sneak/Shared/Player.cs

236 lines
7.9 KiB
C#

using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using System;
using System.Collections.Generic;
namespace SemiColinGames {
public class Player {
private enum Pose { Walking, Standing, SwordSwing, Jumping };
private const int moveSpeed = 180;
private const int jumpSpeed = -600;
private const int gravity = 1600;
// Details of the sprite image.
// player_1x is 48 x 48, yOffset=5, halfSize=(7, 14)
// Ninja_Female is 96 x 64, yOffset=1, halfSize=(11, 24)
private const int spriteWidth = 96;
private const int spriteHeight = 64;
private const int spriteCenterYOffset = 1;
// Details of the actual Player model.
// Position is tracked at the Player's center. The Player's bounding box is a rectangle
// centered at that point and extending out by halfSize.X and halfSize.Y.
private Vector2 position;
private Vector2 halfSize = new Vector2(11, 24);
// Fractional-pixel movement that was left over from a previous frame's movement.
// Useful so that we can run at a slow time-step and still get non-zero motion.
private Vector2 residual = Vector2.Zero;
private int jumps = 0;
private Pose pose = Pose.Jumping;
private double swordSwingTime = 0;
private int swordSwingNum = 0;
private float ySpeed = 0;
private float invincibilityTime = 0;
public Player(Vector2 position, int facing) {
this.position = position;
Facing = facing;
Health = MaxHealth;
}
public int MaxHealth { get; private set; } = 3;
public int Health { get; private set; }
public int Facing { get; private set; }
public Vector2 Position { get { return position; } }
public void Update(float modelTime, World world, History<Input> input) {
AABB BoxOffset(Vector2 position, int yOffset) {
return new AABB(new Vector2(position.X, position.Y + yOffset), halfSize);
}
AABB Box(Vector2 position) {
return BoxOffset(position, 0);
}
invincibilityTime -= modelTime;
Vector2 inputMovement = HandleInput(modelTime, input);
Vector2 movement = Vector2.Add(residual, inputMovement);
residual = new Vector2(movement.X - (int) movement.X, movement.Y - (int) movement.Y);
// Broad test: remove all collision targets nowhere near the player.
// TODO: don't allocate a list here.
var candidates = new List<AABB>();
// Expand the box in the direction of movement. The center is the midpoint of the line
// between the player's current position and their desired movement. The width increases by
// the magnitude of the movement in each direction. We add 1 to each dimension just to be
// sure (the only downside is a small number of false-positive AABBs, which should be
// discarded by later tests anyhow.)
AABB largeBox = new AABB(
Vector2.Add(position, Vector2.Divide(movement, 2)),
Vector2.Add(halfSize, new Vector2(Math.Abs(movement.X) + 1, Math.Abs(movement.Y) + 1)));
foreach (var box in world.CollisionTargets) {
if (box.Intersect(largeBox) != null) {
// Debug.AddRect(box, Color.Green);
candidates.Add(box);
}
}
bool harmedByCollision = false;
// TODO: pass in movePoints to Line.Rasterize instead of having that function allocate a
// new array.
Point[] movePoints = Line.Rasterize(0, 0, (int) movement.X, (int) movement.Y);
for (int i = 1; i < movePoints.Length; i++) {
int dx = movePoints[i].X - movePoints[i - 1].X;
int dy = movePoints[i].Y - movePoints[i - 1].Y;
if (dy != 0) {
Vector2 newPosition = new Vector2(position.X, position.Y + dy);
AABB player = Box(newPosition);
bool reject = false;
foreach (var box in candidates) {
if (box.Intersect(player) != null) {
Debug.AddRect(box, Color.Cyan);
reject = true;
if (box.Tile?.IsHazard ?? false) {
Debug.AddRect(box, Color.Red);
harmedByCollision = true;
}
}
}
if (!reject) {
position = newPosition;
}
}
if (dx != 0) {
Vector2 newPosition = new Vector2(position.X + dx, position.Y);
AABB player = Box(newPosition);
bool reject = false;
foreach (var box in candidates) {
if (box.Intersect(player) != null) {
Debug.AddRect(box, Color.Cyan);
reject = true;
if (box.Tile?.IsHazard ?? false) {
Debug.AddRect(box, Color.Red);
harmedByCollision = true;
}
}
}
if (!reject) {
position = newPosition;
}
}
}
bool standingOnGround = false;
AABB groundIntersect = BoxOffset(position, 1);
foreach (var box in candidates) {
if (groundIntersect.Intersect(box) != null) {
Debug.AddRect(box, Color.Cyan);
standingOnGround = true;
if (box.Tile?.IsHazard ?? false) {
Debug.AddRect(box, Color.Red);
harmedByCollision = true;
}
}
}
if (standingOnGround) {
jumps = 1;
ySpeed = -0.0001f;
Debug.AddRect(Box(position), Color.Cyan);
} else {
jumps = 0;
Debug.AddRect(Box(position), Color.Orange);
}
if (harmedByCollision && invincibilityTime <= 0) {
world.ScreenShake();
Health -= 1;
invincibilityTime = 0.6f;
}
if (inputMovement.X > 0) {
Facing = 1;
} else if (inputMovement.X < 0) {
Facing = -1;
}
if (swordSwingTime > 0) {
pose = Pose.SwordSwing;
} else if (jumps == 0) {
pose = Pose.Jumping;
} else if (inputMovement.X != 0) {
pose = Pose.Walking;
} else {
pose = Pose.Standing;
}
}
// Returns the desired (dx, dy) for the player to move this frame.
Vector2 HandleInput(float modelTime, History<Input> input) {
Vector2 result = new Vector2() {
X = input[0].Motion.X * moveSpeed * modelTime
};
if (input[0].Jump && !input[1].Jump && jumps > 0) {
jumps--;
ySpeed = jumpSpeed;
}
if (input[0].Attack && !input[1].Attack && swordSwingTime <= 0) {
swordSwingTime = 0.3;
swordSwingNum++;
SoundEffects.SwordSwings[swordSwingNum % SoundEffects.SwordSwings.Length].Play();
}
result.Y = ySpeed * modelTime;
ySpeed += gravity * modelTime;
swordSwingTime -= modelTime;
if (input[0].IsAbsoluteMotion) {
if (input[1].Motion.X == 0) {
result.X = input[0].Motion.X;
} else {
result.X = 0;
}
}
return result;
}
private Rectangle GetTextureSource(Pose pose) {
double time = Clock.ModelTime.TotalSeconds;
switch (pose) {
case Pose.Walking:
case Pose.Jumping:
return Sprites.Ninja.GetTextureSource("run", time);
case Pose.SwordSwing:
// TODO: make a proper animation class & FSM-driven animations.
return Sprites.Ninja.GetTextureSource(
"attack_sword", 0.3 - swordSwingTime);
case Pose.Standing:
default:
return Sprites.Ninja.GetTextureSource("idle", time);
}
}
public void Draw(SpriteBatch spriteBatch) {
Rectangle textureSource = GetTextureSource(pose);
Vector2 spriteCenter = new Vector2(spriteWidth / 2, spriteHeight / 2 + spriteCenterYOffset);
SpriteEffects effect = Facing == 1 ?
SpriteEffects.None : SpriteEffects.FlipHorizontally;
Color color = Color.White;
if (invincibilityTime > 0 && invincibilityTime % 0.2f > 0.1f) {
color = new Color(0.5f, 0.5f, 0.5f, 0.5f);
}
spriteBatch.Draw(Textures.Ninja.Get, Vector2.Floor(position), textureSource, color, 0f,
spriteCenter, Vector2.One, effect, 0f);
}
}
}