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gzdoom-gles/src/p_scroll.cpp

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//-----------------------------------------------------------------------------
//
// Copyright 1998-1998 Chi Hoang, Lee Killough, Jim Flynn, Rand Phares, Ty Halderman
// Copyright 1999-2016 Randy Heit
// Copyright 2002-2016 Christoph Oelckers
//
// 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 3 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, see http://www.gnu.org/licenses/
//
//-----------------------------------------------------------------------------
//
// DESCRIPTION:
// Initializes and implements BOOM linedef triggers for
// Scrollers/Conveyors
//
//-----------------------------------------------------------------------------
/* For code that originates from ZDoom the following applies:
**
**---------------------------------------------------------------------------
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1. Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in the
** documentation and/or other materials provided with the distribution.
** 3. The name of the author may not be used to endorse or promote products
** derived from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**---------------------------------------------------------------------------
**
*/
#include <stdlib.h>
#include "actor.h"
#include "p_spec.h"
#include "serializer.h"
#include "p_lnspec.h"
#include "r_data/r_interpolate.h"
#include "g_levellocals.h"
//-----------------------------------------------------------------------------
//
// killough 3/7/98: Add generalized scroll effects
//
//-----------------------------------------------------------------------------
class DScroller : public DThinker
{
DECLARE_CLASS (DScroller, DThinker)
HAS_OBJECT_POINTERS
public:
DScroller (EScroll type, double dx, double dy, int control, int affectee, int accel, EScrollPos scrollpos = EScrollPos::scw_all);
DScroller (double dx, double dy, const line_t *l, int control, int accel, EScrollPos scrollpos = EScrollPos::scw_all);
void OnDestroy() override;
void Serialize(FSerializer &arc);
void Tick ();
bool AffectsWall (int wallnum) const { return m_Type == EScroll::sc_side && m_Affectee == wallnum; }
int GetWallNum () const { return m_Type == EScroll::sc_side ? m_Affectee : -1; }
void SetRate (double dx, double dy) { m_dx = dx; m_dy = dy; }
bool IsType (EScroll type) const { return type == m_Type; }
int GetAffectee () const { return m_Affectee; }
EScrollPos GetScrollParts() const { return m_Parts; }
protected:
EScroll m_Type; // Type of scroll effect
double m_dx, m_dy; // (dx,dy) scroll speeds
int m_Affectee; // Number of affected sidedef, sector, tag, or whatever
int m_Control; // Control sector (-1 if none) used to control scrolling
double m_LastHeight; // Last known height of control sector
double m_vdx, m_vdy; // Accumulated velocity if accelerative
int m_Accel; // Whether it's accelerative
EScrollPos m_Parts; // Which parts of a sidedef are being scrolled?
TObjPtr<DInterpolation*> m_Interpolations[3];
private:
DScroller ()
{
}
};
IMPLEMENT_CLASS(DScroller, false, true)
IMPLEMENT_POINTERS_START(DScroller)
IMPLEMENT_POINTER(m_Interpolations[0])
IMPLEMENT_POINTER(m_Interpolations[1])
IMPLEMENT_POINTER(m_Interpolations[2])
IMPLEMENT_POINTERS_END
//-----------------------------------------------------------------------------
//
//
//
//-----------------------------------------------------------------------------
EScrollPos operator &(EScrollPos one, EScrollPos two)
{
return EScrollPos(int(one) & int(two));
}
//-----------------------------------------------------------------------------
//
//
//
//-----------------------------------------------------------------------------
void DScroller::Serialize(FSerializer &arc)
{
Super::Serialize (arc);
arc.Enum("type", m_Type)
("dx", m_dx)
("dy", m_dy)
("affectee", m_Affectee)
("control", m_Control)
("lastheight", m_LastHeight)
("vdx", m_vdx)
("vdy", m_vdy)
("accel", m_Accel)
.Enum("parts", m_Parts)
.Array("interpolations", m_Interpolations, 3);
}
//-----------------------------------------------------------------------------
//
// [RH] Compensate for rotated sector textures by rotating the scrolling
// in the opposite direction.
//
//-----------------------------------------------------------------------------
static void RotationComp(const sector_t *sec, int which, double dx, double dy, double &tdx, double &tdy)
{
DAngle an = sec->GetAngle(which);
if (an == 0)
{
tdx = dx;
tdy = dy;
}
else
{
double ca = -an.Cos();
double sa = -an.Sin();
tdx = dx*ca - dy*sa;
tdy = dy*ca + dx*sa;
}
}
//-----------------------------------------------------------------------------
//
// killough 2/28/98:
//
// This function, with the help of r_plane.c and r_bsp.c, supports generalized
// scrolling floors and walls, with optional mobj-carrying properties, e.g.
// conveyor belts, rivers, etc. A linedef with a special type affects all
// tagged sectors the same way, by creating scrolling and/or object-carrying
// properties. Multiple linedefs may be used on the same sector and are
// cumulative, although the special case of scrolling a floor and carrying
// things on it, requires only one linedef. The linedef's direction determines
// the scrolling direction, and the linedef's length determines the scrolling
// speed. This was designed so that an edge around the sector could be used to
// control the direction of the sector's scrolling, which is usually what is
// desired.
//
// Process the active scrollers.
//
// This is the main scrolling code
// killough 3/7/98
//
//-----------------------------------------------------------------------------
void DScroller::Tick ()
{
double dx = m_dx, dy = m_dy, tdx, tdy;
if (m_Control != -1)
{ // compute scroll amounts based on a sector's height changes
double height = level.sectors[m_Control].CenterFloor () +
level.sectors[m_Control].CenterCeiling ();
double delta = height - m_LastHeight;
m_LastHeight = height;
dx *= delta;
dy *= delta;
}
// killough 3/14/98: Add acceleration
if (m_Accel)
{
m_vdx = dx += m_vdx;
m_vdy = dy += m_vdy;
}
if (dx == 0 && dy == 0)
return;
switch (m_Type)
{
case EScroll::sc_side: // killough 3/7/98: Scroll wall texture
if (m_Parts & EScrollPos::scw_top)
{
level.sides[m_Affectee].AddTextureXOffset(side_t::top, dx);
level.sides[m_Affectee].AddTextureYOffset(side_t::top, dy);
}
if (m_Parts & EScrollPos::scw_mid && (level.sides[m_Affectee].linedef->backsector == NULL ||
!(level.sides[m_Affectee].linedef->flags&ML_3DMIDTEX)))
{
level.sides[m_Affectee].AddTextureXOffset(side_t::mid, dx);
level.sides[m_Affectee].AddTextureYOffset(side_t::mid, dy);
}
if (m_Parts & EScrollPos::scw_bottom)
{
level.sides[m_Affectee].AddTextureXOffset(side_t::bottom, dx);
level.sides[m_Affectee].AddTextureYOffset(side_t::bottom, dy);
}
break;
case EScroll::sc_floor: // killough 3/7/98: Scroll floor texture
RotationComp(&level.sectors[m_Affectee], sector_t::floor, dx, dy, tdx, tdy);
level.sectors[m_Affectee].AddXOffset(sector_t::floor, tdx);
level.sectors[m_Affectee].AddYOffset(sector_t::floor, tdy);
break;
case EScroll::sc_ceiling: // killough 3/7/98: Scroll ceiling texture
RotationComp(&level.sectors[m_Affectee], sector_t::ceiling, dx, dy, tdx, tdy);
level.sectors[m_Affectee].AddXOffset(sector_t::ceiling, tdx);
level.sectors[m_Affectee].AddYOffset(sector_t::ceiling, tdy);
break;
// [RH] Don't actually carry anything here. That happens later.
case EScroll::sc_carry:
level.Scrolls[m_Affectee].X += dx;
level.Scrolls[m_Affectee].Y += dy;
// mark all potentially affected things here so that the very expensive calculation loop in AActor::Tick does not need to run for actors which do not touch a scrolling sector.
for (auto n = level.sectors[m_Affectee].touching_thinglist; n; n = n->m_snext)
{
n->m_thing->flags8 |= MF8_INSCROLLSEC;
}
break;
case EScroll::sc_carry_ceiling: // to be added later
break;
}
}
//-----------------------------------------------------------------------------
//
// Add_Scroller()
//
// Add a generalized scroller to the thinker list.
//
// type: the enumerated type of scrolling: floor, ceiling, floor carrier,
// wall, floor carrier & scroller
//
// (dx,dy): the direction and speed of the scrolling or its acceleration
//
// control: the sector whose heights control this scroller's effect
// remotely, or -1 if no control sector
//
// affectee: the index of the affected object (sector or sidedef)
//
// accel: non-zero if this is an accelerative effect
//
//-----------------------------------------------------------------------------
DScroller::DScroller (EScroll type, double dx, double dy,
int control, int affectee, int accel, EScrollPos scrollpos)
: DThinker (STAT_SCROLLER)
{
m_Type = type;
m_dx = dx;
m_dy = dy;
m_Accel = accel;
m_Parts = scrollpos;
m_vdx = m_vdy = 0;
m_LastHeight = 0;
if ((m_Control = control) != -1)
{
m_LastHeight =
level.sectors[control].CenterFloor() + level.sectors[control].CenterCeiling();
}
m_Affectee = affectee;
m_Interpolations[0] = m_Interpolations[1] = m_Interpolations[2] = NULL;
switch (type)
{
case EScroll::sc_carry:
level.AddScroller (affectee);
break;
case EScroll::sc_side:
level.sides[affectee].Flags |= WALLF_NOAUTODECALS;
if (m_Parts & EScrollPos::scw_top)
{
m_Interpolations[0] = level.sides[m_Affectee].SetInterpolation(side_t::top);
}
if (m_Parts & EScrollPos::scw_mid && (level.sides[m_Affectee].linedef->backsector == nullptr ||
!(level.sides[m_Affectee].linedef->flags&ML_3DMIDTEX)))
{
m_Interpolations[1] = level.sides[m_Affectee].SetInterpolation(side_t::mid);
}
if (m_Parts & EScrollPos::scw_bottom)
{
m_Interpolations[2] = level.sides[m_Affectee].SetInterpolation(side_t::bottom);
}
break;
case EScroll::sc_floor:
m_Interpolations[0] = level.sectors[affectee].SetInterpolation(sector_t::FloorScroll, false);
break;
case EScroll::sc_ceiling:
m_Interpolations[0] = level.sectors[affectee].SetInterpolation(sector_t::CeilingScroll, false);
break;
default:
break;
}
}
void DScroller::OnDestroy ()
{
for(int i=0;i<3;i++)
{
if (m_Interpolations[i] != NULL)
{
m_Interpolations[i]->DelRef();
m_Interpolations[i] = NULL;
}
}
Super::OnDestroy();
}
//-----------------------------------------------------------------------------
//
// Adds wall scroller. Scroll amount is rotated with respect to wall's
// linedef first, so that scrolling towards the wall in a perpendicular
// direction is translated into vertical motion, while scrolling along
// the wall in a parallel direction is translated into horizontal motion.
//
// killough 5/25/98: cleaned up arithmetic to avoid drift due to roundoff
//
//-----------------------------------------------------------------------------
DScroller::DScroller (double dx, double dy, const line_t *l,
int control, int accel, EScrollPos scrollpos)
: DThinker (STAT_SCROLLER)
{
double x = fabs(l->Delta().X), y = fabs(l->Delta().Y), d;
if (y > x) d = x, x = y, y = d;
d = x / g_sin(g_atan2(y, x) + M_PI / 2);
x = -(dy * l->Delta().Y + dx * l->Delta().X) / d;
y = -(dx * l->Delta().Y - dy * l->Delta().X) / d;
m_Type = EScroll::sc_side;
m_dx = x;
m_dy = y;
m_vdx = m_vdy = 0;
m_Accel = accel;
m_Parts = scrollpos;
m_LastHeight = 0;
if ((m_Control = control) != -1)
m_LastHeight = level.sectors[control].CenterFloor() + level.sectors[control].CenterCeiling();
m_Affectee = l->sidedef[0]->Index();
level.sides[m_Affectee].Flags |= WALLF_NOAUTODECALS;
m_Interpolations[0] = m_Interpolations[1] = m_Interpolations[2] = NULL;
if (m_Parts & EScrollPos::scw_top)
{
m_Interpolations[0] = level.sides[m_Affectee].SetInterpolation(side_t::top);
}
if (m_Parts & EScrollPos::scw_mid && (level.sides[m_Affectee].linedef->backsector == NULL ||
!(level.sides[m_Affectee].linedef->flags&ML_3DMIDTEX)))
{
m_Interpolations[1] = level.sides[m_Affectee].SetInterpolation(side_t::mid);
}
if (m_Parts & EScrollPos::scw_bottom)
{
m_Interpolations[2] = level.sides[m_Affectee].SetInterpolation(side_t::bottom);
}
}
// Amount (dx,dy) vector linedef is shifted right to get scroll amount
#define SCROLL_SHIFT 5
#define SCROLLTYPE(i) EScrollPos(((i) <= 0) || ((i) & ~7) ? 7 : (i))
//-----------------------------------------------------------------------------
//
// Initialize the scrollers
//
//-----------------------------------------------------------------------------
void P_SpawnScrollers(void)
{
line_t *l = &level.lines[0];
TArray<int> copyscrollers;
for (auto &line : level.lines)
{
if (line.special == Sector_CopyScroller)
{
// don't allow copying the scroller if the sector has the same tag as it would just duplicate it.
if (!tagManager.SectorHasTag(line.frontsector, line.args[0]))
{
copyscrollers.Push(line.Index());
}
line.special = 0;
}
}
for (unsigned i = 0; i < level.lines.Size(); i++, l++)
{
double dx; // direction and speed of scrolling
double dy;
int control = -1, accel = 0; // no control sector or acceleration
int special = l->special;
// Check for undefined parameters that are non-zero and output messages for them.
// We don't report for specials we don't understand.
FLineSpecial *spec = P_GetLineSpecialInfo(special);
if (spec != NULL)
{
int max = spec->map_args;
for (unsigned arg = max; arg < countof(l->args); ++arg)
{
if (l->args[arg] != 0)
{
Printf("Line %d (type %d:%s), arg %u is %d (should be 0)\n",
i, special, spec->name, arg+1, l->args[arg]);
}
}
}
// killough 3/7/98: Types 245-249 are same as 250-254 except that the
// first side's sector's heights cause scrolling when they change, and
// this linedef controls the direction and speed of the scrolling. The
// most complicated linedef since donuts, but powerful :)
//
// killough 3/15/98: Add acceleration. Types 214-218 are the same but
// are accelerative.
// [RH] Assume that it's a scroller and zero the line's special.
l->special = 0;
dx = dy = 0; // Shut up, GCC
if (special == Scroll_Ceiling ||
special == Scroll_Floor ||
special == Scroll_Texture_Model)
{
if (l->args[1] & 3)
{
// if 1, then displacement
// if 2, then accelerative (also if 3)
control = l->sidedef[0]->sector->Index();
if (l->args[1] & 2)
accel = 1;
}
if (special == Scroll_Texture_Model ||
l->args[1] & 4)
{
// The line housing the special controls the
// direction and speed of scrolling.
dx = l->Delta().X / 32.;
dy = l->Delta().Y / 32.;
}
else
{
// The speed and direction are parameters to the special.
dx = (l->args[3] - 128) / 32.;
dy = (l->args[4] - 128) / 32.;
}
}
switch (special)
{
int s;
case Scroll_Ceiling:
{
FSectorTagIterator itr(l->args[0]);
while ((s = itr.Next()) >= 0)
{
Create<DScroller>(EScroll::sc_ceiling, -dx, dy, control, s, accel);
}
for (unsigned j = 0; j < copyscrollers.Size(); j++)
{
line_t *line = &level.lines[copyscrollers[j]];
if (line->args[0] == l->args[0] && (line->args[1] & 1))
{
Create<DScroller>(EScroll::sc_ceiling, -dx, dy, control, line->frontsector->Index(), accel);
}
}
break;
}
case Scroll_Floor:
if (l->args[2] != 1)
{ // scroll the floor texture
FSectorTagIterator itr(l->args[0]);
while ((s = itr.Next()) >= 0)
{
Create<DScroller> (EScroll::sc_floor, -dx, dy, control, s, accel);
}
for(unsigned j = 0;j < copyscrollers.Size(); j++)
{
line_t *line = &level.lines[copyscrollers[j]];
if (line->args[0] == l->args[0] && (line->args[1] & 2))
{
Create<DScroller>(EScroll::sc_floor, -dx, dy, control, line->frontsector->Index(), accel);
}
}
}
if (l->args[2] > 0)
{ // carry objects on the floor
FSectorTagIterator itr(l->args[0]);
while ((s = itr.Next()) >= 0)
{
Create<DScroller> (EScroll::sc_carry, dx, dy, control, s, accel);
}
for(unsigned j = 0;j < copyscrollers.Size(); j++)
{
line_t *line = &level.lines[copyscrollers[j]];
if (line->args[0] == l->args[0] && (line->args[1] & 4))
{
Create<DScroller> (EScroll::sc_carry, dx, dy, control, line->frontsector->Index(), accel);
}
}
}
break;
// killough 3/1/98: scroll wall according to linedef
// (same direction and speed as scrolling floors)
case Scroll_Texture_Model:
{
FLineIdIterator itr(l->args[0]);
while ((s = itr.Next()) >= 0)
{
if (s != (int)i)
Create<DScroller>(dx, dy, &level.lines[s], control, accel);
}
break;
}
case Scroll_Texture_Offsets:
// killough 3/2/98: scroll according to sidedef offsets
s = level.lines[i].sidedef[0]->Index();
Create<DScroller> (EScroll::sc_side, -level.sides[s].GetTextureXOffset(side_t::mid),
level.sides[s].GetTextureYOffset(side_t::mid), -1, s, accel, SCROLLTYPE(l->args[0]));
break;
case Scroll_Texture_Left:
l->special = special; // Restore the special, for compat_useblocking's benefit.
s = level.lines[i].sidedef[0]->Index();
Create<DScroller> (EScroll::sc_side, l->args[0] / 64., 0,
-1, s, accel, SCROLLTYPE(l->args[1]));
break;
case Scroll_Texture_Right:
l->special = special;
s = level.lines[i].sidedef[0]->Index();
Create<DScroller> (EScroll::sc_side, -l->args[0] / 64., 0,
-1, s, accel, SCROLLTYPE(l->args[1]));
break;
case Scroll_Texture_Up:
l->special = special;
s = level.lines[i].sidedef[0]->Index();
Create<DScroller> (EScroll::sc_side, 0, l->args[0] / 64.,
-1, s, accel, SCROLLTYPE(l->args[1]));
break;
case Scroll_Texture_Down:
l->special = special;
s = level.lines[i].sidedef[0]->Index();
Create<DScroller> (EScroll::sc_side, 0, -l->args[0] / 64.,
-1, s, accel, SCROLLTYPE(l->args[1]));
break;
case Scroll_Texture_Both:
s = level.lines[i].sidedef[0]->Index();
if (l->args[0] == 0) {
dx = (l->args[1] - l->args[2]) / 64.;
dy = (l->args[4] - l->args[3]) / 64.;
Create<DScroller> (EScroll::sc_side, dx, dy, -1, s, accel);
}
break;
default:
// [RH] It wasn't a scroller after all, so restore the special.
l->special = special;
break;
}
}
}
//-----------------------------------------------------------------------------
//
// Modify a wall scroller
//
//-----------------------------------------------------------------------------
void SetWallScroller (int id, int sidechoice, double dx, double dy, EScrollPos Where)
{
Where = Where & scw_all;
if (Where == 0) return;
if (dx == 0 && dy == 0)
{
// Special case: Remove the scroller, because the deltas are both 0.
TThinkerIterator<DScroller> iterator (STAT_SCROLLER);
DScroller *scroller;
while ( (scroller = iterator.Next ()) )
{
int wallnum = scroller->GetWallNum ();
if (wallnum >= 0 && tagManager.LineHasID(level.sides[wallnum].linedef, id) &&
level.sides[wallnum].linedef->sidedef[sidechoice]->Index() == wallnum &&
Where == scroller->GetScrollParts())
{
scroller->Destroy ();
}
}
}
else
{
// Find scrollers already attached to the matching walls, and change
// their rates.
TArray<FThinkerCollection> Collection;
{
TThinkerIterator<DScroller> iterator (STAT_SCROLLER);
FThinkerCollection collect;
while ( (collect.Obj = iterator.Next ()) )
{
if ((collect.RefNum = ((DScroller *)collect.Obj)->GetWallNum ()) != -1 &&
tagManager.LineHasID(level.sides[collect.RefNum].linedef, id) &&
level.sides[collect.RefNum].linedef->sidedef[sidechoice]->Index() == collect.RefNum &&
Where == ((DScroller *)collect.Obj)->GetScrollParts())
{
((DScroller *)collect.Obj)->SetRate (dx, dy);
Collection.Push (collect);
}
}
}
size_t numcollected = Collection.Size ();
int linenum;
// Now create scrollers for any walls that don't already have them.
FLineIdIterator itr(id);
while ((linenum = itr.Next()) >= 0)
{
if (level.lines[linenum].sidedef[sidechoice] != NULL)
{
int sidenum = level.lines[linenum].sidedef[sidechoice]->Index();
unsigned int i;
for (i = 0; i < numcollected; i++)
{
if (Collection[i].RefNum == sidenum)
break;
}
if (i == numcollected)
{
Create<DScroller> (EScroll::sc_side, dx, dy, -1, sidenum, 0, Where);
}
}
}
}
}
void SetScroller (int tag, EScroll type, double dx, double dy)
{
TThinkerIterator<DScroller> iterator (STAT_SCROLLER);
DScroller *scroller;
int i;
// Check if there is already a scroller for this tag
// If at least one sector with this tag is scrolling, then they all are.
// If the deltas are both 0, we don't remove the scroller, because a
// displacement/accelerative scroller might have been set up, and there's
// no way to create one after the level is fully loaded.
i = 0;
while ( (scroller = iterator.Next ()) )
{
if (scroller->IsType (type))
{
if (tagManager.SectorHasTag(scroller->GetAffectee (), tag))
{
i++;
scroller->SetRate (dx, dy);
}
}
}
if (i > 0 || (dx == 0 && dy == 0))
{
return;
}
// Need to create scrollers for the sector(s)
FSectorTagIterator itr(tag);
while ((i = itr.Next()) >= 0)
{
Create<DScroller> (type, dx, dy, -1, i, 0);
}
}
void P_CreateScroller(EScroll type, double dx, double dy, int control, int affectee, int accel, EScrollPos scrollpos)
{
Create<DScroller>(type, dx, dy, control, affectee, accel, scrollpos);
}
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