From 6ef7ad09bbed9176d0d15f53b5cb14ef6e18a3b2 Mon Sep 17 00:00:00 2001 From: TheTermos <55103816+TheTermos@users.noreply.github.com> Date: Thu, 14 May 2020 19:28:27 +0200 Subject: [PATCH] Collision detection - #9343 follow-up (#9764) * truncate speed to prevent inf result * code styling * change truncate() input parameters --- src/collision.cpp | 121 ++++++++++++++++++++++++++-------------------- 1 file changed, 69 insertions(+), 52 deletions(-) diff --git a/src/collision.cpp b/src/collision.cpp index 3b5e79a66..06ef820c5 100644 --- a/src/collision.cpp +++ b/src/collision.cpp @@ -66,6 +66,22 @@ struct NearbyCollisionInfo { 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) +{ + return truncf(val * factor) / factor; +} + +static inline v3f truncate(const v3f& vec, const f32 factor) +{ + return v3f( + truncate(vec.X, factor), + truncate(vec.Y, factor), + truncate(vec.Z, factor) + ); +} // Helper function: // Checks for collision of a moving aabbox with a static aabbox @@ -78,70 +94,70 @@ CollisionAxis axisAlignedCollision( //TimeTaker tt("axisAlignedCollision"); 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, + (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) ); const f32 dtime_max = *dtime; - const f32 inner_margin = -1.5f; + f32 inner_margin; // the distance of clipping recovery f32 distance; f32 time; - if (speed.X) { - distance = relbox.MaxEdge.X - relbox.MinEdge.X; - *dtime = distance >= 0 ? std::abs(distance / speed.X) : -std::abs(distance / speed.X); + if (speed.Y) { + distance = relbox.MaxEdge.Y - relbox.MinEdge.Y; + *dtime = distance / std::abs(speed.Y); time = std::max(*dtime, 0.0f); - if (distance > inner_margin) { - if (*dtime <= dtime_max) { - if ((speed.X > 0 && staticbox.MaxEdge.X > movingbox.MaxEdge.X) || - (speed.X < 0 && staticbox.MinEdge.X < movingbox.MinEdge.X)) { - 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) && + 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_X; - } - } else { - return COLLISION_AXIS_NONE; + ) + return COLLISION_AXIS_Y; } } + else { + return COLLISION_AXIS_NONE; + } } // NO else if here - if (speed.Y) { - distance = relbox.MaxEdge.Y - relbox.MinEdge.Y; - - *dtime = distance >= 0 ? std::abs(distance / speed.Y) : -std::abs(distance / speed.Y); + if (speed.X) { + distance = relbox.MaxEdge.X - relbox.MinEdge.X; + *dtime = distance / std::abs(speed.X); time = std::max(*dtime, 0.0f); - if (distance > inner_margin) { - if (*dtime <= dtime_max) { - if ((speed.Y > 0 && staticbox.MaxEdge.Y > movingbox.MaxEdge.Y) || - (speed.Y < 0 && staticbox.MinEdge.Y < movingbox.MinEdge.Y)) { - 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) && + 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_Y; - } - } else { - return COLLISION_AXIS_NONE; + ) + return COLLISION_AXIS_X; } + } else { + return COLLISION_AXIS_NONE; } } @@ -149,24 +165,23 @@ CollisionAxis axisAlignedCollision( if (speed.Z) { distance = relbox.MaxEdge.Z - relbox.MinEdge.Z; - - *dtime = distance >= 0 ? std::abs(distance / speed.Z) : -std::abs(distance / speed.Z); + *dtime = distance / std::abs(speed.Z); time = std::max(*dtime, 0.0f); - if (distance > inner_margin) { - if (*dtime <= dtime_max) { - if ((speed.Z > 0 && staticbox.MaxEdge.Z > movingbox.MaxEdge.Z) || - (speed.Z < 0 && staticbox.MinEdge.Z < movingbox.MinEdge.Z)) { - 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) && + 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_Z; } } } @@ -245,6 +260,8 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef, 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); + /* Collect node boxes in movement range */ @@ -464,7 +481,7 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef, if (nearest_collided == COLLISION_AXIS_NONE) { // No collision with any collision box. - *pos_f += *speed_f * dtime; + *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. @@ -500,7 +517,7 @@ collisionMoveResult collisionMoveSimple(Environment *env, IGameDef *gamedef, pos_f->Z += speed_f->Z * nearest_dtime; } } else { - *pos_f += *speed_f * nearest_dtime; + *pos_f += truncate(*speed_f * nearest_dtime, 100.0f); dtime -= nearest_dtime; }