3 Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
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.
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.
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.
23 #include "constants.h" // BS, MAP_BLOCKSIZE
24 #include "noise.h" // PseudoRandom, PcgRandom
25 #include "threading/mutex_auto_lock.h"
36 return g_pcgrand.next();
39 void mysrand(unsigned int seed)
44 void myrand_bytes(void *out, size_t len)
46 g_pcgrand.bytes(out, len);
49 int myrand_range(int min, int max)
51 return g_pcgrand.range(min, max);
56 64-bit unaligned version of MurmurHash
58 u64 murmur_hash_64_ua(const void *key, int len, unsigned int seed)
60 const u64 m = 0xc6a4a7935bd1e995ULL;
62 u64 h = seed ^ (len * m);
64 const u8 *data = (const u8 *)key;
65 const u8 *end = data + (len / 8) * 8;
69 memcpy(&k, data, sizeof(u64));
80 const unsigned char *data2 = (const unsigned char *)data;
82 case 7: h ^= (u64)data2[6] << 48;
83 case 6: h ^= (u64)data2[5] << 40;
84 case 5: h ^= (u64)data2[4] << 32;
85 case 4: h ^= (u64)data2[3] << 24;
86 case 3: h ^= (u64)data2[2] << 16;
87 case 2: h ^= (u64)data2[1] << 8;
88 case 1: h ^= (u64)data2[0];
100 blockpos_b: position of block in block coordinates
101 camera_pos: position of camera in nodes
102 camera_dir: an unit vector pointing to camera direction
104 distance_ptr: return location for distance from the camera
106 bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
107 f32 camera_fov, f32 range, f32 *distance_ptr)
109 v3s16 blockpos_nodes = blockpos_b * MAP_BLOCKSIZE;
111 // Block center position
113 ((float)blockpos_nodes.X + MAP_BLOCKSIZE/2) * BS,
114 ((float)blockpos_nodes.Y + MAP_BLOCKSIZE/2) * BS,
115 ((float)blockpos_nodes.Z + MAP_BLOCKSIZE/2) * BS
118 // Block position relative to camera
119 v3f blockpos_relative = blockpos - camera_pos;
122 f32 d = MYMAX(0, blockpos_relative.getLength() - BLOCK_MAX_RADIUS);
127 // If block is far away, it's not in sight
131 // If block is (nearly) touching the camera, don't
132 // bother validating further (that is, render it anyway)
136 // Adjust camera position, for purposes of computing the angle,
137 // such that a block that has any portion visible with the
138 // current camera position will have the center visible at the
140 f32 adjdist = BLOCK_MAX_RADIUS / cos((M_PI - camera_fov) / 2);
142 // Block position relative to adjusted camera
143 v3f blockpos_adj = blockpos - (camera_pos - camera_dir * adjdist);
145 // Distance in camera direction (+=front, -=back)
146 f32 dforward = blockpos_adj.dotProduct(camera_dir);
148 // Cosine of the angle between the camera direction
149 // and the block direction (camera_dir is an unit vector)
150 f32 cosangle = dforward / blockpos_adj.getLength();
152 // If block is not in the field of view, skip it
153 // HOTFIX: use sligthly increased angle (+10%) to fix too agressive
154 // culling. Somebody have to find out whats wrong with the math here.
155 // Previous value: camera_fov / 2
156 if (cosangle < std::cos(camera_fov * 0.55f))
162 s16 adjustDist(s16 dist, float zoom_fov)
164 // 1.775 ~= 72 * PI / 180 * 1.4, the default FOV on the client.
165 // The heuristic threshold for zooming is half of that.
166 static constexpr const float threshold_fov = 1.775f / 2.0f;
167 if (zoom_fov < 0.001f || zoom_fov > threshold_fov)
170 return std::round(dist * std::cbrt((1.0f - std::cos(threshold_fov)) /
171 (1.0f - std::cos(zoom_fov / 2.0f))));
174 void setPitchYawRollRad(core::matrix4 &m, const v3f &rot)
176 f64 a1 = rot.Z, a2 = rot.X, a3 = rot.Y;
177 f64 c1 = cos(a1), s1 = sin(a1);
178 f64 c2 = cos(a2), s2 = sin(a2);
179 f64 c3 = cos(a3), s3 = sin(a3);
180 f32 *M = m.pointer();
182 M[0] = s1 * s2 * s3 + c1 * c3;
184 M[2] = s1 * s2 * c3 - c1 * s3;
186 M[4] = c1 * s2 * s3 - s1 * c3;
188 M[6] = c1 * s2 * c3 + s1 * s3;
195 v3f getPitchYawRollRad(const core::matrix4 &m)
197 const f32 *M = m.pointer();
199 f64 a1 = atan2(M[1], M[5]);
200 f32 c2 = std::sqrt((f64)M[10]*M[10] + (f64)M[8]*M[8]);
201 f32 a2 = atan2f(-M[9], c2);
204 f32 a3 = atan2f(s1*M[6] - c1*M[2], c1*M[0] - s1*M[4]);
206 return v3f(a2, a3, a1);