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Collision: Improve performance by combining 6 vectors into 1 using a …
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…struct
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@ShadowNinja @paramat
ShadowNinja authored and paramat committed Sep 15, 2016
1 parent b885950 commit 6e30dd0
Showing 1 changed file with 58 additions and 64 deletions.
122 changes: 58 additions & 64 deletions src/collision.cpp
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Expand Up @@ -34,6 +34,27 @@ with this program; if not, write to the Free Software Foundation, Inc.,
//#define COLL_ZERO 0.032 // broken unit tests
#define COLL_ZERO 0


struct NearbyCollisionInfo {
NearbyCollisionInfo(bool is_ul, bool is_obj, int bouncy,
const v3s16 &pos, const aabb3f &box) :
is_unloaded(is_ul),
is_step_up(false),
is_object(is_obj),
bouncy(bouncy),
position(pos),
box(box)
{}

bool is_unloaded;
bool is_step_up;
bool is_object;
int bouncy;
v3s16 position;
aabb3f box;
};


// 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
Expand Down Expand Up @@ -160,20 +181,18 @@ int axisAlignedCollision(
// Helper function:
// Checks if moving the movingbox up by the given distance would hit a ceiling.
bool wouldCollideWithCeiling(
const std::vector<aabb3f> &staticboxes,
const std::vector<NearbyCollisionInfo> &cinfo,
const aabb3f &movingbox,
f32 y_increase, f32 d)
{
//TimeTaker tt("wouldCollideWithCeiling");

assert(y_increase >= 0); // pre-condition

for(std::vector<aabb3f>::const_iterator
i = staticboxes.begin();
i != staticboxes.end(); ++i)
{
const aabb3f& staticbox = *i;
if((movingbox.MaxEdge.Y - d <= staticbox.MinEdge.Y) &&
for (std::vector<NearbyCollisionInfo>::const_iterator it = cinfo.begin();
it != cinfo.end(); ++it) {
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) &&
Expand Down Expand Up @@ -234,12 +253,7 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
/*
Collect node boxes in movement range
*/
std::vector<aabb3f> cboxes;
std::vector<bool> is_unloaded;
std::vector<bool> is_step_up;
std::vector<bool> is_object;
std::vector<int> bouncy_values;
std::vector<v3s16> node_positions;
std::vector<NearbyCollisionInfo> cinfo;
{
//TimeTaker tt2("collisionMoveSimple collect boxes");
ScopeProfiler sp(g_profiler, "collisionMoveSimple collect boxes avg", SPT_AVG);
Expand Down Expand Up @@ -310,23 +324,13 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
aabb3f box = *i;
box.MinEdge += v3f(x, y, z)*BS;
box.MaxEdge += v3f(x, y, z)*BS;
cboxes.push_back(box);
is_unloaded.push_back(false);
is_step_up.push_back(false);
bouncy_values.push_back(n_bouncy_value);
node_positions.push_back(p);
is_object.push_back(false);
cinfo.push_back(NearbyCollisionInfo(false,
false, n_bouncy_value, p, box));
}
}
else {
} else {
// Collide with unloaded nodes
aabb3f box = getNodeBox(p, BS);
cboxes.push_back(box);
is_unloaded.push_back(true);
is_step_up.push_back(false);
bouncy_values.push_back(0);
node_positions.push_back(p);
is_object.push_back(false);
cinfo.push_back(NearbyCollisionInfo(true, false, 0, p, box));
}
}

Expand All @@ -344,7 +348,7 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
ScopeProfiler sp(g_profiler, "collisionMoveSimple objects avg", SPT_AVG);
//TimeTaker tt3("collisionMoveSimple collect object boxes");

/* add object boxes to cboxes */
/* add object boxes to cinfo */

std::vector<ActiveObject*> objects;
#ifndef SERVER
Expand Down Expand Up @@ -384,23 +388,12 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
aabb3f object_collisionbox;
if (object->getCollisionBox(&object_collisionbox) &&
object->collideWithObjects()) {
cboxes.push_back(object_collisionbox);
is_unloaded.push_back(false);
is_step_up.push_back(false);
bouncy_values.push_back(0);
node_positions.push_back(v3s16(0,0,0));
is_object.push_back(true);
cinfo.push_back(NearbyCollisionInfo(false, true, 0, v3s16(), object_collisionbox));
}
}
}
} //tt3

assert(cboxes.size() == is_unloaded.size()); // post-condition
assert(cboxes.size() == is_step_up.size()); // post-condition
assert(cboxes.size() == bouncy_values.size()); // post-condition
assert(cboxes.size() == node_positions.size()); // post-condition
assert(cboxes.size() == is_object.size()); // post-condition

/*
Collision detection
*/
Expand Down Expand Up @@ -440,15 +433,16 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
/*
Go through every nodebox, find nearest collision
*/
for (u32 boxindex = 0; boxindex < cboxes.size(); boxindex++) {
for (u32 boxindex = 0; boxindex < cinfo.size(); boxindex++) {
NearbyCollisionInfo box_info = cinfo[boxindex];
// Ignore if already stepped up this nodebox.
if(is_step_up[boxindex])
if (box_info.is_step_up)
continue;

// Find nearest collision of the two boxes (raytracing-like)
f32 dtime_tmp;
int collided = axisAlignedCollision(
cboxes[boxindex], movingbox, *speed_f, d, &dtime_tmp);
int collided = axisAlignedCollision(box_info.box,
movingbox, *speed_f, d, &dtime_tmp);

if (collided == -1 || dtime_tmp >= nearest_dtime)
continue;
Expand All @@ -464,19 +458,19 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
dtime = 0; // Set to 0 to avoid "infinite" loop due to small FP numbers
} else {
// Otherwise, a collision occurred.

const aabb3f& cbox = cboxes[nearest_boxindex];
NearbyCollisionInfo &nearest_info = cinfo[nearest_boxindex];
const aabb3f& cbox = nearest_info.box;
// Check for stairs.
bool step_up = (nearest_collided != 1) && // must not be Y direction
(movingbox.MinEdge.Y < cbox.MaxEdge.Y) &&
(movingbox.MinEdge.Y + stepheight > cbox.MaxEdge.Y) &&
(!wouldCollideWithCeiling(cboxes, movingbox,
(!wouldCollideWithCeiling(cinfo, movingbox,
cbox.MaxEdge.Y - movingbox.MinEdge.Y,
d));

// Get bounce multiplier
bool bouncy = (bouncy_values[nearest_boxindex] >= 1);
float bounce = -(float)bouncy_values[nearest_boxindex] / 100.0;
bool bouncy = (nearest_info.bouncy >= 1);
float bounce = -(float)nearest_info.bouncy / 100.0;

// Move to the point of collision and reduce dtime by nearest_dtime
if (nearest_dtime < 0) {
Expand All @@ -495,39 +489,38 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
}

bool is_collision = true;
if (is_unloaded[nearest_boxindex])
if (nearest_info.is_unloaded)
is_collision = false;

CollisionInfo info;
if (is_object[nearest_boxindex])
if (nearest_info.is_object)
info.type = COLLISION_OBJECT;
else
info.type = COLLISION_NODE;

info.node_p = node_positions[nearest_boxindex];
info.node_p = nearest_info.position;
info.bouncy = bouncy;
info.old_speed = *speed_f;

// Set the speed component that caused the collision to zero
if (step_up) {
// Special case: Handle stairs
is_step_up[nearest_boxindex] = true;
nearest_info.is_step_up = true;
is_collision = false;
} else if(nearest_collided == 0) { // X
} else if (nearest_collided == 0) { // X
if (fabs(speed_f->X) > BS * 3)
speed_f->X *= bounce;
else
speed_f->X = 0;
result.collides = true;
result.collides_xz = true;
}
else if(nearest_collided == 1) { // Y
if (fabs(speed_f->Y) > BS * 3)
} else if (nearest_collided == 1) { // Y
if(fabs(speed_f->Y) > BS * 3)
speed_f->Y *= bounce;
else
speed_f->Y = 0;
result.collides = true;
} else if(nearest_collided == 2) { // Z
} else if (nearest_collided == 2) { // Z
if (fabs(speed_f->Z) > BS * 3)
speed_f->Z *= bounce;
else
Expand All @@ -552,8 +545,9 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
aabb3f box = box_0;
box.MinEdge += *pos_f;
box.MaxEdge += *pos_f;
for (u32 boxindex = 0; boxindex < cboxes.size(); boxindex++) {
const aabb3f& cbox = cboxes[boxindex];
for (u32 boxindex = 0; boxindex < cinfo.size(); boxindex++) {
NearbyCollisionInfo &box_info = cinfo[boxindex];
const aabb3f &cbox = box_info.box;

/*
See if the object is touching ground.
Expand All @@ -567,18 +561,18 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef,
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 (is_step_up[boxindex]) {
pos_f->Y += (cbox.MaxEdge.Y - box.MinEdge.Y);
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 (fabs(cbox.MaxEdge.Y - box.MinEdge.Y) < 0.15 * BS) {
result.touching_ground = true;

if (is_object[boxindex])
if (box_info.is_object)
result.standing_on_object = true;
if (is_unloaded[boxindex])
if (box_info.is_unloaded)
result.standing_on_unloaded = true;
}
}
Expand Down

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