workspace/kwin/effects/test/demo_liquid.cpp

   1 /********************************************************************
   2  KWin - the KDE window manager
   3  This file is part of the KDE project.
   4
   5 Copyright (C) 2007 Rivo Laks <rivolaks@hot.ee>
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 *********************************************************************/
  20
  21 #include "demo_liquid.h"
  22
  23 #include <kwinglutils.h>
  24
  25
  26
  27 #include <kdebug.h>
  28 #include <assert.h>
  29
  30
  31 namespace KWin
  32 {
  33
  34 KWIN_EFFECT( demo_liquid, LiquidEffect )
  35 KWIN_EFFECT_SUPPORTED( demo_liquid, LiquidEffect::supported() )
  36
  37
  38 LiquidEffect::LiquidEffect() : Effect()
  39     {
  40     mTexture = 0;
  41     mRenderTarget = 0;
  42     mShader = 0;
  43
  44     mTime = 0.0f;
  45     mValid = loadData();
  46     }
  47 LiquidEffect::~LiquidEffect()
  48     {
  49     delete mTexture;
  50     delete mRenderTarget;
  51     delete mShader;
  52     }
  53
  54 bool LiquidEffect::loadData()
  55     {
  56     // If NPOT textures are not supported, use nearest power-of-two sized
  57     //  texture. It wastes memory, but it's possible to support systems without
  58     //  NPOT textures that way
  59     int texw = displayWidth();
  60     int texh = displayHeight();
  61     if( !GLTexture::NPOTTextureSupported() )
  62     {
  63         kWarning( 1212 ) << "NPOT textures not supported, wasting some memory" ;
  64         texw = nearestPowerOfTwo(texw);
  65         texh = nearestPowerOfTwo(texh);
  66     }
  67     // Create texture and render target
  68     mTexture = new GLTexture(texw, texh);
  69     mTexture->setFilter(GL_LINEAR_MIPMAP_LINEAR);
  70     mTexture->setWrapMode(GL_CLAMP);
  71
  72     mRenderTarget = new GLRenderTarget(mTexture);
  73     if( !mRenderTarget->valid() )
  74         return false;
  75
  76     QString fragmentshader =  KGlobal::dirs()->findResource("data", "kwin/liquid.frag");
  77     QString vertexshader =  KGlobal::dirs()->findResource("data", "kwin/liquid.vert");
  78     if(fragmentshader.isEmpty() || vertexshader.isEmpty())
  79     {
  80         kError(1212) << "Couldn't locate shader files" << endl;
  81         return false;
  82     }
  83     mShader = new GLShader(vertexshader, fragmentshader);
  84     if(!mShader->isValid())
  85     {
  86         kError(1212) << "The shader failed to load!" << endl;
  87         return false;
  88     }
  89     mShader->bind();
  90     mShader->setUniform("sceneTex", 0);
  91     mShader->setUniform("textureWidth", (float)texw);
  92     mShader->setUniform("textureHeight", (float)texh);
  93     mShader->unbind();
  94
  95     return true;
  96     }
  97
  98 bool LiquidEffect::supported()
  99     {
 100     return GLRenderTarget::supported() &&
 101             GLShader::fragmentShaderSupported() &&
 102             (effects->compositingType() == OpenGLCompositing);
 103     }
 104
 105
 106 void LiquidEffect::prePaintScreen( ScreenPrePaintData& data, int time )
 107     {
 108     mTime += time / 1000.0f;
 109     if(mValid)
 110         {
 111         data.mask |= PAINT_SCREEN_WITH_TRANSFORMED_WINDOWS;
 112         // Start rendering to texture
 113         effects->pushRenderTarget(mRenderTarget);
 114         }
 115
 116     effects->prePaintScreen(data, time);
 117     }
 118
 119 void LiquidEffect::postPaintScreen()
 120     {
 121     // Call the next effect.
 122     effects->postPaintScreen();
 123
 124     if(mValid)
 125         {
 126         // Disable render texture
 127         assert( effects->popRenderTarget() == mRenderTarget );
 128         mTexture->bind();
 129
 130         // Use the shader
 131         mShader->bind();
 132         mShader->setUniform("time", (float)mTime);
 133
 134         // Render fullscreen quad with screen contents
 135         glBegin(GL_QUADS);
 136             glVertex2f(0.0, displayHeight());
 137             glVertex2f(displayWidth(), displayHeight());
 138             glVertex2f(displayWidth(), 0.0);
 139             glVertex2f(0.0, 0.0);
 140         glEnd();
 141
 142         mShader->unbind();
 143         mTexture->unbind();
 144
 145         // Make sure the animation continues
 146         effects->addRepaintFull();
 147         }
 148
 149     }
 150
 151
 152 } // namespace
 153