diff options
Diffstat (limited to 'source/cTracer.cpp')
-rw-r--r-- | source/cTracer.cpp | 700 |
1 files changed, 350 insertions, 350 deletions
diff --git a/source/cTracer.cpp b/source/cTracer.cpp index 5cfc41b60..fba0f908c 100644 --- a/source/cTracer.cpp +++ b/source/cTracer.cpp @@ -1,350 +1,350 @@ -
-#include "Globals.h" // NOTE: MSVC stupidness requires this to be the same across all modules
-
-#include "cTracer.h"
-#include "cWorld.h"
-
-#include "Vector3f.h"
-#include "Vector3i.h"
-#include "Vector3d.h"
-
-#include "BlockID.h"
-#include "cEntity.h"
-
-#include "Defines.h"
-
-#ifndef _WIN32
- #include <stdlib.h> // abs()
-#endif
-
-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);
-}
-
-cTracer::~cTracer()
-{
-}
-
-float cTracer::SigNum( float a_Num )
-{
- if (a_Num < 0.f) return -1.f;
- if (a_Num > 0.f) return 1.f;
- return 0.f;
-}
-
-void cTracer::SetValues( const Vector3f & a_Start, const Vector3f & a_Direction )
-{
- // 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);
-
- // normalize the direction vector
- 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
- // same but y-direction
- if( dir.x != 0.f ) tDelta.x = 1/fabs(dir.x);
- else tDelta.x = 0;
- if( dir.y != 0.f ) tDelta.y = 1/fabs(dir.y);
- else tDelta.y = 0;
- if( dir.z != 0.f ) tDelta.z = 1/fabs(dir.z);
- else tDelta.z = 0;
-
- // start voxel coordinates
- // use your
- // transformer
- // function here
- pos.x = (int)floorf(a_Start.x);
- pos.y = (int)floorf(a_Start.y);
- pos.z = (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;
- }
- else
- {
- tMax.x = (((float)pos.x + 1) - a_Start.x) / dir.x;
- }
-
- if(dir.y < 0)
- {
- tMax.y = ((float)pos.y - a_Start.y) / dir.y;
- }
- else
- {
- tMax.y = (((float)pos.y + 1) - a_Start.y) / dir.y;
- }
-
- if(dir.z < 0)
- {
- tMax.z = ((float)pos.z - a_Start.z) / dir.z;
- }
- else
- {
- tMax.z = (((float)pos.z + 1) - a_Start.z) / dir.z;
- }
-}
-
-int cTracer::Trace( const Vector3f & a_Start, const Vector3f & a_Direction, int a_Distance)
-{
- SetValues( a_Start, a_Direction );
-
- const Vector3f End = a_Start + (dir * (float)a_Distance);
-
- // end voxel coordinates
- end1.x = (int)floorf(End.x);
- end1.y = (int)floorf(End.y);
- end1.z = (int)floorf(End.z);
-
- // check if first is occupied
- if( pos.Equals( end1 ) )
- {
- LOG("WARNING: cTracer: Start and end in same block");
- return 0;
- }
-
- bool reachedX = false, reachedY = false, reachedZ = false;
-
- int Iterations = 0;
- while ( Iterations < a_Distance )
- {
- Iterations++;
- if(tMax.x < tMax.y && tMax.x < tMax.z)
- {
- tMax.x += tDelta.x;
- pos.x += step.x;
- }
- else if(tMax.y < tMax.z)
- {
- tMax.y += tDelta.y;
- pos.y += step.y;
- }
- else
- {
- tMax.z += tDelta.z;
- pos.z += step.z;
- }
-
- if(step.x > 0.0f)
- {
- if(pos.x >= end1.x)
- {
- reachedX = true;
- }
- }
- else if(pos.x <= end1.x)
- {
- reachedX = true;
- }
-
- if(step.y > 0.0f)
- {
- if(pos.y >= end1.y)
- {
- reachedY = true;
- }
- }
- else if(pos.y <= end1.y)
- {
- reachedY = true;
- }
-
- if(step.z > 0.0f)
- {
- if(pos.z >= end1.z)
- {
- reachedZ = true;
- }
- }
- else if(pos.z <= end1.z)
- {
- reachedZ = true;
- }
-
- if (reachedX && reachedY && reachedZ)
- {
- return false;
- }
-
- char BlockID = m_World->GetBlock( pos.x, pos.y, pos.z );
- //No collision with water ;)
- if ( BlockID != E_BLOCK_AIR || IsBlockWater(BlockID))
- {
- BlockHitPosition = pos;
- int Normal = GetHitNormal(a_Start, End, pos );
- if(Normal > 0)
- {
- HitNormal = m_NormalTable[Normal-1];
- }
- return 1;
- }
- }
- return 0;
-}
-
-// return 1 = hit, other is not hit
-int LinesCross(float x0,float y0,float x1,float y1,float x2,float y2,float x3,float y3)
-{
- //float linx, liny;
-
- float d=(x1-x0)*(y3-y2)-(y1-y0)*(x3-x2);
- if (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 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);
- 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 )
-{
- 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);
-
- const float EPSILON = 0.0001f;
- if (fabs(D) < EPSILON) { // segment is parallel to plane
- if (N == 0) // segment lies in plane
- return 2;
- return 0; // no intersection
- }
- // they are not parallel
- // compute intersect param
- float sI = N / D;
- if (sI < 0 || sI > 1)
- return 0; // no intersection
-
- //Vector3f I ( a_Ray->GetOrigin() + sI * u );//S.P0 + sI * u; // compute segment intersect point
- RealHit = a_Origin + u * sI;
- return 1;
-}
-
-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 );
-
- if( BlockID == E_BLOCK_AIR || IsBlockWater(BlockID))
- return 0;
-
- Vector3f BlockPos;
- BlockPos = Vector3f(SmallBlockPos);
-
- Vector3f Look = (end - start);
- Look.Normalize();
-
- 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 );
- if(Lines == 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) );
- return 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 );
- if(Lines == 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) );
- return 2;
- }
- }
- }
- 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 );
- if(Lines == 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) );
- return 3;
- }
- }
- }
- 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 );
- if(Lines == 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) );
- return 4;
- }
- }
- }
- 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 );
- if(Lines == 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) );
- return 5;
- }
- }
- }
- 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 );
- if(Lines == 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) );
- return 6;
- }
- }
- }
- return 0;
-}
+ +#include "Globals.h" // NOTE: MSVC stupidness requires this to be the same across all modules + +#include "cTracer.h" +#include "cWorld.h" + +#include "Vector3f.h" +#include "Vector3i.h" +#include "Vector3d.h" + +#include "BlockID.h" +#include "cEntity.h" + +#include "Defines.h" + +#ifndef _WIN32 + #include <stdlib.h> // abs() +#endif + +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); +} + +cTracer::~cTracer() +{ +} + +float cTracer::SigNum( float a_Num ) +{ + if (a_Num < 0.f) return -1.f; + if (a_Num > 0.f) return 1.f; + return 0.f; +} + +void cTracer::SetValues( const Vector3f & a_Start, const Vector3f & a_Direction ) +{ + // 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); + + // normalize the direction vector + 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 + // same but y-direction + if( dir.x != 0.f ) tDelta.x = 1/fabs(dir.x); + else tDelta.x = 0; + if( dir.y != 0.f ) tDelta.y = 1/fabs(dir.y); + else tDelta.y = 0; + if( dir.z != 0.f ) tDelta.z = 1/fabs(dir.z); + else tDelta.z = 0; + + // start voxel coordinates + // use your + // transformer + // function here + pos.x = (int)floorf(a_Start.x); + pos.y = (int)floorf(a_Start.y); + pos.z = (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; + } + else + { + tMax.x = (((float)pos.x + 1) - a_Start.x) / dir.x; + } + + if(dir.y < 0) + { + tMax.y = ((float)pos.y - a_Start.y) / dir.y; + } + else + { + tMax.y = (((float)pos.y + 1) - a_Start.y) / dir.y; + } + + if(dir.z < 0) + { + tMax.z = ((float)pos.z - a_Start.z) / dir.z; + } + else + { + tMax.z = (((float)pos.z + 1) - a_Start.z) / dir.z; + } +} + +int cTracer::Trace( const Vector3f & a_Start, const Vector3f & a_Direction, int a_Distance) +{ + SetValues( a_Start, a_Direction ); + + const Vector3f End = a_Start + (dir * (float)a_Distance); + + // end voxel coordinates + end1.x = (int)floorf(End.x); + end1.y = (int)floorf(End.y); + end1.z = (int)floorf(End.z); + + // check if first is occupied + if( pos.Equals( end1 ) ) + { + LOG("WARNING: cTracer: Start and end in same block"); + return 0; + } + + bool reachedX = false, reachedY = false, reachedZ = false; + + int Iterations = 0; + while ( Iterations < a_Distance ) + { + Iterations++; + if(tMax.x < tMax.y && tMax.x < tMax.z) + { + tMax.x += tDelta.x; + pos.x += step.x; + } + else if(tMax.y < tMax.z) + { + tMax.y += tDelta.y; + pos.y += step.y; + } + else + { + tMax.z += tDelta.z; + pos.z += step.z; + } + + if(step.x > 0.0f) + { + if(pos.x >= end1.x) + { + reachedX = true; + } + } + else if(pos.x <= end1.x) + { + reachedX = true; + } + + if(step.y > 0.0f) + { + if(pos.y >= end1.y) + { + reachedY = true; + } + } + else if(pos.y <= end1.y) + { + reachedY = true; + } + + if(step.z > 0.0f) + { + if(pos.z >= end1.z) + { + reachedZ = true; + } + } + else if(pos.z <= end1.z) + { + reachedZ = true; + } + + if (reachedX && reachedY && reachedZ) + { + return false; + } + + char BlockID = m_World->GetBlock( pos.x, pos.y, pos.z ); + //No collision with water ;) + if ( BlockID != E_BLOCK_AIR || IsBlockWater(BlockID)) + { + BlockHitPosition = pos; + int Normal = GetHitNormal(a_Start, End, pos ); + if(Normal > 0) + { + HitNormal = m_NormalTable[Normal-1]; + } + return 1; + } + } + return 0; +} + +// return 1 = hit, other is not hit +int LinesCross(float x0,float y0,float x1,float y1,float x2,float y2,float x3,float y3) +{ + //float linx, liny; + + float d=(x1-x0)*(y3-y2)-(y1-y0)*(x3-x2); + if (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 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); + 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 ) +{ + 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); + + const float EPSILON = 0.0001f; + if (fabs(D) < EPSILON) { // segment is parallel to plane + if (N == 0) // segment lies in plane + return 2; + return 0; // no intersection + } + // they are not parallel + // compute intersect param + float sI = N / D; + if (sI < 0 || sI > 1) + return 0; // no intersection + + //Vector3f I ( a_Ray->GetOrigin() + sI * u );//S.P0 + sI * u; // compute segment intersect point + RealHit = a_Origin + u * sI; + return 1; +} + +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 ); + + if( BlockID == E_BLOCK_AIR || IsBlockWater(BlockID)) + return 0; + + Vector3f BlockPos; + BlockPos = Vector3f(SmallBlockPos); + + Vector3f Look = (end - start); + Look.Normalize(); + + 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 ); + if(Lines == 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) ); + return 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 ); + if(Lines == 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) ); + return 2; + } + } + } + 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 ); + if(Lines == 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) ); + return 3; + } + } + } + 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 ); + if(Lines == 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) ); + return 4; + } + } + } + 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 ); + if(Lines == 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) ); + return 5; + } + } + } + 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 ); + if(Lines == 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) ); + return 6; + } + } + } + return 0; +} |