Initial work on unclassing raycast.

2012-10-02 16:03:39 +02:00
parent ca66396631
commit 23184e6924
3 changed files with 130 additions and 3 deletions
--- a/library/PolyVoxCore/include/PolyVoxCore/Raycast.h
+++ b/library/PolyVoxCore/include/PolyVoxCore/Raycast.h
@ -120,6 +120,90 @@ namespace PolyVox
 		Vector3DFloat m_v3dDirectionAndLength;
 		float m_fMaxDistance;
 	};
+
+	template<typename VolumeType, typename Callback>
+	void raycast(VolumeType* volData, /*const*/ Vector3DFloat/*&*/ v3dStart, const Vector3DFloat& v3dDirectionAndLength, Callback& callback)
+	{
+		VolumeType::Sampler sampler(volData);
+
+		//The doRaycast function is assuming that it is iterating over the areas defined between
+		//voxels. We actually want to define the areas as being centered on voxels (as this is
+		//what the CubicSurfaceExtractor generates). We add (0.5,0.5,0.5) here to adjust for this.
+		v3dStart = v3dStart + Vector3DFloat(0.5f, 0.5f, 0.5f);
+
+		//Compute the end point
+		Vector3DFloat v3dEnd = v3dStart + v3dDirectionAndLength;
+
+		float x1 = v3dStart.getX();
+		float y1 = v3dStart.getY();
+		float z1 = v3dStart.getZ();
+		float x2 = v3dEnd.getX();
+		float y2 = v3dEnd.getY();
+		float z2 = v3dEnd.getZ();
+		
+		int i = (int)floorf(x1);
+		int j = (int)floorf(y1);
+		int k = (int)floorf(z1);
+
+		int iend = (int)floorf(x2);
+		int jend = (int)floorf(y2);
+		int kend = (int)floorf(z2);
+
+		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 deltatx = 1.0f / std::abs(x2 - x1);
+		float deltaty = 1.0f / std::abs(y2 - y1);
+		float deltatz = 1.0f / std::abs(z2 - z1);
+
+		float minx = floorf(x1), maxx = minx + 1.0f;
+		float tx = ((x1 > x2) ? (x1 - minx) : (maxx - x1)) * deltatx;
+		float miny = floorf(y1), maxy = miny + 1.0f;
+		float ty = ((y1 > y2) ? (y1 - miny) : (maxy - y1)) * deltaty;
+		float minz = floorf(z1), maxz = minz + 1.0f;
+		float tz = ((z1 > z2) ? (z1 - minz) : (maxz - z1)) * deltatz;
+
+		sampler.setPosition(i,j,k);
+		//m_result.previousVoxel = Vector3DInt32(i,j,k);
+
+		for(;;)
+		{
+			if(!callback(sampler))
+			{
+				//m_result.foundIntersection = true;
+				//m_result.intersectionVoxel = Vector3DInt32(i,j,k);
+				return;
+			}
+			//m_result.previousVoxel = Vector3DInt32(i,j,k);
+
+			if(tx <= ty && tx <= tz)
+			{
+				if(i == iend) break;
+				tx += deltatx;
+				i += di;
+
+				if(di == 1) sampler.movePositiveX();
+				if(di == -1) sampler.moveNegativeX();
+			} else if (ty <= tz)
+			{
+				if(j == jend) break;
+				ty += deltaty;
+				j += dj;
+
+				if(dj == 1) sampler.movePositiveY();
+				if(dj == -1) sampler.moveNegativeY();
+			} else 
+			{
+				if(k == kend) break;
+				tz += deltatz;
+				k += dk;
+
+				if(dk == 1) sampler.movePositiveZ();
+				if(dk == -1) sampler.moveNegativeZ();
+			}
+		}
+	}
 }

 #include "PolyVoxCore/Raycast.inl"