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author | Tiger Wang <ziwei.tiger@hotmail.co.uk> | 2014-12-13 13:11:01 +0100 |
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committer | Tiger Wang <ziwei.tiger@hotmail.co.uk> | 2014-12-13 13:11:01 +0100 |
commit | 4b20a615192baeb5ef0a04a10161a03428cda8cd (patch) | |
tree | c6f25102267b0cc4a444f6e746679405948142b0 /src/Tracer.cpp | |
parent | Fixed compilation? (diff) | |
parent | Merge pull request #1660 from Seadragon91/master (diff) | |
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Diffstat (limited to 'src/Tracer.cpp')
-rw-r--r-- | src/Tracer.cpp | 120 |
1 files changed, 68 insertions, 52 deletions
diff --git a/src/Tracer.cpp b/src/Tracer.cpp index e125c6aa4..e604f4a5b 100644 --- a/src/Tracer.cpp +++ b/src/Tracer.cpp @@ -14,15 +14,15 @@ -cTracer::cTracer(cWorld * a_World) - : m_World(a_World) +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); + 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); } @@ -37,10 +37,16 @@ cTracer::~cTracer() -float cTracer::SigNum( float a_Num) +float cTracer::SigNum(float a_Num) { - if (a_Num < 0.f) return -1.f; - if (a_Num > 0.f) return 1.f; + if (a_Num < 0.f) + { + return -1.f; + } + if (a_Num > 0.f) + { + return 1.f; + } return 0.f; } @@ -59,7 +65,10 @@ void cTracer::SetValues(const Vector3f & a_Start, const Vector3f & a_Direction) step.z = (int) SigNum(dir.z); // normalize the direction vector - if (dir.SqrLength() > 0.f) dir.Normalize(); + if (dir.SqrLength() > 0.f) + { + dir.Normalize(); + } // how far we must move in the ray direction before // we encounter a new voxel in x-direction @@ -127,7 +136,7 @@ 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) +bool cTracer::Trace(const Vector3f & a_Start, const Vector3f & a_Direction, int a_Distance, bool a_LineOfSight) { if ((a_Start.y < 0) || (a_Start.y >= cChunkDef::Height)) { @@ -249,35 +258,42 @@ int LinesCross(float x0, float y0, float x1, float y1, float x2, float y2, float { // float linx, liny; - float d=(x1-x0)*(y3-y2)-(y1-y0)*(x3-x2); - if (std::abs(d)<0.001) {return 0;} - float AB=((y0-y2)*(x3-x2)-(x0-x2)*(y3-y2))/d; - if (AB>=0.0 && AB<=1.0) + float d = (x1 - x0) * (y3 - y2) - (y1 - y0) * (x3 - x2); + if (std::abs(d) < 0.001) { - float CD=((y0-y2)*(x1-x0)-(x0-x2)*(y1-y0))/d; - if (CD>=0.0 && CD<=1.0) + return 0; + } + + float AB = ((y0 - y2) * (x3 - x2) - (x0 - x2) * (y3 - y2)) / d; + if ((AB >= 0.0) && (AB <= 1.0)) + { + float CD = ((y0 - y2) * (x1 - x0) - (x0 - x2) * (y1 - y0)) / d; + if ((CD >= 0.0) && (CD <= 1.0)) { - // linx=x0+AB*(x1-x0); - // liny=y0+AB*(y1-y0); + // linx = x0 + AB * (x1 - x0); + // liny = y0 + AB * (y1 - y0); return 1; } } return 0; } + + + // intersect3D_SegmentPlane(): intersect a segment and a plane // Input: a_Ray = a segment, and a_Plane = a plane = {Point V0; Vector n;} // Output: *I0 = the intersect point (when it exists) // Return: 0 = disjoint (no intersection) // 1 = intersection in the unique point *I0 // 2 = the segment lies in the plane -int cTracer::intersect3D_SegmentPlane( const Vector3f & a_Origin, const Vector3f & a_End, const Vector3f & a_PlanePos, const Vector3f & a_PlaneNormal) +int cTracer::intersect3D_SegmentPlane(const Vector3f & a_Origin, const Vector3f & a_End, const Vector3f & a_PlanePos, const Vector3f & a_PlaneNormal) { Vector3f u = a_End - a_Origin; // a_Ray.P1 - S.P0; Vector3f w = a_Origin - a_PlanePos; // S.P0 - Pn.V0; - float D = a_PlaneNormal.Dot( u); // dot(Pn.n, u); - float N = -(a_PlaneNormal.Dot( w)); // -dot(a_Plane.n, w); + 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) @@ -294,12 +310,12 @@ int cTracer::intersect3D_SegmentPlane( const Vector3f & a_Origin, const Vector3f // they are not parallel // compute intersect param float sI = N / D; - if (sI < 0 || sI > 1) + if ((sI < 0) || (sI > 1)) { return 0; // no intersection } - // Vector3f I ( a_Ray->GetOrigin() + sI * u);// S.P0 + sI * u; // compute segment intersect point + // Vector3f I (a_Ray->GetOrigin() + sI * u);// S.P0 + sI * u; // compute segment intersect point RealHit = a_Origin + u * sI; return 1; } @@ -311,9 +327,9 @@ int cTracer::intersect3D_SegmentPlane( const Vector3f & a_Origin, const Vector3f int cTracer::GetHitNormal(const Vector3f & start, const Vector3f & end, const Vector3i & a_BlockPos) { Vector3i SmallBlockPos = a_BlockPos; - char BlockID = m_World->GetBlock( a_BlockPos.x, a_BlockPos.y, a_BlockPos.z); + char BlockID = m_World->GetBlock(a_BlockPos.x, a_BlockPos.y, a_BlockPos.z); - if (BlockID == E_BLOCK_AIR || IsBlockWater(BlockID)) + if ((BlockID == E_BLOCK_AIR) || IsBlockWater(BlockID)) { return 0; } @@ -324,86 +340,86 @@ int cTracer::GetHitNormal(const Vector3f & start, const Vector3f & end, const Ve Vector3f Look = (end - start); Look.Normalize(); - float dot = Look.Dot( Vector3f(-1, 0, 0)); // first face normal is x -1 + float dot = Look.Dot(Vector3f(-1, 0, 0)); // first face normal is x -1 if (dot < 0) { - int Lines = LinesCross( start.x, start.y, end.x, end.y, BlockPos.x, BlockPos.y, BlockPos.x, BlockPos.y + 1); + int Lines = LinesCross(start.x, start.y, end.x, end.y, BlockPos.x, BlockPos.y, BlockPos.x, BlockPos.y + 1); if (Lines == 1) { - Lines = LinesCross( start.x, start.z, end.x, end.z, BlockPos.x, BlockPos.z, BlockPos.x, BlockPos.z + 1); + Lines = LinesCross(start.x, start.z, end.x, end.z, BlockPos.x, BlockPos.z, BlockPos.x, BlockPos.z + 1); if (Lines == 1) { - intersect3D_SegmentPlane( start, end, BlockPos, Vector3f(-1, 0, 0)); + intersect3D_SegmentPlane(start, end, BlockPos, Vector3f(-1, 0, 0)); return 1; } } } - dot = Look.Dot( Vector3f(0, 0, -1)); // second face normal is z -1 + dot = Look.Dot(Vector3f(0, 0, -1)); // second face normal is z -1 if (dot < 0) { - int Lines = LinesCross( start.z, start.y, end.z, end.y, BlockPos.z, BlockPos.y, BlockPos.z, BlockPos.y + 1); + int Lines = LinesCross(start.z, start.y, end.z, end.y, BlockPos.z, BlockPos.y, BlockPos.z, BlockPos.y + 1); if (Lines == 1) { - Lines = LinesCross( start.z, start.x, end.z, end.x, BlockPos.z, BlockPos.x, BlockPos.z, BlockPos.x + 1); + Lines = LinesCross(start.z, start.x, end.z, end.x, BlockPos.z, BlockPos.x, BlockPos.z, BlockPos.x + 1); if (Lines == 1) { - intersect3D_SegmentPlane( start, end, BlockPos, Vector3f(0, 0, -1)); + intersect3D_SegmentPlane(start, end, BlockPos, Vector3f(0, 0, -1)); return 2; } } } - dot = Look.Dot( Vector3f(1, 0, 0)); // third face normal is x 1 + dot = Look.Dot(Vector3f(1, 0, 0)); // third face normal is x 1 if (dot < 0) { - int Lines = LinesCross( start.x, start.y, end.x, end.y, BlockPos.x + 1, BlockPos.y, BlockPos.x + 1, BlockPos.y + 1); + int Lines = LinesCross(start.x, start.y, end.x, end.y, BlockPos.x + 1, BlockPos.y, BlockPos.x + 1, BlockPos.y + 1); if (Lines == 1) { - Lines = LinesCross( start.x, start.z, end.x, end.z, BlockPos.x + 1, BlockPos.z, BlockPos.x + 1, BlockPos.z + 1); + Lines = LinesCross(start.x, start.z, end.x, end.z, BlockPos.x + 1, BlockPos.z, BlockPos.x + 1, BlockPos.z + 1); if (Lines == 1) { - intersect3D_SegmentPlane( start, end, BlockPos + Vector3f(1, 0, 0), Vector3f(1, 0, 0)); + intersect3D_SegmentPlane(start, end, BlockPos + Vector3f(1, 0, 0), Vector3f(1, 0, 0)); return 3; } } } - dot = Look.Dot( Vector3f(0, 0, 1)); // fourth face normal is z 1 + dot = Look.Dot(Vector3f(0, 0, 1)); // fourth face normal is z 1 if (dot < 0) { - int Lines = LinesCross( start.z, start.y, end.z, end.y, BlockPos.z + 1, BlockPos.y, BlockPos.z + 1, BlockPos.y + 1); + int Lines = LinesCross(start.z, start.y, end.z, end.y, BlockPos.z + 1, BlockPos.y, BlockPos.z + 1, BlockPos.y + 1); if (Lines == 1) { - Lines = LinesCross( start.z, start.x, end.z, end.x, BlockPos.z + 1, BlockPos.x, BlockPos.z + 1, BlockPos.x + 1); + Lines = LinesCross(start.z, start.x, end.z, end.x, BlockPos.z + 1, BlockPos.x, BlockPos.z + 1, BlockPos.x + 1); if (Lines == 1) { - intersect3D_SegmentPlane( start, end, BlockPos + Vector3f(0, 0, 1), Vector3f(0, 0, 1)); + intersect3D_SegmentPlane(start, end, BlockPos + Vector3f(0, 0, 1), Vector3f(0, 0, 1)); return 4; } } } - dot = Look.Dot( Vector3f(0, 1, 0)); // fifth face normal is y 1 + dot = Look.Dot(Vector3f(0, 1, 0)); // fifth face normal is y 1 if (dot < 0) { - int Lines = LinesCross( start.y, start.x, end.y, end.x, BlockPos.y + 1, BlockPos.x, BlockPos.y + 1, BlockPos.x + 1); + int Lines = LinesCross(start.y, start.x, end.y, end.x, BlockPos.y + 1, BlockPos.x, BlockPos.y + 1, BlockPos.x + 1); if (Lines == 1) { - Lines = LinesCross( start.y, start.z, end.y, end.z, BlockPos.y + 1, BlockPos.z, BlockPos.y + 1, BlockPos.z + 1); + Lines = LinesCross(start.y, start.z, end.y, end.z, BlockPos.y + 1, BlockPos.z, BlockPos.y + 1, BlockPos.z + 1); if (Lines == 1) { - intersect3D_SegmentPlane( start, end, BlockPos + Vector3f(0, 1, 0), Vector3f(0, 1, 0)); + intersect3D_SegmentPlane(start, end, BlockPos + Vector3f(0, 1, 0), Vector3f(0, 1, 0)); return 5; } } } - dot = Look.Dot( Vector3f(0, -1, 0)); // sixth face normal is y -1 + dot = Look.Dot(Vector3f(0, -1, 0)); // sixth face normal is y -1 if (dot < 0) { - int Lines = LinesCross( start.y, start.x, end.y, end.x, BlockPos.y, BlockPos.x, BlockPos.y, BlockPos.x + 1); + int Lines = LinesCross(start.y, start.x, end.y, end.x, BlockPos.y, BlockPos.x, BlockPos.y, BlockPos.x + 1); if (Lines == 1) { - Lines = LinesCross( start.y, start.z, end.y, end.z, BlockPos.y, BlockPos.z, BlockPos.y, BlockPos.z + 1); + Lines = LinesCross(start.y, start.z, end.y, end.z, BlockPos.y, BlockPos.z, BlockPos.y, BlockPos.z + 1); if (Lines == 1) { - intersect3D_SegmentPlane( start, end, BlockPos, Vector3f(0, -1, 0)); + intersect3D_SegmentPlane(start, end, BlockPos, Vector3f(0, -1, 0)); return 6; } } |