src/raycast.h

   1 /*
   2 Minetest
   3 Copyright (C) 2016 juhdanad, Daniel Juhasz <juhdanad@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #pragma once
  21
  22 #include "voxelalgorithms.h"
  23 #include "util/pointedthing.h"
  24
  25 //! Sorts PointedThings based on their distance.
  26 struct RaycastSort
  27 {
  28         bool operator() (const PointedThing &pt1, const PointedThing &pt2) const;
  29 };
  30
  31 //! Describes the state of a raycast.
  32 class RaycastState
  33 {
  34 public:
  35         /*!
  36          * Creates a raycast.
  37          * @param objects_pointable if false, only nodes will be found
  38          * @param liquids pointable if false, liquid nodes won't be found
  39          */
  40         RaycastState(const core::line3d<f32> &shootline, bool objects_pointable,
  41                 bool liquids_pointable, bool nodes_pointable = true);
  42
  43         //! Shootline of the raycast.
  44         core::line3d<f32> m_shootline;
  45         //! Iterator to store the progress of the raycast.
  46         voxalgo::VoxelLineIterator m_iterator;
  47         //! Previous tested node during the raycast.
  48         v3s16 m_previous_node;
  49
  50         /*!
  51          * This priority queue stores the found pointed things
  52          * waiting to be returned.
  53          */
  54         std::priority_queue<PointedThing, std::vector<PointedThing>, RaycastSort> m_found;
  55
  56         bool m_objects_pointable;
  57         bool m_liquids_pointable;
  58         bool m_nodes_pointable;
  59
  60         //! The code needs to search these nodes around the center node.
  61         core::aabbox3d<s16> m_search_range { 0, 0, 0, 0, 0, 0 };
  62
  63         //! If true, the Environment will initialize this state.
  64         bool m_initialization_needed = true;
  65 };
  66
  67 /*!
  68  * Checks if a line and a box intersects.
  69  * @param[in]  box              box to test collision
  70  * @param[in]  start            starting point of the line
  71  * @param[in]  dir              direction and length of the line
  72  * @param[out] collision_point  first point of the collision
  73  * @param[out] collision_normal normal vector at the collision, points
  74  * outwards of the surface. If start is in the box, zero vector.
  75  * @returns true if a collision point was found
  76  */
  77 bool boxLineCollision(const aabb3f &box, const v3f &start, const v3f &dir,
  78         v3f *collision_point, v3s16 *collision_normal);