97 lines
3.2 KiB
C++
97 lines
3.2 KiB
C++
/*******************************************************************************
|
|
Copyright (c) 2005-2009 David Williams
|
|
|
|
This software is provided 'as-is', without any express or implied
|
|
warranty. In no event will the authors be held liable for any damages
|
|
arising from the use of this software.
|
|
|
|
Permission is granted to anyone to use this software for any purpose,
|
|
including commercial applications, and to alter it and redistribute it
|
|
freely, subject to the following restrictions:
|
|
|
|
1. The origin of this software must not be misrepresented; you must not
|
|
claim that you wrote the original software. If you use this software
|
|
in a product, an acknowledgment in the product documentation would be
|
|
appreciated but is not required.
|
|
|
|
2. Altered source versions must be plainly marked as such, and must not be
|
|
misrepresented as being the original software.
|
|
|
|
3. This notice may not be removed or altered from any source
|
|
distribution.
|
|
*******************************************************************************/
|
|
namespace PolyVox
|
|
{
|
|
template <typename VoxelType>
|
|
Raycast<VoxelType>::Raycast(Volume<VoxelType>* volData, const Vector3DFloat& v3dStart, const Vector3DFloat& v3dDirection, float fMaxDistance)
|
|
:m_volData(volData)
|
|
,m_v3dStart(v3dStart)
|
|
,m_v3dDirection(v3dDirection)
|
|
,m_fMaxDistance(fMaxDistance)
|
|
{
|
|
}
|
|
|
|
template <typename VoxelType>
|
|
void Raycast<VoxelType>::execute(void)
|
|
{
|
|
Vector3DFloat v3dEnd = m_v3dStart + m_v3dDirection;
|
|
hit = doRaycast(m_v3dStart.getX(), m_v3dStart.getY(), m_v3dStart.getZ(), v3dEnd.getX(), v3dEnd.getY(), v3dEnd.getZ());
|
|
}
|
|
|
|
template <typename VoxelType>
|
|
bool Raycast<VoxelType>::doRaycast(float x1, float y1, float z1, float x2, float y2, float z2)
|
|
{
|
|
const float CELL_SIDE = 1.0f;
|
|
|
|
int i = (int)floorf(x1 / CELL_SIDE);
|
|
int j = (int)floorf(y1 / CELL_SIDE);
|
|
int k = (int)floorf(z1 / CELL_SIDE);
|
|
|
|
int iend = (int)floorf(x2 / CELL_SIDE);
|
|
int jend = (int)floorf(y2 / CELL_SIDE);
|
|
int kend = (int)floorf(z2 / CELL_SIDE);
|
|
|
|
int di = ((x1 < x2) ? 1 : ((x1 > x2) ? -1 : 0));
|
|
int dj = ((y1 < y2) ? 1 : ((y1 > y2) ? -1 : 0));
|
|
int dk = ((z1 < z2) ? 1 : ((z1 > z2) ? -1 : 0));
|
|
|
|
float minx = CELL_SIDE * floorf(x1/CELL_SIDE), maxx = minx + CELL_SIDE;
|
|
float tx = ((x1 > x2) ? (x1 - minx) : (maxx - x1)) / abs(x2 - x1);
|
|
float miny = CELL_SIDE * floorf(y1/CELL_SIDE), maxy = miny + CELL_SIDE;
|
|
float ty = ((y1 > y2) ? (y1 - miny) : (maxy - y1)) / abs(y2 - y1);
|
|
float minz = CELL_SIDE * floorf(z1/CELL_SIDE), maxz = minz + CELL_SIDE;
|
|
float tz = ((z1 > z2) ? (z1 - minz) : (maxz - z1)) / abs(z2 - z1);
|
|
|
|
float deltatx = CELL_SIDE / abs(x2 - x1);
|
|
float deltaty = CELL_SIDE / abs(y2 - y1);
|
|
float deltatz = CELL_SIDE / abs(z2 - z1);
|
|
|
|
for(;;)
|
|
{
|
|
//cout << i << ", " << j << ", " << k << endl;
|
|
if(m_volData->getVoxelAt(i,j,k).getDensity() > VoxelType::getThreshold())
|
|
{
|
|
x = i;
|
|
y = j;
|
|
z = k;
|
|
return true;
|
|
}
|
|
|
|
if(tx <= ty && tx <= tz) {
|
|
if(i == iend) break;
|
|
tx += deltatx;
|
|
i += di;
|
|
} else if (ty <= tz){
|
|
if(j == jend) break;
|
|
ty += deltaty;
|
|
j += dj;
|
|
} else {
|
|
if(k == kend) break;
|
|
tz += deltatz;
|
|
k += dk;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
} |