minetest/src/raycast.cpp
Dániel Juhász 3f8261830e Improve getPointedThing() (#4346)
* Improved getPointedThing()

The new algorithm checks every node exactly once.
Now the point and normal vector of the collision is also returned in the
PointedThing (currently they are not used outside of the function).
Now the CNodeDefManager keeps the union of all possible nodeboxes, so
the raycast won't miss any nodes. Also if there are only small
nodeboxes, getPointedThing() is exceptionally fast.
Also adds unit test for VoxelLineIterator.

* Cleanup, code move

This commit moves getPointedThing() and
Client::getSelectedActiveObject() to ClientEnvironment.
The map nodes now can decide which neighbors they are connecting to
(MapNode::getNeighbors()).
2017-01-04 19:18:40 +01:00

90 lines
2.5 KiB
C++

/*
Minetest
Copyright (C) 2016 juhdanad, Daniel Juhasz <juhdanad@gmail.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "irr_v3d.h"
#include "irr_aabb3d.h"
bool boxLineCollision(const aabb3f &box, const v3f &start,
const v3f &dir, v3f *collision_point, v3s16 *collision_normal) {
if (box.isPointInside(start)) {
*collision_point = start;
collision_normal->set(0, 0, 0);
return true;
}
float m = 0;
// Test X collision
if (dir.X != 0) {
if (dir.X > 0)
m = (box.MinEdge.X - start.X) / dir.X;
else
m = (box.MaxEdge.X - start.X) / dir.X;
if (m >= 0 && m <= 1) {
*collision_point = start + dir * m;
if ((collision_point->Y >= box.MinEdge.Y)
&& (collision_point->Y <= box.MaxEdge.Y)
&& (collision_point->Z >= box.MinEdge.Z)
&& (collision_point->Z <= box.MaxEdge.Z)) {
collision_normal->set((dir.X > 0) ? -1 : 1, 0, 0);
return true;
}
}
}
// Test Y collision
if (dir.Y != 0) {
if (dir.Y > 0)
m = (box.MinEdge.Y - start.Y) / dir.Y;
else
m = (box.MaxEdge.Y - start.Y) / dir.Y;
if (m >= 0 && m <= 1) {
*collision_point = start + dir * m;
if ((collision_point->X >= box.MinEdge.X)
&& (collision_point->X <= box.MaxEdge.X)
&& (collision_point->Z >= box.MinEdge.Z)
&& (collision_point->Z <= box.MaxEdge.Z)) {
collision_normal->set(0, (dir.Y > 0) ? -1 : 1, 0);
return true;
}
}
}
// Test Z collision
if (dir.Z != 0) {
if (dir.Z > 0)
m = (box.MinEdge.Z - start.Z) / dir.Z;
else
m = (box.MaxEdge.Z - start.Z) / dir.Z;
if (m >= 0 && m <= 1) {
*collision_point = start + dir * m;
if ((collision_point->X >= box.MinEdge.X)
&& (collision_point->X <= box.MaxEdge.X)
&& (collision_point->Y >= box.MinEdge.Y)
&& (collision_point->Y <= box.MaxEdge.Y)) {
collision_normal->set(0, 0, (dir.Z > 0) ? -1 : 1);
return true;
}
}
}
return false;
}