Эффект воды - Visual Basic .NET

Формулировка задачи:

Imports System
Imports System.Drawing
Imports System.Collections
Imports System.Windows.Forms
Imports System.Drawing.Imaging
Imports System.Runtime.InteropServices
 
Public Class EfeitoAgua
 
    Inherits System.Windows.Forms.Panel
    Private effectTimer As System.Windows.Forms.Timer
    Private tmrBalance As System.Windows.Forms.Timer
    Private components As System.ComponentModel.IContainer
    Private _bmp As Bitmap
    Private _waves As Short(,,)
    Private _waveWidth As Integer
    Private _waveHeight As Integer
    Private _activeBuffer As Integer = 0
    Private _weHaveWaves As Boolean
    Private _bmpHeight As Integer, _bmpWidth As Integer
    Private _bmpBytes As Byte()
    Private _bmpBitmapData As BitmapData
    Private _scale As Integer
    Private __IsBusy As Boolean
 
    Private Sub InitializeComponent()
        Me.components = New System.ComponentModel.Container()
        Me.effectTimer = New System.Windows.Forms.Timer(Me.components)
        Me.tmrBalance = New System.Windows.Forms.Timer(Me.components)
 
        AddHandler Me.effectTimer.Tick, AddressOf Me.effectTimer_Tick
        AddHandler Me.tmrBalance.Tick, AddressOf Me.tmrBalance_Tick
        AddHandler Me.Paint, AddressOf Me.WaterEffectControl_Paint
        AddHandler Me.MouseMove, AddressOf Me.WaterEffectControl_MouseMove
    End Sub
 
    Public Sub New()
        InitializeComponent()
        effectTimer.Enabled = True
        effectTimer.Interval = 100
        tmrBalance.Interval = 1000
        SetStyle(ControlStyles.UserPaint, True)
        SetStyle(ControlStyles.AllPaintingInWmPaint, True)
        SetStyle(ControlStyles.DoubleBuffer, True)
        Me.BackColor = Color.Transparent
        _weHaveWaves = False
        _scale = 1
    End Sub
 
    Public Sub New(ByVal bmp As Bitmap)
        Me.New()
        Me.ImageBitmap = bmp
    End Sub
 
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If components IsNot Nothing Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub
 
    Private Sub effectTimer_Tick(ByVal sender As Object, ByVal e As System.EventArgs)
        If _weHaveWaves Then
            Invalidate()
            ProcessWaves()
        End If
    End Sub
    Private Sub tmrBalance_Tick(ByVal sender As Object, ByVal e As System.EventArgs)
        __IsBusy = Not __IsBusy
    End Sub
 
    Public Sub WaterEffectControl_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs)
        If IsNothing(_bmp) Then Return
        Dim tmp As Bitmap = Nothing
 
        On Error Resume Next
 
        tmp = DirectCast(_bmp.Clone(), Bitmap)
        Dim xOffset As Integer, yOffset As Integer
        Dim alpha As Byte
 
        If _weHaveWaves Then
            Dim tmpData As BitmapData = tmp.LockBits(New Rectangle(0, 0, _bmpWidth, _bmpHeight), ImageLockMode.ReadWrite, PixelFormat.Format32bppArgb)
            Dim tmpBytes As Byte() = New Byte(_bmpWidth * _bmpHeight * 4 - 1) {}
 
            Marshal.Copy(tmpData.Scan0, tmpBytes, 0, _bmpWidth * _bmpHeight * 4)
 
            For x As Integer = 1 To _bmpWidth - 2
                For y As Integer = 1 To _bmpHeight - 2
                    Dim waveX As Integer = CInt(x) >> _scale
                    Dim waveY As Integer = CInt(y) >> _scale
 
                    If waveX <= 0 Then
                        waveX = 1
                    End If
                    If waveY <= 0 Then
                        waveY = 1
                    End If
                    If waveX >= _waveWidth - 1 Then
                        waveX = _waveWidth - 2
                    End If
                    If waveY >= _waveHeight - 1 Then
                        waveY = _waveHeight - 2
                    End If
 
                    xOffset = (_waves(waveX - 1, waveY, _activeBuffer) - _waves(waveX + 1, waveY, _activeBuffer)) >> 3
                    yOffset = (_waves(waveX, waveY - 1, _activeBuffer) - _waves(waveX, waveY + 1, _activeBuffer)) >> 3
 
                    If (xOffset <> 0) OrElse (yOffset <> 0) Then
                        If x + xOffset >= _bmpWidth - 1 Then
                            xOffset = _bmpWidth - x - 1
                        End If
                        If y + yOffset >= _bmpHeight - 1 Then
                            yOffset = _bmpHeight - y - 1
                        End If
                        If x + xOffset < 0 Then
                            xOffset = -x
                        End If
                        If y + yOffset < 0 Then
                            yOffset = -y
                        End If
                        If xOffset <= 0 Then xOffset = 0
 
                        alpha = CByte(200 - xOffset)
                        If alpha < 0 Then
                            alpha = 0
                        End If
                        If alpha > 255 Then
                            alpha = 254
                        End If
                        tmpBytes(4 * (x + y * _bmpWidth)) = _bmpBytes(4 * (x + xOffset + (y + yOffset) * _bmpWidth))
                        tmpBytes(4 * (x + y * _bmpWidth) + 1) = _bmpBytes(4 * (x + xOffset + (y + yOffset) * _bmpWidth) + 1)
                        tmpBytes(4 * (x + y * _bmpWidth) + 2) = _bmpBytes(4 * (x + xOffset + (y + yOffset) * _bmpWidth) + 2)
                        tmpBytes(4 * (x + y * _bmpWidth) + 3) = alpha
                    End If
                Next
                If Not Err.Number = 0 Then Exit For
            Next
            Marshal.Copy(tmpBytes, 0, tmpData.Scan0, _bmpWidth * _bmpHeight * 4)
            tmp.UnlockBits(tmpData)
        End If
 
        e.Graphics.DrawImage(tmp, 0, 0, Me.ClientRectangle.Width, Me.ClientRectangle.Height)
 
        If Not Err.Number = 0 Then Debug.WriteLine("WaterEffectControl_Paint: " & Err.Description)
        If Not IsNothing(tmp) Then tmp.Dispose()
    End Sub
 
    Private Sub ProcessWaves()
        Dim newBuffer As Integer = If((_activeBuffer = 0), 1, 0)
        Dim wavesFound As Boolean = False
 
        If newBuffer < 0 Then newBuffer = 1
        On Error Resume Next
        For x As Integer = 1 To _waveWidth - 2
            For y As Integer = 1 To _waveHeight - 2
                _waves(x, y, newBuffer) = CShort((((_waves(x - 1, y - 1, _activeBuffer) + _waves(x, y - 1, _activeBuffer) + _waves(x + 1, y - 1, _activeBuffer) + _waves(x - 1, y, _activeBuffer) + _waves(x + 1, y, _activeBuffer) + _waves(x - 1, y + 1, _activeBuffer) + _waves(x, y + 1, _activeBuffer) + _waves(x + 1, y + 1, _activeBuffer)) >> 2) - _waves(x, y, newBuffer)))
                'damping
                If _waves(x, y, newBuffer) <> 0 Then
                    _waves(x, y, newBuffer) -= CShort((_waves(x, y, newBuffer) >> 4))
                    wavesFound = True
                End If
                If Not Err.Number = 0 Then Exit For
            Next
            If Not Err.Number = 0 Then Exit For
        Next
        _weHaveWaves = wavesFound
        _activeBuffer = newBuffer
    End Sub
 
    Private Sub PutDrop(ByVal x As Integer, ByVal y As Integer, ByVal height As Short)
        _weHaveWaves = True
        Dim radius As Integer = 20
        Dim dist As Double
        On Error Resume Next
        For i As Integer = -radius To radius
            For j As Integer = -radius To radius
                If ((x + i >= 0) AndAlso (x + i < _waveWidth - 1)) AndAlso ((y + j >= 0) AndAlso (y + j < _waveHeight - 1)) Then
                    dist = Math.Sqrt(i * i + j * j)
                    If dist < radius Then
                        _waves(x + i, y + j, _activeBuffer) = CShort((Math.Cos(dist * Math.PI / radius) * height))
                    End If
                End If
                If Not Err.Number = 0 Then Return
            Next
            If Not Err.Number = 0 Then Return
        Next
    End Sub
 
    Private Sub WaterEffectControl_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs)
        On Error Resume Next
        If Not __IsBusy Then
            Dim realX As Integer = CInt(((e.X / CDbl(Me.ClientRectangle.Width)) * _waveWidth))
            Dim realY As Integer = CInt(((e.Y / CDbl(Me.ClientRectangle.Height)) * _waveHeight))
            If Not Err.Number = 0 Then Return
            PutDrop(realX, realY, 200)
        End If
        If Not tmrBalance.Enabled Then tmrBalance.Start()
    End Sub
 
#Region "Properties"
    Public Property ImageBitmap() As Bitmap
        Get
            Return _bmp
        End Get
        Set(ByVal value As Bitmap)
            _bmp = value
            If IsNothing(_bmp) Then
                effectTimer.Stop()
                tmrBalance.Stop()
                Return
            Else
                effectTimer.Start()
                __IsBusy = False
            End If
            _bmpHeight = _bmp.Height
            _bmpWidth = _bmp.Width
 
            _waveWidth = _bmpWidth >> _scale
            _waveHeight = _bmpHeight >> _scale
            _waves = New Int16(_waveWidth - 1, _waveHeight - 1, 1) {}
 
            _bmpBytes = New Byte(_bmpWidth * _bmpHeight * 4 - 1) {}
            _bmpBitmapData = _bmp.LockBits(New Rectangle(0, 0, _bmpWidth, _bmpHeight), ImageLockMode.ReadWrite, PixelFormat.Format32bppArgb)
            Marshal.Copy(_bmpBitmapData.Scan0, _bmpBytes, 0, _bmpWidth * _bmpHeight * 4)
        End Set
    End Property
    Public Shadows Property Scale() As Integer
        Get
            Return _scale
        End Get
        Set(ByVal value As Integer)
            _scale = value
        End Set
    End Property
#End Region

End Class

Решение задачи: «Эффект воды»

textual
                            Листинг программы 
                        

                            using System;
using System.Collections;
using System.Drawing;
using System.Drawing.Imaging;
using System.Runtime.InteropServices;
using System.Windows.Forms;
 
namespace WaterEffectDemo
{
    /// <summary>
    /// 
    /// </summary>
    public class WaterEffectControl : System.Windows.Forms.Panel
    {
        private System.Windows.Forms.Timer effectTimer;
        private System.ComponentModel.IContainer components;
 
        private Bitmap      _bmp;
        private short[,,]   _waves;
        private int         _waveWidth;
        private int         _waveHeight;
        private int         _activeBuffer = 0;
        private bool        _weHaveWaves;
        private int         _bmpHeight,_bmpWidth;
        private byte[]      _bmpBytes;      
        private BitmapData  _bmpBitmapData;     
        private int         _scale;
    
 
        private void InitializeComponent()
        {
            this.components = new System.ComponentModel.Container();
            this.effectTimer = new System.Windows.Forms.Timer(this.components);
            // 
            // effectTimer
            // 
            this.effectTimer.Tick += new System.EventHandler(this.effectTimer_Tick);
            // 
            // WaterEffectControl
            // 
            this.Paint += new System.Windows.Forms.PaintEventHandler(this.WaterEffectControl_Paint);
            this.MouseMove += new System.Windows.Forms.MouseEventHandler(this.WaterEffectControl_MouseMove);
 
        }
    
        public WaterEffectControl()
        {
            InitializeComponent();
            effectTimer.Enabled = true;
            effectTimer.Interval = 50;
            SetStyle(ControlStyles.UserPaint, true);
            SetStyle(ControlStyles.AllPaintingInWmPaint, true);
            SetStyle(ControlStyles.DoubleBuffer, true);
            this.BackColor = Color.White;
            _weHaveWaves = false;           
            _scale = 1;
            
        }
 
        public WaterEffectControl(Bitmap bmp) : this()
        {
            this.ImageBitmap = bmp;         
        }
 
        protected override void Dispose( bool disposing )
        {
            _bmp.UnlockBits(_bmpBitmapData);
            if( disposing )
            {
                if (components != null) 
                {
                    components.Dispose();
                }
            }
            base.Dispose( disposing );
        }
 
        /// <summary>
        /// Timer handler
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void effectTimer_Tick(object sender, System.EventArgs e)
        {   
 
            if(_weHaveWaves)
            {
                Invalidate();
 
                ProcessWaves();
 
            }
        }
 
        /// <summary>
        /// Paint handler
        /// 
        /// Calculates the final effect-image out of
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void WaterEffectControl_Paint(object sender, System.Windows.Forms.PaintEventArgs e)
        {
    
            using(Bitmap tmp = (Bitmap)_bmp.Clone())
            {
                
                int xOffset, yOffset;
                byte alpha;
            
                if(_weHaveWaves)
                {
                    BitmapData tmpData =  tmp.LockBits(new Rectangle(0,0,_bmpWidth,_bmpHeight), ImageLockMode.ReadWrite, PixelFormat.Format32bppArgb);
                    
                    byte[] tmpBytes = new Byte[_bmpWidth*_bmpHeight*4];
 
                    Marshal.Copy(tmpData.Scan0,tmpBytes,0,_bmpWidth*_bmpHeight*4);
                    
                    for(int x=1; x<_bmpWidth -1; x++)
                    {
                        for(int y=1; y<_bmpHeight -1; y++)
                        {
                            int waveX = (int)x >> _scale;
                            int waveY = (int)y >> _scale;
 
                            //check bounds
                            if(waveX <= 0) waveX = 1;
                            if(waveY <= 0) waveY = 1;
                            if(waveX >= _waveWidth-1) waveX = _waveWidth-2;
                            if(waveY >= _waveHeight-1) waveY = _waveHeight-2;
 
                            //this gives us the effect of water breaking the light
                            xOffset = (_waves[waveX-1,waveY,_activeBuffer] -_waves[waveX+1,waveY,_activeBuffer]) >> 3;
                            yOffset = (_waves[waveX,waveY-1,_activeBuffer] -_waves[waveX,waveY+1,_activeBuffer]) >> 3;
 
                            if((xOffset != 0) || (yOffset != 0))
                            {
                                //check bounds
                                if(x+xOffset >= _bmpWidth-1)    xOffset = _bmpWidth - x - 1;
                                if(y+yOffset >= _bmpHeight-1)   yOffset = _bmpHeight - y - 1;
                                if(x+xOffset < 0)   xOffset = -x;
                                if(y+yOffset < 0)   yOffset = -y;
                                
                                //generate alpha
                                alpha = (byte)(200-xOffset);
                                if(alpha < 0) alpha = 0;
                                if(alpha > 255) alpha = 254;
 
                                //set colors
                                tmpBytes[4*(x + y*_bmpWidth)]       = _bmpBytes[4*(x+xOffset + (y+yOffset)*_bmpWidth)];
                                tmpBytes[4*(x + y*_bmpWidth) + 1]   = _bmpBytes[4*(x+xOffset + (y+yOffset)*_bmpWidth) + 1];
                                tmpBytes[4*(x + y*_bmpWidth) + 2]   = _bmpBytes[4*(x+xOffset + (y+yOffset)*_bmpWidth) + 2];
                                tmpBytes[4*(x + y*_bmpWidth) + 3]   = alpha;
                                
                            }
 
                        }
                    }
 
                    //copy data back
                    Marshal.Copy(tmpBytes, 0, tmpData.Scan0, _bmpWidth*_bmpHeight*4);
                    tmp.UnlockBits(tmpData);
                    
                }
 
                e.Graphics.DrawImage(tmp,0,0,this.ClientRectangle.Width, this.ClientRectangle.Height);
                
            }
            
        }
 
        /// <summary>
        /// This is the method that actually does move the waves around and simulates the
        /// behaviour of water.
        /// </summary>
        private void ProcessWaves()
        {
            int newBuffer = (_activeBuffer == 0) ? 1 : 0;
            bool wavesFound = false;
 
            for(int x=1; x<_waveWidth -1; x++)
            {
                for(int y=1; y<_waveHeight -1; y++)
                {
                    _waves[x,y,newBuffer] = (short)(
                                            ((_waves[x-1,y-1,_activeBuffer] +
                                            _waves[x,y-1,_activeBuffer] +
                                            _waves[x+1,y-1,_activeBuffer] +
                                            _waves[x-1,y,_activeBuffer] +
                                            _waves[x+1,y,_activeBuffer] +
                                            _waves[x-1,y+1,_activeBuffer] +
                                            _waves[x,y+1,_activeBuffer] +
                                            _waves[x+1,y+1,_activeBuffer]) >> 2) - _waves[x,y,newBuffer]);
                    
                    //damping
                    if(_waves[x,y,newBuffer] != 0)
                    {
                        _waves[x,y,newBuffer] -= (short)(_waves[x,y,newBuffer] >> 4);                   
                        wavesFound = true;
                    }
                    
                    
                }
            }
 
            _weHaveWaves = wavesFound;
            _activeBuffer = newBuffer;
 
        }
 
 
        /// <summary>
        /// This function is used to start a wave by simulating a round drop
        /// </summary>
        /// <param name="x">x position of the drop</param>
        /// <param name="y">y position of the drop</param>
        /// <param name="height">Height position of the drop</param>
        private void PutDrop(int x, int y, short height)
        {
            _weHaveWaves = true;
            int radius = 20;
            double dist;
 
            for(int i = -radius; i<=radius; i++)
            {
                for(int j = -radius; j<=radius; j++)
                {
                    if(((x+i>=0) && (x+i<_waveWidth-1)) && ((y+j>=0) && (y+j<_waveHeight-1)))
                    {
                        dist = Math.Sqrt(i*i +j*j);
                        if(dist<radius)
                            _waves[x+i,y+j,_activeBuffer] = (short)(Math.Cos(dist*Math.PI  / radius) * height);
                    }
                }
            }
        }
 
        /// <summary>
        /// The MouseMove handler.
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void WaterEffectControl_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
        {
            if(e.Button == MouseButtons.Left)
            {
                int realX = (int)((e.X / (double)this.ClientRectangle.Width)*_waveWidth);
                int realY = (int)((e.Y / (double)this.ClientRectangle.Height)*_waveHeight);
                PutDrop(realX,realY,200);
            }
        }
 
 
        #region Properties
        /// <summary>
        /// Our background image
        /// </summary>
        public Bitmap ImageBitmap
        {
            get { return _bmp; }
            set 
            {
                _bmp = value;
                _bmpHeight = _bmp.Height;
                _bmpWidth = _bmp.Width;
 
                _waveWidth = _bmpWidth >> _scale;
                _waveHeight = _bmpHeight  >> _scale;
                _waves = new Int16[_waveWidth,_waveHeight, 2];                              
 
                _bmpBytes = new Byte[_bmpWidth*_bmpHeight*4];
                _bmpBitmapData =  _bmp.LockBits(new Rectangle(0,0,_bmpWidth,_bmpHeight), ImageLockMode.ReadWrite, PixelFormat.Format32bppArgb);
                Marshal.Copy(_bmpBitmapData.Scan0,_bmpBytes,0,_bmpWidth*_bmpHeight*4);
            }
        }
 
        /// <summary>
        /// The scale of the wave matrix compared to the size of the image.
        /// Use it for large images to reduce processor load.
        /// 
        /// 0 : wave resolution is the same than image resolution
        /// 1 : wave resolution is half the image resolution
        /// ...and so on
        /// </summary>
        public int Scale
        {
            get { return _scale; }
            set { _scale = value;   }
        }
        #endregion
    }
}
                        