Point *findIntersectionPoint(Ray ray, Sphere sphere) {
Vector sphereToRay = fromToVector(sphere.center, ray.point);
double a = dotVector(ray.direction, ray.direction);
double b = dotVector(scaleVector(sphereToRay, 2.0), ray.direction);
double c = dotVector(sphereToRay, sphereToRay) - sphere.radius * sphere.radius;
double determinant = b * b - 4 * a * c;
if (determinant >= 0) {
double root1 = (-b + sqrt(determinant)) / (2.0 * a);
double root2 = (-b - sqrt(determinant)) / (2.0 * a);
if (root1 >= 0 && root2 >= 0) {
return findPointFromRoot(min(root1, root2), ray);
} else if (root1 >= 0 || root2 >= 0) {
return findPointFromRoot(max(root1, root2), ray);
}
return (Point *) NULL;
}
return (Point *) NULL;
}
Color shadeWithMaterial(struct Scene* scene, struct HitRecord* record, Ray ray, int depth) {
Color result = {0,0,0};
Material material = *record->triangle->material;
struct HitRecord temp_record = createHitRecord();
Vector position = record->point;
Vector new_direction;
if(depth == scene->max_depth) {
return result;
}
if(material.is_light) {
return material.color;
}
Vector normal = record->triangle->normal;
float costheta = dotVector(normal, ray.direction);
if(costheta > 0) {
normal = negateVector(normal);
}
float path = (double)rand()/(double)RAND_MAX;
// diffuse BRDF
if(path < .33) {
new_direction = getDiffuseDirection(normal);
}
// BRDF (which is also diffuse)
else if(path < .66) {
new_direction = getDiffuseDirection(normal);
}
// point to light
else {
new_direction = getLightDirection(scene, position);
}
Ray new_ray = {position, new_direction};
resetHitRecord(&temp_record);
float cosphi = dotVector(normal, new_direction);
if(cosphi > 0) {
result = addColors(result, multiplyColorByNumber(hitScene(scene, &temp_record, new_ray, depth + 1), cosphi));
}
return multiplyColors(result, material.color);
}
void QgsDxfExport::writeDefaultLinestyles()
{
double das = dashSize();
double dos = dotSize();
double dss = dashSeparatorSize();
//continuous (Qt solid line)
writeGroup( 0, "LTYPE" );
writeGroup( 2, "CONTINUOUS" );
writeGroup( 70, 64 );
writeGroup( 3, "Defaultstyle" );
writeGroup( 72, 65 );
writeGroup( 73, 0 );
writeGroup( 40, 0.0 );
QVector<qreal> dashVector( 2 );
dashVector[0] = das;
dashVector[1] = dss;
writeLinestyle( "DASH", dashVector, QgsSymbolV2::MapUnit );
QVector<qreal> dotVector( 2 );
dotVector[0] = dos;
dotVector[1] = dss;
writeLinestyle( "DOT", dotVector, QgsSymbolV2::MapUnit );
QVector<qreal> dashDotVector( 4 );
dashDotVector[0] = das;
dashDotVector[1] = dss;
dashDotVector[2] = dos;
dashDotVector[3] = dss;
writeLinestyle( "DASHDOT", dashDotVector, QgsSymbolV2::MapUnit );
QVector<qreal> dashDotDotVector( 6 );
dashDotDotVector[0] = das;
dashDotDotVector[1] = dss;
dashDotDotVector[2] = dos;
dashDotDotVector[3] = dss;
dashDotDotVector[4] = dos;
dashDotDotVector[5] = dss;
writeLinestyle( "DASHDOTDOT", dashDotDotVector, QgsSymbolV2::MapUnit );
}
double normVector(Vector3 a) {
return sqrt(dotVector(a, a));
}
