advtrains/textures/advtrains_couple.png

/*
Minetest
Copyright (C) 2010-2015 kwolekr, Ryan Kwolek <kwolekr@minetest.net>

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 "objdef.h"
#include "util/numeric.h"
#include "log.h"
#include "gamedef.h"

ObjDefManager::ObjDefManager(IGameDef *gamedef, ObjDefType type)
{
	m_objtype = type;
	m_ndef = gamedef ? gamedef->getNodeDefManager() : NULL;
}


ObjDefManager::~ObjDefManager()
{
	for (size_t i = 0; i != m_objects.size(); i++)
		delete m_objects[i];
}


ObjDefHandle ObjDefManager::add(ObjDef *obj)
{
	assert(obj);

	if (obj->name.length() && getByName(obj->name))
		return OBJDEF_INVALID_HANDLE;

	u32 index = addRaw(obj);
	if (index == OBJDEF_INVALID_INDEX)
		return OBJDEF_INVALID_HANDLE;

	obj->handle = createHandle(index, m_objtype, obj->uid);
	return obj->handle;
}


ObjDef *ObjDefManager::get(ObjDefHandle handle) const
{
	u32 index = validateHandle(handle);
	return (index != OBJDEF_INVALID_INDEX) ? getRaw(index) : NULL;
}


ObjDef *ObjDefManager::set(ObjDefHandle handle, ObjDef *obj)
{
	u32 index = validateHandle(handle);
	if (index == OBJDEF_INVALID_INDEX)
		return NULL;

	ObjDef *oldobj = setRaw(index, obj);

	obj->uid    = oldobj->uid;
	obj->index  = oldobj->index;
	obj->handle = oldobj->handle;

	return oldobj;
}


u32 ObjDefManager::addRaw(ObjDef *obj)
{
	size_t nobjects = m_objects.size();
	if (nobjects >= OBJDEF_MAX_ITEMS)
		return -1;

	obj->index = nobjects;

	// Ensure UID is nonzero so that a valid handle == OBJDEF_INVALID_HANDLE
	// is not possible.  The slight randomness bias isn't very significant.
	obj->uid = myrand() & OBJDEF_UID_MASK;
	if (obj->uid == 0)
		obj->uid = 1;

	m_objects.push_back(obj);

	infostream << "ObjDefManager: added " << getObjectTitle()
		<< ": name=\"" << obj->name
		<< "\" index=" << obj->index
		<< " uid="     << obj->uid
		<< std::endl;

	return nobjects;
}


ObjDef *ObjDefManager::getRaw(u32 index) const
{
	return m_objects[index];
}


ObjDef *ObjDefManager::setRaw(u32 index, ObjDef *obj)
{
	ObjDef *old_obj = m_objects[index];
	m_objects[index] = obj;
	return old_obj;
}


ObjDef *ObjDefManager::getByName(const std::string &name) const
{
	for (size_t i = 0; i != m_objects.size(); i++) {
		ObjDef *obj = m_objects[i];
		if (obj && !strcasecmp(name.c_str(), obj->name.c_str()))
			return obj;
	}

	return NULL;
}


void ObjDefManager::clear()
{
	for (size_t i = 0; i != m_objects.size(); i++)
		delete m_objects[i];

	m_objects.clear();
}


u32 ObjDefManager::validateHandle(ObjDefHandle handle) const
{
	ObjDefType type;
	u32 index;
	u32 uid;

	bool is_valid =
		(handle != OBJDEF_INVALID_HANDLE)         &&
		decodeHandle(handle, &index, &type, &uid) &&
		(type == m_objtype)                       &&
		(index < m_objects.size())                &&
		(m_objects[index]->uid == uid);

	return is_valid ? index : -1;
}


ObjDefHandle ObjDefManager::createHandle(u32 index, ObjDefType type, u32 uid)
{
	ObjDefHandle handle = 0;
	set_bits(&handle, 0, 18, index);
	set_bits(&handle, 18, 6, type);
	set_bits(&handle, 24, 7, uid);

	u32 parity = calc_parity(handle);
	set_bits(&handle, 31, 1, parity);

	return handle ^ OBJDEF_HANDLE_SALT;
}


bool ObjDefManager::decodeHandle(ObjDefHandle handle, u32 *index,
	ObjDefType *type, u32 *uid)
{
	handle ^= OBJDEF_HANDLE_SALT;

	u32 parity = get_bits(handle, 31, 1);
	set_bits(&handle, 31, 1, 0);
	if (parity != calc_parity(handle))
		return false;

	*index = get_bits(handle, 0, 18);
	*type  = (ObjDefType)get_bits(handle, 18, 6);
	*uid   = get_bits(handle, 24, 7);
	return true;
}
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 06 00 00 00 1f f3 ff	.PNG........IHDR................
0020	61 00 00 00 06 62 4b 47 44 00 ff 00 ff 00 ff a0 bd a7 93 00 00 00 09 70 48 59 73 00 00 0b 13 00	a....bKGD..............pHYs.....
0040	00 0b 13 01 00 9a 9c 18 00 00 00 07 74 49 4d 45 07 e1 07 1d 0b 27 1b 5d 6a a5 bd 00 00 00 1d 69	............tIME.....'.]j......i
0060	54 58 74 43 6f 6d 6d 65 6e 74 00 00 00 00 00 43 72 65 61 74 65 64 20 77 69 74 68 20 47 49 4d 50	TXtComment.....Created.with.GIMP
0080	64 2e 65 07 00 00 00 b7 49 44 41 54 38 cb a5 92 c1 0e 83 20 10 44 df 92 26 fa ad 3d c9 7e 08 f6	d.e.....IDAT8........D..&..=.~..
00a0	d4 6f f5 e4 f4 a0 28 88 1e aa 9b 10 26 01 66 e7 01 26 89 27 15 00 0c 7b 66 20 74 db 24 64 71 d7	.o....(.....&.f..&.'...{f.t.$dq.
00c0	64 31 e8 c3 66 92 75 33 5f e8 17 00 d3 bc 2f 4e 33 86 a1 b3 34 87 7d 5b 02 77 97 bf 07 95 38 55	d1..f.u3_...../N3...4.}[.w....8U
00e0	95 9d 01 7f 0f 72 f7 65 53 8c 51 ea 0c 49 95 56 67 54 7a 9d 63 8c 2a 75 e0 61 99 24 72 9c f4 fd	.....r.eS.Q..I.VgTz.c.*u.a.$r...
0100	58 66 a3 0f a7 cc f4 81 8c 9b 52 6a 23 49 02 d1 c6 5f c7 11 39 54 dd 56 dd 5c e2 f1 32 8b 64 15	Xf........Rj#I..._..9T.V.\..2.d.
0120	c2 98 46 bb 3c 5c be 42 46 4e 69 8f 87 a8 a2 5e 8d 0d b9 44 58 3e 8e ee bf c2 bf 55 22 fc 00 53	..F.<\.BFNi....^...DX>.....U"..S
0140	66 b9 c5 63 21 f0 2e 00 00 00 00 49 45 4e 44 ae 42 60 82	f..c!......IEND.B`.