minetest/src/utility.cpp

453 lines
10 KiB
C++

/*
Minetest-c55
Copyright (C) 2010 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 General Public License as published by
the Free Software Foundation; either version 2 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 General Public License for more details.
You should have received a copy of the GNU 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.
*/
/*
(c) 2010 Perttu Ahola <celeron55@gmail.com>
*/
#include "utility.h"
#include "gettime.h"
#include "sha1.h"
#include "base64.h"
#include "log.h"
#include <iomanip>
TimeTaker::TimeTaker(const char *name, u32 *result)
{
m_name = name;
m_result = result;
m_running = true;
m_time1 = getTimeMs();
}
u32 TimeTaker::stop(bool quiet)
{
if(m_running)
{
u32 time2 = getTimeMs();
u32 dtime = time2 - m_time1;
if(m_result != NULL)
{
(*m_result) += dtime;
}
else
{
if(quiet == false)
infostream<<m_name<<" took "<<dtime<<"ms"<<std::endl;
}
m_running = false;
return dtime;
}
return 0;
}
u32 TimeTaker::getTime()
{
u32 time2 = getTimeMs();
u32 dtime = time2 - m_time1;
return dtime;
}
const v3s16 g_6dirs[6] =
{
// +right, +top, +back
v3s16( 0, 0, 1), // back
v3s16( 0, 1, 0), // top
v3s16( 1, 0, 0), // right
v3s16( 0, 0,-1), // front
v3s16( 0,-1, 0), // bottom
v3s16(-1, 0, 0) // left
};
const v3s16 g_26dirs[26] =
{
// +right, +top, +back
v3s16( 0, 0, 1), // back
v3s16( 0, 1, 0), // top
v3s16( 1, 0, 0), // right
v3s16( 0, 0,-1), // front
v3s16( 0,-1, 0), // bottom
v3s16(-1, 0, 0), // left
// 6
v3s16(-1, 1, 0), // top left
v3s16( 1, 1, 0), // top right
v3s16( 0, 1, 1), // top back
v3s16( 0, 1,-1), // top front
v3s16(-1, 0, 1), // back left
v3s16( 1, 0, 1), // back right
v3s16(-1, 0,-1), // front left
v3s16( 1, 0,-1), // front right
v3s16(-1,-1, 0), // bottom left
v3s16( 1,-1, 0), // bottom right
v3s16( 0,-1, 1), // bottom back
v3s16( 0,-1,-1), // bottom front
// 18
v3s16(-1, 1, 1), // top back-left
v3s16( 1, 1, 1), // top back-right
v3s16(-1, 1,-1), // top front-left
v3s16( 1, 1,-1), // top front-right
v3s16(-1,-1, 1), // bottom back-left
v3s16( 1,-1, 1), // bottom back-right
v3s16(-1,-1,-1), // bottom front-left
v3s16( 1,-1,-1), // bottom front-right
// 26
};
const v3s16 g_27dirs[27] =
{
// +right, +top, +back
v3s16( 0, 0, 1), // back
v3s16( 0, 1, 0), // top
v3s16( 1, 0, 0), // right
v3s16( 0, 0,-1), // front
v3s16( 0,-1, 0), // bottom
v3s16(-1, 0, 0), // left
// 6
v3s16(-1, 1, 0), // top left
v3s16( 1, 1, 0), // top right
v3s16( 0, 1, 1), // top back
v3s16( 0, 1,-1), // top front
v3s16(-1, 0, 1), // back left
v3s16( 1, 0, 1), // back right
v3s16(-1, 0,-1), // front left
v3s16( 1, 0,-1), // front right
v3s16(-1,-1, 0), // bottom left
v3s16( 1,-1, 0), // bottom right
v3s16( 0,-1, 1), // bottom back
v3s16( 0,-1,-1), // bottom front
// 18
v3s16(-1, 1, 1), // top back-left
v3s16( 1, 1, 1), // top back-right
v3s16(-1, 1,-1), // top front-left
v3s16( 1, 1,-1), // top front-right
v3s16(-1,-1, 1), // bottom back-left
v3s16( 1,-1, 1), // bottom back-right
v3s16(-1,-1,-1), // bottom front-left
v3s16( 1,-1,-1), // bottom front-right
// 26
v3s16(0,0,0),
};
static unsigned long next = 1;
/* RAND_MAX assumed to be 32767 */
int myrand(void)
{
next = next * 1103515245 + 12345;
return((unsigned)(next/65536) % 32768);
}
void mysrand(unsigned seed)
{
next = seed;
}
int myrand_range(int min, int max)
{
if(max-min > MYRAND_MAX)
{
errorstream<<"WARNING: myrand_range: max-min > MYRAND_MAX"<<std::endl;
assert(0);
}
if(min > max)
{
assert(0);
return max;
}
return (myrand()%(max-min+1))+min;
}
/*
blockpos: 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
*/
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;
// Distance in camera direction (+=front, -=back)
f32 dforward = blockpos_relative.dotProduct(camera_dir);
// Total distance
f32 d = blockpos_relative.getLength();
if(distance_ptr)
*distance_ptr = d;
// If block is very close, it is always in sight
if(d < 1.44*1.44*MAP_BLOCKSIZE*BS/2)
return true;
// If block is far away, it's not in sight
if(d > range)
return false;
// Maximum radius of a block
f32 block_max_radius = 0.5*1.44*1.44*MAP_BLOCKSIZE*BS;
// If block is (nearly) touching the camera, don't
// bother validating further (that is, render it anyway)
if(d < block_max_radius)
return true;
// Cosine of the angle between the camera direction
// and the block direction (camera_dir is an unit vector)
f32 cosangle = dforward / d;
// Compensate for the size of the block
// (as the block has to be shown even if it's a bit off FOV)
// This is an estimate, plus an arbitary factor
cosangle += block_max_radius / d * 0.5;
// If block is not in the field of view, skip it
if(cosangle < cos(camera_fov / 2))
return false;
return true;
}
// Creates a string encoded in JSON format (almost equivalent to a C string literal)
std::string serializeJsonString(const std::string &plain)
{
std::ostringstream os(std::ios::binary);
os<<"\"";
for(size_t i = 0; i < plain.size(); i++)
{
char c = plain[i];
switch(c)
{
case '"': os<<"\\\""; break;
case '\\': os<<"\\\\"; break;
case '/': os<<"\\/"; break;
case '\b': os<<"\\b"; break;
case '\f': os<<"\\f"; break;
case '\n': os<<"\\n"; break;
case '\r': os<<"\\r"; break;
case '\t': os<<"\\t"; break;
default:
{
if(c >= 32 && c <= 126)
{
os<<c;
}
else
{
u32 cnum = (u32) (u8) c;
os<<"\\u"<<std::hex<<std::setw(4)<<std::setfill('0')<<cnum;
}
break;
}
}
}
os<<"\"";
return os.str();
}
// Reads a string encoded in JSON format
std::string deSerializeJsonString(std::istream &is)
{
std::ostringstream os(std::ios::binary);
char c, c2;
// Parse initial doublequote
is >> c;
if(c != '"')
throw SerializationError("JSON string must start with doublequote");
// Parse characters
for(;;)
{
c = is.get();
if(is.eof())
throw SerializationError("JSON string ended prematurely");
if(c == '"')
{
return os.str();
}
else if(c == '\\')
{
c2 = is.get();
if(is.eof())
throw SerializationError("JSON string ended prematurely");
switch(c2)
{
default: os<<c2; break;
case 'b': os<<'\b'; break;
case 'f': os<<'\f'; break;
case 'n': os<<'\n'; break;
case 'r': os<<'\r'; break;
case 't': os<<'\t'; break;
case 'u':
{
char hexdigits[4+1];
is.read(hexdigits, 4);
if(is.eof())
throw SerializationError("JSON string ended prematurely");
hexdigits[4] = 0;
std::istringstream tmp_is(hexdigits, std::ios::binary);
int hexnumber;
tmp_is >> std::hex >> hexnumber;
os<<((char)hexnumber);
break;
}
}
}
else
{
os<<c;
}
}
return os.str();
}
// Get an sha-1 hash of the player's name combined with
// the password entered. That's what the server uses as
// their password. (Exception : if the password field is
// blank, we send a blank password - this is for backwards
// compatibility with password-less players).
std::string translatePassword(std::string playername, std::wstring password)
{
if(password.length() == 0)
return "";
std::string slt = playername + wide_to_narrow(password);
SHA1 sha1;
sha1.addBytes(slt.c_str(), slt.length());
unsigned char *digest = sha1.getDigest();
std::string pwd = base64_encode(digest, 20);
free(digest);
return pwd;
}
PointedThing::PointedThing():
type(POINTEDTHING_NOTHING),
node_undersurface(0,0,0),
node_abovesurface(0,0,0),
object_id(-1)
{}
std::string PointedThing::dump() const
{
std::ostringstream os(std::ios::binary);
if(type == POINTEDTHING_NOTHING)
{
os<<"[nothing]";
}
else if(type == POINTEDTHING_NODE)
{
const v3s16 &u = node_undersurface;
const v3s16 &a = node_abovesurface;
os<<"[node under="<<u.X<<","<<u.Y<<","<<u.Z
<< " above="<<a.X<<","<<a.Y<<","<<a.Z<<"]";
}
else if(type == POINTEDTHING_OBJECT)
{
os<<"[object "<<object_id<<"]";
}
else
{
os<<"[unknown PointedThing]";
}
return os.str();
}
void PointedThing::serialize(std::ostream &os) const
{
writeU8(os, 0); // version
writeU8(os, (u8)type);
if(type == POINTEDTHING_NOTHING)
{
// nothing
}
else if(type == POINTEDTHING_NODE)
{
writeV3S16(os, node_undersurface);
writeV3S16(os, node_abovesurface);
}
else if(type == POINTEDTHING_OBJECT)
{
writeS16(os, object_id);
}
}
void PointedThing::deSerialize(std::istream &is)
{
int version = readU8(is);
if(version != 0) throw SerializationError(
"unsupported PointedThing version");
type = (PointedThingType) readU8(is);
if(type == POINTEDTHING_NOTHING)
{
// nothing
}
else if(type == POINTEDTHING_NODE)
{
node_undersurface = readV3S16(is);
node_abovesurface = readV3S16(is);
}
else if(type == POINTEDTHING_OBJECT)
{
object_id = readS16(is);
}
else
{
throw SerializationError(
"unsupported PointedThingType");
}
}
bool PointedThing::operator==(const PointedThing &pt2) const
{
if(type != pt2.type)
return false;
if(type == POINTEDTHING_NODE)
{
if(node_undersurface != pt2.node_undersurface)
return false;
if(node_abovesurface != pt2.node_abovesurface)
return false;
}
else if(type == POINTEDTHING_OBJECT)
{
if(object_id != pt2.object_id)
return false;
}
return true;
}
bool PointedThing::operator!=(const PointedThing &pt2) const
{
return !(*this == pt2);
}