XNA 4.0 Finding the problem with the placement algorithm
I am working on a personal project and I still really love XNA and C # (I have experience with Visual Basic and C ++). This project is just testing the code and algorithms before I start my real game.
The problem I am facing is that I am trying to create a sphere on the map when I press enter, however I do not want the sphere to appear on top of each other or the player because I have a very basic collision detection system.
The problem is the search room returns some weird rectangles even when it should just find a spot at the start. Also sometimes it just spawns a sphere on top of the other. Which will crash if I transfer the player to the orbs.
Here's where the problem should lie -
if (currentKeyState.IsKeyDown(Keys.Enter) && newBallDelay == 0)
{
Npcs newBall = new Npcs();
//find room
Rectangle rect;
if (findRoom(newBall, ref rect))
{
newBall.postion = new Vector2(rect.X, rect.Y);
characters.Add(newBall); //adds to a list of Npcs which is drawn in a foreach loop
newBallDelay = 1; //prevents from adding too many spheres at once
}
}
which calls
bool findRoom(Npcs newObject, ref Rectangle rectObject)
{
Rectangle player = new Rectangle((int)spritelocation.X, (int)spritelocation.Y, (int)sprite.Bounds.Width/4, (int)sprite.Bounds.Height/4);
Rectangle check;
for (int i = 0; i < characters.Count; i++)
{
check = new Rectangle((int)characters[i].postion.X, (int)characters[i].postion.Y, (int)characters[i].size.X, (int)characters[i].size.Y);
for (int j = 0; j < 50; j++)
{
rectObject = new Rectangle(i * (int)newObject.size.X * 2, j * (int)newObject.size.Y * 2, (int)newObject.size.X, (int)newObject.size.Y); //size.X and size.Y are the height and width of the object, this creates rectangular grid to check through.
if (!rectObject.Intersects(player) && !rectObject.Intersects(check))
return (true);
}
}
return (false);
}
I doubt this is relevant, but for newballdelay I have this in an update
if (newBallDelay > 0)
{
newBallDelay++;
if (newBallDelay == 50)
newBallDelay = 0;
}
Thanks for taking the time to watch. Again I am new to the site and I think I should consider myself new when coding, so any advice or guidance would be appreciated.
Edit: Fixed internal for loop. Checked and incremented i, not j. However, the problem is.
Edit 2: The FindRoom algorithm seems to return one of two positions regardless of whether there is something in that location or not.
Edit 3: Minor issue found. The height and width of the sprite rectangle must be divided by 4 for correct sprite detection.
Here's my entire code if it helps (sorry if it's messy and doesn't follow proper conventions, I'm still involved)
public class Game1 : Microsoft.Xna.Framework.Game
{
GraphicsDeviceManager graphics;
SpriteBatch spriteBatch;
Texture2D sprite;
Texture2D background;
Texture2D sphere;
bool walking = false;
int walkSpeed = 2;
int newBallDelay = 0;
//bool jump = false;
int runSpeed = 5;
int frame = 0;
Random rand = new Random();
int walkdir = 3; //0 = down, 1 = left, 2 = right, 3 = up
Vector2 spritelocation = new Vector2(0,0);
int imageH = 0;
int imageW = 0;
float elapsed = 0;
private const int Frames = 4;
private float frameSpeed = 0.15f;
List<Npcs> characters = new List<Npcs>();
Npcs ball = new Npcs();
Npcs ball2 = new Npcs();
Camera2d cam = new Camera2d();
private SpriteBatch batch;
SpriteFont Font1;
Vector2 FontPos;
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = "Content";
}
protected override void Initialize()
{
// TODO: Add your initialization logic here
IsMouseVisible = true;
Window.AllowUserResizing = true;
base.Initialize();
}
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
ball.size = (new Vector2(50, 50));
ball.postion = (new Vector2(50, 50));
characters.Add(ball);
ball2.size = (new Vector2(50, 50));
ball2.postion = (new Vector2(160, 80));
characters.Add(ball2);
spriteBatch = new SpriteBatch(GraphicsDevice);
sprite = Content.Load<Texture2D>("sprite\\scaled");
background = Content.Load<Texture2D>("sprite\\grass");
sphere = Content.Load<Texture2D>("sprite\\ball");
imageW = sprite.Bounds.Width;
imageH = sprite.Bounds.Height;
cam.Pos = new Vector2(350, 50);
//cam.Rotation = 0.5f;
// cam.Zoom = 2.0f // Example of Zoom in
// cam.Zoom = 0.5f // Example of Zoom out
spriteBatch = new SpriteBatch(GraphicsDevice);
Font1 = Content.Load<SpriteFont>("LucidaConsole");
batch = new SpriteBatch(this.graphics.GraphicsDevice);
FontPos = new Vector2(graphics.GraphicsDevice.Viewport.Width - 90, 20);
}
protected override void UnloadContent()
{
// TODO: Unload any non ContentManager content here
}
protected override void Update(GameTime gameTime)
{
// Allows the game to exit
if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)
this.Exit();
getInput();
// TODO: Add your update logic here
elapsed += (float)gameTime.ElapsedGameTime.TotalSeconds;
//Delay for ball
if (newBallDelay > 0)
{
newBallDelay++;
if (newBallDelay == 50)
newBallDelay = 0;
}
checkCollsion();
base.Update(gameTime);
}
protected override void Draw(GameTime gameTime)
{
graphics.PreferredBackBufferWidth = 1366;
graphics.PreferredBackBufferHeight = 728;
graphics.GraphicsDevice.Clear(Color.CornflowerBlue);
// TODO: Add your drawing code here
//// if using XNA 4.0
spriteBatch.Begin(SpriteSortMode.BackToFront,BlendState.AlphaBlend,null,null,null,null, cam.get_transformation(null));
//spriteBatch.Draw(background, new Vector2(-2000,-2000), new Rectangle(0,0,4000,4000), Color.White);
for (int i = 0; i < characters.Count(); i++ )
{
spriteBatch.Draw(sphere, characters[i].postion, new Rectangle(0, 0, (int)Math.Round(characters[i].size.X), (int)Math.Round(characters[i].size.Y)), Color.White);
}
elapsed += (int)gameTime.ElapsedGameTime.TotalSeconds;
while (elapsed > frameSpeed && walking)
{
frame++;
elapsed = 0;
frame = frame % Frames;
}
if (!walking)
spriteBatch.Draw(sprite, spritelocation, new Rectangle(0, walkdir * (imageH / 4), (imageW / 4), (imageH / 4)), Color.White);
else
spriteBatch.Draw(sprite, spritelocation, new Rectangle(frame * (imageW / 4), walkdir * (imageH / 4), (imageW / 4), (imageH / 4)), Color.White);
spriteBatch.End();
base.Draw(gameTime);
}
protected void getInput() //Recieves keyboard input
{
KeyboardState currentKeyState = Keyboard.GetState();
if (currentKeyState.IsKeyDown(Keys.Up))
{
walkdir = 3;
walking = true;
if ((currentKeyState.IsKeyDown(Keys.LeftShift)))
{
frameSpeed = 0.05f;
spritelocation.Y -= runSpeed;
cam.Move(new Vector2(0, -runSpeed));
}
else
{
frameSpeed = 0.15f;
spritelocation.Y -= walkSpeed;
cam.Move(new Vector2(0, -walkSpeed));
}
}
else if (currentKeyState.IsKeyDown(Keys.Down))
{
walkdir = 0;
walking = true;
if ((currentKeyState.IsKeyDown(Keys.LeftShift)))
{
frameSpeed = 0.05f;
spritelocation.Y += runSpeed;
cam.Move(new Vector2(0, runSpeed));
}
else
{
frameSpeed = 0.15f;
spritelocation.Y += walkSpeed;
cam.Move(new Vector2(0, walkSpeed));
}
}
else if (currentKeyState.IsKeyDown(Keys.Right))
{
walkdir = 2;
walking = true;
if ((currentKeyState.IsKeyDown(Keys.LeftShift)))
{
frameSpeed = 0.05f;
spritelocation.X += runSpeed;
cam.Move(new Vector2(runSpeed, 0));
}
else
{
frameSpeed = 0.15f;
spritelocation.X += walkSpeed;
cam.Move(new Vector2(walkSpeed, 0));
}
}
else if (currentKeyState.IsKeyDown(Keys.Left))
{
walkdir = 1;
walking = true;
if ((currentKeyState.IsKeyDown(Keys.LeftShift)))
{
frameSpeed = 0.05f;
spritelocation.X -= runSpeed;
cam.Move(new Vector2(-runSpeed, 0));
}
else
{
frameSpeed = 0.15f;
spritelocation.X -= walkSpeed;
cam.Move(new Vector2(-walkSpeed, 0));
}
}
else
{
walking = false;
frameSpeed = 1f;
}
if (currentKeyState.IsKeyDown(Keys.Enter) && newBallDelay == 0)
{
Npcs newBall = new Npcs();
//find room
Rectangle rect = new Rectangle(0,0,(int)newBall.size.X,(int)newBall.size.Y);
if (findRoom(newBall, ref rect))
{
newBall.postion = new Vector2(rect.X, rect.Y);
characters.Add(newBall);
newBallDelay = 1;
}
} //if enter key is hit
} //get input
bool findRoom(Npcs newObject, ref Rectangle rectObject)
{
Rectangle player = new Rectangle((int)spritelocation.X, (int)spritelocation.Y, (int)sprite.Bounds.Width/4, (int)sprite.Bounds.Height/4);
Rectangle check;
for (int i = 0; i < characters.Count; i++)
{
check = new Rectangle((int)characters[i].postion.X, (int)characters[i].postion.Y, (int)characters[i].size.X, (int)characters[i].size.Y);
for (int j = 0; j < 50; j++)
{
rectObject = new Rectangle(i * (int)newObject.size.X * 2, j * (int)newObject.size.Y * 2, (int)newObject.size.X, (int)newObject.size.Y); //size.X and size.Y are the height and width of the object, this creates rectangular grid to check through.
if (!rectObject.Intersects(player) && !rectObject.Intersects(check))
return (true);
}
}
return (false);
}
void checkCollsion(Npcs character, int index)
{
Rectangle char1 = new Rectangle((int)character.postion.X, (int)character.postion.Y, (int)character.size.X, (int)character.size.Y);
Rectangle char2 = new Rectangle();
for (int i = 0; i < characters.Count(); i++)
{
if (i != index)
{
char2 = new Rectangle((int)characters[i].postion.X, (int)characters[i].postion.Y, (int)characters[i].size.X, (int)characters[i].size.Y);
if (char1.Intersects(char2))
{
characters[i].hit(walkdir, (int)character.speed);
checkCollsion(characters[i], i);
}
}
}
character.speed = 0.0f;
}
void checkCollsion()
{
Rectangle char1 = new Rectangle((int)spritelocation.X, (int)spritelocation.Y, (int)sprite.Bounds.Width/4 - 10, (int)sprite.Bounds.Height/4 - 15);
Rectangle char2 = new Rectangle();
for (int i = 0; i < characters.Count(); i++)
{
char2 = new Rectangle((int)characters[i].postion.X, (int)characters[i].postion.Y, (int)characters[i].size.X, (int)characters[i].size.Y);
if (char1.Intersects(char2))
{
characters[i].hit(walkdir, runSpeed);
checkCollsion(characters[i], i);
}
}
}
}
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