Develop Reference

Check collision and prevent overlap

I can't seem to figure out how to make this simple animation work, where i have user control over a red square, and it shouldn't overlap/intersect with a black square (e.g. a wall sprite)
My best effort is to have stack data structure of keys pressed and if there is an intersection, then we look at (peek) last key pressed and assign a speed of -1. (See line 67 of code) But this doesn't prevent an overlap. Is there a way that I can make it so the user's red rectangle can't overlap with black?
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Collections;
namespace Movement
{
public partial class Form1 : Form
{
bool moveRight, moveLeft, moveUp, moveDown;
Keys currentInput;
Keys lastInput;
Stack pressedKeys = new Stack();
int speed = 5;
bool collision = false;
public Form1()
{
InitializeComponent();
this.CenterToScreen();
}
private void pbRed_Click(object sender, EventArgs e)
{
}
private void moveTimeEvent(object sender, EventArgs e)
{
currentInput = Keys.KeyCode;
//moving left
if (moveLeft == true && pbRed.Left > 7 )
{
pbRed.Left -= speed;
}
//moving right
if (moveRight == true && pbRed.Left < 750)
{
pbRed.Left += speed;
}
//moving up
if(moveUp == true && pbRed.Top > 7)
{
pbRed.Top -= speed;
}
//moving down
if(moveDown == true && pbRed.Top < 400)
{
pbRed.Top += speed;
}
if (moveLeft == true || moveRight == true || moveUp == true || moveDown == true)
{
pressedKeys.Push(currentInput);
}
Collision();
}
private void Collision()
{
//collision detection
if(pbRed.Bounds.IntersectsWith(pbBlack.Bounds))
{
collision = true;
if(collision)
{
lastInput = (Keys)pressedKeys.Peek();
if(currentInput == lastInput)
{
speed = -1;
}
}
}
}
private void keyisdown(object sender, KeyEventArgs e)
{
if(e.KeyCode == Keys.Left)
{
moveLeft = true;
}
if (e.KeyCode == Keys.Right)
{
moveRight = true;
}
if (e.KeyCode == Keys.Up)
{
moveUp = true;
}
if (e.KeyCode == Keys.Down)
{
moveDown = true;
}
}
private void keyisup(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Left)
{
moveLeft = false;
}
if (e.KeyCode == Keys.Right)
{
moveRight = false;
}
if (e.KeyCode == Keys.Up)
{
moveUp = false;
}
if (e.KeyCode == Keys.Down)
{
moveDown = false;
}
}
}
}

When your speed is 5, don't apply a movement of 5 pixels in one go, but apply the 5 steps separately. Before each step, so before actually moving the rectangle, decide whether that one step movement is allowed.
Also look at vertical and horizontal movement separately.
using System;
using System.Drawing;
using System.Windows.Forms;
namespace Movement
{
public partial class Form1 : Form
{
bool moveRight, moveLeft, moveUp, moveDown;
int speed = 5;
public Form1()
{
InitializeComponent();
this.CenterToScreen();
}
private void moveTimeEvent(object sender, EventArgs e)
{
// Get movement vector
Point movement = new Point(0, 0);
if (moveLeft) movement.X -= 1;
if (moveRight) movement.X += 1;
if (moveUp) movement.Y -= 1;
if (moveDown) movement.Y += 1;
// Speed defines how many steps we move
for (int i=1; i<= speed; i++)
{
// Check vertical movement allowed
if (movement.X != 0)
{
Rectangle newPosition = pbRed.Bounds;
newPosition.X += movement.X;
if (!CheckCollision(newPosition))
{
movement.X = 0;
}
}
// Check horizontal movement allowed
if (movement.Y != 0)
{
Rectangle newPosition = pbRed.Bounds;
newPosition.X += movement.X;
newPosition.Y += movement.Y;
if (!CheckCollision(newPosition))
{
movement.Y = 0;
}
}
// Apply Actual movement
if (!movement.IsEmpty)
{
Rectangle newPosition = pbRed.Bounds;
newPosition.X += movement.X;
newPosition.Y += movement.Y;
pbRed.Bounds = newPosition;
}
}
}
// Returns true when movingRecht is allowed position
private bool CheckCollision(Rectangle movingRect)
{
bool lResult = true;
//collision detection
lResult = lResult && !pbBlack.Bounds.IntersectsWith(movingRect);
// Check we remain inside the form
lResult = lResult && movingRect.Left >= 0;
lResult = lResult && movingRect.Top >= 0;
lResult = lResult && movingRect.Right <= ClientRectangle.Right;
lResult = lResult && movingRect.Bottom <= ClientRectangle.Bottom;
return lResult;
}
private void keyisdown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Left)
{
moveLeft = true;
}
if (e.KeyCode == Keys.Right)
{
moveRight = true;
}
if (e.KeyCode == Keys.Up)
{
moveUp = true;
}
if (e.KeyCode == Keys.Down)
{
moveDown = true;
}
}
private void keyisup(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Left)
{
moveLeft = false;
}
if (e.KeyCode == Keys.Right)
{
moveRight = false;
}
if (e.KeyCode == Keys.Up)
{
moveUp = false;
}
if (e.KeyCode == Keys.Down)
{
moveDown = false;
}
}
}
}

Selected PictureBox don't move on KeyDown

I have PictureBoxes and I just choose from them via the onClick function and then if it doesn't have a "King" tag, I can move with it ... But I can only do that if I have the MessageBox there (It was only there for the test , if it takes a tag) and if I remove it now, I can't move with it.
private void PictureBoxIsClicked(object sender, MouseEventArgs e)
{
selectedPlayer = (PictureBox)sender;
if (e.Button == MouseButtons.Left)
{
//Choosing King
if (isClicked == true && readyToPlay == false)
{
selectedPlayer.Image = Properties.Resources.CharRed;
selectedPlayer.Tag = "King";
isKing = true;
}
isClicked = false;
//Select pictureBox to move
if (readyToPlay == true)
{
label2.Text = String.Format("{0}", selectedPlayer.Tag.ToString());
label1.Show();
MessageBox.Show(selectedPlayer.Tag.ToString());
}
}
}
private void KeyIsDown(object sender, KeyEventArgs e)
{
if(selectedPlayer.Tag.ToString() != "King")
{
//Move forward
if (e.KeyCode == Keys.Up)
{
forward = true;
}
//Move backward
if (e.KeyCode == Keys.Down)
{
backward = true;
}
//Move Left
if (e.KeyCode == Keys.Left)
{
left = true;
}
//Move right
if (e.KeyCode == Keys.Right)
{
right = true;
}
}
}
private void GameTimerEvent(object sender, EventArgs e)
{
//Movement - Player
if(forward == true)
{
selectedPlayer.Top -= 120;
forward = false;
}
if (backward == true)
{
selectedPlayer.Top += 120;
backward = false;
}
if (left == true)
{
selectedPlayer.Left -= 120;
left = false;
}
if (right == true)
{
selectedPlayer.Left += 120;
right = false;
}
}
Why does it fail?

How do I move an object using a timer and the key press event (Like snake)

I want to move a button automatically using a timer and want it to change direction when another key is pressed, kinda like what happens in snake
I have used a string to set what the direction should be, but this doesn't work.
string x = "right";
public Form1()
{
InitializeComponent();
timer1.Interval = 1000;
timer1.Start();
}
private void Player_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.W)
{
string x = "up";
}
else if (e.KeyCode == Keys.S)
{
string x = "down";
}
else if (e.KeyCode == Keys.D)
{
string x = "right";
}
else if (e.KeyCode == Keys.A)
{
string x = "left";
}
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void Timer1_Tick(object sender, EventArgs e)
{
while (x == "up")
{
Player.Top -= 10;
}
while (x == "down")
{
Player.Top += 10;
}
while (x == "right")
{
Player.Left += 10;
}
while (x == "left")
{
Player.Left -= 10;
}
}
}
The button just disappears, but I want it to move by ten until it gets a key press like "D" then it changes direction

1: You are creating variable 'x' every time means locally in player_keyDown event so create it globally.
2: you are using while loop it, not needed as you are already using timer_tick.
3: Instead of Top, Left use Location property of button it gives you X, Y co-ordinate
public partial class Form2 : Form
{
public Form2()
{
InitializeComponent();
timer1.Interval = 1000;
timer1.Start();
}
string x = "right";
private void Player_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.W)
{
x = "up";
}
else if (e.KeyCode == Keys.S)
{
x = "down";
}
else if (e.KeyCode == Keys.D)
{
x = "right";
}
else if (e.KeyCode == Keys.A)
{
x = "left";
}
}
private void timer1_Tick(object sender, EventArgs e)
{
if (x == "up")
{
Player.Location = new System.Drawing.Point(Player.Location.X, Player.Location.Y - 10);
}
if (x == "down")
{
Player.Location = new System.Drawing.Point(Player.Location.X, Player.Location.Y + 10);
}
if (x == "right")
{
Player.Location = new System.Drawing.Point(Player.Location.X + 10, Player.Location.Y);
}
if (x == "left")
{
Player.Location = new System.Drawing.Point(Player.Location.X - 10, Player.Location.Y);
}
}
}

moving a image without selecting the buttons - C#

I want to create a game (Multicolor maze), involves using a image ove using arrow keys, but during runtime, the buttons are selected and not the image when arrow keys are pressed?
Runtime
[UPDATED]
public Form1()
{
InitializeComponent();
this.KeyDown += new System.Windows.Forms.KeyEventHandler(this.Form1_KeyDown);
System.Console.WriteLine("here");
}
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
// for the image move
int x = Convert.ToInt32(HeartSprite.Location.X);
int y = Convert.ToInt32(HeartSprite.Location.Y);
if (e.KeyCode == Keys.Right) x = x += 25;
else if (e.KeyCode == Keys.Left) x -= 25;
else if (e.KeyCode == Keys.Up) y -= 25;
else if (e.KeyCode == Keys.Down) y += 25;
HeartSprite.Location = new Point(x, y);
e.Handled = true;
}

Try setting e.Handled = true; at the end of the function to block the buttons stealing the input
Your code becomes:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
this.KeyDown += new System.Windows.Forms.KeyEventHandler(this.Form1_KeyDown);
}
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
// for the image move
int x = Convert.ToInt32(HeartSprite.Location.X);
int y = Convert.ToInt32(HeartSprite.Location.Y);
if (e.KeyCode == Keys.Right) x += 25;
else if (e.KeyCode == Keys.Left) x -= 25;
else if (e.KeyCode == Keys.Up) y -= 25;
else if (e.KeyCode == Keys.Down) y += 25;
HeartSprite.Location = new Point(x, y);
e.Handled = true;
}
}

How to prevent two events about the same thing happening

Basically,I am a beginner in C# and I just started working on a simple platformer game following a basic Visual Studio 2015 tutorial.This is the code:
public partial class Form1 : Form
{
bool goleft = false;
bool goright = false;
bool jumping = false;
int JumpSpeed = 10;
int force = 8;
int score = 0;
public Form1()
{
InitializeComponent();
}
private void keyisdown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Left)
{
goleft = true;
}
if (e.KeyCode == Keys.Right)
{
goright = true;
}
if (e.KeyCode == Keys.Space && !jumping)
{
jumping = true;
}
}
private void keyisup(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Left)
{
goleft = false;
}
if (e.KeyCode == Keys.Right)
{
goright = false;
}
if (jumping)
{
jumping = false;
}
}
private void timer1_Tick(object sender, EventArgs e)
{
player.Top += JumpSpeed;
if (jumping && force < 0)
{
jumping = false;
}
if (goleft)
{
player.Left -= 5;
}
if (goright)
{
player.Left += 5;
}
if (jumping)
{
JumpSpeed = -12;
force -= 1;
}
else
{
JumpSpeed = 12;
}
foreach (Control x in this.Controls)
{
if (x is PictureBox && x.Tag == "p")
{
if (player.Bounds.IntersectsWith(x.Bounds) && !jumping)
{
force = 8;
player.Top = x.Top - player.Height;
}
}
if (player.Bounds.IntersectsWith(Door.Bounds))
{
timer1.Stop();
MessageBox.Show("You Won!");
this.Close();
}
}
}
}
The gravity force and everything works great EXCEPT for one big problem with the player that I definitely can't solve without some help.
The problem is: the player is completely glitched and it keeps going up and down. I realised that this is because of two lines in private void timer1_Tick(object sender, EventArgs e):
player.Top += JumpSpeed;
and
player.Top = x.Top - player.Height;
Both of these try to change player.Top and interfere with each other. The trouble is that I can't just cut one of the two without destroying the gravity force code. What I think might work is applying player.Top += JumpSpeed; ONLY if(player.Bounds.IntersectsWith(x.Bounds) && !jumping) = false but I don't know how to write the code this way at all (previous tries always ended up with errors).
Thanks in advance for any help and please forgive any grammar errors that I made because I am not a native english speaker.

I don't know how your Form looks like, but with what you provided I would change the code like that:
public partial class Form1 : Form
{
bool goleft = false;
bool goright = false;
int JumpSpeed = 0; //current vertical speed
int force = 8; //initial jump speed
int score = 0;
public Form1()
{
InitializeComponent();
}
private void keyisdown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Left)
{
goleft = true;
}
if (e.KeyCode == Keys.Right)
{
goright = true;
}
if (e.KeyCode == Keys.Space && JumpSpeed==0) //JumpSpeed==0 to prevent "double jump"
{
JumpSpeed = force; //start jumping with full power
}
}
private void keyisup(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Left)
{
goleft = false;
}
if (e.KeyCode == Keys.Right)
{
goright = false;
}
}
private void timer1_Tick(object sender, EventArgs e)
{
if (goleft)
{
player.Left -= 5;
}
if (goright)
{
player.Left += 5;
}
JumpSpeed -= 1; //decrement the vertical speed = gravity -> choose higher value to bring him back on the ground quicker
player.Top -= JumpSpeed;
if (player.Bounds.IntersectsWith(Door.Bounds))
{
timer1.Stop();
MessageBox.Show("You Won!");
this.Close();
}
foreach (PictureBox x in this.Controls.OfType<PictureBox>())
{
if (x.Tag == "p")
{
if (player.Bounds.IntersectsWith(x.Bounds)) //if the player should be able to jump/walk on something the code is
{
player.Top = x.Top - player.Height;
JumpSpeed = 0; //the player stops falling
}
}
}
}
}
To make sure to player does not fall out of the window place PictureBoxes with tag == p on the floor!
PS:
Feel free to leave a comment!