87 lines
4.1 KiB
C++
87 lines
4.1 KiB
C++
/*******************************************************************************
|
|
* The MIT License (MIT)
|
|
*
|
|
* Copyright (c) 2015 David Williams and Matthew Williams
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in all
|
|
* copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
* SOFTWARE.
|
|
*******************************************************************************/
|
|
|
|
#ifndef __PolyVox_Raycast_H__
|
|
#define __PolyVox_Raycast_H__
|
|
|
|
#include "Vector.h"
|
|
|
|
namespace PolyVox
|
|
{
|
|
namespace RaycastResults
|
|
{
|
|
/**
|
|
* The results of a raycast
|
|
*/
|
|
enum RaycastResult
|
|
{
|
|
Completed, ///< If the ray passed through the volume without being interupted
|
|
Interupted ///< If the ray was interupted while travelling
|
|
};
|
|
}
|
|
typedef RaycastResults::RaycastResult RaycastResult;
|
|
|
|
/// OUT OF DATE SINCE UNCLASSING
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
/// \file Raycast.h
|
|
///
|
|
/// The principle behind raycasting is to fire a 'ray' through the volume and determine
|
|
/// what (if anything) that ray hits. This simple test can be used for the purpose of
|
|
/// picking, visibility checks, lighting calculations, or numerous other applications.
|
|
///
|
|
/// A ray is a stright line in space define by a start point and a direction vector.
|
|
/// The length of the direction vector represents the length of the ray. When you
|
|
/// execute a raycast it will iterate over each voxel which lies on the ray,
|
|
/// starting from the defined start point. It will examine each voxel and terminate
|
|
/// either when it encounters a solid voxel or when it reaches the end of the ray.
|
|
///
|
|
/// **Important Note:** These has been confusion in the past with people not realising
|
|
/// that the length of the direction vector is important. Most graphics API can provide
|
|
/// a camera position and view direction for picking purposes, but the view direction is
|
|
/// usually normalised (i.e. of length one). If you use this view direction directly you
|
|
/// will only iterate over a single voxel and won't find what you are looking for. Instead
|
|
/// you must scale the direction vector so that it's length represents the maximum distance
|
|
/// over which you want the ray to be cast.
|
|
///
|
|
/// Some further notes, the Raycast uses full 26-connectivity, which basically means it
|
|
/// will examine every voxel the ray touches, even if it just passes through the corner.
|
|
/// Also, it peforms a simple binary test against a voxel's threshold, rather than making
|
|
/// use of it's density. Therefore it will work best in conjunction with one of the 'cubic'
|
|
/// surace extractors. It's behaviour with the Marching Cubes surface extractor has not
|
|
/// been tested yet.
|
|
///
|
|
/// Note that we also have a pickVoxel() function which provides a slightly higher-level interface.
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
template<typename VolumeType, typename Callback>
|
|
RaycastResult raycastWithEndpoints(VolumeType* volData, const Vector3DFloat& v3dStart, const Vector3DFloat& v3dEnd, Callback& callback);
|
|
|
|
template<typename VolumeType, typename Callback>
|
|
RaycastResult raycastWithDirection(VolumeType* volData, const Vector3DFloat& v3dStart, const Vector3DFloat& v3dDirectionAndLength, Callback& callback);
|
|
}
|
|
|
|
#include "Raycast.inl"
|
|
|
|
#endif //__PolyVox_Raycast_H__
|