diff options
author | click <none@none> | 2010-08-27 01:52:05 +0200 |
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committer | click <none@none> | 2010-08-27 01:52:05 +0200 |
commit | 7686d6ee57038e848f75130563fc78c1adebc1a2 (patch) | |
tree | 258a7a6db03e3479a0219ace8cfc3ec3ba53a1be /dep/g3dlite/source/Triangle.cpp | |
parent | 1d3deae555f0ec523d77875bd5a307ab9bd19742 (diff) |
Core/Dependency: Upgrade G3d-library to v8.0-release (patched version!)
Note: Due to issues with G3D (normally requiring X11 and the ZIP-library),
the sourcetree version contains a modified version. The applied patch is
commited to the repository for future reference.
--HG--
branch : trunk
Diffstat (limited to 'dep/g3dlite/source/Triangle.cpp')
-rw-r--r-- | dep/g3dlite/source/Triangle.cpp | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/dep/g3dlite/source/Triangle.cpp b/dep/g3dlite/source/Triangle.cpp new file mode 100644 index 00000000000..253438ad5fb --- /dev/null +++ b/dep/g3dlite/source/Triangle.cpp @@ -0,0 +1,186 @@ +/** + @file Triangle.cpp + + @maintainer Morgan McGuire, http://graphics.cs.williams.edu + + @created 2001-04-06 + @edited 2008-12-28 + + Copyright 2000-2009, Morgan McGuire. + All rights reserved. + */ + +#include "G3D/platform.h" +#include "G3D/Triangle.h" +#include "G3D/Plane.h" +#include "G3D/BinaryInput.h" +#include "G3D/BinaryOutput.h" +#include "G3D/debugAssert.h" +#include "G3D/AABox.h" +#include "G3D/Ray.h" + +namespace G3D { + + +void Triangle::init(const Vector3& v0, const Vector3& v1, const Vector3& v2) { + + _plane = Plane(v0, v1, v2); + _vertex[0] = v0; + _vertex[1] = v1; + _vertex[2] = v2; + + static int next[] = {1,2,0}; + + for (int i = 0; i < 3; ++i) { + const Vector3& e = _vertex[next[i]] - _vertex[i]; + edgeMagnitude[i] = e.magnitude(); + + if (edgeMagnitude[i] == 0) { + edgeDirection[i] = Vector3::zero(); + } else { + edgeDirection[i] = e / (float)edgeMagnitude[i]; + } + } + + _edge01 = _vertex[1] - _vertex[0]; + _edge02 = _vertex[2] - _vertex[0]; + + _primaryAxis = _plane.normal().primaryAxis(); + _area = 0.5f * edgeDirection[0].cross(edgeDirection[2]).magnitude() * (edgeMagnitude[0] * edgeMagnitude[2]); + //0.5f * (_vertex[1] - _vertex[0]).cross(_vertex[2] - _vertex[0]).dot(_plane.normal()); +} + + +Triangle::Triangle() { + init(Vector3::zero(), Vector3::zero(), Vector3::zero()); +} + + +Triangle::Triangle(const Vector3& v0, const Vector3& v1, const Vector3& v2) { + init(v0, v1, v2); +} + + +Triangle::~Triangle() { +} + + +Triangle::Triangle(class BinaryInput& b) { + deserialize(b); +} + + +void Triangle::serialize(class BinaryOutput& b) { + _vertex[0].serialize(b); + _vertex[1].serialize(b); + _vertex[2].serialize(b); +} + + +void Triangle::deserialize(class BinaryInput& b) { + _vertex[0].deserialize(b); + _vertex[1].deserialize(b); + _vertex[2].deserialize(b); + init(_vertex[0], _vertex[1], _vertex[2]); +} + + +float Triangle::area() const { + return _area; +} + + +const Vector3& Triangle::normal() const { + return _plane.normal(); +} + + +const Plane& Triangle::plane() const { + return _plane; +} + + +Vector3 Triangle::center() const { + return (_vertex[0] + _vertex[1] + _vertex[2]) / 3.0; +} + +Vector3 Triangle::randomPoint() const { + // Choose a random point in the parallelogram + + float s = uniformRandom(); + float t = uniformRandom(); + + if (t > 1.0f - s) { + // Outside the triangle; reflect about the + // diagonal of the parallelogram + t = 1.0f - t; + s = 1.0f - s; + } + + return _edge01 * s + _edge02 * t + _vertex[0]; +} + + +void Triangle::getBounds(AABox& out) const { + Vector3 lo = _vertex[0]; + Vector3 hi = lo; + + for (int i = 1; i < 3; ++i) { + lo = lo.min(_vertex[i]); + hi = hi.max(_vertex[i]); + } + + out = AABox(lo, hi); +} + + +bool Triangle::intersect(const Ray& ray, float& distance, float baryCoord[3]) const { + static const float EPS = 1e-5f; + + // See RTR2 ch. 13.7 for the algorithm. + + const Vector3& e1 = edge01(); + const Vector3& e2 = edge02(); + const Vector3 p(ray.direction().cross(e2)); + const float a = e1.dot(p); + + if (abs(a) < EPS) { + // Determinant is ill-conditioned; abort early + return false; + } + + const float f = 1.0f / a; + const Vector3 s(ray.origin() - vertex(0)); + const float u = f * s.dot(p); + + if ((u < 0.0f) || (u > 1.0f)) { + // We hit the plane of the m_geometry, but outside the m_geometry + return false; + } + + const Vector3 q(s.cross(e1)); + const float v = f * ray.direction().dot(q); + + if ((v < 0.0f) || ((u + v) > 1.0f)) { + // We hit the plane of the triangle, but outside the triangle + return false; + } + + const float t = f * e2.dot(q); + + if ((t > 0.0f) && (t < distance)) { + // This is a new hit, closer than the previous one + distance = t; + + baryCoord[0] = 1.0 - u - v; + baryCoord[1] = u; + baryCoord[2] = v; + + return true; + } else { + // This hit is after the previous hit, so ignore it + return false; + } +} + +} // G3D |