290 lines
11 KiB
C#

// ClassicalSharp copyright 2014-2016 UnknownShadow200 | Licensed under MIT
using System;
using ClassicalSharp.Physics;
using OpenTK;
namespace ClassicalSharp.Entities {
/// <summary> Entity component that performs collision detection. </summary>
public sealed class PhysicsComponent {
bool useLiquidGravity = false; // used by BlockDefinitions.
bool canLiquidJump = true;
internal bool firstJump, secondJump, jumping;
Entity entity;
Game game;
BlockInfo info;
internal float jumpVel = 0.42f, userJumpVel = 0.42f, serverJumpVel = 0.42f;
internal HacksComponent hacks;
internal CollisionsComponent collisions;
public PhysicsComponent(Game game, Entity entity) {
this.game = game;
this.entity = entity;
info = game.BlockInfo;
}
public void UpdateVelocityState(float xMoving, float zMoving) {
if (!hacks.NoclipSlide && (hacks.Noclip && xMoving == 0 && zMoving == 0))
entity.Velocity = Vector3.Zero;
if (hacks.Flying || hacks.Noclip) {
entity.Velocity.Y = 0; // eliminate the effect of gravity
int dir = (hacks.FlyingUp || jumping) ? 1 : (hacks.FlyingDown ? -1 : 0);
entity.Velocity.Y += 0.12f * dir;
if (hacks.Speeding && hacks.CanSpeed) entity.Velocity.Y += 0.12f * dir;
if (hacks.HalfSpeeding && hacks.CanSpeed) entity.Velocity.Y += 0.06f * dir;
} else if (jumping && entity.TouchesAnyRope() && entity.Velocity.Y > 0.02f) {
entity.Velocity.Y = 0.02f;
}
if (!jumping) {
canLiquidJump = false; return;
}
bool touchWater = entity.TouchesAnyWater();
bool touchLava = entity.TouchesAnyLava();
if (touchWater || touchLava) {
AABB bounds = entity.Bounds;
int feetY = Utils.Floor(bounds.Min.Y), bodyY = feetY + 1;
int headY = Utils.Floor(bounds.Max.Y);
if (bodyY > headY) bodyY = headY;
bounds.Max.Y = bounds.Min.Y = feetY;
bool liquidFeet = entity.TouchesAny(bounds, StandardLiquid);
bounds.Min.Y = Math.Min(bodyY, headY);
bounds.Max.Y = Math.Max(bodyY, headY);
bool liquidRest = entity.TouchesAny(bounds, StandardLiquid);
bool pastJumpPoint = liquidFeet && !liquidRest && (entity.Position.Y % 1 >= 0.4);
if (!pastJumpPoint) {
canLiquidJump = true;
entity.Velocity.Y += 0.04f;
if (hacks.Speeding && hacks.CanSpeed) entity.Velocity.Y += 0.04f;
if (hacks.HalfSpeeding && hacks.CanSpeed) entity.Velocity.Y += 0.02f;
} else if (pastJumpPoint) {
// either A) jump bob in water B) climb up solid on side
if (collisions.HorCollision)
entity.Velocity.Y += touchLava ? 0.30f : 0.13f;
else if (canLiquidJump)
entity.Velocity.Y += touchLava ? 0.20f : 0.10f;
canLiquidJump = false;
}
} else if (useLiquidGravity) {
entity.Velocity.Y += 0.04f;
if (hacks.Speeding && hacks.CanSpeed) entity.Velocity.Y += 0.04f;
if (hacks.HalfSpeeding && hacks.CanSpeed) entity.Velocity.Y += 0.02f;
canLiquidJump = false;
} else if (entity.TouchesAnyRope()) {
entity.Velocity.Y += (hacks.Speeding && hacks.CanSpeed) ? 0.15f : 0.10f;
canLiquidJump = false;
} else if (entity.onGround) {
DoNormalJump();
}
}
public void DoNormalJump() {
entity.Velocity.Y = jumpVel;
if (hacks.Speeding && hacks.CanSpeed) entity.Velocity.Y += jumpVel;
if (hacks.HalfSpeeding && hacks.CanSpeed) entity.Velocity.Y += jumpVel / 2;
canLiquidJump = false;
}
bool StandardLiquid(byte block) {
return info.Collide[block] == CollideType.SwimThrough;
}
static Vector3 waterDrag = new Vector3(0.8f, 0.8f, 0.8f),
lavaDrag = new Vector3(0.5f, 0.5f, 0.5f),
ropeDrag = new Vector3(0.5f, 0.85f, 0.5f),
normalDrag = new Vector3(0.91f, 0.98f, 0.91f),
airDrag = new Vector3(0.6f, 1f, 0.6f);
const float liquidGrav = 0.02f, ropeGrav = 0.034f, normalGrav = 0.08f;
public void PhysicsTick(float xMoving, float zMoving) {
if (hacks.Noclip) entity.onGround = false;
float multiply = GetBaseMultiply(true);
float yMultiply = GetBaseMultiply(hacks.CanSpeed);
float modifier = LowestSpeedModifier();
float yMul = Math.Max(1f, yMultiply / 5) * modifier;
float horMul = multiply * modifier;
if (!(hacks.Flying || hacks.Noclip)) {
if (secondJump) { horMul *= 93f; yMul *= 10f; }
else if (firstJump) { horMul *= 46.5f; yMul *= 7.5f; }
}
if (entity.TouchesAnyWater() && !hacks.Flying && !hacks.Noclip) {
MoveNormal(xMoving, zMoving, 0.02f * horMul, waterDrag, liquidGrav, yMul);
} else if (entity.TouchesAnyLava() && !hacks.Flying && !hacks.Noclip) {
MoveNormal(xMoving, zMoving, 0.02f * horMul, lavaDrag, liquidGrav, yMul);
} else if (entity.TouchesAnyRope() && !hacks.Flying && !hacks.Noclip) {
MoveNormal(xMoving, zMoving, 0.02f * 1.7f, ropeDrag, ropeGrav, yMul);
} else {
float factor = !(hacks.Flying || hacks.Noclip) && entity.onGround ? 0.1f : 0.02f;
float gravity = useLiquidGravity ? liquidGrav : normalGrav;
if (hacks.Flying || hacks.Noclip)
MoveFlying(xMoving, zMoving, factor * horMul, normalDrag, gravity, yMul);
else
MoveNormal(xMoving, zMoving, factor * horMul, normalDrag, gravity, yMul);
if (entity.BlockUnderFeet == Block.Ice && !(hacks.Flying || hacks.Noclip)) {
// limit components to +-0.25f by rescaling vector to [-0.25, 0.25]
if (Math.Abs(entity.Velocity.X) > 0.25f || Math.Abs(entity.Velocity.Z) > 0.25f) {
float scale = Math.Min(
Math.Abs(0.25f / entity.Velocity.X), Math.Abs(0.25f / entity.Velocity.Z));
entity.Velocity.X *= scale;
entity.Velocity.Z *= scale;
}
} else if (entity.onGround || hacks.Flying) {
entity.Velocity = Utils.Mul(entity.Velocity, airDrag); // air drag or ground friction
}
}
if (entity.onGround) { firstJump = false; secondJump = false; }
}
void AdjHeadingVelocity(float x, float z, float factor) {
float dist = (float)Math.Sqrt(x * x + z * z);
if (dist < 0.00001f) return;
if (dist < 1) dist = 1;
float multiply = factor / dist;
entity.Velocity += Utils.RotateY(x * multiply, 0, z * multiply, entity.HeadYawRadians);
}
void MoveFlying(float xMoving, float zMoving, float factor, Vector3 drag, float gravity, float yMul) {
AdjHeadingVelocity(zMoving, xMoving, factor);
float yVel = (float)Math.Sqrt(entity.Velocity.X * entity.Velocity.X + entity.Velocity.Z * entity.Velocity.Z);
// make horizontal speed the same as vertical speed.
if ((xMoving != 0 || zMoving != 0) && yVel > 0.001f) {
entity.Velocity.Y = 0;
yMul = 1;
if (hacks.FlyingUp || jumping) entity.Velocity.Y += yVel;
if (hacks.FlyingDown) entity.Velocity.Y -= yVel;
}
Move(drag, gravity, yMul);
}
void MoveNormal(float xMoving, float zMoving, float factor, Vector3 drag, float gravity, float yMul) {
AdjHeadingVelocity(zMoving, xMoving, factor);
Move(drag, gravity, yMul);
}
void Move(Vector3 drag, float gravity, float yMul) {
entity.Velocity.Y *= yMul;
if (!hacks.Noclip)
collisions.MoveAndWallSlide();
entity.Position += entity.Velocity;
entity.Velocity.Y /= yMul;
entity.Velocity = Utils.Mul(entity.Velocity, drag);
entity.Velocity.Y -= gravity;
}
float GetBaseMultiply(bool canSpeed) {
float multiply = 0;
float speed = (hacks.Flying || hacks.Noclip) ? 8 : 1;
if (hacks.Speeding && canSpeed) multiply += speed * hacks.SpeedMultiplier;
if (hacks.HalfSpeeding && canSpeed) multiply += speed * hacks.SpeedMultiplier / 2;
if (multiply == 0) multiply = speed;
return hacks.CanSpeed ? multiply : Math.Min(multiply, hacks.MaxSpeedMultiplier);
}
const float inf = float.PositiveInfinity;
float LowestSpeedModifier() {
AABB bounds = entity.Bounds;
useLiquidGravity = false;
float baseModifier = LowestModifier(bounds, false);
bounds.Min.Y -= 0.5f/16f; // also check block standing on
float solidModifier = LowestModifier(bounds, true);
if (baseModifier == inf && solidModifier == inf) return 1;
return baseModifier == inf ? solidModifier : baseModifier;
}
float LowestModifier(AABB bounds, bool checkSolid) {
Vector3I bbMin = Vector3I.Floor(bounds.Min);
Vector3I bbMax = Vector3I.Floor(bounds.Max);
float modifier = inf;
for (int y = bbMin.Y; y <= bbMax.Y; y++)
for (int z = bbMin.Z; z <= bbMax.Z; z++)
for (int x = bbMin.X; x <= bbMax.X; x++)
{
byte block = game.World.SafeGetBlock(x, y, z);
if (block == 0) continue;
CollideType type = info.Collide[block];
if (type == CollideType.Solid && !checkSolid)
continue;
Vector3 min = new Vector3(x, y, z) + info.MinBB[block];
Vector3 max = new Vector3(x, y, z) + info.MaxBB[block];
AABB blockBB = new AABB(min, max);
if (!blockBB.Intersects(bounds)) continue;
modifier = Math.Min(modifier, info.SpeedMultiplier[block]);
if (!info.IsLiquid(block) && type == CollideType.SwimThrough)
useLiquidGravity = true;
}
return modifier;
}
/// <summary> Calculates the jump velocity required such that when a client presses
/// the jump binding they will be able to jump up to the given height. </summary>
internal void CalculateJumpVelocity(bool userVel, float jumpHeight) {
jumpVel = 0;
if (jumpHeight >= 256) jumpVel = 10.0f;
if (jumpHeight >= 512) jumpVel = 16.5f;
if (jumpHeight >= 768) jumpVel = 22.5f;
while (GetMaxHeight(jumpVel) <= jumpHeight)
jumpVel += 0.001f;
if (userVel) userJumpVel = jumpVel;
}
public static double GetMaxHeight(float u) {
// equation below comes from solving diff(x(t, u))= 0
// We only work in discrete timesteps, so test both rounded up and down.
double t = 49.49831645 * Math.Log(0.247483075 * u + 0.9899323);
return Math.Max(YPosAt((int)t, u), YPosAt((int)t + 1, u));
}
static double YPosAt(int t, float u) {
// v(t, u) = (4 + u) * (0.98^t) - 4, where u = initial velocity
// x(t, u) = Σv(t, u) from 0 to t (since we work in discrete timesteps)
// plugging into Wolfram Alpha gives 1 equation as
// (0.98^t) * (-49u - 196) - 4t + 50u + 196
double a = Math.Exp(-0.0202027 * t); //~0.98^t
return a * (-49 * u - 196) - 4 * t + 50 * u + 196;
}
public void DoEntityPush(ref float xMoving, ref float zMoving) {
if (!game.ClassicMode || hacks.Flying || hacks.Noclip) return;
return;
// TODO: Fix
for (int id = 0; id < 255; id++) {
Entity other = game.Entities[id];
if (other == null) continue;
float dx = other.Position.X - entity.Position.X;
float dy = other.Position.Y - entity.Position.Y;
float dz = other.Position.Z - entity.Position.Z;
float dist = dx * dx + dy * dy + dz * dz;
if (dist < 0.0001f || dist > 0.5f) continue;
double yaw = Math.Atan2(dz, dx) - Math.PI / 2;
Vector3 dir = Utils.GetDirVector(yaw, 0);
Console.WriteLine("Yaw: " + yaw * Utils.Rad2Deg);
Console.WriteLine(dir);
Console.WriteLine(entity.Position);
xMoving = -dir.X;
zMoving = -dir.Z;
}
}
}
}