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sm64pc/src/engine/surface_collision.c

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#include <ultra64.h>
#include "sm64.h"
#include "game/level_update.h"
#include "game/debug.h"
#include "game/camera.h"
#include "game/mario.h"
#include "behavior_script.h"
#include "surface_collision.h"
#include "surface_load.h"
#include "game/object_list_processor.h"
#include "game/room.h"
/**************************************************
* WALLS *
**************************************************/
/**
* Iterate through the list of walls until all walls are checked and
* have given their wall push.
*/
static s32 find_wall_collisions_from_list(struct SurfaceNode *surfaceNode,
struct WallCollisionData *data) {
register f32 offset;
register f32 radius = data->radius;
register struct Surface *surf;
register f32 x = data->x;
register f32 y = data->y + data->offsetY;
register f32 z = data->z;
register f32 px, pz;
register f32 w1, w2, w3;
register f32 y1, y2, y3;
s32 numCols = 0;
// Max collision radius = 200
if (radius > 200.0f) {
radius = 200.0f;
}
// Stay in this loop until out of walls.
while (surfaceNode != NULL) {
surf = surfaceNode->surface;
surfaceNode = surfaceNode->next;
// Exclude a large number of walls immediately to optimize.
if (y < surf->lowerY || y > surf->upperY) {
continue;
}
offset = surf->normal.x * x + surf->normal.y * y + surf->normal.z * z + surf->originOffset;
if (offset < -radius || offset > radius) {
continue;
}
px = x;
pz = z;
//! (Quantum Tunneling) Due to issues with the vertices walls choose and
// the fact they are floating point, certain floating point positions
// along the seam of two walls may collide with neither wall or both walls.
if (surf->flags & SURFACE_FLAG_X_PROJECTION) {
w1 = -surf->vertex1[2];
w2 = -surf->vertex2[2];
w3 = -surf->vertex3[2];
y1 = surf->vertex1[1];
y2 = surf->vertex2[1];
y3 = surf->vertex3[1];
if (surf->normal.x > 0.0f) {
if ((y1 - y) * (w2 - w1) - (w1 - -pz) * (y2 - y1) > 0.0f) {
continue;
}
if ((y2 - y) * (w3 - w2) - (w2 - -pz) * (y3 - y2) > 0.0f) {
continue;
}
if ((y3 - y) * (w1 - w3) - (w3 - -pz) * (y1 - y3) > 0.0f) {
continue;
}
} else {
if ((y1 - y) * (w2 - w1) - (w1 - -pz) * (y2 - y1) < 0.0f) {
continue;
}
if ((y2 - y) * (w3 - w2) - (w2 - -pz) * (y3 - y2) < 0.0f) {
continue;
}
if ((y3 - y) * (w1 - w3) - (w3 - -pz) * (y1 - y3) < 0.0f) {
continue;
}
}
} else {
w1 = surf->vertex1[0];
w2 = surf->vertex2[0];
w3 = surf->vertex3[0];
y1 = surf->vertex1[1];
y2 = surf->vertex2[1];
y3 = surf->vertex3[1];
if (surf->normal.z > 0.0f) {
if ((y1 - y) * (w2 - w1) - (w1 - px) * (y2 - y1) > 0.0f) {
continue;
}
if ((y2 - y) * (w3 - w2) - (w2 - px) * (y3 - y2) > 0.0f) {
continue;
}
if ((y3 - y) * (w1 - w3) - (w3 - px) * (y1 - y3) > 0.0f) {
continue;
}
} else {
if ((y1 - y) * (w2 - w1) - (w1 - px) * (y2 - y1) < 0.0f) {
continue;
}
if ((y2 - y) * (w3 - w2) - (w2 - px) * (y3 - y2) < 0.0f) {
continue;
}
if ((y3 - y) * (w1 - w3) - (w3 - px) * (y1 - y3) < 0.0f) {
continue;
}
}
}
// Determine if checking for the camera or not.
if (gCheckingSurfaceCollisionsForCamera) {
if (surf->flags & SURFACE_FLAG_NO_CAM_COLLISION) {
continue;
}
} else {
// Ignore camera only surfaces.
if (surf->type == SURFACE_CAMERA_BOUNDARY) {
continue;
}
// If an object can pass through a vanish cap wall, pass through.
if (surf->type == SURFACE_VANISH_CAP_WALLS) {
// If an object can pass through a vanish cap wall, pass through.
if (gCurrentObject != NULL
&& (gCurrentObject->activeFlags & ACTIVE_FLAG_MOVE_THROUGH_GRATE)) {
continue;
}
// If Mario has a vanish cap, pass through the vanish cap wall.
if (gCurrentObject != NULL && gCurrentObject == gMarioObject
&& (gMarioState->flags & MARIO_VANISH_CAP)) {
continue;
}
}
}
//! (Wall Overlaps) Because this doesn't update the x and z local variables,
// multiple walls can push mario more than is required.
data->x += surf->normal.x * (radius - offset);
data->z += surf->normal.z * (radius - offset);
//! (Unreferenced Walls) Since this only returns the first four walls,
// this can lead to wall interaction being missed. Typically unreferenced walls
// come from only using one wall, however.
if (data->numWalls < 4) {
data->walls[data->numWalls++] = surf;
}
numCols++;
}
return numCols;
}
/**
* Formats the position and wall search for find_wall_collisions.
*/
s32 f32_find_wall_collision(f32 *xPtr, f32 *yPtr, f32 *zPtr, f32 offsetY, f32 radius) {
struct WallCollisionData collision;
s32 numCollisions = 0;
collision.offsetY = offsetY;
collision.radius = radius;
collision.x = *xPtr;
collision.y = *yPtr;
collision.z = *zPtr;
collision.numWalls = 0;
numCollisions = find_wall_collisions(&collision);
*xPtr = collision.x;
*yPtr = collision.y;
*zPtr = collision.z;
return numCollisions;
}
/**
* Find wall collisions and receive their push.
*/
s32 find_wall_collisions(struct WallCollisionData *colData) {
struct SurfaceNode *node;
s16 cellX, cellZ;
s32 numCollisions = 0;
s16 x = colData->x;
s16 z = colData->z;
colData->numWalls = 0;
if (x <= -LEVEL_BOUNDARY_MAX || x >= LEVEL_BOUNDARY_MAX) {
return numCollisions;
}
if (z <= -LEVEL_BOUNDARY_MAX || z >= LEVEL_BOUNDARY_MAX) {
return numCollisions;
}
// World (level) consists of a 16x16 grid. Find where the collision is on
// the grid (round toward -inf)
cellX = ((x + LEVEL_BOUNDARY_MAX) / CELL_SIZE) & 0x0F;
cellZ = ((z + LEVEL_BOUNDARY_MAX) / CELL_SIZE) & 0x0F;
// Check for surfaces belonging to objects.
node = gDynamicSurfacePartition[cellZ][cellX][SPATIAL_PARTITION_WALLS].next;
numCollisions += find_wall_collisions_from_list(node, colData);
// Check for surfaces that are a part of level geometry.
node = gStaticSurfacePartition[cellZ][cellX][SPATIAL_PARTITION_WALLS].next;
numCollisions += find_wall_collisions_from_list(node, colData);
// Increment the debug tracker.
gNumCalls.wall += 1;
return numCollisions;
}
/**************************************************
* CEILINGS *
**************************************************/
/**
* Iterate through the list of ceilings and find the first ceiling over a given point.
*/
static struct Surface *find_ceil_from_list(struct SurfaceNode *surfaceNode, s32 x, s32 y, s32 z,
f32 *pheight) {
register struct Surface *surf;
register s32 x1, z1, x2, z2, x3, z3;
struct Surface *ceil = NULL;
ceil = NULL;
// Stay in this loop until out of ceilings.
while (surfaceNode != NULL) {
surf = surfaceNode->surface;
surfaceNode = surfaceNode->next;
x1 = surf->vertex1[0];
z1 = surf->vertex1[2];
z2 = surf->vertex2[2];
x2 = surf->vertex2[0];
// Checking if point is in bounds of the triangle laterally.
if ((z1 - z) * (x2 - x1) - (x1 - x) * (z2 - z1) > 0) {
continue;
}
// Slight optimization by checking these later.
x3 = surf->vertex3[0];
z3 = surf->vertex3[2];
if ((z2 - z) * (x3 - x2) - (x2 - x) * (z3 - z2) > 0) {
continue;
}
if ((z3 - z) * (x1 - x3) - (x3 - x) * (z1 - z3) > 0) {
continue;
}
// Determine if checking for the camera or not.
if (gCheckingSurfaceCollisionsForCamera != 0) {
if (surf->flags & SURFACE_FLAG_NO_CAM_COLLISION) {
continue;
}
}
// Ignore camera only surfaces.
else if (surf->type == SURFACE_CAMERA_BOUNDARY) {
continue;
}
{
f32 nx = surf->normal.x;
f32 ny = surf->normal.y;
f32 nz = surf->normal.z;
f32 oo = surf->originOffset;
f32 height;
// If a wall, ignore it. Likely a remnant, should never occur.
if (ny == 0.0f) {
continue;
}
// Find the ceil height at the specific point.
height = -(x * nx + nz * z + oo) / ny;
// Checks for ceiling interaction with a 78 unit buffer.
//! (Exposed Ceilings) Because any point above a ceiling counts
// as interacting with a ceiling, ceilings far below can cause
// "invisible walls" that are really just exposed ceilings.
if (y - (height - -78.0f) > 0.0f) {
continue;
}
*pheight = height;
ceil = surf;
break;
}
}
//! (Surface Cucking) Since only the first ceil is returned and not the lowest,
// lower ceilings can be "cucked" by higher ceilings.
return ceil;
}
/**
* Find the lowest ceiling above a given position and return the height.
*/
f32 find_ceil(f32 posX, f32 posY, f32 posZ, struct Surface **pceil) {
s16 cellZ, cellX;
struct Surface *ceil, *dynamicCeil;
struct SurfaceNode *surfaceList;
f32 height = 20000.0f;
f32 dynamicHeight = 20000.0f;
s16 x, y, z;
//! (Parallel Universes) Because position is casted to an s16, reaching higher
// float locations can return ceilings despite them not existing there.
//(Dynamic ceilings will unload due to the range.)
x = (s16) posX;
y = (s16) posY;
z = (s16) posZ;
*pceil = NULL;
if (x <= -LEVEL_BOUNDARY_MAX || x >= LEVEL_BOUNDARY_MAX) {
return height;
}
if (z <= -LEVEL_BOUNDARY_MAX || z >= LEVEL_BOUNDARY_MAX) {
return height;
}
// Each level is split into cells to limit load, find the appropriate cell.
cellX = ((x + LEVEL_BOUNDARY_MAX) / CELL_SIZE) & 0xF;
cellZ = ((z + LEVEL_BOUNDARY_MAX) / CELL_SIZE) & 0xF;
// Check for surfaces belonging to objects.
surfaceList = gDynamicSurfacePartition[cellZ][cellX][SPATIAL_PARTITION_CEILS].next;
dynamicCeil = find_ceil_from_list(surfaceList, x, y, z, &dynamicHeight);
// Check for surfaces that are a part of level geometry.
surfaceList = gStaticSurfacePartition[cellZ][cellX][SPATIAL_PARTITION_CEILS].next;
ceil = find_ceil_from_list(surfaceList, x, y, z, &height);
if (dynamicHeight < height) {
ceil = dynamicCeil;
height = dynamicHeight;
}
*pceil = ceil;
// Increment the debug tracker.
gNumCalls.ceil += 1;
return height;
}
/**************************************************
* FLOORS *
**************************************************/
/**
* Find the height of the highest floor below an object.
*/
static f32 unused_obj_find_floor_height(struct Object *obj) {
struct Surface *floor;
f32 floorHeight = find_floor(obj->oPosX, obj->oPosY, obj->oPosZ, &floor);
return floorHeight;
}
/**
* Basically a local variable that passes through floor geo info.
*/
struct FloorGeometry sFloorGeo;
static u8 unused8038BE50[0x40];
/**
* Return the floor height underneath (xPos, yPos, zPos) and populate `floorGeo`
* with data about the floor's normal vector and origin offset. Also update
* sFloorGeo.
*/
f32 find_floor_height_and_data(f32 xPos, f32 yPos, f32 zPos, struct FloorGeometry **floorGeo) {
struct Surface *floor;
f32 floorHeight = find_floor(xPos, yPos, zPos, &floor);
*floorGeo = NULL;
if (floor != NULL) {
sFloorGeo.normalX = floor->normal.x;
sFloorGeo.normalY = floor->normal.y;
sFloorGeo.normalZ = floor->normal.z;
sFloorGeo.originOffset = floor->originOffset;
*floorGeo = &sFloorGeo;
}
return floorHeight;
}
/**
* Iterate through the list of floors and find the first floor under a given point.
*/
static struct Surface *find_floor_from_list(struct SurfaceNode *surfaceNode, s32 x, s32 y, s32 z,
f32 *pheight) {
register struct Surface *surf;
register s32 x1, z1, x2, z2, x3, z3;
f32 nx, ny, nz;
f32 oo;
f32 height;
struct Surface *floor = NULL;
// Iterate through the list of floors until there are no more floors.
while (surfaceNode != NULL) {
surf = surfaceNode->surface;
surfaceNode = surfaceNode->next;
x1 = surf->vertex1[0];
z1 = surf->vertex1[2];
x2 = surf->vertex2[0];
z2 = surf->vertex2[2];
// Check that the point is within the triangle bounds.
if ((z1 - z) * (x2 - x1) - (x1 - x) * (z2 - z1) < 0) {
continue;
}
// To slightly save on computation time, set this later.
x3 = surf->vertex3[0];
z3 = surf->vertex3[2];
if ((z2 - z) * (x3 - x2) - (x2 - x) * (z3 - z2) < 0) {
continue;
}
if ((z3 - z) * (x1 - x3) - (x3 - x) * (z1 - z3) < 0) {
continue;
}
// Determine if we are checking for the camera or not.
if (gCheckingSurfaceCollisionsForCamera != 0) {
if (surf->flags & SURFACE_FLAG_NO_CAM_COLLISION) {
continue;
}
}
// If we are not checking for the camera, ignore camera only floors.
else if (surf->type == SURFACE_CAMERA_BOUNDARY) {
continue;
}
nx = surf->normal.x;
ny = surf->normal.y;
nz = surf->normal.z;
oo = surf->originOffset;
// If a wall, ignore it. Likely a remnant, should never occur.
if (ny == 0.0f) {
continue;
}
// Find the height of the floor at a given location.
height = -(x * nx + nz * z + oo) / ny;
// Checks for floor interaction with a 78 unit buffer.
if (y - (height + -78.0f) < 0.0f) {
continue;
}
*pheight = height;
floor = surf;
break;
}
//! (Surface Cucking) Since only the first floor is returned and not the highest,
// higher floors can be "cucked" by lower floors.
return floor;
}
/**
* Find the height of the highest floor below a point.
*/
f32 find_floor_height(f32 x, f32 y, f32 z) {
struct Surface *floor;
f32 floorHeight = find_floor(x, y, z, &floor);
return floorHeight;
}
/**
* Find the highest dynamic floor under a given position. Perhaps originally static and
* and dynamic floors were checked separately.
*/
static f32 unused_find_dynamic_floor(f32 xPos, f32 yPos, f32 zPos, struct Surface **pfloor) {
struct SurfaceNode *surfaceList;
struct Surface *floor;
f32 floorHeight = -11000.0f;
// Would normally cause PUs, but dynamic floors unload at that range.
s16 x = (s16) xPos;
s16 y = (s16) yPos;
s16 z = (s16) zPos;
// Each level is split into cells to limit load, find the appropriate cell.
s16 cellX = ((x + LEVEL_BOUNDARY_MAX) / CELL_SIZE) & 0x0F;
s16 cellZ = ((z + LEVEL_BOUNDARY_MAX) / CELL_SIZE) & 0x0F;
surfaceList = gDynamicSurfacePartition[cellZ][cellX][SPATIAL_PARTITION_FLOORS].next;
floor = find_floor_from_list(surfaceList, x, y, z, &floorHeight);
*pfloor = floor;
return floorHeight;
}
/**
* Find the highest floor under a given position and return the height.
*/
f32 find_floor(f32 xPos, f32 yPos, f32 zPos, struct Surface **pfloor) {
s16 cellZ, cellX;
struct Surface *floor, *dynamicFloor;
struct SurfaceNode *surfaceList;
f32 height = -11000.0f;
f32 dynamicHeight = -11000.0f;
//! (Parallel Universes) Because position is casted to an s16, reaching higher
// float locations can return floors despite them not existing there.
//(Dynamic floors will unload due to the range.)
s16 x = (s16) xPos;
s16 y = (s16) yPos;
s16 z = (s16) zPos;
*pfloor = NULL;
if (x <= -LEVEL_BOUNDARY_MAX || x >= LEVEL_BOUNDARY_MAX) {
return height;
}
if (z <= -LEVEL_BOUNDARY_MAX || z >= LEVEL_BOUNDARY_MAX) {
return height;
}
// Each level is split into cells to limit load, find the appropriate cell.
cellX = ((x + LEVEL_BOUNDARY_MAX) / CELL_SIZE) & 0xF;
cellZ = ((z + LEVEL_BOUNDARY_MAX) / CELL_SIZE) & 0xF;
// Check for surfaces belonging to objects.
surfaceList = gDynamicSurfacePartition[cellZ][cellX][SPATIAL_PARTITION_FLOORS].next;
dynamicFloor = find_floor_from_list(surfaceList, x, y, z, &dynamicHeight);
// Check for surfaces that are a part of level geometry.
surfaceList = gStaticSurfacePartition[cellZ][cellX][SPATIAL_PARTITION_FLOORS].next;
floor = find_floor_from_list(surfaceList, x, y, z, &height);
// To prevent the Merry-Go-Round room from loading when Mario passes above the hole that leads
// there, SURFACE_INTANGIBLE is used. This prevent the wrong room from loading, but can also allow
// Mario to pass through.
if (!gFindFloorIncludeSurfaceIntangible) {
//! (BBH Crash) Most NULL checking is done by checking the height of the floor returned
// instead of checking directly for a NULL floor. If this check returns a NULL floor
// (happens when there is no floor under the SURFACE_INTANGIBLE floor) but returns the height
// of the SURFACE_INTANGIBLE floor instead of the typical -11000 returned for a NULL floor.
if (floor != NULL && floor->type == SURFACE_INTANGIBLE) {
floor = find_floor_from_list(surfaceList, x, (s32)(height - 200.0f), z, &height);
}
} else {
// To prevent accidentally leaving the floor tangible, stop checking for it.
gFindFloorIncludeSurfaceIntangible = FALSE;
}
// If a floor was missed, increment the debug counter.
if (floor == NULL) {
gNumFindFloorMisses += 1;
}
if (dynamicHeight > height) {
floor = dynamicFloor;
height = dynamicHeight;
}
*pfloor = floor;
// Increment the debug tracker.
gNumCalls.floor += 1;
return height;
}
/**************************************************
* ENVIRONMENTAL BOXES *
**************************************************/
/**
* Finds the height of water at a given location.
*/
f32 find_water_level(f32 x, f32 z) {
s32 i;
s32 numRegions;
s16 val;
f32 loX, hiX, loZ, hiZ;
f32 waterLevel = -11000.0f;
s16 *p = gEnvironmentRegions;
if (p != NULL) {
numRegions = *p++;
for (i = 0; i < numRegions; i++) {
val = *p++;
loX = *p++;
loZ = *p++;
hiX = *p++;
hiZ = *p++;
// If the location is within a water box and it is a water box.
// Water is less than 50 val only, while above is gas and such.
if (loX < x && x < hiX && loZ < z && z < hiZ && val < 50) {
// Set the water height. Since this breaks, only return the first height.
waterLevel = *p;
break;
}
p++;
}
}
return waterLevel;
}
/**
* Finds the height of the poison gas (used only in HMC) at a given location.
*/
f32 find_poison_gas_level(f32 x, f32 z) {
s32 i;
s32 numRegions;
UNUSED s32 unused;
s16 val;
f32 loX, hiX, loZ, hiZ;
f32 gasLevel = -11000.0f;
s16 *p = gEnvironmentRegions;
if (p != NULL) {
numRegions = *p++;
for (i = 0; i < numRegions; i++) {
val = *p;
if (val >= 50) {
loX = *(p + 1);
loZ = *(p + 2);
hiX = *(p + 3);
hiZ = *(p + 4);
// If the location is within a gas's box and it is a gas box.
// Gas has a value of 50, 60, etc.
if (loX < x && x < hiX && loZ < z && z < hiZ && val % 10 == 0) {
// Set the gas height. Since this breaks, only return the first height.
gasLevel = *(p + 5);
break;
}
}
p += 6;
}
}
return gasLevel;
}
/**************************************************
* DEBUG *
**************************************************/
/**
* Finds the length of a surface list for debug purposes.
*/
static s32 surface_list_length(struct SurfaceNode *list) {
s32 count = 0;
while (list != NULL) {
list = list->next;
count++;
}
return count;
}
/**
* Print the area,number of walls, how many times they were called,
* and some allocation information.
*/
void debug_surface_list_info(f32 xPos, f32 zPos) {
struct SurfaceNode *list;
s32 numFloors = 0;
s32 numWalls = 0;
s32 numCeils = 0;
s32 cellX = (xPos + LEVEL_BOUNDARY_MAX) / CELL_SIZE;
s32 cellZ = (zPos + LEVEL_BOUNDARY_MAX) / CELL_SIZE;
list = gStaticSurfacePartition[cellZ & 0x0F][cellX & 0x0F][SPATIAL_PARTITION_FLOORS].next;
numFloors += surface_list_length(list);
list = gDynamicSurfacePartition[cellZ & 0x0F][cellX & 0x0F][SPATIAL_PARTITION_FLOORS].next;
numFloors += surface_list_length(list);
list = gStaticSurfacePartition[cellZ & 0x0F][cellX & 0x0F][SPATIAL_PARTITION_WALLS].next;
numWalls += surface_list_length(list);
list = gDynamicSurfacePartition[cellZ & 0x0F][cellX & 0x0F][SPATIAL_PARTITION_WALLS].next;
numWalls += surface_list_length(list);
list = gStaticSurfacePartition[cellZ & 0x0F][cellX & 0x0F][SPATIAL_PARTITION_CEILS].next;
numCeils += surface_list_length(list);
list = gDynamicSurfacePartition[cellZ & 0x0F][cellX & 0x0F][SPATIAL_PARTITION_CEILS].next;
numCeils += surface_list_length(list);
print_debug_top_down_mapinfo("area %x", cellZ * 16 + cellX);
// Names represent ground, walls, and roofs as found in SMS.
print_debug_top_down_mapinfo("dg %d", numFloors);
print_debug_top_down_mapinfo("dw %d", numWalls);
print_debug_top_down_mapinfo("dr %d", numCeils);
set_text_array_x_y(80, -3);
print_debug_top_down_mapinfo("%d", gNumCalls.floor);
print_debug_top_down_mapinfo("%d", gNumCalls.wall);
print_debug_top_down_mapinfo("%d", gNumCalls.ceil);
set_text_array_x_y(-80, 0);
// listal- List Allocated?, statbg- Static Background?, movebg- Moving Background?
print_debug_top_down_mapinfo("listal %d", gSurfaceNodesAllocated);
print_debug_top_down_mapinfo("statbg %d", gNumStaticSurfaces);
print_debug_top_down_mapinfo("movebg %d", gSurfacesAllocated - gNumStaticSurfaces);
gNumCalls.floor = 0;
gNumCalls.ceil = 0;
gNumCalls.wall = 0;
}
/**
* An unused function that finds and interacts with any type of surface.
* Perhaps an original implementation of surfaces before they were more specialized.
*/
static s32 unused_resolve_floor_or_ceil_collisions(s32 checkCeil, f32 *px, f32 *py, f32 *pz, f32 radius,
struct Surface **psurface, f32 *surfaceHeight) {
f32 nx, ny, nz, oo;
f32 x = *px, y = *py, z = *pz;
f32 offset, distance;
*psurface = NULL;
if (checkCeil) {
*surfaceHeight = find_ceil(x, y, z, psurface);
} else {
*surfaceHeight = find_floor(x, y, z, psurface);
}
if (*psurface == NULL) {
return -1;
}
nx = (*psurface)->normal.x;
ny = (*psurface)->normal.y;
nz = (*psurface)->normal.z;
oo = (*psurface)->originOffset;
offset = nx * x + ny * y + nz * z + oo;
distance = offset >= 0 ? offset : -offset;
// Interesting surface interaction that should be surf type independent.
if (distance < radius) {
*px += nx * (radius - offset);
*py += ny * (radius - offset);
*pz += nz * (radius - offset);
return 1;
}
return 0;
}
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