X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Fcollision.cpp;h=0649b5ced8a270e8637e7fdd976f7abecf46f356;hb=3bafbaac49e3d5d1d633b26f60fd4e919399819b;hp=674cf4ed4881224f9a282667120db0c05fa44e2b;hpb=c6fd2986d4261cf742d3bc21e8c12be59ab89f95;p=minetest.git diff --git a/src/collision.cpp b/src/collision.cpp index 674cf4ed4..0649b5ced 100644 --- a/src/collision.cpp +++ b/src/collision.cpp @@ -1,242 +1,616 @@ /* -Minetest-c55 -Copyright (C) 2010 celeron55, Perttu Ahola +Minetest +Copyright (C) 2013 celeron55, Perttu Ahola 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 +it under the terms of the GNU Lesser General Public License as published by +the Free Software Foundation; either version 2.1 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. +GNU Lesser General Public License for more details. -You should have received a copy of the GNU General Public License along +You should have received a copy of the GNU Lesser 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. */ #include "collision.h" +#include #include "mapblock.h" #include "map.h" #include "nodedef.h" #include "gamedef.h" +#ifndef SERVER +#include "client/clientenvironment.h" +#include "client/localplayer.h" +#endif +#include "serverenvironment.h" +#include "server/serveractiveobject.h" +#include "util/timetaker.h" +#include "profiler.h" -collisionMoveResult collisionMoveSimple(Map *map, IGameDef *gamedef, - f32 pos_max_d, const core::aabbox3d &box_0, - f32 dtime, v3f &pos_f, v3f &speed_f) +#ifdef __FAST_MATH__ +#warning "-ffast-math is known to cause bugs in collision code, do not use!" +#endif + +struct NearbyCollisionInfo { + // node + NearbyCollisionInfo(bool is_ul, int bouncy, const v3s16 &pos, + const aabb3f &box) : + is_unloaded(is_ul), + obj(nullptr), + bouncy(bouncy), + position(pos), + box(box) + {} + + // object + NearbyCollisionInfo(ActiveObject *obj, int bouncy, + const aabb3f &box) : + is_unloaded(false), + obj(obj), + bouncy(bouncy), + box(box) + {} + + inline bool isObject() const { return obj != nullptr; } + + bool is_unloaded; + bool is_step_up = false; + ActiveObject *obj; + int bouncy; + v3s16 position; + aabb3f box; +}; + +// Helper functions: +// Truncate floating point numbers to specified number of decimal places +// in order to move all the floating point error to one side of the correct value +static inline f32 truncate(const f32 val, const f32 factor) { - collisionMoveResult result; + return truncf(val * factor) / factor; +} - v3f oldpos_f = pos_f; - v3s16 oldpos_i = floatToInt(oldpos_f, BS); +static inline v3f truncate(const v3f& vec, const f32 factor) +{ + return v3f( + truncate(vec.X, factor), + truncate(vec.Y, factor), + truncate(vec.Z, factor) + ); +} - /* - Calculate new position - */ - pos_f += speed_f * dtime; +// Helper function: +// Checks for collision of a moving aabbox with a static aabbox +// Returns -1 if no collision, 0 if X collision, 1 if Y collision, 2 if Z collision +// The time after which the collision occurs is stored in dtime. +CollisionAxis axisAlignedCollision( + const aabb3f &staticbox, const aabb3f &movingbox, + const v3f &speed, f32 *dtime) +{ + //TimeTaker tt("axisAlignedCollision"); - /* - Collision detection - */ - - // position in nodes - v3s16 pos_i = floatToInt(pos_f, BS); - - /* - Collision uncertainty radius - Make it a bit larger than the maximum distance of movement - */ - f32 d = pos_max_d * 1.1; - // A fairly large value in here makes moving smoother - //f32 d = 0.15*BS; + aabb3f relbox( + (movingbox.MaxEdge.X - movingbox.MinEdge.X) + (staticbox.MaxEdge.X - staticbox.MinEdge.X), // sum of the widths + (movingbox.MaxEdge.Y - movingbox.MinEdge.Y) + (staticbox.MaxEdge.Y - staticbox.MinEdge.Y), + (movingbox.MaxEdge.Z - movingbox.MinEdge.Z) + (staticbox.MaxEdge.Z - staticbox.MinEdge.Z), + std::max(movingbox.MaxEdge.X, staticbox.MaxEdge.X) - std::min(movingbox.MinEdge.X, staticbox.MinEdge.X), //outer bounding 'box' dimensions + std::max(movingbox.MaxEdge.Y, staticbox.MaxEdge.Y) - std::min(movingbox.MinEdge.Y, staticbox.MinEdge.Y), + std::max(movingbox.MaxEdge.Z, staticbox.MaxEdge.Z) - std::min(movingbox.MinEdge.Z, staticbox.MinEdge.Z) + ); - // This should always apply, otherwise there are glitches - assert(d > pos_max_d); - - /* - Calculate collision box - */ - core::aabbox3d box = box_0; - box.MaxEdge += pos_f; - box.MinEdge += pos_f; - core::aabbox3d oldbox = box_0; - oldbox.MaxEdge += oldpos_f; - oldbox.MinEdge += oldpos_f; + const f32 dtime_max = *dtime; + f32 inner_margin; // the distance of clipping recovery + f32 distance; + f32 time; + + + if (speed.Y) { + distance = relbox.MaxEdge.Y - relbox.MinEdge.Y; + *dtime = distance / std::abs(speed.Y); + time = std::max(*dtime, 0.0f); + + if (*dtime <= dtime_max) { + inner_margin = std::max(-0.5f * (staticbox.MaxEdge.Y - staticbox.MinEdge.Y), -2.0f); + + if ((speed.Y > 0 && staticbox.MinEdge.Y - movingbox.MaxEdge.Y > inner_margin) || + (speed.Y < 0 && movingbox.MinEdge.Y - staticbox.MaxEdge.Y > inner_margin)) { + if ( + (std::max(movingbox.MaxEdge.X + speed.X * time, staticbox.MaxEdge.X) + - std::min(movingbox.MinEdge.X + speed.X * time, staticbox.MinEdge.X) + - relbox.MinEdge.X < 0) && + (std::max(movingbox.MaxEdge.Z + speed.Z * time, staticbox.MaxEdge.Z) + - std::min(movingbox.MinEdge.Z + speed.Z * time, staticbox.MinEdge.Z) + - relbox.MinEdge.Z < 0) + ) + return COLLISION_AXIS_Y; + } + } + else { + return COLLISION_AXIS_NONE; + } + } + + // NO else if here + + if (speed.X) { + distance = relbox.MaxEdge.X - relbox.MinEdge.X; + *dtime = distance / std::abs(speed.X); + time = std::max(*dtime, 0.0f); + + if (*dtime <= dtime_max) { + inner_margin = std::max(-0.5f * (staticbox.MaxEdge.X - staticbox.MinEdge.X), -2.0f); + + if ((speed.X > 0 && staticbox.MinEdge.X - movingbox.MaxEdge.X > inner_margin) || + (speed.X < 0 && movingbox.MinEdge.X - staticbox.MaxEdge.X > inner_margin)) { + if ( + (std::max(movingbox.MaxEdge.Y + speed.Y * time, staticbox.MaxEdge.Y) + - std::min(movingbox.MinEdge.Y + speed.Y * time, staticbox.MinEdge.Y) + - relbox.MinEdge.Y < 0) && + (std::max(movingbox.MaxEdge.Z + speed.Z * time, staticbox.MaxEdge.Z) + - std::min(movingbox.MinEdge.Z + speed.Z * time, staticbox.MinEdge.Z) + - relbox.MinEdge.Z < 0) + ) + return COLLISION_AXIS_X; + } + } else { + return COLLISION_AXIS_NONE; + } + } + + // NO else if here + + if (speed.Z) { + distance = relbox.MaxEdge.Z - relbox.MinEdge.Z; + *dtime = distance / std::abs(speed.Z); + time = std::max(*dtime, 0.0f); + + if (*dtime <= dtime_max) { + inner_margin = std::max(-0.5f * (staticbox.MaxEdge.Z - staticbox.MinEdge.Z), -2.0f); + + if ((speed.Z > 0 && staticbox.MinEdge.Z - movingbox.MaxEdge.Z > inner_margin) || + (speed.Z < 0 && movingbox.MinEdge.Z - staticbox.MaxEdge.Z > inner_margin)) { + if ( + (std::max(movingbox.MaxEdge.X + speed.X * time, staticbox.MaxEdge.X) + - std::min(movingbox.MinEdge.X + speed.X * time, staticbox.MinEdge.X) + - relbox.MinEdge.X < 0) && + (std::max(movingbox.MaxEdge.Y + speed.Y * time, staticbox.MaxEdge.Y) + - std::min(movingbox.MinEdge.Y + speed.Y * time, staticbox.MinEdge.Y) + - relbox.MinEdge.Y < 0) + ) + return COLLISION_AXIS_Z; + } + } + } + + return COLLISION_AXIS_NONE; +} + +// Helper function: +// Checks if moving the movingbox up by the given distance would hit a ceiling. +bool wouldCollideWithCeiling( + const std::vector &cinfo, + const aabb3f &movingbox, + f32 y_increase, f32 d) +{ + //TimeTaker tt("wouldCollideWithCeiling"); + + assert(y_increase >= 0); // pre-condition + + for (const auto &it : cinfo) { + const aabb3f &staticbox = it.box; + if ((movingbox.MaxEdge.Y - d <= staticbox.MinEdge.Y) && + (movingbox.MaxEdge.Y + y_increase > staticbox.MinEdge.Y) && + (movingbox.MinEdge.X < staticbox.MaxEdge.X) && + (movingbox.MaxEdge.X > staticbox.MinEdge.X) && + (movingbox.MinEdge.Z < staticbox.MaxEdge.Z) && + (movingbox.MaxEdge.Z > staticbox.MinEdge.Z)) + return true; + } + + return false; +} + +static inline void getNeighborConnectingFace(const v3s16 &p, + const NodeDefManager *nodedef, Map *map, MapNode n, int v, int *neighbors) +{ + MapNode n2 = map->getNode(p); + if (nodedef->nodeboxConnects(n, n2, v)) + *neighbors |= v; +} + +collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef, + f32 pos_max_d, const aabb3f &box_0, + f32 stepheight, f32 dtime, + v3f *pos_f, v3f *speed_f, + v3f accel_f, ActiveObject *self, + bool collideWithObjects) +{ + #define PROFILER_NAME(text) (s_env ? ("Server: " text) : ("Client: " text)) + static bool time_notification_done = false; + Map *map = &env->getMap(); + ServerEnvironment *s_env = dynamic_cast(env); + + ScopeProfiler sp(g_profiler, PROFILER_NAME("collisionMoveSimple()"), SPT_AVG); + + collisionMoveResult result; /* - If the object lies on a walkable node, this is set to true. + Calculate new velocity */ - result.touching_ground = false; - + if (dtime > 0.5f) { + if (!time_notification_done) { + time_notification_done = true; + infostream << "collisionMoveSimple: maximum step interval exceeded," + " lost movement details!"<Y = rangelim(speed_f->Y, -5000, 5000); + speed_f->X = rangelim(speed_f->X, -5000, 5000); + speed_f->Z = rangelim(speed_f->Z, -5000, 5000); + + *speed_f = truncate(*speed_f, 10000.0f); + /* - Go through every node around the object - TODO: Calculate the range of nodes that need to be checked + Collect node boxes in movement range */ - for(s16 y = oldpos_i.Y - 1; y <= oldpos_i.Y + 2; y++) - for(s16 z = oldpos_i.Z - 1; z <= oldpos_i.Z + 1; z++) - for(s16 x = oldpos_i.X - 1; x <= oldpos_i.X + 1; x++) + std::vector cinfo; { - try{ + //TimeTaker tt2("collisionMoveSimple collect boxes"); + ScopeProfiler sp2(g_profiler, PROFILER_NAME("collision collect boxes"), SPT_AVG); + + v3f minpos_f( + MYMIN(pos_f->X, newpos_f.X), + MYMIN(pos_f->Y, newpos_f.Y) + 0.01f * BS, // bias rounding, player often at +/-n.5 + MYMIN(pos_f->Z, newpos_f.Z) + ); + v3f maxpos_f( + MYMAX(pos_f->X, newpos_f.X), + MYMAX(pos_f->Y, newpos_f.Y), + MYMAX(pos_f->Z, newpos_f.Z) + ); + v3s16 min = floatToInt(minpos_f + box_0.MinEdge, BS) - v3s16(1, 1, 1); + v3s16 max = floatToInt(maxpos_f + box_0.MaxEdge, BS) + v3s16(1, 1, 1); + + bool any_position_valid = false; + + v3s16 p; + for (p.X = min.X; p.X <= max.X; p.X++) + for (p.Y = min.Y; p.Y <= max.Y; p.Y++) + for (p.Z = min.Z; p.Z <= max.Z; p.Z++) { + bool is_position_valid; + MapNode n = map->getNode(p, &is_position_valid); + + if (is_position_valid && n.getContent() != CONTENT_IGNORE) { // Object collides into walkable nodes - MapNode n = map->getNode(v3s16(x,y,z)); - if(gamedef->getNodeDefManager()->get(n).walkable == false) + + any_position_valid = true; + const NodeDefManager *nodedef = gamedef->getNodeDefManager(); + const ContentFeatures &f = nodedef->get(n); + + if (!f.walkable) continue; + + // Negative bouncy may have a meaning, but we need +value here. + int n_bouncy_value = abs(itemgroup_get(f.groups, "bouncy")); + + int neighbors = 0; + if (f.drawtype == NDT_NODEBOX && + f.node_box.type == NODEBOX_CONNECTED) { + v3s16 p2 = p; + + p2.Y++; + getNeighborConnectingFace(p2, nodedef, map, n, 1, &neighbors); + + p2 = p; + p2.Y--; + getNeighborConnectingFace(p2, nodedef, map, n, 2, &neighbors); + + p2 = p; + p2.Z--; + getNeighborConnectingFace(p2, nodedef, map, n, 4, &neighbors); + + p2 = p; + p2.X--; + getNeighborConnectingFace(p2, nodedef, map, n, 8, &neighbors); + + p2 = p; + p2.Z++; + getNeighborConnectingFace(p2, nodedef, map, n, 16, &neighbors); + + p2 = p; + p2.X++; + getNeighborConnectingFace(p2, nodedef, map, n, 32, &neighbors); + } + std::vector nodeboxes; + n.getCollisionBoxes(gamedef->ndef(), &nodeboxes, neighbors); + + // Calculate float position only once + v3f posf = intToFloat(p, BS); + for (auto box : nodeboxes) { + box.MinEdge += posf; + box.MaxEdge += posf; + cinfo.emplace_back(false, n_bouncy_value, p, box); + } + } else { + // Collide with unloaded nodes (position invalid) and loaded + // CONTENT_IGNORE nodes (position valid) + aabb3f box = getNodeBox(p, BS); + cinfo.emplace_back(true, 0, p, box); + } + } + + // Do not move if world has not loaded yet, since custom node boxes + // are not available for collision detection. + // This also intentionally occurs in the case of the object being positioned + // solely on loaded CONTENT_IGNORE nodes, no matter where they come from. + if (!any_position_valid) { + *speed_f = v3f(0, 0, 0); + return result; + } + + } // tt2 + + if(collideWithObjects) + { + /* add object boxes to cinfo */ + + std::vector objects; +#ifndef SERVER + ClientEnvironment *c_env = dynamic_cast(env); + if (c_env != 0) { + // Calculate distance by speed, add own extent and 1.5m of tolerance + f32 distance = speed_f->getLength() * dtime + + box_0.getExtent().getLength() + 1.5f * BS; + std::vector clientobjects; + c_env->getActiveObjects(*pos_f, distance, clientobjects); + + for (auto &clientobject : clientobjects) { + // Do collide with everything but itself and the parent CAO + if (!self || (self != clientobject.obj && + self != clientobject.obj->getParent())) { + objects.push_back((ActiveObject*) clientobject.obj); + } + } } - catch(InvalidPositionException &e) + else +#endif { - // Doing nothing here will block the object from - // walking over map borders + if (s_env != NULL) { + // Calculate distance by speed, add own extent and 1.5m of tolerance + f32 distance = speed_f->getLength() * dtime + + box_0.getExtent().getLength() + 1.5f * BS; + + // search for objects which are not us, or we are not its parent + // we directly use the callback to populate the result to prevent + // a useless result loop here + auto include_obj_cb = [self, &objects] (ServerActiveObject *obj) { + if (!obj->isGone() && + (!self || (self != obj && self != obj->getParent()))) { + objects.push_back((ActiveObject *)obj); + } + return false; + }; + + std::vector s_objects; + s_env->getObjectsInsideRadius(s_objects, *pos_f, distance, include_obj_cb); + } } - core::aabbox3d nodebox = getNodeBox(v3s16(x,y,z), BS); - - /* - See if the object is touching ground. + for (std::vector::const_iterator iter = objects.begin(); + iter != objects.end(); ++iter) { + ActiveObject *object = *iter; - Object touches ground if object's minimum Y is near node's - maximum Y and object's X-Z-area overlaps with the node's - X-Z-area. + if (object && object->collideWithObjects()) { + aabb3f object_collisionbox; + if (object->getCollisionBox(&object_collisionbox)) + cinfo.emplace_back(object, 0, object_collisionbox); + } + } +#ifndef SERVER + if (self && c_env) { + LocalPlayer *lplayer = c_env->getLocalPlayer(); + if (lplayer->getParent() == nullptr) { + aabb3f lplayer_collisionbox = lplayer->getCollisionbox(); + v3f lplayer_pos = lplayer->getPosition(); + lplayer_collisionbox.MinEdge += lplayer_pos; + lplayer_collisionbox.MaxEdge += lplayer_pos; + ActiveObject *obj = (ActiveObject*) lplayer->getCAO(); + cinfo.emplace_back(obj, 0, lplayer_collisionbox); + } + } +#endif + } //tt3 - Use 0.15*BS so that it is easier to get on a node. - */ - if( - //fabs(nodebox.MaxEdge.Y-box.MinEdge.Y) < d - fabs(nodebox.MaxEdge.Y-box.MinEdge.Y) < 0.15*BS - && nodebox.MaxEdge.X-d > box.MinEdge.X - && nodebox.MinEdge.X+d < box.MaxEdge.X - && nodebox.MaxEdge.Z-d > box.MinEdge.Z - && nodebox.MinEdge.Z+d < box.MaxEdge.Z - ){ - result.touching_ground = true; + /* + Collision detection + */ + + f32 d = 0.0f; + + int loopcount = 0; + + while(dtime > BS * 1e-10f) { + // Avoid infinite loop + loopcount++; + if (loopcount >= 100) { + warningstream << "collisionMoveSimple: Loop count exceeded, aborting to avoid infiniite loop" << std::endl; + break; } - - // If object doesn't intersect with node, ignore node. - if(box.intersectsWithBox(nodebox) == false) - continue; - + + aabb3f movingbox = box_0; + movingbox.MinEdge += *pos_f; + movingbox.MaxEdge += *pos_f; + + CollisionAxis nearest_collided = COLLISION_AXIS_NONE; + f32 nearest_dtime = dtime; + int nearest_boxindex = -1; + /* - Go through every axis + Go through every nodebox, find nearest collision */ - v3f dirs[3] = { - v3f(0,0,1), // back-front - v3f(0,1,0), // top-bottom - v3f(1,0,0), // right-left - }; - for(u16 i=0; i<3; i++) - { - /* - Calculate values along the axis - */ - f32 nodemax = nodebox.MaxEdge.dotProduct(dirs[i]); - f32 nodemin = nodebox.MinEdge.dotProduct(dirs[i]); - f32 objectmax = box.MaxEdge.dotProduct(dirs[i]); - f32 objectmin = box.MinEdge.dotProduct(dirs[i]); - f32 objectmax_old = oldbox.MaxEdge.dotProduct(dirs[i]); - f32 objectmin_old = oldbox.MinEdge.dotProduct(dirs[i]); - - /* - Check collision for the axis. - Collision happens when object is going through a surface. - */ - bool negative_axis_collides = - (nodemax > objectmin && nodemax <= objectmin_old + d - && speed_f.dotProduct(dirs[i]) < 0); - bool positive_axis_collides = - (nodemin < objectmax && nodemin >= objectmax_old - d - && speed_f.dotProduct(dirs[i]) > 0); - bool main_axis_collides = - negative_axis_collides || positive_axis_collides; - - /* - Check overlap of object and node in other axes - */ - bool other_axes_overlap = true; - for(u16 j=0; j<3; j++) - { - if(j == i) - continue; - f32 nodemax = nodebox.MaxEdge.dotProduct(dirs[j]); - f32 nodemin = nodebox.MinEdge.dotProduct(dirs[j]); - f32 objectmax = box.MaxEdge.dotProduct(dirs[j]); - f32 objectmin = box.MinEdge.dotProduct(dirs[j]); - if(!(nodemax - d > objectmin && nodemin + d < objectmax)) - { - other_axes_overlap = false; - break; + for (u32 boxindex = 0; boxindex < cinfo.size(); boxindex++) { + const NearbyCollisionInfo &box_info = cinfo[boxindex]; + // Ignore if already stepped up this nodebox. + if (box_info.is_step_up) + continue; + + // Find nearest collision of the two boxes (raytracing-like) + f32 dtime_tmp = nearest_dtime; + CollisionAxis collided = axisAlignedCollision(box_info.box, + movingbox, *speed_f, &dtime_tmp); + + if (collided == -1 || dtime_tmp >= nearest_dtime) + continue; + + nearest_dtime = dtime_tmp; + nearest_collided = collided; + nearest_boxindex = boxindex; + } + + if (nearest_collided == COLLISION_AXIS_NONE) { + // No collision with any collision box. + *pos_f += truncate(*speed_f * dtime, 100.0f); + dtime = 0; // Set to 0 to avoid "infinite" loop due to small FP numbers + } else { + // Otherwise, a collision occurred. + NearbyCollisionInfo &nearest_info = cinfo[nearest_boxindex]; + const aabb3f& cbox = nearest_info.box; + + //movingbox except moved to the horizontal position it would be after step up + aabb3f stepbox = movingbox; + stepbox.MinEdge.X += speed_f->X * dtime; + stepbox.MinEdge.Z += speed_f->Z * dtime; + stepbox.MaxEdge.X += speed_f->X * dtime; + stepbox.MaxEdge.Z += speed_f->Z * dtime; + // Check for stairs. + bool step_up = (nearest_collided != COLLISION_AXIS_Y) && // must not be Y direction + (movingbox.MinEdge.Y < cbox.MaxEdge.Y) && + (movingbox.MinEdge.Y + stepheight > cbox.MaxEdge.Y) && + (!wouldCollideWithCeiling(cinfo, stepbox, + cbox.MaxEdge.Y - movingbox.MinEdge.Y, + d)); + + // Get bounce multiplier + float bounce = -(float)nearest_info.bouncy / 100.0f; + + // Move to the point of collision and reduce dtime by nearest_dtime + if (nearest_dtime < 0) { + // Handle negative nearest_dtime + if (!step_up) { + if (nearest_collided == COLLISION_AXIS_X) + pos_f->X += speed_f->X * nearest_dtime; + if (nearest_collided == COLLISION_AXIS_Y) + pos_f->Y += speed_f->Y * nearest_dtime; + if (nearest_collided == COLLISION_AXIS_Z) + pos_f->Z += speed_f->Z * nearest_dtime; } + } else { + *pos_f += truncate(*speed_f * nearest_dtime, 100.0f); + dtime -= nearest_dtime; } - - /* - If this is a collision, revert the pos_f in the main - direction. - */ - if(other_axes_overlap && main_axis_collides) - { - speed_f -= speed_f.dotProduct(dirs[i]) * dirs[i]; - pos_f -= pos_f.dotProduct(dirs[i]) * dirs[i]; - pos_f += oldpos_f.dotProduct(dirs[i]) * dirs[i]; + + bool is_collision = true; + if (nearest_info.is_unloaded) + is_collision = false; + + CollisionInfo info; + if (nearest_info.isObject()) + info.type = COLLISION_OBJECT; + else + info.type = COLLISION_NODE; + + info.node_p = nearest_info.position; + info.object = nearest_info.obj; + info.old_speed = *speed_f; + info.plane = nearest_collided; + + // Set the speed component that caused the collision to zero + if (step_up) { + // Special case: Handle stairs + nearest_info.is_step_up = true; + is_collision = false; + } else if (nearest_collided == COLLISION_AXIS_X) { + if (fabs(speed_f->X) > BS * 3) + speed_f->X *= bounce; + else + speed_f->X = 0; + result.collides = true; + } else if (nearest_collided == COLLISION_AXIS_Y) { + if(fabs(speed_f->Y) > BS * 3) + speed_f->Y *= bounce; + else + speed_f->Y = 0; + result.collides = true; + } else if (nearest_collided == COLLISION_AXIS_Z) { + if (fabs(speed_f->Z) > BS * 3) + speed_f->Z *= bounce; + else + speed_f->Z = 0; + result.collides = true; } - - } - } // xyz - - return result; -} -collisionMoveResult collisionMovePrecise(Map *map, IGameDef *gamedef, - f32 pos_max_d, const core::aabbox3d &box_0, - f32 dtime, v3f &pos_f, v3f &speed_f) -{ - collisionMoveResult final_result; - - // Maximum time increment (for collision detection etc) - // time = distance / speed - f32 dtime_max_increment = pos_max_d / speed_f.getLength(); - - // Maximum time increment is 10ms or lower - if(dtime_max_increment > 0.01) - dtime_max_increment = 0.01; - - // Don't allow overly huge dtime - if(dtime > 2.0) - dtime = 2.0; - - f32 dtime_downcount = dtime; - - u32 loopcount = 0; - do - { - loopcount++; + info.new_speed = *speed_f; + if (info.new_speed.getDistanceFrom(info.old_speed) < 0.1f * BS) + is_collision = false; - f32 dtime_part; - if(dtime_downcount > dtime_max_increment) - { - dtime_part = dtime_max_increment; - dtime_downcount -= dtime_part; - } - else - { - dtime_part = dtime_downcount; - /* - Setting this to 0 (no -=dtime_part) disables an infinite loop - when dtime_part is so small that dtime_downcount -= dtime_part - does nothing - */ - dtime_downcount = 0; + if (is_collision) { + info.axis = nearest_collided; + result.collisions.push_back(info); + } } + } - collisionMoveResult result = collisionMoveSimple(map, gamedef, - pos_max_d, box_0, dtime_part, pos_f, speed_f); + /* + Final touches: Check if standing on ground, step up stairs. + */ + aabb3f box = box_0; + box.MinEdge += *pos_f; + box.MaxEdge += *pos_f; + for (const auto &box_info : cinfo) { + const aabb3f &cbox = box_info.box; - if(result.touching_ground) - final_result.touching_ground = true; - } - while(dtime_downcount > 0.001); - + /* + See if the object is touching ground. - return final_result; -} + Object touches ground if object's minimum Y is near node's + maximum Y and object's X-Z-area overlaps with the node's + X-Z-area. + */ + + if (cbox.MaxEdge.X - d > box.MinEdge.X && cbox.MinEdge.X + d < box.MaxEdge.X && + cbox.MaxEdge.Z - d > box.MinEdge.Z && + cbox.MinEdge.Z + d < box.MaxEdge.Z) { + if (box_info.is_step_up) { + pos_f->Y += cbox.MaxEdge.Y - box.MinEdge.Y; + box = box_0; + box.MinEdge += *pos_f; + box.MaxEdge += *pos_f; + } + if (std::fabs(cbox.MaxEdge.Y - box.MinEdge.Y) < 0.05f) { + result.touching_ground = true; + if (box_info.isObject()) + result.standing_on_object = true; + } + } + } + return result; +}