games/minimal/mods/default/textures/default_sapling.png

/*
Minetest
Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@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 "numeric.h"

#include "log.h"
#include "constants.h" // BS, MAP_BLOCKSIZE
#include "noise.h" // PseudoRandom, PcgRandom
#include "threading/mutex_auto_lock.h"
#include <cstring>
#include <cmath>


// myrand

PcgRandom g_pcgrand;

u32 myrand()
{
	return g_pcgrand.next();
}

void mysrand(unsigned int seed)
{
	g_pcgrand.seed(seed);
}

void myrand_bytes(void *out, size_t len)
{
	g_pcgrand.bytes(out, len);
}

int myrand_range(int min, int max)
{
	return g_pcgrand.range(min, max);
}


/*
	64-bit unaligned version of MurmurHash
*/
u64 murmur_hash_64_ua(const void *key, int len, unsigned int seed)
{
	const u64 m = 0xc6a4a7935bd1e995ULL;
	const int r = 47;
	u64 h = seed ^ (len * m);

	const u8 *data = (const u8 *)key;
	const u8 *end = data + (len / 8) * 8;

	while (data != end) {
		u64 k;
		memcpy(&k, data, sizeof(u64));
		data += sizeof(u64);

		k *= m;
		k ^= k >> r;
		k *= m;

		h ^= k;
		h *= m;
	}

	const unsigned char *data2 = (const unsigned char *)data;
	switch (len & 7) {
		case 7: h ^= (u64)data2[6] << 48;
		case 6: h ^= (u64)data2[5] << 40;
		case 5: h ^= (u64)data2[4] << 32;
		case 4: h ^= (u64)data2[3] << 24;
		case 3: h ^= (u64)data2[2] << 16;
		case 2: h ^= (u64)data2[1] << 8;
		case 1: h ^= (u64)data2[0];
				h *= m;
	}

	h ^= h >> r;
	h *= m;
	h ^= h >> r;

	return h;
}

/*
	blockpos_b: position of block in block coordinates
	camera_pos: position of camera in nodes
	camera_dir: an unit vector pointing to camera direction
	range: viewing range
	distance_ptr: return location for distance from the camera
*/
bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir,
		f32 camera_fov, f32 range, f32 *distance_ptr)
{
	v3s16 blockpos_nodes = blockpos_b * MAP_BLOCKSIZE;

	// Block center position
	v3f blockpos(
			((float)blockpos_nodes.X + MAP_BLOCKSIZE/2) * BS,
			((float)blockpos_nodes.Y + MAP_BLOCKSIZE/2) * BS,
			((float)blockpos_nodes.Z + MAP_BLOCKSIZE/2) * BS
	);

	// Block position relative to camera
	v3f blockpos_relative = blockpos - camera_pos;

	// Total distance
	f32 d = MYMAX(0, blockpos_relative.getLength() - BLOCK_MAX_RADIUS);

	if (distance_ptr)
		*distance_ptr = d;

	// If block is far away, it's not in sight
	if (d > range)
		return false;

	// If block is (nearly) touching the camera, don't
	// bother validating further (that is, render it anyway)
	if (d == 0)
		return true;

	// Adjust camera position, for purposes of computing the angle,
	// such that a block that has any portion visible with the
	// current camera position will have the center visible at the
	// adjusted postion
	f32 adjdist = BLOCK_MAX_RADIUS / cos((M_PI - camera_fov) / 2);

	// Block position relative to adjusted camera
	v3f blockpos_adj = blockpos - (camera_pos - camera_dir * adjdist);

	// Distance in camera direction (+=front, -=back)
	f32 dforward = blockpos_adj.dotProduct(camera_dir);

	// Cosine of the angle between the camera direction
	// and the block direction (camera_dir is an unit vector)
	f32 cosangle = dforward / blockpos_adj.getLength();

	// If block is not in the field of view, skip it
	// HOTFIX: use sligthly increased angle (+10%) to fix too agressive
	// culling. Somebody have to find out whats wrong with the math here.
	// Previous value: camera_fov / 2
	if (cosangle < std::cos(camera_fov * 0.55f))
		return false;

	return true;
}

inline float adjustDist(float dist, float zoom_fov)
{
	// 1.775 ~= 72 * PI / 180 * 1.4, the default FOV on the client.
	// The heuristic threshold for zooming is half of that.
	static constexpr const float threshold_fov = 1.775f / 2.0f;
	if (zoom_fov < 0.001f || zoom_fov > threshold_fov)
		return dist;

	return dist * std::cbrt((1.0f - std::cos(threshold_fov)) /
		(1.0f - std::cos(zoom_fov / 2.0f)));
}

s16 adjustDist(s16 dist, float zoom_fov)
{
	return std::round(adjustDist((float)dist, zoom_fov));
}

void setPitchYawRollRad(core::matrix4 &m, const v3f &rot)
{
	f64 a1 = rot.Z, a2 = rot.X, a3 = rot.Y;
	f64 c1 = cos(a1), s1 = sin(a1);
	f64 c2 = cos(a2), s2 = sin(a2);
	f64 c3 = cos(a3), s3 = sin(a3);
	f32 *M = m.pointer();

	M[0] = s1 * s2 * s3 + c1 * c3;
	M[1] = s1 * c2;
	M[2] = s1 * s2 * c3 - c1 * s3;

	M[4] = c1 * s2 * s3 - s1 * c3;
	M[5] = c1 * c2;
	M[6] = c1 * s2 * c3 + s1 * s3;

	M[8] = c2 * s3;
	M[9] = -s2;
	M[10] = c2 * c3;
}

v3f getPitchYawRollRad(const core::matrix4 &m)
{
	const f32 *M = m.pointer();

	f64 a1 = atan2(M[1], M[5]);
	f32 c2 = std::sqrt((f64)M[10]*M[10] + (f64)M[8]*M[8]);
	f32 a2 = atan2f(-M[9], c2);
	f64 c1 = cos(a1);
	f64 s1 = sin(a1);
	f32 a3 = atan2f(s1*M[6] - c1*M[2], c1*M[0] - s1*M[4]);

	return v3f(a2, a3, a1);
}
ofs	hex dump	ascii
0000	89 50 4e 47 0d 0a 1a 0a 00 00 00 0d 49 48 44 52 00 00 00 10 00 00 00 10 08 03 00 00 00 28 2d 0f	.PNG........IHDR.............(-.
0020	53 00 00 00 78 50 4c 54 45 00 00 00 34 6c 0c 43 7c 04 54 a6 01 10 36 00 14 4c 00 1a 21 07 1c 4d	S...xPLTE...4l.C\|.T...6..L..!..M
0040	00 1d 36 08 1d 4a 03 1e 45 07 1e 48 04 1e 51 00 1f 2a 0d 24 36 11 28 21 11 28 38 10 2a 51 0a 2b	..6..J..E..H..Q...$6.(!.(8.Q.+
0060	24 14 2b 74 00 2c 23 1e 2c 65 01 2d 29 18 2f 24 16 30 3e 19 34 69 0c 34 6c 0c 36 73 00 37 2a 18	$.+t.,#.,e.-)./$.0>.4i.4l.6s.7*.
0080	3b 22 14 3f 2a 18 43 7c 04 44 7a 12 47 79 14 57 a0 00 5e a5 0f 6b 55 30 6e 41 2b 6f 57 2e 73 56	;".?*.C\|.Dz.Gy.W..^..kU0nA+oW.sV
00a0	2b 41 fd da 5a 00 00 00 04 74 52 4e 53 00 00 00 00 b3 93 66 9a 00 00 00 7b 49 44 41 54 78 da 8d	+A..Z....tRNS......f....{IDATx..
00c0	8e 5b 0e c2 30 0c 04 31 af 42 4b a1 01 d2 92 71 0b 84 e7 fd 6f 48 22 14 41 24 3e f0 8f e5 d1 68	.[..0..1.BK....q....oH".A$>....h
00e0	bd a3 5f 33 a1 a8 f8 06 c2 d9 1a 03 a4 db a3 a8 36 8b 04 82 0f ce cd a7 49 09 fe 5a a1 86 ea 0d	.._3............6.......I..Z....
0100	3c ba a4 3c 1d c0 22 11 80 bb ee 40 f1 94 e3 08 ac 01 b8 b8 55 ca 90 f8 80 19 b5 c8 a7 ca b6 bf	<..<.."....@........U...........
0120	f7 59 d9 63 7b 6b 33 b0 ef 1e 5d 06 36 c3 73 08 eb af 8c 17 9a 37 0a 24 a7 09 6a 1e 00 00 00 00	.Y.c{k3...].6.s......7.$..j.....
0140	49 45 4e 44 ae 42 60 82	IEND.B`.