public override void Update()
{
// Return to normal if not in a hole.
if (!monster.Physics.IsInHole) {
monster.BeginNormalState();
return;
}
// Slip toward the hole's center.
float slipSpeed = 0.2f;
Point2I tileLocation = monster.RoomControl.GetTileLocation(monster.Position);
Vector2F tilePosition = tileLocation * GameSettings.TILE_SIZE;
Vector2F tileCenter = tilePosition + new Vector2F(8, 8);
Rectangle2F holeRect = new Rectangle2F(tilePosition.X + 6, tilePosition.Y + 8, 4, 6);
bool fallInHole = holeRect.Contains(monster.Position);
Vector2F trajectory = tileCenter - monster.Center;
if (trajectory.Length > slipSpeed) {
monster.Physics.Velocity = (tileCenter - monster.Center).Normalized * slipSpeed;
}
else {
fallInHole = true;
monster.Physics.Velocity = Vector2F.Zero;
monster.SetPositionByCenter(tileCenter);
}
if (fallInHole) {
monster.RoomControl.SpawnEntity(new EffectFallingObject(), monster.Center);
AudioSystem.PlaySound(GameData.SOUND_OBJECT_FALL);
monster.Destroy();
}
}
// Returns true if the specified rectangle is colliding with this rectangle.
public bool Colliding(Rectangle2F rect)
{
if (IsEmpty || rect.IsEmpty)
{
return(false);
}
return((rect.Min < Max) &&
(rect.Max > Min));
}
// Returns true if the specified rectangle is inside this rectangle.
public bool Contains(Rectangle2F rect)
{
if (IsEmpty || rect.IsEmpty)
{
return(false);
}
return((rect.Min >= Min) &&
(rect.Max <= Max));
}
// Return whether this and another rectangle are intersecting.
public bool Intersects(Rectangle2F other)
{
if (IsEmpty && other.IsEmpty)
{
return(false);
}
return(!(other.Left - Right >= 0 || other.Top - Bottom >= 0 ||
Left - other.Right >= 0 || Top - other.Bottom >= 0));
}
// Creates a new rectangle that exactly contains two other rectangles.
public static Rectangle2F Union(Rectangle2F r1, Rectangle2F r2)
{
float x1 = Math.Min(r1.Left, r2.Left);
float y1 = Math.Min(r1.Top, r2.Top);
float x2 = Math.Max(r1.Right, r2.Right);
float y2 = Math.Max(r1.Bottom, r2.Bottom);
return(new Rectangle2F(x1, y1, x2 - x1, y2 - y1));
}
//-----------------------------------------------------------------------------
// Static methods
//-----------------------------------------------------------------------------
public static bool Intersecting(CollisionModel model,
Vector2F modelPosition,
Rectangle2F box,
Vector2F boxPosition)
{
Rectangle2F boxTranslated = Rectangle2F.Translate(box, boxPosition - modelPosition);
for (int i = 0; i < model.boxes.Count; i++) {
Rectangle2F modelBox = model.boxes[i];
if (boxTranslated.Intersects(modelBox))
return true;
}
return false;
}
//-----------------------------------------------------------------------------
// Static methods
//-----------------------------------------------------------------------------
// Returns the intersection between two rectangles.
// Returns the Empty rect if there is no intersection.
public static Rectangle2F Intersect(Rectangle2F r1, Rectangle2F r2)
{
float x1 = Math.Max(r1.Left, r2.Left);
float y1 = Math.Max(r1.Top, r2.Top);
float x2 = Math.Min(r1.Right, r2.Right);
float y2 = Math.Min(r1.Bottom, r2.Bottom);
if (x2 > x1 && y2 > y1)
{
return(new Rectangle2F(x1, y1, x2 - x1, y2 - y1));
}
return(Rectangle2F.Zero);
}
public static bool Intersecting(CollisionModel model,
Vector2F modelPosition,
Rectangle2F box,
Vector2F boxPosition)
{
Rectangle2F boxTranslated = Rectangle2F.Translate(box, boxPosition - modelPosition);
for (int i = 0; i < model.boxes.Count; i++)
{
Rectangle2F modelBox = model.boxes[i];
if (boxTranslated.Intersects(modelBox))
{
return(true);
}
}
return(false);
}
private float zVelocity; // Z-Velocity in pixels per frame.
#endregion Fields
#region Constructors
//-----------------------------------------------------------------------------
// Constructors
//-----------------------------------------------------------------------------
// By default, physics are disabled.
public PhysicsComponent(Entity entity)
{
this.isEnabled = false;
this.flags = PhysicsFlags.None;
this.entity = entity;
this.velocity = Vector2F.Zero;
this.zVelocity = 0.0f;
this.gravity = GameSettings.DEFAULT_GRAVITY;
this.maxFallSpeed = GameSettings.DEFAULT_MAX_FALL_SPEED;
this.collisionBox = new Rectangle2F(-4, -10, 8, 9); // TEMPORARY: this is the player collision box.
this.softCollisionBox = new Rectangle2F(-6, -14, 12, 13); // TEMPORARY: this is the player collision box.
this.topTileFlags = TileFlags.None;
this.allTileFlags = TileFlags.None;
this.isColliding = false;
this.autoDodgeDistance = 6;
this.hasLanded = false;
this.collisionInfo = new CollisionInfo[Directions.Count];
for (int i = 0; i < Directions.Count; i++)
collisionInfo[i].Clear();
}
/** <summary> Returns true if the specified rectangle is colliding with this line. </summary> */
public bool Colliding(Rectangle2F rect)
{
if (IsEmpty || rect.IsEmpty)
{
return(false);
}
if (!Bounds.Colliding(rect) && !IsStraight)
{
return(false);
}
if (rect.Contains(End1))
{
return(true);
}
foreach (Line2F l in rect.Lines)
{
if (Colliding(l))
{
return(true);
}
}
return(false);
}
// Creates a copy of a rectangle translated by an amount.
public static Rectangle2F Translate(Rectangle2F r, float x, float y)
{
r.Point.X += x;
r.Point.Y += y;
return(r);
}
// Determine the clipping direction for a collision.
private int GetCollisionClipDirection(Entity entity, object other, Rectangle2F solidBox)
{
Rectangle2F entityBox = entity.Physics.PositionedCollisionBox;
// For moving tiles, use the move direction to determine clip direction.
Tile tile = other as Tile;
if (tile != null && tile.IsMoving) {
if ((solidBox.Center - entityBox.Center).Dot(Directions.ToVector(tile.MoveDirection)) < 0.0f)
return Directions.Reverse(tile.MoveDirection);
}
// Get the nearest direction from the collision intersection to the center of the solid box.
Vector2F intersectionCenter = Rectangle2F.Intersect(entityBox, solidBox).Center;
int clipDirection = Directions.NearestFromVector(solidBox.Center - intersectionCenter);
// If the collision can't be resolved, then try to use a direction on the opposite axis.
CollisionInfoNew testCollision = CreateCollisionInfo(entity, other, solidBox, clipDirection);
if (!testCollision.IsAllowedClipping && !CanResolveCollision(entity, testCollision)) {
int newClipDirection;
int a = 1 - Directions.ToAxis(clipDirection);
if (entityBox.Center[a] < solidBox.Center[a])
newClipDirection = (a == Axes.X ? Directions.Right : Directions.Down);
else
newClipDirection = (a == Axes.X ? Directions.Left : Directions.Up);
testCollision = CreateCollisionInfo(entity, other, solidBox, newClipDirection);
if (testCollision.IsAllowedClipping || CanResolveCollision(entity, testCollision))
clipDirection = newClipDirection;
}
return clipDirection;
}
// Calculate a collision's penetration distance in the given direction.
public float GetClipPenetration(Rectangle2F entityBox, Rectangle2F solidBox, int clipDirection)
{
if (clipDirection == Directions.Right)
return entityBox.Right - solidBox.Left;
else if (clipDirection == Directions.Up)
return solidBox.Bottom - entityBox.Top;
else if (clipDirection == Directions.Left)
return solidBox.Right - entityBox.Left;
else if (clipDirection == Directions.Down)
return entityBox.Bottom - solidBox.Top;
return 0.0f;
}
// Resolve any movement collision between the entity and a solid object
private void ResolveMovementCollision(Entity entity, int axis, object other, Rectangle2F solidBox)
{
// Setup the entity's translated collision box based on which axis we're checking.
Rectangle2F entityBox;
if (axis == Axes.X) {
entityBox = Rectangle2F.Translate(
entity.Physics.CollisionBox, entity.X + entity.Physics.Velocity.X, entity.Y);
}
else {
entityBox = Rectangle2F.Translate(
entity.Physics.CollisionBox, entity.Position + entity.Physics.Velocity);
}
// Check if there actually is a collision.
if (!entityBox.Intersects(solidBox))
return;
// Determine clipping direction.
int clipDirection = -1;
if (axis == Axes.X) {
if (entityBox.Center.X < solidBox.Center.X)
clipDirection = Directions.Right;
else
clipDirection = Directions.Left;
}
else {
if (entityBox.Center.Y < solidBox.Center.Y)
clipDirection = Directions.Down;
else
clipDirection = Directions.Up;
}
// Ignore collision if the entity is already colliding in the opposite
// direction or if the entity is not moving in the clip direction.
if (entity.Physics.ClipCollisionInfo[Directions.Reverse(clipDirection)].IsCollidingAndNotAllowedClipping ||
entity.Physics.Velocity.Dot(Directions.ToVector(clipDirection)) <= 0.0f)
return;
// Ignore collisions that are within the allowed clipping range.
if (IsSafeClipping(entity, 1 - axis, entityBox, other, solidBox))
return;
// Ignore the collision if the entity is clipped into a solid object that shares
// a clip edge with this object and the entity is also moving parallel with that edge.
for (int i = 0; i < 2; i++) {
int dir = Axes.GetOpposite(axis) + (i * 2);
CollisionInfoNew checkCollision = entity.Physics.ClipCollisionInfo[dir];
if (checkCollision.IsColliding && AreEdgesAligned(
checkCollision.CollisionBox, solidBox, Directions.Reverse(dir)))
{
return;
}
}
// Resolve the collision.
if (!entity.Physics.IsColliding && !entity.Physics.ClipCollisionInfo[clipDirection].IsColliding) {
// Determine the penetration.
float penetrationDistance = GetClipPenetration(entityBox, solidBox, clipDirection);
float maxAllowedPenetration = 0.0f;
if (entity.Physics.Velocity[axis] == 0.0f)
maxAllowedPenetration = GetAllowedEdgeClipAmount(entity, other);
// Snap the entity's position to the edge of the solid object.
Vector2F newPos = entity.Position;
newPos[axis] += entity.Physics.Velocity[axis];
newPos -= Directions.ToVector(clipDirection) * penetrationDistance;
if (penetrationDistance <= maxAllowedPenetration)
newPos += Directions.ToVector(clipDirection) * penetrationDistance;
entity.Position = newPos;
entity.Physics.CollisionInfo[clipDirection].SetCollision(other, clipDirection);
}
// Zero the entity's velocity for this axis.
Vector2F velocity = entity.Physics.Velocity;
velocity[axis] = 0.0f;
entity.Physics.Velocity = velocity;
entity.Physics.MovementCollisions[clipDirection] = true;
if (!entity.Physics.CollisionInfo[clipDirection].IsColliding)
entity.Physics.CollisionInfo[clipDirection].SetCollision(other, clipDirection);
// Perform collision dodging.
bool canDodge = true;
if (entity is Player) // TODO: this won't work for when player is knocked back
canDodge = ((Player) entity).Movement.AllowMovementControl && Controls.Arrows[clipDirection].IsDown();
if (entity.Physics.AutoDodges && canDodge) {
if (roomControl.IsSideScrolling && axis == Axes.X &&
(!(entity is Player) || !((Player) entity).Movement.IsOnSideScrollLadder || ((other is Tile) && ((Tile) other).IsInMotion)) &&
(entity.IsOnGround || entity.Physics.PreviousCollisionInfo[Directions.Down].IsColliding))
{
// Step up onto blocks if it is a small enough distance.
PerformSideScrollCollisionSnap(entity, clipDirection, other, solidBox);
}
else {
// Auto dodging.
PerformCollisionDodge(entity, clipDirection, other, solidBox);
}
}
}
// Create a clip collision info between an entity and solid object with a specified clip direction.
private CollisionInfoNew CreateCollisionInfo(Entity entity, object other, Rectangle2F solidBox, int clipDirection)
{
return new CollisionInfoNew() {
IsColliding = true,
Entity = entity,
CollidedObject = other,
CollisionBox = solidBox,
PenetrationDirection = clipDirection,
PenetrationDistance = GetClipPenetration(entity.Physics.PositionedCollisionBox, solidBox, clipDirection),
MaxAllowedPenetrationDistance = GetAllowedEdgeClipAmount(entity, other)
};
}
public CollisionTestSettings(Type entityType, Rectangle2F myBox, Rectangle2F otherBox, float maxZDistance = 10)
{
this.requiredType = entityType;
this.collisionBox1 = myBox;
this.collisionBox2 = otherBox;
this.collisionBoxType1 = CollisionBoxType.Custom;
this.collisionBoxType2 = CollisionBoxType.Custom;
this.requiredFlags = PhysicsFlags.None;
this.maxZDistance = maxZDistance;
}
// Attempt to snap a collision.
private bool PerformSideScrollCollisionSnap(Entity entity, int direction, object solidObject, Rectangle2F solidBox)
{
Rectangle2F entityBox = entity.Physics.PositionedCollisionBox;
float penetrationDistance = GetClipPenetration(
entity.Physics.PositionedCollisionBox, solidBox, direction);
float distanceToEdge = entityBox.Bottom - solidBox.Top;
//Vector2F goalPosition = entity.Position + Directions.ToVector(direction) +
//(Directions.ToVector(Directions.Up) * distanceToEdge);
Vector2F goalPosition = entity.Position +
Directions.ToVector(direction) -
new Vector2F(0.0f, distanceToEdge);
// Check if the distance to the edge is within dodge range.
// Make sure the entity is not colliding when placed at the solid object's edge.
if (distanceToEdge <= entity.Physics.AutoDodgeDistance &&
!IsCollidingAt(entity, goalPosition, false, direction, penetrationDistance))
{
entity.Position = goalPosition;
entity.Physics.MovementCollisions[Directions.Down] = true;
entity.Physics.CollisionInfo[Directions.Down].SetCollision(solidObject, Directions.Down);
return true;
}
return false;
}
// Translates the rectangle based on the translation and precision settings.
private Rectangle NewRect(Rectangle2F destinationRect)
{
if (useTranslation)
return (UseIntegerPrecision ? (Rectangle)new Rectangle2F(GMath.Round(destinationRect.Point + translation), GMath.Round(destinationRect.Size)) : (Rectangle)(destinationRect + translation));
else
return (Rectangle)destinationRect;
}
public void DrawSprite(Sprite sprite, int variantID, Rectangle2F destination, Color color, float depth = 0.0f)
{
if (sprite.Image == null)
return;
for (Sprite part = sprite; part != null; part = part.NextPart) {
Image image = sprite.Image.GetVariant(variantID);
destination.Point = NewPos(destination.Point) + (Vector2F)part.DrawOffset;
spriteBatch.Draw(image, (Rectangle)destination, (Rectangle)part.SourceRect,
(XnaColor)color, 0.0f, Vector2.Zero, SpriteEffects.None, depth);
}
}
// Draws the specified rectangle.
public void DrawRectangle(Rectangle2F rect, float thickness, Color color, float depth = 0.0f)
{
DrawLine(new Line2F(rect.Point, rect.Point + new Vector2F(rect.Width - 1, 0.0f)), thickness, color, depth);
DrawLine(new Line2F(rect.Point, rect.Point + new Vector2F(0.0f, rect.Height - 1)), thickness, color, depth);
DrawLine(new Line2F(rect.Point + rect.Size - Vector2F.One, rect.Point + new Vector2F(rect.Width - 1, 0.0f)), thickness, color, depth);
DrawLine(new Line2F(rect.Point + rect.Size - Vector2F.One, rect.Point + new Vector2F(0.0f, rect.Height - 1)), thickness, color, depth);
}
// Draws part of the image at the specified position.
public void DrawImage(Texture2D texture, Vector2F position, Rectangle2F sourceRect, Color color, double depth = 0.0)
{
spriteBatch.Draw(texture, NewPos(position), (Rectangle)sourceRect, color, 0.0f, Vector2.Zero, 1.0f, SpriteEffects.None, (float)depth);
}
//-----------------------------------------------------------------------------
// Static methods
//-----------------------------------------------------------------------------
public static bool Intersecting(CollisionModel model,
Vector2F modelPosition,
Rectangle2F box)
{
return(Intersecting(model, modelPosition, box, Vector2F.Zero));
}
// Draws part of the image at the specified region.
public void DrawImage(Texture2D texture, Rectangle2F destinationRect, Rectangle2F sourceRect, Vector2F origin, double rotation, Color? color = null, SpriteEffects flipEffect = SpriteEffects.None, double depth = 0.0)
{
spriteBatch.Draw(texture, NewRect(destinationRect), (Rectangle)sourceRect, color ?? XnaColor.White, (float)GMath.ConvertToRadians(rotation), (Vector2)origin, flipEffect, (float)depth);
}
// Creates a copy of a rectangle translated by an amount.
public static Rectangle2F Translate(Rectangle2F r, Vector2F amount)
{
r.Point += amount;
return(r);
}
public void DrawSprite(Sprite sprite, Rectangle2F destination, Color color, float depth = 0.0f)
{
DrawSprite(sprite, 0, destination, color, depth);
}
// Constructs a copy of the specified rectangle.
public Rectangle2F(Rectangle2F r)
{
this.Point = r.Point;
this.Size = r.Size;
}
// Draws the specified filled rectangle.
public void FillRectangle(Rectangle2F rect, Color color, double depth = 0.0)
{
rect.X = GMath.Round(rect.X);
rect.Y = GMath.Round(rect.Y);
DrawImage(white1x1, rect, Vector2F.Zero, 0.0, color, SpriteEffects.None, depth);
//DrawImage(white1x1, rect.Center + 0.5, new Vector2D(0.5, 0.5), rect.Size, 0, color, SpriteEffects.None, depth);
}
/** <summary> Returns true if the specified rectangle is inside this line. </summary> */
public bool Contains(Rectangle2F rect)
{
return false;
}
// Translates the rectangle based on the translation and precision settings.
private Rectangle NewRect(Vector2F position, Vector2F size)
{
Rectangle2F destinationRect = new Rectangle2F(position, size);
if (useTranslation)
return (UseIntegerPrecision ? (Rectangle)new Rectangle2F(GMath.Round(destinationRect.Point + translation), GMath.Round(destinationRect.Size + translation)) : (Rectangle)(destinationRect + translation));
else
return (Rectangle)destinationRect;
}
// Return an enumerable list of solid tiles colliding with the given collision box.
public IEnumerable<Tile> GetSolidTilesColliding(Rectangle2F collisionBox, TileLayerOrder layerOrder = TileLayerOrder.LowestToHighest)
{
Rectangle2I area = GetTileAreaFromRect(collisionBox);
foreach (Tile tile in GetTilesInArea(area, layerOrder)) {
if (tile.IsSolid && tile.CollisionModel != null &&
CollisionModel.Intersecting(tile.CollisionModel, tile.Position, collisionBox))
yield return tile;
}
}
// Attempt to dodge a collision.
private bool PerformCollisionDodge(Entity entity, int direction, object solidObject, Rectangle2F solidBox)
{
// Only dodge if moving perpendicular to the edge.
int axis = Directions.ToAxis(direction);
if (Math.Abs(entity.Physics.Velocity[1 - axis]) > 0.001f)
return false;
// Can't dodge moving tiles.
if ((solidObject is Tile) && ((Tile) solidObject).IsMoving)
return false;
Rectangle2F entityBox = entity.Physics.PositionedCollisionBox;
float penetrationDistance = GetClipPenetration(
entity.Physics.PositionedCollisionBox, solidBox, direction);
// Check dodging for both edges of the solid object.
for (int side = 0; side < 2; side++) {
int moveDirection = (direction + (side == 0 ? 1 : 3)) % 4;
float distanceToEdge = Math.Abs(entityBox.GetEdge(
Directions.Reverse(moveDirection)) - solidBox.GetEdge(moveDirection));
// Check if the distance to the edge is within dodge range.
if (distanceToEdge <= entity.Physics.AutoDodgeDistance) {
float moveAmount = Math.Min(entity.Physics.AutoDodgeSpeed, distanceToEdge);
Vector2F nextPosition = GMath.Round(entity.Position) +
(Directions.ToVector(moveDirection) * moveAmount);
Vector2F goalPosition = entity.Position + Directions.ToVector(direction) +
(Directions.ToVector(moveDirection) * distanceToEdge);
// Make sure the entity is not colliding when placed at the solid object's edge.
if (!IsCollidingAt(entity, nextPosition, false, direction, penetrationDistance) &&
!IsCollidingAt(entity, goalPosition, false, direction, penetrationDistance))
{
entity.Position += Directions.ToVector(moveDirection) * moveAmount;
entity.Physics.CollisionInfo[direction].IsAutoDodged = true;
//entity.Physics.MovementCollisions[direction] = false; // TODO: Figure out complications for removing this.
return true;
}
}
}
return false;
}
// inflateAmount inflates the output rectangle.
public Rectangle2I GetTileAreaFromRect(Rectangle2F rect, int inflateAmount = 0)
{
Rectangle2I area;
area.Point = (Point2I) GMath.Floor(rect.TopLeft / tileGridCellSize);
area.Size = (Point2I) GMath.Ceiling(rect.BottomRight / tileGridCellSize) - area.Point;
if (inflateAmount != 0)
area.Inflate(inflateAmount, inflateAmount);
return Rectangle2I.Intersect(area, new Rectangle2I(Point2I.Zero, gridDimensions));
}
private void ResolveCircularCollision(Entity entity, object solidObject, Rectangle2F solidBox)
{
Rectangle2F collisionBox = entity.Physics.CollisionBox;
Rectangle2F entityBoxPrev = entity.Physics.CollisionBox;
entityBoxPrev.Point += entity.Position;
// If already colliding with the object, then push away from its center.
if (entityBoxPrev.Intersects(solidBox)) {
Vector2F correction = (entity.Position - solidBox.Center).Normalized;
correction = Vector2F.SnapDirectionByCount(correction, 16);
entity.Position += 1.0f * correction;
return;
}
// Predict collisions for each axis.
for (int axis = 0; axis < 2; axis++) {
Rectangle2F entityBox = entity.Physics.CollisionBox;
entityBox.Point += entity.Position;
if (axis == 0)
entityBox.X += entity.Physics.VelocityX;
else
entityBox.Point += entity.Physics.Velocity;
if (entityBox.Intersects(solidBox)) {
// Snap the position.
Vector2F newPos = entity.Position;
if (entityBox.Center[axis] < solidBox.Center[axis])
newPos[axis] = solidBox.TopLeft[axis] - collisionBox.BottomRight[axis];
else
newPos[axis] = solidBox.BottomRight[axis] - collisionBox.TopLeft[axis];
entity.Position = newPos;
Vector2F newVelocity = entity.Physics.Velocity;
if (Math.Abs(entity.Physics.Velocity[1 - axis]) < 0.1f) {
// Slightly push away from the center of the solid object.
Vector2F distance = entity.Physics.PositionedCollisionBox.Center - solidBox.Center;
//Vector2F correction = (entity.Position - solidBox.Center).Normalized;
//correction = Vector2F.SnapDirectionByCount(correction, 16);
if (GMath.Abs(distance[1 - axis]) > 1.0f) {
//distance = GMath.Sqr(GMath.Abs(distance)) * GMath.Sign(distance);
distance = (distance * distance) * GMath.Sign(distance);
//newVelocity[1 - axis] += distance[1 - axis] * 0.015f;
newPos = entity.Position;
newPos[1 - axis] += distance[1 - axis] * 0.015f;
if (!IsCollidingAt(entity, newPos, false))
entity.Position = newPos;
}
}
newVelocity[axis] = 0.0f;
entity.Physics.Velocity = newVelocity;
}
}
}
// Return an enumerable list of tiles touching the given rectangular bounds.
public IEnumerable<Tile> GetTilesTouching(Rectangle2F bounds, TileLayerOrder layerOrder = TileLayerOrder.LowestToHighest)
{
Rectangle2I area = GetTileAreaFromRect(bounds);
foreach (Tile tile in GetTilesInArea(area, layerOrder)) {
if (tile.Bounds.Intersects(bounds))
yield return tile;
}
}
// Returns true if two rectangles share an edge in the given direction.
public static bool AreEdgesAligned(Rectangle2F box1, Rectangle2F box2, int edgeDirection)
{
return Math.Abs(box1.GetEdge(edgeDirection) - box2.GetEdge(edgeDirection)) < 0.1f;
}
//-----------------------------------------------------------------------------
// Tile Mutators
//-----------------------------------------------------------------------------
// Place a tile in highest empty layer at the given location.
// Returns true if there was an empty space to place the tile.
public bool PlaceTileOnHighestLayer(Tile tile, Point2I location)
{
Rectangle2F tileBounds = new Rectangle2F(
location * GameSettings.TILE_SIZE,
tile.Size * GameSettings.TILE_SIZE);
Rectangle2I area = GetTileAreaFromRect(tileBounds);
// Determine which layers are free.
bool[] freeLayers = new bool[layerCount];
for (int i = 0; i < layerCount; i++) {
freeLayers[i] = true;
for (int x = area.Left; x < area.Right && freeLayers[i]; x++) {
for (int y = area.Top; y < area.Bottom && freeLayers[i]; y++) {
Tile t = tiles[x, y, i];
if (t != null)
freeLayers[i] = false;
}
}
}
// Choose the highest free layer.
int layer = -1;
for (int i = layerCount - 1; i >= 0; i--) {
if (freeLayers[i]) {
layer = i;
break;
}
}
if (layer < 0)
return false;
// Place the tile in that layer.
PlaceTile(tile, location, layer);
return true;
}
// Detect a clip collision between the entity and a solid object.
private void DetectClipCollision(Entity entity, object other, Rectangle2F solidBox)
{
// Check if there actually is a collision.
Rectangle2F entityBox = entity.Physics.PositionedCollisionBox;
if (entityBox.Intersects(solidBox)) {
// Determine clip direction.
int clipDirection = GetCollisionClipDirection(entity, other, solidBox);
// Set or replace the collision info for this clip direction.
if (clipDirection >= 0) {
CollisionInfoNew oldCollisionInfo = entity.Physics.ClipCollisionInfo[clipDirection];
CollisionInfoNew newCollisionInfo = CreateCollisionInfo(entity, other, solidBox, clipDirection);
if (!oldCollisionInfo.IsColliding || (newCollisionInfo.PenetrationDistance > oldCollisionInfo.PenetrationDistance))
entity.Physics.ClipCollisionInfo[clipDirection] = newCollisionInfo;
}
}
}
private void UpdateTileGridArea(Tile tile)
{
Rectangle2F tileBounds = new Rectangle2F(tile.Position, tile.Size * GameSettings.TILE_SIZE);
Rectangle2I nextArea = GetTileAreaFromRect(tileBounds);
Rectangle2I prevArea = tile.TileGridArea;
if (nextArea != prevArea) {
// Determine the highest free layer for the tile to move to.
int newLayer = -1;
for (int i = tile.Layer; i < layerCount; i++) {
bool isLayerFree = true;
for (int x = nextArea.Left; x < nextArea.Right && isLayerFree; x++) {
for (int y = nextArea.Top; y < nextArea.Bottom && isLayerFree; y++) {
Tile t = tiles[x, y, i];
if (t != null && t != tile)
isLayerFree = false;
}
}
if (isLayerFree) {
newLayer = i;
break;
}
}
if (newLayer < 0) {
RemoveTile(tile);
return;
}
// Remove the tile from its old area.
for (int x = prevArea.Left; x < prevArea.Right; x++) {
for (int y = prevArea.Top; y < prevArea.Bottom; y++) {
tiles[x, y, tile.Layer] = null;
}
}
// Place the tile into its new area.
for (int x = nextArea.Left; x < nextArea.Right; x++) {
for (int y = nextArea.Top; y < nextArea.Bottom; y++) {
tiles[x, y, tile.Layer] = tile;
}
}
tile.TileGridArea = nextArea;
}
// Check for covered/uncovered tiles.
Rectangle2F tileBoundsOld = tile.PreviousBounds;
Rectangle2F tileBoundsNew = tile.Bounds;
if (tileBoundsOld != tileBoundsNew) {
foreach (Tile t in GetTilesInArea(nextArea).Union(GetTilesInArea(prevArea))) {
Rectangle2F tBounds = t.Bounds;
if (t != tile) {
if (tileBoundsNew.Contains(tBounds) && !tileBoundsOld.Contains(tBounds))
t.OnCoverComplete(tile);
else if (tileBoundsNew.Intersects(tBounds) && !tileBoundsOld.Intersects(tBounds))
t.OnCoverBegin(tile);
else if (tileBoundsOld.Contains(tBounds) && !tileBoundsNew.Contains(tBounds))
t.OnUncoverBegin(tile);
else if (tileBoundsOld.Intersects(tBounds) && !tileBoundsNew.Intersects(tBounds))
t.OnUncoverComplete(tile);
}
}
}
}
// Returns an enumerable list of all possible collisions.
private IEnumerable<CollisionCheck> GetCollisions(Entity entity, Rectangle2F area)
{
// Find nearby solid entities.
if (entity.Physics.CollideWithEntities) {
foreach (Entity other in RoomControl.Entities) {
if (other != entity && CanCollideWithEntity(entity, other)) {
yield return new CollisionCheck() {
SolidBox = other.Physics.PositionedCollisionBox,
SolidObject = other
};
}
}
}
// Find nearby solid tiles tiles.
if (entity.Physics.CollideWithWorld) {
foreach (Tile tile in RoomControl.TileManager.GetTilesTouching(area)) {
if (CanCollideWithTile(entity, tile) && tile.CollisionStyle == CollisionStyle.Rectangular) {
foreach (Rectangle2I box in tile.CollisionModel.Boxes) {
Rectangle2F tileBox = box;
tileBox.Point += tile.Position;
yield return new CollisionCheck() {
SolidBox = tileBox,
SolidObject = tile
};
}
}
}
}
}
// Draws part of the image at the specified position.
public void DrawImage(Texture2D texture, Vector2F position, Rectangle2F sourceRect)
{
spriteBatch.Draw(texture, NewPos(position), (Rectangle)sourceRect, XnaColor.White);
}
// Returns true if the entity allowably clipping the given collision.
private bool IsSafeClipping(Entity entity, int axis, Rectangle2F entityBox, object other, Rectangle2F solidBox)
{
if (entity.Physics.AllowEdgeClipping) {
float allowedEdgeClipAmount = GetAllowedEdgeClipAmount(entity, other);
float penetration = Math.Min(
solidBox.BottomRight[axis] - entityBox.TopLeft[axis],
entityBox.BottomRight[axis] - solidBox.TopLeft[axis]);
return (penetration <= allowedEdgeClipAmount);
}
return false;
}
/** <summary> Returns true if the specified rectangle is inside this line. </summary> */
public bool Contains(Rectangle2F rect)
{
return(false);
}