chessboard(new RayTracer_Color(1.0, 1.0, 1.0), new RayTracer_Color(0.0, 0.0, 0.0), 0.2, 0.0, 1.0, 0.7));
$scene->shapes[] = $plane;
$scene->shapes[] = $sphere;
$scene->shapes[] = $sphere1;
$light = new RayTracer_Light(new RayTracer_Vector(5, 10, -1), new RayTracer_Color(0.8, 0.8, 0.8));
$light1 = new RayTracer_Light(new RayTracer_Vector(-3, 5, -15), new RayTracer_Color(0.8, 0.8, 0.8), 100);
$scene->lights[] = $light;
$scene->lights[] = $light1;
$imageWidth = 100;
// $F('imageWidth');
$imageHeight = 100;
// $F('imageHeight');
$pixelSize = split(',', "5,5");
// $F('pixelSize').split(',');
$renderDiffuse = true;
// $F('renderDiffuse');
$renderShadows = true;
// $F('renderShadows');
$renderHighlights = true;
// $F('renderHighlights');
$renderReflections = true;
// $F('renderReflections');
$rayDepth = 2;
//$F('rayDepth');
$raytracer = new RayTracer_Engine(array("canvasWidth" => $imageWidth, "canvasHeight" => $imageHeight, "pixelWidth" => $pixelSize[0], "pixelHeight" => $pixelSize[1], "renderDiffuse" => $renderDiffuse, "renderHighlights" => $renderHighlights, "renderShadows" => $renderShadows, "renderReflections" => $renderReflections, "rayDepth" => $rayDepth));
// Create a 55x30 image
//$im = imagecreatetruecolor(500, 500);
$im = null;
$raytracer->renderScene($scene, $im, 0);
/*
// Save the image
imagepng($im, './imagefilledrectangle.png');
imagedestroy($im);
*/
}
public function intersect($ray)
{
$info = new RayTracer_IntersectionInfo();
$info->shape = $this;
$dst = RayTracer_Vector::subtract($ray->position, $this->position);
$B = $dst->dot($ray->direction);
$C = $dst->dot($dst) - $this->radius * $this->radius;
$D = $B * $B - $C;
if ($D > 0) {
// intersection!
$info->isHit = true;
$info->distance = -$B - sqrt($D);
$info->position = RayTracer_Vector::add($ray->position, RayTracer_Vector::multiplyScalar($ray->direction, $info->distance));
$info->normal = RayTracer_Vector::subtract($info->position, $this->position)->normalize();
$info->color = $this->material->getColor(0, 0);
} else {
$info->isHit = false;
}
return $info;
}
public function rayTrace(RayTracer_IntersectionInfo $info, RayTracer_Ray $ray, RayTracer_Scene $scene, $depth)
{
// Calc ambient
$color = RayTracer_Color::multiplyScalar($info->color, $scene->background->ambience);
$shininess = pow(10, $info->shape->material->gloss + 1);
foreach ($scene->lights as $light) {
// Calc diffuse lighting
$v = RayTracer_Vector::subtract($light->position, $info->position)->normalize();
if ($this->options['renderDiffuse']) {
$L = $v->dot($info->normal);
if ($L > 0.0) {
$color = RayTracer_Color::add($color, RayTracer_Color::multiply($info->color, RayTracer_Color::multiplyScalar($light->color, $L)));
}
}
// The greater the depth the more accurate the colours, but
// this is exponentially (!) expensive
if ($depth <= $this->options['rayDepth']) {
// calculate reflection ray
if ($this->options['renderReflections'] && $info->shape->material->reflection > 0) {
$reflectionRay = $this->getReflectionRay($info->position, $info->normal, $ray->direction);
$refl = $this->testIntersection($reflectionRay, $scene, $info->shape);
if ($refl->isHit && $refl->distance > 0) {
$refl->color = $this->rayTrace($refl, $reflectionRay, $scene, $depth + 1);
} else {
$refl->color = $scene->background->color;
}
$color = RayTracer_Color::blend($color, $refl->color, $info->shape->material->reflection);
}
// Refraction
/* TODO */
}
/* Render shadows and highlights */
$shadowInfo = new RayTracer_IntersectionInfo();
if ($this->options['renderShadows']) {
$shadowRay = new RayTracer_Ray($info->position, $v);
$shadowInfo = $this->testIntersection($shadowRay, $scene, $info->shape);
if ($shadowInfo->isHit && $shadowInfo->shape != $info->shape) {
$vA = RayTracer_Color::multiplyScalar($color, 0.5);
$dB = 0.5 * pow($shadowInfo->shape->material->transparency, 0.5);
$color = RayTracer_Color::addScalar($vA, $dB);
}
}
// Phong specular highlights
if ($this->options['renderHighlights'] && !$shadowInfo->isHit && $info->shape->material->gloss > 0) {
$Lv = RayTracer_Vector::subtract($info->shape->position, $light->position)->normalize();
$E = RayTracer_Vector::subtract($scene->camera->position, $info->shape->position)->normalize();
$H = RayTracer_Vector::subtract($E, $Lv)->normalize();
$glossWeight = pow(max($info->normal->dot($H), 0), $shininess);
$color = RayTracer_Color::add(RayTracer_Color::multiplyScalar($light->color, $glossWeight), $color);
}
}
$color->limit();
return $color;
}
