scummvm/scumm/usage_bits.cpp
Paweł Kołodziejski aa3766018f updated copyrights headers
svn-id: r6726
2003-03-06 21:46:56 +00:00

83 lines
2.3 KiB
C++

/* ScummVM - Scumm Interpreter
* Copyright (C) 2002-2003 The ScummVM project
*
* 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "stdafx.h"
#include "scumm.h"
#include "usage_bits.h"
void Scumm::upgradeGfxUsageBits() {
int i;
for (i = 409; i >= 0; i--) {
bool dirty_bit = ((gfxUsageBits[i] & 0x80000000) != 0);
bool restored_bit = ((gfxUsageBits[i] & 0x40000000) != 0);
gfxUsageBits[3 * i] = gfxUsageBits[i] & 0x3FFFFFFF;
if (dirty_bit)
setGfxUsageBit(i, USAGE_BIT_DIRTY);
if (restored_bit)
setGfxUsageBit(i, USAGE_BIT_RESTORED);
}
}
void Scumm::setGfxUsageBit(int strip, int bit) {
assert(1 <= bit && bit <= 96);
bit--;
gfxUsageBits[3 * strip + bit / 32] |= (1 << (bit % 32));
}
void Scumm::clearGfxUsageBit(int strip, int bit) {
assert(1 <= bit && bit <= 96);
bit--;
gfxUsageBits[3 * strip + bit / 32] &= ~(1 << (bit % 32));
}
bool Scumm::testGfxUsageBit(int strip, int bit) {
assert(1 <= bit && bit <= 96);
bit--;
return (gfxUsageBits[3 * strip + bit / 32] & (1 << (bit % 32))) != 0;
}
bool Scumm::testGfxAnyUsageBits(int strip) {
// Exclude the DIRTY and RESTORED bits from the test
uint32 bitmask[3] = { 0xFFFFFFFF, 0xFFFFFFFF, 0x3FFFFFFF };
int i;
for (i = 0; i < 3; i++)
if (gfxUsageBits[3 * strip + i] & bitmask[i])
return true;
return false;
}
bool Scumm::testGfxOtherUsageBits(int strip, int bit) {
// Don't exclude the DIRTY and RESTORED bits from the test
uint32 bitmask[3] = { 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
int i;
assert(1 <= bit && bit <= 96);
bit--;
bitmask[bit / 32] &= ~(1 << (bit % 32));
for (i = 0; i < 3; i++)
if (gfxUsageBits[3 * strip + i] & bitmask[i])
return true;
return false;
}