raze-gles/source/core/interpolate.cpp
Christoph Oelckers 27c313d74e - moved interpolation code to its own file.
Mainly to get it out of the way. This needs to be redone later in a more serialization-friendly way.
2020-06-21 22:36:05 +02:00

142 lines
3.8 KiB
C++

//-------------------------------------------------------------------------
/*
Copyright (C) 1997, 2005 - 3D Realms Entertainment
This file is part of Shadow Warrior version 1.2
Shadow Warrior 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.
Original Source: 1997 - Frank Maddin and Jim Norwood
Prepared for public release: 03/28/2005 - Charlie Wiederhold, 3D Realms
*/
//-------------------------------------------------------------------------
#include "ns.h"
#include "interp.h"
#include "m_fixed.h"
#define (MAXINTERPOLATIONS 16384 + 256)
static int recursions = 0;
static int numinterpolations = 0;
// Not used yet. The entire interpolation feature as-is is highly serialization unfriendly because it only stores pointers without context, meaning there is no safe way to store them in a savegame without constantly risking breakage.
// Todo: This really needs to be made serialization friendly
struct Interpolation
{
int oldipos;
int bakipos;
void *curipos;
bool isshort;
};
static Interpolation interpolations[MAXINTERPOLATIONS];
void setinterpolation(void *posptr, bool isshort)
{
if (numinterpolations >= MAXINTERPOLATIONS)
return;
for (int i = numinterpolations - 1; i >= 0; i--)
{
if (interpolations[i].curipos == posptr)
return;
}
interpolations[numinterpolations].curipos = posptr;
interpolations[numinterpolations].oldipos = *posptr;
numinterpolations++;
}
void setinterpolation(int *posptr)
{
setinterpolation(posptr, false);
}
// only used by SW to interpolate floorheinum and ceilingheinum
void setinterpolation(short *posptr)
{
setinterpolation(posptr, true);
}
void stopinterpolation(void *posptr)
{
for (int i = numinterpolations - 1; i >= 0; i--)
{
if (curipos[i] == posptr)
{
numinterpolations--;
interpolations[i] = interpolations[numinterpolations];
}
}
}
void updateinterpolations(void) // Stick at beginning of domovethings
{
int i;
for (int i = numinterpolations - 1; i >= 0; i--)
interpolations[i].oldipos = interpolations[i].isshort? *(short*)interpolations[i].curipos : *(int*)interpolations[i].curipos;
}
// must call restore for every do interpolations
// make sure you don't exit
void dointerpolations(int smoothratio) // Stick at beginning of drawscreen
{
if (recursions++)
return;
int i, j, odelta, ndelta;
ndelta = 0;
j = 0;
for (i = numinterpolations - 1; i >= 0; i--)
{
bakipos[i] = *curipos[i];
odelta = ndelta;
ndelta = (*curipos[i]) - oldipos[i];
if (odelta != ndelta)
j = FixedMul(ndelta, smoothratio);
*curipos[i] = oldipos[i] + j;
}
}
void restoreinterpolations(bool force) // Stick at end of drawscreen
{
int i;
if (!force && --recursions)
return;
recursions = 0; // if interpolations are forcibly restored, the recursion counter must also be reset.
for (i = numinterpolations - 1; i >= 0; i--)
*curipos[i] = bakipos[i];
}
void togglespriteinterpolation(spritetype *sp, int set)
{
auto func = set ? setinterpolation : stopinterpolation;
func(&sp->x);
func(&sp->y);
func(&sp->z);
}