josh/fart
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

updated Cyl intersection routine

Browse Source 
git-svn-id: svn://anubis/fart/trunk@132 7f9b0f55-74a9-4bce-be96-3c2cd072584d
This commit is contained in:
Josh Holtrop 2009-02-19 18:03:23 +00:00
parent d8648b0770
commit 39e77678ee
1 changed files with 52 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

57
shapes/Cyl.cc
View File

@ -22,9 +22,44 @@ Cyl::Cyl(double bottom_radius, double top_radius, double height)
Shape::IntersectList Cyl::intersect(const Ray & ray)
{
Ray ray_inv = m_inverse.transform_ray(ray);
IntersectList res;
/* First intersect with the bottom plane, if it has positive area */
if (m_bottom_radius > 0.0)
{
LinearSolver solver(-ray_inv.getDirection()[2],
-ray_inv.getOrigin()[2]);
Solver::Result solutions = solver.solve();
if (solutions.numResults > 0)
{
Vector isect_point = ray_inv[solutions.results[0]];
if (isect_point[0]*isect_point[0] + isect_point[1]*isect_point[1]
< m_bottom_radius_2)
{
res.push_back(m_transform.transform_point(isect_point));
}
}
}
/* Same for the top plane */
if (m_top_radius > 0.0)
{
LinearSolver solver(ray_inv.getDirection()[2],
ray_inv.getOrigin()[2] + m_height);
Solver::Result solutions = solver.solve();
if (solutions.numResults > 0)
{
Vector isect_point = ray_inv[solutions.results[0]];
if (isect_point[0]*isect_point[0] + isect_point[1]*isect_point[1]
< m_top_radius_2)
{
res.push_back(m_transform.transform_point(isect_point));
}
}
}
/*
* Now see if the ray hit the side of the cylinder/cone thingy
* Ray equation: R = R0 + tRd
* x = R0x + tRdx
* y = R0y + tRdy
@ -47,15 +82,27 @@ Shape::IntersectList Cyl::intersect(const Ray & ray)
double R0x = ray_inv.getOrigin()[0];
double R0y = ray_inv.getOrigin()[1];
double R0z = ray_inv.getOrigin()[2];
double m = m_m;
double m = m_slope;
double m2 = m*m;
double b = m_bottom_radius;
QuadraticSolver solver(Rdx * Rdx + Rdy * Rdy - m2 * Rdz * Rdz,
2.0 * (R0x*Rdx + R0y*Rdy - m2*R0z*Rdz - m*Rdz*m_b),
2.0 * (R0x*Rdx + R0y*Rdy - m2*R0z*Rdz - m*Rdz*b),
R0x*R0x + R0y*R0y
- m2*R0z*R0z - m_b*m_b - 2*m*R0z*m_b
- m2*R0z*R0z - b*b - 2*m*R0z*b
);
Solver::Results results = solver.solve();
Solver::Result solutions = solver.solve();
for (int i = 0; i < solutions.numResults; i++)
{
if (solutions.results[i] >= 0.0)
{
Vector isect_point = ray_inv[solutions.results[i]];
if (isect_point[2] >= 0.0 && isect_point[2] <= m_height)
{
res.push_back(m_transform.transform_point(isect_point));
}
}
}
return res;
}