diff options
Diffstat (limited to 'src/Tracer.cpp')
| -rw-r--r-- | src/Tracer.cpp | 90 |
1 files changed, 56 insertions, 34 deletions
diff --git a/src/Tracer.cpp b/src/Tracer.cpp index e604f4a5b..b6b0fd634 100644 --- a/src/Tracer.cpp +++ b/src/Tracer.cpp @@ -12,17 +12,32 @@ +const float FLOAT_EPSILON = 0.0001f; // TODO: Stash this in some header where it can be reused + + +const std::array<const Vector3f, 6>& cTracer::m_NormalTable(void) +{ + static std::array<const Vector3f, 6>* table = + new std::array<const Vector3f, 6> + { + { + Vector3f(-1, 0, 0), // 1: -x + Vector3f( 0, 0, -1), // 2: -z + Vector3f( 1, 0, 0), // 3: +x + Vector3f( 0, 0, 1), // 4: +z + Vector3f( 0, 1, 0), // 5: +y + Vector3f( 0, -1, 0) // 6: -y + } + }; + + return *table; +}; + cTracer::cTracer(cWorld * a_World): m_World(a_World) { - m_NormalTable[0].Set(-1, 0, 0); - m_NormalTable[1].Set( 0, 0, -1); - m_NormalTable[2].Set( 1, 0, 0); - m_NormalTable[3].Set( 0, 0, 1); - m_NormalTable[4].Set( 0, 1, 0); - m_NormalTable[5].Set( 0, -1, 0); } @@ -37,7 +52,7 @@ cTracer::~cTracer() -float cTracer::SigNum(float a_Num) +int cTracer::SigNum(float a_Num) { if (a_Num < 0.f) { @@ -56,26 +71,28 @@ float cTracer::SigNum(float a_Num) void cTracer::SetValues(const Vector3f & a_Start, const Vector3f & a_Direction) { + // Since this method should only be called by Trace, zero length vectors should already have been taken care of + ASSERT(a_Direction.HasNonZeroLength()); + // calculate the direction of the ray (linear algebra) dir = a_Direction; // decide which direction to start walking in - step.x = (int) SigNum(dir.x); - step.y = (int) SigNum(dir.y); - step.z = (int) SigNum(dir.z); + step.x = SigNum(dir.x); + step.y = SigNum(dir.y); + step.z = SigNum(dir.z); + // normalize the direction vector - if (dir.SqrLength() > 0.f) - { - dir.Normalize(); - } + dir.Normalize(); + // how far we must move in the ray direction before // we encounter a new voxel in x-direction // same but y-direction if (dir.x != 0.f) { - tDelta.x = 1 / fabs(dir.x); + tDelta.x = 1 / std::abs(dir.x); } else { @@ -83,7 +100,7 @@ void cTracer::SetValues(const Vector3f & a_Start, const Vector3f & a_Direction) } if (dir.y != 0.f) { - tDelta.y = 1 / fabs(dir.y); + tDelta.y = 1 / std::abs(dir.y); } else { @@ -91,44 +108,45 @@ void cTracer::SetValues(const Vector3f & a_Start, const Vector3f & a_Direction) } if (dir.z != 0.f) { - tDelta.z = 1 / fabs(dir.z); + tDelta.z = 1 / std::abs(dir.z); } else { tDelta.z = 0; } + // start voxel coordinates - pos.x = (int)floorf(a_Start.x); - pos.y = (int)floorf(a_Start.y); - pos.z = (int)floorf(a_Start.z); + pos.x = static_cast<int>(floorf(a_Start.x)); + pos.y = static_cast<int>(floorf(a_Start.y)); + pos.z = static_cast<int>(floorf(a_Start.z)); // calculate distance to first intersection in the voxel we start from if (dir.x < 0) { - tMax.x = ((float)pos.x - a_Start.x) / dir.x; + tMax.x = (static_cast<float>(pos.x) - a_Start.x) / dir.x; } else { - tMax.x = (((float)pos.x + 1) - a_Start.x) / dir.x; + tMax.x = (static_cast<float>(pos.x + 1) - a_Start.x) / dir.x; // TODO: Possible division by zero } if (dir.y < 0) { - tMax.y = ((float)pos.y - a_Start.y) / dir.y; + tMax.y = (static_cast<float>(pos.y) - a_Start.y) / dir.y; } else { - tMax.y = (((float)pos.y + 1) - a_Start.y) / dir.y; + tMax.y = (static_cast<float>(pos.y + 1) - a_Start.y) / dir.y; // TODO: Possible division by zero } if (dir.z < 0) { - tMax.z = ((float)pos.z - a_Start.z) / dir.z; + tMax.z = (static_cast<float>(pos.z) - a_Start.z) / dir.z; } else { - tMax.z = (((float)pos.z + 1) - a_Start.z) / dir.z; + tMax.z = (static_cast<float>(pos.z + 1) - a_Start.z) / dir.z; // TODO: Possible division by zero } } @@ -138,6 +156,11 @@ void cTracer::SetValues(const Vector3f & a_Start, const Vector3f & a_Direction) bool cTracer::Trace(const Vector3f & a_Start, const Vector3f & a_Direction, int a_Distance, bool a_LineOfSight) { + if (!a_Direction.HasNonZeroLength()) + { + return false; + } + if ((a_Start.y < 0) || (a_Start.y >= cChunkDef::Height)) { LOGD("%s: Start Y is outside the world (%.2f), not tracing.", __FUNCTION__, a_Start.y); @@ -146,18 +169,18 @@ bool cTracer::Trace(const Vector3f & a_Start, const Vector3f & a_Direction, int SetValues(a_Start, a_Direction); - Vector3f End = a_Start + (dir * (float)a_Distance); + Vector3f End = a_Start + (dir * static_cast<float>(a_Distance)); if (End.y < 0) { - float dist = -a_Start.y / dir.y; + float dist = -a_Start.y / dir.y; // No division by 0 possible End = a_Start + (dir * dist); } // end voxel coordinates - end1.x = (int)floorf(End.x); - end1.y = (int)floorf(End.y); - end1.z = (int)floorf(End.z); + end1.x = static_cast<int>(floorf(End.x)); + end1.y = static_cast<int>(floorf(End.y)); + end1.z = static_cast<int>(floorf(End.z)); // check if first is occupied if (pos.Equals(end1)) @@ -241,7 +264,7 @@ bool cTracer::Trace(const Vector3f & a_Start, const Vector3f & a_Direction, int int Normal = GetHitNormal(a_Start, End, pos); if (Normal > 0) { - HitNormal = m_NormalTable[Normal-1]; + HitNormal = m_NormalTable()[Normal - 1]; } return true; } @@ -295,8 +318,7 @@ int cTracer::intersect3D_SegmentPlane(const Vector3f & a_Origin, const Vector3f float D = a_PlaneNormal.Dot(u); // dot(Pn.n, u); float N = -(a_PlaneNormal.Dot(w)); // -dot(a_Plane.n, w); - const float EPSILON = 0.0001f; - if (fabs(D) < EPSILON) + if (std::abs(D) < FLOAT_EPSILON) { // segment is parallel to plane if (N == 0.0) |