src/Utils/MiscUI/WaterEffect.cpp

   1 // TortoiseGit - a Windows shell extension for easy version control
   2
   3 // Copyright (C) 2003-2006 - Stefan Kueng
   4
   5 // This program is free software; you can redistribute it and/or
   6 // modify it under the terms of the GNU General Public License
   7 // as published by the Free Software Foundation; either version 2
   8 // of the License, or (at your option) any later version.
   9
  10 // This program is distributed in the hope that it will be useful,
  11 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 // GNU General Public License for more details.
  14
  15 // You should have received a copy of the GNU General Public License
  16 // along with this program; if not, write to the Free Software Foundation,
  17 // 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 //
  19 #include "stdafx.h"
  20 #include "WaterEffect.h"
  21
  22 #include <math.h>
  23
  24
  25 CWaterEffect::CWaterEffect()
  26 {
  27         m_iBuffer1 = NULL;
  28         m_iBuffer2 = NULL;
  29
  30         m_iWidth = 0;
  31         m_iHeight = 0;
  32
  33         m_iLightModifier = 10;
  34         m_iHpage = 0;
  35         m_iDensity = 2;
  36 }
  37
  38 CWaterEffect::~CWaterEffect()
  39 {
  40         // free memory
  41         if (m_iBuffer1 != NULL)
  42                 delete [] m_iBuffer1;
  43         if (m_iBuffer2 != NULL)
  44                 delete [] m_iBuffer2;
  45
  46         m_iBuffer1 = NULL;
  47         m_iBuffer2 = NULL;
  48 }
  49
  50 void CWaterEffect::Create(int iWidth, int iHeight)
  51 {
  52         if (m_iBuffer1 != NULL)
  53                 delete [] m_iBuffer1;
  54         if (m_iBuffer2 != NULL)
  55                 delete [] m_iBuffer2;
  56
  57         m_iBuffer1 = new int[(iWidth*iHeight)];
  58         m_iBuffer2 = new int[(iWidth*iHeight)];
  59
  60         m_iWidth = iWidth;
  61         m_iHeight = iHeight;
  62
  63         ClearWater();
  64
  65         m_iHpage = 0;
  66
  67 }
  68
  69 void CWaterEffect::Blob(int x, int y, int radius, int height, int page)
  70 {
  71         int rquad;
  72         int cx, cy, cyq;
  73         int left, top, right, bottom;
  74
  75         int *pNew;
  76         int *pOld;
  77
  78         if (page == 0)
  79         {
  80                 pNew = &m_iBuffer1[0];
  81                 pOld = &m_iBuffer2[0];
  82         }
  83         else
  84         {
  85                 pNew = &m_iBuffer2[0];
  86                 pOld = &m_iBuffer1[0];
  87         }
  88
  89         rquad = radius * radius;
  90
  91         if (x<0)
  92                 x = 1 + radius + rand() % (m_iWidth - 2 * radius - 1);
  93         if (y<0)
  94                 y = 1 + radius + rand() % (m_iHeight - 2 * radius - 1);
  95
  96         left = -radius;
  97         right = radius;
  98         top = -radius;
  99         bottom = radius;
 100
 101         // clip edges
 102         if (x - radius < 1)
 103                 left -= (x-radius-1);
 104         if (y - radius < 1)
 105                 top  -= (y-radius-1);
 106         if (x + radius > m_iWidth-1)
 107                 right -= (x+radius-m_iWidth+1);
 108         if (y + radius > m_iHeight-1)
 109                 bottom-= (y+radius-m_iHeight+1);
 110
 111         for(cy = top; cy < bottom; cy++)
 112         {
 113                 cyq = cy*cy;
 114                 for(cx = left; cx < right; cx++)
 115                 {
 116                         if (cx*cx + cyq < rquad)
 117                         {
 118                                 pNew[m_iWidth*(cy+y) + (cx+x)] += height;
 119                         }
 120                 }
 121         }
 122 }
 123
 124 void CWaterEffect::ClearWater()
 125 {
 126         // clear height fields
 127         memset(m_iBuffer1,0, (m_iWidth*m_iHeight)*sizeof(int));
 128         memset(m_iBuffer2,0, (m_iWidth*m_iHeight)*sizeof(int));
 129 }
 130
 131 void CWaterEffect::Render(DWORD* pSrcImage, DWORD* pTargetImage)
 132 {
 133         DrawWater(m_iHpage, m_iLightModifier, pSrcImage, pTargetImage);
 134
 135         CalcWater(m_iHpage, m_iDensity);
 136
 137         //change the field from 0 to 1 and vice versa
 138         m_iHpage ^= 1;
 139
 140 }
 141
 142 void CWaterEffect::CalcWater(int npage, int density)
 143 {
 144         int newh;
 145         int count = m_iWidth + 1;
 146         int *pNew;
 147         int *pOld;
 148
 149         if (npage == 0)
 150         {
 151                 pNew = &m_iBuffer1[0];
 152                 pOld = &m_iBuffer2[0];
 153         }
 154         else
 155         {
 156                 pNew = &m_iBuffer2[0];
 157                 pOld = &m_iBuffer1[0];
 158         }
 159
 160         int x, y;
 161
 162         // a description of the algorithm and an implementation
 163         // in 'pseudocode' can be found here:
 164         // http://freespace.virgin.net/hugo.elias/graphics/x_water.htm
 165         for (y = (m_iHeight-1)*m_iWidth; count < y; count += 2)
 166         {
 167                 for (x = count+m_iWidth-2; count < x; count++)
 168                 {
 169                         // use eight pixels
 170                         newh = ((pOld[count + m_iWidth]
 171                                         + pOld[count - m_iWidth]
 172                                         + pOld[count + 1]
 173                                         + pOld[count - 1]
 174                                         + pOld[count - m_iWidth - 1]
 175                                         + pOld[count - m_iWidth + 1]
 176                                         + pOld[count + m_iWidth - 1]
 177                                         + pOld[count + m_iWidth + 1]
 178                                         ) >> 2 )
 179                                         - pNew[count];
 180
 181                         pNew[count] = newh - (newh >> density);
 182                 }
 183         }
 184 }
 185
 186 void CWaterEffect::SmoothWater(int npage)
 187 {
 188         //flatten and spread the waves
 189         int newh;
 190         int count = m_iWidth + 1;
 191
 192         int *pNew;
 193         int *pOld;
 194
 195         if (npage == 0)
 196         {
 197                 pNew = &m_iBuffer1[0];
 198                 pOld = &m_iBuffer2[0];
 199         }
 200         else
 201         {
 202                 pNew = &m_iBuffer2[0];
 203                 pOld = &m_iBuffer1[0];
 204         }
 205
 206         int x, y;
 207
 208         // a description of the algorithm and an implementation
 209         // in 'pseudocode' can be found here:
 210         // http://freespace.virgin.net/hugo.elias/graphics/x_water.htm
 211         for(y=1; y<m_iHeight-1; y++)
 212         {
 213                 for(x=1; x<m_iWidth-1; x++)
 214                 {
 215                   newh = ((pOld[count + m_iWidth]
 216                                         + pOld[count - m_iWidth]
 217                                         + pOld[count + 1]
 218                                         + pOld[count - 1]
 219                                         + pOld[count - m_iWidth - 1]
 220                                         + pOld[count - m_iWidth + 1]
 221                                         + pOld[count + m_iWidth - 1]
 222                                         + pOld[count + m_iWidth + 1]
 223                                         ) >> 3 )
 224                                         + pNew[count];
 225
 226                   pNew[count] = newh>>1;
 227                   count++;
 228                 }
 229                 count += 2;
 230         }
 231 }
 232
 233 void CWaterEffect::DrawWater(int /*page*/, int /*LightModifier*/, DWORD* pSrcImage, DWORD* pTargetImage)
 234 {
 235         int dx, dy;
 236         int x, y;
 237         DWORD c;
 238
 239         int offset = m_iWidth + 1;
 240         long lIndex;
 241         long lBreak = m_iWidth*m_iHeight;
 242
 243         int *ptr = &m_iBuffer1[0];
 244
 245
 246         for (y = (m_iHeight-1)*m_iWidth; offset < y; offset += 2)
 247         {
 248                 for (x = offset + m_iWidth - 2; offset < x; offset++)
 249                 {
 250                         dx = ptr[offset] - ptr[offset+1];
 251                         dy = ptr[offset] - ptr[offset+m_iWidth];
 252
 253                         lIndex = offset + m_iWidth*(dy>>3) + (dx>>3);
 254                         if (lIndex < lBreak && lIndex > 0)
 255                         {
 256                                 c = pSrcImage[lIndex];
 257                                 c = GetShiftedColor(c,dx);
 258                                 pTargetImage[offset] = c;
 259                         }
 260
 261                         offset++;
 262                         dx = ptr[offset] - ptr[offset+1];
 263                         dy = ptr[offset] - ptr[offset+m_iWidth];
 264
 265                         lIndex = offset + m_iWidth*(dy>>3) + (dx>>3);
 266                         if (lIndex < lBreak && lIndex > 0)
 267                         {
 268                                 c = pSrcImage[lIndex];
 269                                 c = GetShiftedColor(c,dx);
 270                                 pTargetImage[offset] = c;
 271                         }
 272                 }
 273         }
 274 }
 275
 276 COLORREF CWaterEffect::GetShiftedColor(COLORREF color, int shift)
 277 {
 278         long R;
 279         long G;
 280         long B;
 281         int ir;
 282         int ig;
 283         int ib;
 284
 285         R = GetRValue(color)-shift;
 286         G = GetGValue(color)-shift;
 287         B = GetBValue(color)-shift;
 288
 289         ir = (R < 0) ? 0 : (R > 255) ? 255 : R;
 290         ig = (G < 0) ? 0 : (G > 255) ? 255 : G;
 291         ib = (B < 0) ? 0 : (B > 255) ? 255 : B;
 292
 293         return RGB(ir,ig,ib);
 294 }