src/context/CoverBling.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by Mark Kretschmann <kretschmann@kde.org>          *
   3  *                                                                         *
   4  *   This program is free software; you can redistribute it and/or modify  *
   5  *   it under the terms of the GNU General Public License as published by  *
   6  *   the Free Software Foundation; either version 2 of the License, or     *
   7  *   (at your option) any later version.                                   *
   8  *                                                                         *
   9  *   This program is distributed in the hope that it will be useful,       *
  10  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  12  *   GNU General Public License for more details.                          *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU General Public License     *
  15  *   along with this program; if not, write to the                         *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.          *
  18  ***************************************************************************/
  19
  20 #define DEBUG_PREFIX "CoverBling"
  21
  22 #include "debug.h"
  23 #include "CoverBling.h"
  24
  25 #include <math.h>
  26
  27 #include <QtOpenGL>
  28 #include <KStandardDirs>
  29
  30 #define TEXTURE_SIZE QSize( 256, 256 )
  31
  32
  33 CoverBling::CoverBling( QWidget* parent )
  34         : QGLWidget( QGLFormat(QGL::DepthBuffer|QGL::SampleBuffers|QGL::AlphaChannel|QGL::DoubleBuffer), parent )
  35         , m_xOffset( 0.0 )
  36         , m_zOffset( M_PI / 2 )
  37 {
  38     DEBUG_BLOCK
  39
  40     setFixedHeight( 200 );
  41
  42     m_coverPaths << "amarok/images/album_cover_1.jpg";
  43     m_coverPaths << "amarok/images/album_cover_2.jpg";
  44     m_coverPaths << "amarok/images/album_cover_3.jpg";
  45     m_coverPaths << "amarok/images/album_cover_4.jpg";
  46     m_coverPaths << "amarok/images/album_cover_5.jpg";
  47     m_coverPaths << "amarok/images/album_cover_6.jpg";
  48     m_coverPaths << "amarok/images/album_cover_7.jpg";
  49     m_coverPaths << "amarok/images/album_cover_8.jpg";
  50     m_coverPaths << "amarok/images/album_cover_9.jpg";
  51
  52     QTimer* timer = new QTimer( this );
  53     connect( timer, SIGNAL( timeout() ), this, SLOT( updateGL() ) );
  54     timer->start( 20 ); //50fps
  55 }
  56
  57 void
  58 CoverBling::initializeGL() //reimplemented
  59 {
  60     DEBUG_BLOCK
  61
  62     //generate all textures
  63     foreach( QString path, m_coverPaths ) {
  64         QImage image( KStandardDirs().findResource( "data", path ) );
  65         image = image.scaled( TEXTURE_SIZE, Qt::KeepAspectRatio, Qt::SmoothTransformation );
  66         m_textureIds << bindTexture( image );
  67     }
  68
  69     glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
  70     glShadeModel(GL_SMOOTH);
  71     qglClearColor( Qt::black );
  72     glEnable( GL_MULTISAMPLE ); //enable anti aliasing
  73     glEnable( GL_DEPTH_TEST );
  74     glDepthMask( true );
  75
  76     //Display list for drawing a textured rectangle
  77     m_texturedRectList = glGenLists( 1 );
  78     glNewList( m_texturedRectList, GL_COMPILE );
  79         glBegin (GL_QUADS);
  80             glTexCoord2f (0.0, 0.0);
  81             glColor3f( 1.0, 1.0, 1.0 );
  82             glVertex3f (-1.0, -1.0, -1.0);
  83             glTexCoord2f (1.0, 0.0);
  84             glColor3f( 0.1, 0.1, 0.1 );
  85             glVertex3f (1.0, -1.0, -1.0);
  86             glTexCoord2f (1.0, 1.0);
  87             glColor3f( 0.1, 0.1, 0.1 );
  88             glVertex3f (1.0, 1.0, -1.0);
  89             glTexCoord2f (0.0, 1.0);
  90             glColor3f( 1.0, 1.0, 1.0 );
  91             glVertex3f (-1.0, 1.0, -1.0);
  92         glEnd ();
  93         //glDisable( GL_DEPTH_TEST );
  94     glEndList();
  95
  96     //Display list for drawing reflection of the textured rectangle
  97     m_texturedRectReflectedList = glGenLists( 1 );
  98     glNewList( m_texturedRectReflectedList, GL_COMPILE );
  99         glTranslatef( 0.0, -2.0, 0.0 );
 100         glScalef( 1.0, -1.0, 1.0 );
 101
 102         glEnable( GL_BLEND );
 103         //glBlendFunc( GL_SRC_COLOR, GL_ONE_MINUS_SRC_COLOR );
 104         glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
 105
 106         glBegin (GL_QUADS);
 107             glTexCoord2f (0.0, 0.0);
 108             glColor4f( 1.0, 1.0, 1.0, 0.3 );
 109             glVertex3f (-1.0, -1.0, -1.0);
 110             glColor4f( 1.0, 1.0, 1.0, 0.3 - 0.15 );
 111             glTexCoord2f (1.0, 0.0);
 112             glVertex3f (1.0, -1.0, -1.0);
 113             glColor4f( 1.0, 1.0, 1.0, 0.02 - 0.15 );
 114             glTexCoord2f (1.0, 1.0);
 115             glVertex3f (1.0, 1.0, -1.0);
 116             glColor4f( 1.0, 1.0, 1.0, 0.02 );
 117             glTexCoord2f (0.0, 1.0);
 118             glVertex3f (-1.0, 1.0, -1.0);
 119         glEnd ();
 120
 121         glDisable( GL_BLEND );
 122     glEndList();
 123 }
 124
 125 void
 126 CoverBling::resizeGL( int width, int height ) //reimplemented
 127 {
 128     DEBUG_BLOCK
 129
 130     glViewport( 0, 0, (GLint)width, (GLint)height );
 131     glMatrixMode(GL_PROJECTION);
 132     glLoadIdentity();
 133     //glFrustum( -0.5f, 0.5f, -0.5f, 0.5f, 0.3f, 4.5f );
 134     setPerspective();
 135     glMatrixMode(GL_MODELVIEW);
 136 }
 137
 138 void
 139 CoverBling::setPerspective()
 140 {
 141     gluPerspective( 30, (double)width() / height(), 1.0, 20.0 );
 142 }
 143
 144 void
 145 CoverBling::paintGL() //reimplemented
 146 {
 147     glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
 148
 149     const QPoint mousePos = mapFromGlobal( QCursor::pos() );
 150     draw( objectAtPosition( mousePos ) );
 151 }
 152
 153 void
 154 CoverBling::draw( GLuint selected )
 155 {
 156     GLuint objectName = 1;
 157
 158     glMatrixMode( GL_MODELVIEW );
 159     glLoadIdentity();
 160     glRotatef( 10, 1.0, 0.0, 0.0 ); //Rotate whole scene around X axis; simulates camera tilt
 161     glScalef( 1.0, 1.0, 6.0 );
 162
 163     //draw the ground
 164     //glBegin( GL_POLYGON );
 165     //    glColor3f( 0.0, 0.0, 0.5 );
 166     //    glVertex3f (-3.0, -1.0, -2.0);
 167     //    glColor3f( 1.0, 0.0, 0.5 );
 168     //    glVertex3f (3.0, -1.0, -2.0);
 169     //    glColor3f( 0.0, 1.0, 0.5 );
 170     //    glVertex3f (3.0, -1.0, 2.0);
 171     //    glColor3f( 0.0, 0.0, 1.5 );
 172     //    glVertex3f (-3.0, -1.0, 2.0);
 173     //glEnd();
 174
 175     glColor3f( 1.0, 1.0, 1.0 ); //reset color
 176     glEnable( GL_TEXTURE_2D);
 177
 178     float xoffset = -5.5;
 179     float yoffset = -0.6;
 180     float zoffset = -1.1;
 181
 182     foreach( GLuint id, m_textureIds ) {
 183         glBindTexture( GL_TEXTURE_2D, id );
 184         glPushMatrix();
 185             const float xsin = sin( xoffset );
 186             const float zsin = sin( zoffset );
 187             xoffset += 1.0;
 188             zoffset += 0.1;
 189             glTranslatef( xoffset, yoffset, zoffset );
 190             glRotatef( 8, 0.0, 1.0, 0.0 );
 191
 192             //draw the cover
 193             if( objectName == selected )
 194                 glColor3f( 1.0, 0.0, 0.0 );
 195             glLoadName( objectName++ );
 196             glCallList( m_texturedRectList );
 197             glColor4f( 1.0, 1.0, 1.0, 1.0 );
 198
 199             //draw reflection on the ground
 200             glLoadName( 0 );
 201             glPushMatrix();
 202                 glCallList( m_texturedRectReflectedList );
 203             glPopMatrix();
 204         glPopMatrix();
 205         glColor4f( 1.0, 1.0, 1.0, 1.0 );
 206     }
 207
 208     glDisable( GL_TEXTURE_2D);
 209 }
 210
 211 GLuint
 212 CoverBling::objectAtPosition( const QPoint& pos )
 213 {
 214     // this is the same as in every OpenGL picking example
 215     const int MaxSize = 512; // see below for an explanation on the buffer content
 216     GLuint buffer[MaxSize];
 217     GLint viewport[4];
 218
 219     glGetIntegerv(GL_VIEWPORT, viewport);
 220     glSelectBuffer(MaxSize, buffer);
 221     // enter select mode
 222     glRenderMode(GL_SELECT);
 223
 224     glInitNames();
 225     glPushName(0);
 226
 227     glMatrixMode(GL_PROJECTION);
 228     glPushMatrix();
 229         glLoadIdentity();
 230         gluPickMatrix((GLdouble)pos.x(), (GLdouble)(viewport[3] - pos.y()), 5.0, 5.0, viewport);
 231         setPerspective();
 232         draw();
 233         glMatrixMode(GL_PROJECTION);
 234     glPopMatrix();
 235
 236     const int hits = glRenderMode( GL_RENDER );
 237     if ( !hits )
 238         return 0;
 239
 240     //determine object with the lowest Z value
 241     uint hitZValue = UINT_MAX;
 242     uint hit       = UINT_MAX;
 243     for( int i = 0; i < hits; i++ ) {
 244         if( buffer[(i*4)+1] < hitZValue ) {
 245             hit       = buffer[(i*4)+3];
 246             hitZValue = buffer[(i*4)+1];
 247         }
 248     }
 249
 250     // return the name of the clicked surface
 251     return hit;
 252 }
 253
 254
 255 #include "CoverBling.moc"
 256