Kart-Public/src/p_slopes.c
Sryder 683ebec120 Rotate All MD2s to match their standing slopes
Needs to be tested in gravity flip
Also flips the normal on linedef based slopes so that it's facing the correct direction
Also makes it so slopelaunch doesn't always remove the standingslope (going down some slopes would cause it to be constantly unset and reset)
2018-11-26 00:17:34 +00:00

902 lines
26 KiB
C

// SONIC ROBO BLAST 2
//-----------------------------------------------------------------------------
// Copyright (C) 2004 by Stephen McGranahan
// Copyright (C) 2015-2016 by Sonic Team Junior.
//
// This program is free software distributed under the
// terms of the GNU General Public License, version 2.
// See the 'LICENSE' file for more details.
//-----------------------------------------------------------------------------
/// \file p_slopes.c
/// \brief ZDoom + Eternity Engine Slopes, ported and enhanced by Kalaron
#include "doomdef.h"
#include "r_defs.h"
#include "r_state.h"
#include "m_bbox.h"
#include "z_zone.h"
#include "p_local.h"
#include "p_spec.h"
#include "p_slopes.h"
#include "p_setup.h"
#include "r_main.h"
#include "p_maputl.h"
#include "w_wad.h"
#ifdef ESLOPE
static pslope_t *slopelist = NULL;
static UINT16 slopecount = 0;
// Calculate line normal
void P_CalculateSlopeNormal(pslope_t *slope) {
slope->normal.z = FINECOSINE(slope->zangle>>ANGLETOFINESHIFT);
slope->normal.x = -FixedMul(FINESINE(slope->zangle>>ANGLETOFINESHIFT), -slope->d.x);
slope->normal.y = -FixedMul(FINESINE(slope->zangle>>ANGLETOFINESHIFT), -slope->d.y);
}
// With a vertex slope that has its vertices set, configure relevant slope info
static void P_ReconfigureVertexSlope(pslope_t *slope)
{
vector3_t vec1, vec2;
// Set slope normal
vec1.x = (slope->vertices[1]->x - slope->vertices[0]->x) << FRACBITS;
vec1.y = (slope->vertices[1]->y - slope->vertices[0]->y) << FRACBITS;
vec1.z = (slope->vertices[1]->z - slope->vertices[0]->z) << FRACBITS;
vec2.x = (slope->vertices[2]->x - slope->vertices[0]->x) << FRACBITS;
vec2.y = (slope->vertices[2]->y - slope->vertices[0]->y) << FRACBITS;
vec2.z = (slope->vertices[2]->z - slope->vertices[0]->z) << FRACBITS;
// ugggggggh fixed-point maaaaaaath
slope->extent = max(
max(max(abs(vec1.x), abs(vec1.y)), abs(vec1.z)),
max(max(abs(vec2.x), abs(vec2.y)), abs(vec2.z))
) >> (FRACBITS+5);
vec1.x /= slope->extent;
vec1.y /= slope->extent;
vec1.z /= slope->extent;
vec2.x /= slope->extent;
vec2.y /= slope->extent;
vec2.z /= slope->extent;
FV3_Cross(&vec1, &vec2, &slope->normal);
slope->extent = R_PointToDist2(0, 0, R_PointToDist2(0, 0, slope->normal.x, slope->normal.y), slope->normal.z);
if (slope->normal.z < 0)
slope->extent = -slope->extent;
slope->normal.x = FixedDiv(slope->normal.x, slope->extent);
slope->normal.y = FixedDiv(slope->normal.y, slope->extent);
slope->normal.z = FixedDiv(slope->normal.z, slope->extent);
// Set origin
slope->o.x = slope->vertices[0]->x << FRACBITS;
slope->o.y = slope->vertices[0]->y << FRACBITS;
slope->o.z = slope->vertices[0]->z << FRACBITS;
if (slope->normal.x == 0 && slope->normal.y == 0) { // Set some defaults for a non-sloped "slope"
slope->zangle = slope->xydirection = 0;
slope->zdelta = slope->d.x = slope->d.y = 0;
} else {
// Get direction vector
slope->extent = R_PointToDist2(0, 0, slope->normal.x, slope->normal.y);
slope->d.x = -FixedDiv(slope->normal.x, slope->extent);
slope->d.y = -FixedDiv(slope->normal.y, slope->extent);
// Z delta
slope->zdelta = FixedDiv(slope->extent, slope->normal.z);
// Get angles
slope->xydirection = R_PointToAngle2(0, 0, slope->d.x, slope->d.y)+ANGLE_180;
slope->zangle = InvAngle(R_PointToAngle2(0, 0, FRACUNIT, slope->zdelta));
}
}
// Recalculate dynamic slopes
void P_RunDynamicSlopes(void) {
pslope_t *slope;
for (slope = slopelist; slope; slope = slope->next) {
fixed_t zdelta;
if (slope->flags & SL_NODYNAMIC)
continue;
switch(slope->refpos) {
case 1: // front floor
zdelta = slope->sourceline->backsector->floorheight - slope->sourceline->frontsector->floorheight;
slope->o.z = slope->sourceline->frontsector->floorheight;
break;
case 2: // front ceiling
zdelta = slope->sourceline->backsector->ceilingheight - slope->sourceline->frontsector->ceilingheight;
slope->o.z = slope->sourceline->frontsector->ceilingheight;
break;
case 3: // back floor
zdelta = slope->sourceline->frontsector->floorheight - slope->sourceline->backsector->floorheight;
slope->o.z = slope->sourceline->backsector->floorheight;
break;
case 4: // back ceiling
zdelta = slope->sourceline->frontsector->ceilingheight - slope->sourceline->backsector->ceilingheight;
slope->o.z = slope->sourceline->backsector->ceilingheight;
break;
case 5: // vertices
{
mapthing_t *mt;
size_t i;
INT32 l;
line_t *line;
for (i = 0; i < 3; i++) {
mt = slope->vertices[i];
l = P_FindSpecialLineFromTag(799, mt->angle, -1);
if (l != -1) {
line = &lines[l];
mt->z = line->frontsector->floorheight >> FRACBITS;
}
}
P_ReconfigureVertexSlope(slope);
}
continue; // TODO
default:
I_Error("P_RunDynamicSlopes: slope has invalid type!");
}
if (slope->zdelta != FixedDiv(zdelta, slope->extent)) {
slope->zdelta = FixedDiv(zdelta, slope->extent);
slope->zangle = R_PointToAngle2(0, 0, slope->extent, -zdelta);
P_CalculateSlopeNormal(slope);
}
}
}
//
// P_MakeSlope
//
// Alocates and fill the contents of a slope structure.
//
static pslope_t *P_MakeSlope(const vector3_t *o, const vector2_t *d,
const fixed_t zdelta, UINT8 flags)
{
pslope_t *ret = Z_Malloc(sizeof(pslope_t), PU_LEVEL, NULL);
memset(ret, 0, sizeof(*ret));
ret->o.x = o->x;
ret->o.y = o->y;
ret->o.z = o->z;
ret->d.x = d->x;
ret->d.y = d->y;
ret->zdelta = zdelta;
ret->flags = flags;
// Add to the slope list
ret->next = slopelist;
slopelist = ret;
slopecount++;
ret->id = slopecount;
return ret;
}
//
// P_GetExtent
//
// Returns the distance to the first line within the sector that
// is intersected by a line parallel to the plane normal with the point (ox, oy)
//
static fixed_t P_GetExtent(sector_t *sector, line_t *line)
{
// ZDoom code reference: v3float_t = vertex_t
fixed_t fardist = -FRACUNIT;
size_t i;
// Find furthest vertex from the reference line. It, along with the two ends
// of the line, will define the plane.
for(i = 0; i < sector->linecount; i++)
{
line_t *li = sector->lines[i];
vertex_t tempv;
fixed_t dist;
// Don't compare to the slope line.
if(li == line)
continue;
P_ClosestPointOnLine(li->v1->x, li->v1->y, line, &tempv);
dist = R_PointToDist2(tempv.x, tempv.y, li->v1->x, li->v1->y);
if(dist > fardist)
fardist = dist;
// Okay, maybe do it for v2 as well?
P_ClosestPointOnLine(li->v2->x, li->v2->y, line, &tempv);
dist = R_PointToDist2(tempv.x, tempv.y, li->v2->x, li->v2->y);
if(dist > fardist)
fardist = dist;
}
return fardist;
}
//
// P_SpawnSlope_Line
//
// Creates one or more slopes based on the given line type and front/back
// sectors.
//
void P_SpawnSlope_Line(int linenum)
{
// With dynamic slopes, it's fine to just leave this function as normal,
// because checking to see if a slope had changed will waste more memory than
// if the slope was just updated when called
line_t *line = lines + linenum;
INT16 special = line->special;
pslope_t *fslope = NULL, *cslope = NULL;
vector3_t origin, point;
vector2_t direction;
fixed_t nx, ny, dz, extent;
boolean frontfloor = (special == 700 || special == 702 || special == 703);
boolean backfloor = (special == 710 || special == 712 || special == 713);
boolean frontceil = (special == 701 || special == 702 || special == 713);
boolean backceil = (special == 711 || special == 712 || special == 703);
UINT8 flags = 0; // Slope flags
if (line->flags & ML_NOSONIC)
flags |= SL_NOPHYSICS;
if (!(line->flags & ML_NOTAILS))
flags |= SL_NODYNAMIC;
if (line->flags & ML_NOKNUX)
flags |= SL_ANCHORVERTEX;
if(!frontfloor && !backfloor && !frontceil && !backceil)
{
CONS_Printf("P_SpawnSlope_Line called with non-slope line special.\n");
return;
}
if(!line->frontsector || !line->backsector)
{
CONS_Printf("P_SpawnSlope_Line used on a line without two sides.\n");
return;
}
{
fixed_t len = R_PointToDist2(0, 0, line->dx, line->dy);
nx = FixedDiv(line->dy, len);
ny = -FixedDiv(line->dx, len);
}
origin.x = line->v1->x + (line->v2->x - line->v1->x)/2;
origin.y = line->v1->y + (line->v2->y - line->v1->y)/2;
// For FOF slopes, make a special function to copy to the xy origin & direction relative to the position of the FOF on the map!
if(frontfloor || frontceil)
{
line->frontsector->hasslope = true; // Tell the software renderer that we're sloped
origin.z = line->backsector->floorheight;
direction.x = nx;
direction.y = ny;
extent = P_GetExtent(line->frontsector, line);
if(extent < 0)
{
CONS_Printf("P_SpawnSlope_Line failed to get frontsector extent on line number %i\n", linenum);
return;
}
// reposition the origin according to the extent
point.x = origin.x + FixedMul(direction.x, extent);
point.y = origin.y + FixedMul(direction.y, extent);
direction.x = -direction.x;
direction.y = -direction.y;
// TODO: We take origin and point 's xy values and translate them to the center of an FOF!
if(frontfloor)
{
fixed_t highest, lowest;
size_t l;
point.z = line->frontsector->floorheight; // Startz
dz = FixedDiv(origin.z - point.z, extent); // Destinationz
// In P_SpawnSlopeLine the origin is the centerpoint of the sourcelinedef
fslope = line->frontsector->f_slope =
P_MakeSlope(&point, &direction, dz, flags);
// Set up some shit
fslope->extent = extent;
fslope->refpos = 1;
// Now remember that f_slope IS a vector
// fslope->o = origin 3D point 1 of the vector
// fslope->d = destination 3D point 2 of the vector
// fslope->normal is a 3D line perpendicular to the 3D vector
// Sync the linedata of the line that started this slope
// TODO: Anything special for control sector based slopes later?
fslope->sourceline = line;
// To find the real highz/lowz of a slope, you need to check all the vertexes
// in the slope's sector with P_GetZAt to get the REAL lowz & highz
// Although these slopes are set by floorheights the ANGLE is what a slope is,
// so technically any slope can extend on forever (they are just bound by sectors)
// *You can use sourceline as a reference to see if two slopes really are the same
// Default points for high and low
highest = point.z > origin.z ? point.z : origin.z;
lowest = point.z < origin.z ? point.z : origin.z;
// Now check to see what the REAL high and low points of the slope inside the sector
// TODO: Is this really needed outside of FOFs? -Red
for (l = 0; l < line->frontsector->linecount; l++)
{
fixed_t height = P_GetZAt(line->frontsector->f_slope, line->frontsector->lines[l]->v1->x, line->frontsector->lines[l]->v1->y);
if (height > highest)
highest = height;
if (height < lowest)
lowest = height;
}
// Sets extra clipping data for the frontsector's slope
fslope->highz = highest;
fslope->lowz = lowest;
fslope->zangle = R_PointToAngle2(0, origin.z, extent, point.z);
fslope->xydirection = R_PointToAngle2(origin.x, origin.y, point.x, point.y);
P_CalculateSlopeNormal(fslope);
}
if(frontceil)
{
fixed_t highest, lowest;
size_t l;
origin.z = line->backsector->ceilingheight;
point.z = line->frontsector->ceilingheight;
dz = FixedDiv(origin.z - point.z, extent);
cslope = line->frontsector->c_slope =
P_MakeSlope(&point, &direction, dz, flags);
// Set up some shit
cslope->extent = extent;
cslope->refpos = 2;
// Sync the linedata of the line that started this slope
// TODO: Anything special for control sector based slopes later?
cslope->sourceline = line;
// Remember the way the slope is formed
highest = point.z > origin.z ? point.z : origin.z;
lowest = point.z < origin.z ? point.z : origin.z;
for (l = 0; l < line->frontsector->linecount; l++)
{
fixed_t height = P_GetZAt(line->frontsector->c_slope, line->frontsector->lines[l]->v1->x, line->frontsector->lines[l]->v1->y);
if (height > highest)
highest = height;
if (height < lowest)
lowest = height;
}
// This line special sets extra clipping data for the frontsector's slope
cslope->highz = highest;
cslope->lowz = lowest;
cslope->zangle = R_PointToAngle2(0, origin.z, extent, point.z);
cslope->xydirection = R_PointToAngle2(origin.x, origin.y, point.x, point.y);
P_CalculateSlopeNormal(cslope);
}
}
if(backfloor || backceil)
{
line->backsector->hasslope = true; // Tell the software renderer that we're sloped
origin.z = line->frontsector->floorheight;
// Backsector
direction.x = -nx;
direction.y = -ny;
extent = P_GetExtent(line->backsector, line);
if(extent < 0)
{
CONS_Printf("P_SpawnSlope_Line failed to get backsector extent on line number %i\n", linenum);
return;
}
// reposition the origin according to the extent
point.x = origin.x + FixedMul(direction.x, extent);
point.y = origin.y + FixedMul(direction.y, extent);
direction.x = -direction.x;
direction.y = -direction.y;
if(backfloor)
{
fixed_t highest, lowest;
size_t l;
point.z = line->backsector->floorheight;
dz = FixedDiv(origin.z - point.z, extent);
fslope = line->backsector->f_slope =
P_MakeSlope(&point, &direction, dz, flags);
// Set up some shit
fslope->extent = extent;
fslope->refpos = 3;
// Sync the linedata of the line that started this slope
// TODO: Anything special for control sector based slopes later?
fslope->sourceline = line;
// Remember the way the slope is formed
highest = point.z > origin.z ? point.z : origin.z;
lowest = point.z < origin.z ? point.z : origin.z;
for (l = 0; l < line->backsector->linecount; l++)
{
fixed_t height = P_GetZAt(line->backsector->f_slope, line->backsector->lines[l]->v1->x, line->backsector->lines[l]->v1->y);
if (height > highest)
highest = height;
if (height < lowest)
lowest = height;
}
// This line special sets extra clipping data for the frontsector's slope
fslope->highz = highest;
fslope->lowz = lowest;
fslope->zangle = R_PointToAngle2(0, origin.z, extent, point.z);
fslope->xydirection = R_PointToAngle2(origin.x, origin.y, point.x, point.y);
P_CalculateSlopeNormal(fslope);
}
if(backceil)
{
fixed_t highest, lowest;
size_t l;
origin.z = line->frontsector->ceilingheight;
point.z = line->backsector->ceilingheight;
dz = FixedDiv(origin.z - point.z, extent);
cslope = line->backsector->c_slope =
P_MakeSlope(&point, &direction, dz, flags);
// Set up some shit
cslope->extent = extent;
cslope->refpos = 4;
// Sync the linedata of the line that started this slope
// TODO: Anything special for control sector based slopes later?
cslope->sourceline = line;
// Remember the way the slope is formed
highest = point.z > origin.z ? point.z : origin.z;
lowest = point.z < origin.z ? point.z : origin.z;
for (l = 0; l < line->backsector->linecount; l++)
{
fixed_t height = P_GetZAt(line->backsector->c_slope, line->backsector->lines[l]->v1->x, line->backsector->lines[l]->v1->y);
if (height > highest)
highest = height;
if (height < lowest)
lowest = height;
}
// This line special sets extra clipping data for the backsector's slope
cslope->highz = highest;
cslope->lowz = lowest;
cslope->zangle = R_PointToAngle2(0, origin.z, extent, point.z);
cslope->xydirection = R_PointToAngle2(origin.x, origin.y, point.x, point.y);
P_CalculateSlopeNormal(cslope);
}
}
if(!line->tag)
return;
}
//
// P_NewVertexSlope
//
// Creates a new slope from three vertices with the specified IDs
//
static pslope_t *P_NewVertexSlope(INT16 tag1, INT16 tag2, INT16 tag3, UINT8 flags)
{
size_t i;
mapthing_t *mt = mapthings;
pslope_t *ret = Z_Malloc(sizeof(pslope_t), PU_LEVEL, NULL);
memset(ret, 0, sizeof(*ret));
// Start by setting flags
ret->flags = flags;
// Now set up the vertex list
ret->vertices = Z_Malloc(3*sizeof(mapthing_t), PU_LEVEL, NULL);
memset(ret->vertices, 0, 3*sizeof(mapthing_t));
// And... look for the vertices in question.
for (i = 0; i < nummapthings; i++, mt++) {
if (mt->type != 750) // Haha, I'm hijacking the old Chaos Spawn thingtype for something!
continue;
if (!ret->vertices[0] && mt->angle == tag1)
ret->vertices[0] = mt;
else if (!ret->vertices[1] && mt->angle == tag2)
ret->vertices[1] = mt;
else if (!ret->vertices[2] && mt->angle == tag3)
ret->vertices[2] = mt;
}
// Now set heights for each vertex, because they haven't been set yet
for (i = 0; i < 3; i++) {
mt = ret->vertices[i];
if (!mt) // If a vertex wasn't found, it's game over. There's nothing you can do to recover (except maybe try and kill the slope instead - TODO?)
I_Error("P_NewVertexSlope: Slope vertex %s (for linedef tag %d) not found!", sizeu1(i), tag1);
if (mt->extrainfo)
mt->z = mt->options;
else
mt->z = (R_PointInSubsector(mt->x << FRACBITS, mt->y << FRACBITS)->sector->floorheight >> FRACBITS) + (mt->options >> ZSHIFT);
}
P_ReconfigureVertexSlope(ret);
ret->refpos = 5;
// Add to the slope list
ret->next = slopelist;
slopelist = ret;
slopecount++;
ret->id = slopecount;
return ret;
}
//
// P_CopySectorSlope
//
// Searches through tagged sectors and copies
//
void P_CopySectorSlope(line_t *line)
{
sector_t *fsec = line->frontsector;
int i, special = line->special;
// Check for copy linedefs
for(i = -1; (i = P_FindSectorFromLineTag(line, i)) >= 0;)
{
sector_t *srcsec = sectors + i;
if((special - 719) & 1 && !fsec->f_slope && srcsec->f_slope)
fsec->f_slope = srcsec->f_slope; //P_CopySlope(srcsec->f_slope);
if((special - 719) & 2 && !fsec->c_slope && srcsec->c_slope)
fsec->c_slope = srcsec->c_slope; //P_CopySlope(srcsec->c_slope);
}
fsec->hasslope = true;
line->special = 0; // Linedef was use to set slopes, it finished its job, so now make it a normal linedef
}
//
// P_SlopeById
//
// Looks in the slope list for a slope with a specified ID. Mostly useful for netgame sync
//
pslope_t *P_SlopeById(UINT16 id)
{
pslope_t *ret;
for (ret = slopelist; ret && ret->id != id; ret = ret->next);
return ret;
}
// Reset the dynamic slopes pointer, and read all of the fancy schmancy slopes
void P_ResetDynamicSlopes(void) {
size_t i;
#ifdef ESLOPE_TYPESHIM // Rewrite old specials to new ones, and give a console warning
boolean warned = false;
#endif
slopelist = NULL;
slopecount = 0;
// We'll handle copy slopes later, after all the tag lists have been made.
// Yes, this means copied slopes won't affect things' spawning heights. Too bad for you.
for (i = 0; i < numlines; i++)
{
switch (lines[i].special)
{
#ifdef ESLOPE_TYPESHIM // Rewrite old specials to new ones, and give a console warning
#define WARNME if (!warned) {warned = true; CONS_Alert(CONS_WARNING, "This level uses old slope specials.\nA conversion will be needed before 2.2's release.\n");}
case 386:
case 387:
case 388:
lines[i].special += 700-386;
WARNME
P_SpawnSlope_Line(i);
break;
case 389:
case 390:
case 391:
case 392:
lines[i].special += 710-389;
WARNME
P_SpawnSlope_Line(i);
break;
case 393:
lines[i].special = 703;
WARNME
P_SpawnSlope_Line(i);
break;
case 394:
case 395:
case 396:
lines[i].special += 720-394;
WARNME
break;
#endif
case 700:
case 701:
case 702:
case 703:
case 710:
case 711:
case 712:
case 713:
P_SpawnSlope_Line(i);
break;
case 704:
case 705:
case 714:
case 715:
{
pslope_t **slopetoset;
size_t which = lines[i].special;
UINT8 flags = SL_VERTEXSLOPE;
if (lines[i].flags & ML_NOSONIC)
flags |= SL_NOPHYSICS;
if (!(lines[i].flags & ML_NOTAILS))
flags |= SL_NODYNAMIC;
if (which == 704)
{
slopetoset = &lines[i].frontsector->f_slope;
which = 0;
}
else if (which == 705)
{
slopetoset = &lines[i].frontsector->c_slope;
which = 0;
}
else if (which == 714)
{
slopetoset = &lines[i].backsector->f_slope;
which = 1;
}
else // 715
{
slopetoset = &lines[i].backsector->c_slope;
which = 1;
}
if (lines[i].flags & ML_NOKNUX)
*slopetoset = P_NewVertexSlope(lines[i].tag, sides[lines[i].sidenum[which]].textureoffset >> FRACBITS,
sides[lines[i].sidenum[which]].rowoffset >> FRACBITS, flags);
else
*slopetoset = P_NewVertexSlope(lines[i].tag, lines[i].tag, lines[i].tag, flags);
sides[lines[i].sidenum[which]].sector->hasslope = true;
}
break;
default:
break;
}
}
}
// ============================================================================
//
// Various utilities related to slopes
//
//
// P_GetZAt
//
// Returns the height of the sloped plane at (x, y) as a fixed_t
//
fixed_t P_GetZAt(pslope_t *slope, fixed_t x, fixed_t y)
{
fixed_t dist = FixedMul(x - slope->o.x, slope->d.x) +
FixedMul(y - slope->o.y, slope->d.y);
return slope->o.z + FixedMul(dist, slope->zdelta);
}
//
// P_QuantizeMomentumToSlope
//
// When given a vector, rotates it and aligns it to a slope
void P_QuantizeMomentumToSlope(vector3_t *momentum, pslope_t *slope)
{
vector3_t axis; // Fuck you, C90.
if (slope->flags & SL_NOPHYSICS)
return; // No physics, no quantizing.
axis.x = -slope->d.y;
axis.y = slope->d.x;
axis.z = 0;
FV3_Rotate(momentum, &axis, slope->zangle >> ANGLETOFINESHIFT);
}
//
// P_ReverseQuantizeMomentumToSlope
//
// When given a vector, rotates and aligns it to a flat surface (from being relative to a given slope)
void P_ReverseQuantizeMomentumToSlope(vector3_t *momentum, pslope_t *slope)
{
slope->zangle = InvAngle(slope->zangle);
P_QuantizeMomentumToSlope(momentum, slope);
slope->zangle = InvAngle(slope->zangle);
}
// SRB2Kart: This fixes all slope-based jumps for different scales in Kart automatically without map tweaking.
// However, they will always feel off every single time... see for yourself: https://cdn.discordapp.com/attachments/270211093761097728/484924392128774165/kart0181.gif
//#define GROWNEVERMISSES
//
// P_SlopeLaunch
//
// Handles slope ejection for objects
void P_SlopeLaunch(mobj_t *mo)
{
if (!(mo->standingslope->flags & SL_NOPHYSICS)) // If there's physics, time for launching.
{
// Double the pre-rotation Z, then halve the post-rotation Z. This reduces the
// vertical launch given from slopes while increasing the horizontal launch
// given. Good for SRB2's gravity and horizontal speeds.
vector3_t slopemom;
slopemom.x = mo->momx;
slopemom.y = mo->momy;
slopemom.z = mo->momz;
P_QuantizeMomentumToSlope(&slopemom, mo->standingslope);
#ifdef GROWNEVERMISSES
{
const fixed_t xyscale = mapheaderinfo[gamemap-1]->mobj_scale + (mapheaderinfo[gamemap-1]->mobj_scale - mo->scale);
const fixed_t zscale = mapheaderinfo[gamemap-1]->mobj_scale + (mapheaderinfo[gamemap-1]->mobj_scale - mo->scale);
mo->momx = FixedMul(slopemom.x, xyscale);
mo->momy = FixedMul(slopemom.y, xyscale);
mo->momz = FixedMul(slopemom.z, zscale);
}
#else
mo->momx = slopemom.x;
mo->momy = slopemom.y;
mo->momz = slopemom.z;
#endif
//CONS_Printf("Launched off of slope.\n");
mo->standingslope = NULL;
}
}
// Function to help handle landing on slopes
void P_HandleSlopeLanding(mobj_t *thing, pslope_t *slope)
{
vector3_t mom; // Ditto.
if (slope->flags & SL_NOPHYSICS) { // No physics, no need to make anything complicated.
if (P_MobjFlip(thing)*(thing->momz) < 0) { // falling, land on slope
thing->momz = -P_MobjFlip(thing);
thing->standingslope = slope;
}
return;
}
mom.x = thing->momx;
mom.y = thing->momy;
mom.z = thing->momz*2;
P_ReverseQuantizeMomentumToSlope(&mom, slope);
if (P_MobjFlip(thing)*mom.z < 0) { // falling, land on slope
thing->momx = mom.x;
thing->momy = mom.y;
thing->momz = -P_MobjFlip(thing);
thing->standingslope = slope;
}
}
// https://yourlogicalfallacyis.com/slippery-slope
// Handles sliding down slopes, like if they were made of butter :)
void P_ButteredSlope(mobj_t *mo)
{
fixed_t thrust;
if (!mo->standingslope)
return;
if (mo->standingslope->flags & SL_NOPHYSICS)
return; // No physics, no butter.
if (mo->flags & (MF_NOCLIPHEIGHT|MF_NOGRAVITY))
return; // don't slide down slopes if you can't touch them or you're not affected by gravity
if (mo->player) {
if (abs(mo->standingslope->zdelta) < FRACUNIT/4 && !(mo->player->pflags & PF_SPINNING))
return; // Don't slide on non-steep slopes unless spinning
if (abs(mo->standingslope->zdelta) < FRACUNIT/2 && !(mo->player->rmomx || mo->player->rmomy))
return; // Allow the player to stand still on slopes below a certain steepness
}
thrust = FINESINE(mo->standingslope->zangle>>ANGLETOFINESHIFT) * 15 / 16 * (mo->eflags & MFE_VERTICALFLIP ? 1 : -1);
if (mo->player && (mo->player->pflags & PF_SPINNING)) {
fixed_t mult = 0;
if (mo->momx || mo->momy) {
angle_t angle = R_PointToAngle2(0, 0, mo->momx, mo->momy) - mo->standingslope->xydirection;
if (P_MobjFlip(mo) * mo->standingslope->zdelta < 0)
angle ^= ANGLE_180;
mult = FINECOSINE(angle >> ANGLETOFINESHIFT);
}
thrust = FixedMul(thrust, FRACUNIT*2/3 + mult/8);
}
if (mo->momx || mo->momy) // Slightly increase thrust based on the object's speed
thrust = FixedMul(thrust, FRACUNIT+P_AproxDistance(mo->momx, mo->momy)/16);
// This makes it harder to zigzag up steep slopes, as well as allows greater top speed when rolling down
// Let's get the gravity strength for the object...
thrust = FixedMul(thrust, abs(P_GetMobjGravity(mo)));
// ... and its friction against the ground for good measure (divided by original friction to keep behaviour for normal slopes the same).
thrust = FixedMul(thrust, FixedDiv(mo->friction, ORIG_FRICTION));
P_Thrust(mo, mo->standingslope->xydirection, thrust);
}
// EOF
#endif // #ifdef ESLOPE