simgear/canvas/ODGauge.cxx

   1 // Owner Drawn Gauge helper class
   2 //
   3 // Written by Harald JOHNSEN, started May 2005.
   4 //
   5 // Copyright (C) 2005  Harald JOHNSEN
   6 //
   7 // Ported to OSG by Tim Moore - Jun 2007
   8 //
   9 // Heavily modified to be usable for the 2d Canvas by Thomas Geymayer - April 2012
  10 // Supports now multisampling/mipmapping, usage of the stencil buffer and placing
  11 // the texture in the scene by certain filter criteria
  12 //
  13 // This library is free software; you can redistribute it and/or
  14 // modify it under the terms of the GNU Library General Public
  15 // License as published by the Free Software Foundation; either
  16 // version 2 of the License, or (at your option) any later version.
  17 //
  18 // This library is distributed in the hope that it will be useful,
  19 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21 // Library General Public License for more details.
  22 //
  23 // You should have received a copy of the GNU Library General Public
  24 // License along with this library; if not, write to the Free Software
  25 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA
  26
  27 #ifdef HAVE_CONFIG_H
  28 #  include <simgear_config.h>
  29 #endif
  30
  31 #include "ODGauge.hxx"
  32 #include "CanvasSystemAdapter.hxx"
  33
  34 #include <simgear/debug/logstream.hxx>
  35 #include <simgear/scene/util/RenderConstants.hxx>
  36
  37 #include <osg/Texture2D>
  38 #include <osg/AlphaFunc>
  39 #include <osg/BlendFunc>
  40 #include <osg/Camera>
  41 #include <osg/Matrix>
  42 #include <osg/PolygonMode>
  43 #include <osg/ShadeModel>
  44 #include <osg/StateSet>
  45 #include <osg/FrameBufferObject> // for GL_DEPTH_STENCIL_EXT on Windows
  46 #include <osgUtil/RenderBin>
  47
  48 #include <cassert>
  49
  50 namespace simgear
  51 {
  52 namespace canvas
  53 {
  54
  55   class PreOrderBin:
  56     public osgUtil::RenderBin
  57   {
  58     public:
  59
  60       PreOrderBin()
  61       {}
  62       PreOrderBin( const RenderBin& rhs,
  63                    const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY ):
  64         RenderBin(rhs, copyop)
  65       {}
  66
  67       virtual osg::Object* cloneType() const
  68       {
  69         return new PreOrderBin();
  70       }
  71       virtual osg::Object* clone(const osg::CopyOp& copyop) const
  72       {
  73         return new PreOrderBin(*this,copyop);
  74       }
  75       virtual bool isSameKindAs(const osg::Object* obj) const
  76       {
  77         return dynamic_cast<const PreOrderBin*>(obj) != 0L;
  78       }
  79       virtual const char* className() const
  80       {
  81         return "PreOrderBin";
  82       }
  83
  84       virtual void sort()
  85       {
  86         // Do not sort to keep traversal order...
  87       }
  88   };
  89
  90   OSG_INIT_SINGLETON_PROXY(
  91     PreOrderBinProxy,
  92     (osgUtil::RenderBin::addRenderBinPrototype("PreOrderBin", new PreOrderBin))
  93   );
  94
  95   //----------------------------------------------------------------------------
  96   ODGauge::ODGauge():
  97     _size_x( -1 ),
  98     _size_y( -1 ),
  99     _view_width( -1 ),
 100     _view_height( -1 ),
 101     _flags(0),
 102     _coverage_samples( 0 ),
 103     _color_samples( 0 )
 104   {
 105
 106   }
 107
 108   //----------------------------------------------------------------------------
 109   ODGauge::~ODGauge()
 110   {
 111     clear();
 112   }
 113
 114   //----------------------------------------------------------------------------
 115   void ODGauge::setSystemAdapter(const SystemAdapterPtr& system_adapter)
 116   {
 117     _system_adapter = system_adapter;
 118   }
 119
 120   //----------------------------------------------------------------------------
 121   void ODGauge::setSize(int size_x, int size_y)
 122   {
 123     _size_x = size_x;
 124     _size_y = size_y < 0 ? size_x : size_y;
 125
 126     if( serviceable() )
 127       reinit();
 128     else if( texture )
 129       texture->setTextureSize(_size_x, _size_y);
 130   }
 131
 132   //----------------------------------------------------------------------------
 133   void ODGauge::setViewSize(int width, int height)
 134   {
 135     _view_width = width;
 136     _view_height = height < 0 ? width : height;
 137
 138     if( camera )
 139       updateCoordinateFrame();
 140   }
 141
 142   //----------------------------------------------------------------------------
 143   osg::Vec2s ODGauge::getViewSize() const
 144   {
 145     return osg::Vec2s(_view_width, _view_height);
 146   }
 147
 148   //----------------------------------------------------------------------------
 149   void ODGauge::useImageCoords(bool use)
 150   {
 151     if( updateFlag(USE_IMAGE_COORDS, use) && texture )
 152       updateCoordinateFrame();
 153   }
 154
 155   //----------------------------------------------------------------------------
 156   void ODGauge::useStencil(bool use)
 157   {
 158     if( updateFlag(USE_STENCIL, use) && texture )
 159       updateStencil();
 160   }
 161
 162   //----------------------------------------------------------------------------
 163   void ODGauge::useAdditiveBlend(bool use)
 164   {
 165     if( updateFlag(USE_ADDITIVE_BLEND, use) && camera )
 166       updateBlendMode();
 167   }
 168
 169   //----------------------------------------------------------------------------
 170   void ODGauge::setSampling( bool mipmapping,
 171                              int coverage_samples,
 172                              int color_samples )
 173   {
 174     if(    !updateFlag(USE_MIPMAPPING, mipmapping)
 175         && _coverage_samples == coverage_samples
 176         && _color_samples == color_samples )
 177       return;
 178
 179     if( color_samples > coverage_samples )
 180     {
 181       SG_LOG
 182       (
 183         SG_GL,
 184         SG_WARN,
 185         "ODGauge::setSampling: color_samples > coverage_samples not allowed!"
 186       );
 187       color_samples = coverage_samples;
 188     }
 189
 190     _coverage_samples = coverage_samples;
 191     _color_samples = color_samples;
 192
 193     updateSampling();
 194   }
 195
 196   //----------------------------------------------------------------------------
 197   void ODGauge::setRender(bool render)
 198   {
 199     // Only the far camera should trigger this texture to be rendered.
 200     camera->setNodeMask(render ? simgear::BACKGROUND_BIT : 0);
 201   }
 202
 203   //----------------------------------------------------------------------------
 204   bool ODGauge::serviceable() const
 205   {
 206     return _flags & AVAILABLE;
 207   }
 208
 209   //----------------------------------------------------------------------------
 210   void ODGauge::allocRT(osg::NodeCallback* camera_cull_callback)
 211   {
 212     camera = new osg::Camera;
 213     camera->setDataVariance(osg::Object::DYNAMIC);
 214     camera->setReferenceFrame(osg::Transform::ABSOLUTE_RF);
 215     camera->setRenderOrder(osg::Camera::PRE_RENDER);
 216     camera->setClearColor(osg::Vec4(0.0f, 0.0f, 0.0f , 0.0f));
 217     camera->setClearStencil(0);
 218     camera->setRenderTargetImplementation( osg::Camera::FRAME_BUFFER_OBJECT,
 219                                                osg::Camera::FRAME_BUFFER );
 220
 221     if( camera_cull_callback )
 222       camera->setCullCallback(camera_cull_callback);
 223
 224     setRender(true);
 225     updateCoordinateFrame();
 226     updateStencil();
 227
 228     osg::StateSet* stateSet = camera->getOrCreateStateSet();
 229     stateSet->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
 230     stateSet->setMode(GL_CULL_FACE, osg::StateAttribute::OFF);
 231     stateSet->setMode(GL_FOG, osg::StateAttribute::OFF);
 232     stateSet->setMode(GL_DEPTH_TEST, osg::StateAttribute::OFF);
 233     stateSet->setAttributeAndModes(
 234       new osg::PolygonMode( osg::PolygonMode::FRONT_AND_BACK,
 235                             osg::PolygonMode::FILL ),
 236       osg::StateAttribute::ON );
 237     stateSet->setAttributeAndModes(
 238       new osg::AlphaFunc(osg::AlphaFunc::GREATER, 0.001f),
 239       osg::StateAttribute::ON );
 240     stateSet->setAttribute(new osg::ShadeModel(osg::ShadeModel::FLAT));
 241
 242     if( !texture )
 243     {
 244       texture = new osg::Texture2D;
 245       texture->setResizeNonPowerOfTwoHint(false);
 246       texture->setTextureSize(_size_x, _size_y);
 247       texture->setInternalFormat(GL_RGBA);
 248     }
 249
 250     updateSampling();
 251     updateBlendMode();
 252
 253     if( _system_adapter )
 254       _system_adapter->addCamera(camera.get());
 255
 256     _flags |= AVAILABLE;
 257   }
 258
 259   //----------------------------------------------------------------------------
 260   void ODGauge::reinit()
 261   {
 262     osg::NodeCallback* cull_callback = camera ? camera->getCullCallback() : 0;
 263     clear();
 264     allocRT(cull_callback);
 265   }
 266
 267   //----------------------------------------------------------------------------
 268   void ODGauge::clear()
 269   {
 270     if( camera.valid() && _system_adapter )
 271       _system_adapter->removeCamera(camera.get());
 272     camera.release();
 273     texture.release();
 274
 275     _flags &= ~AVAILABLE;
 276   }
 277
 278   //----------------------------------------------------------------------------
 279   bool ODGauge::updateFlag(Flags flag, bool enable)
 280   {
 281     if( bool(_flags & flag) == enable )
 282       return false;
 283
 284     _flags ^= flag;
 285     return true;
 286   }
 287
 288   //----------------------------------------------------------------------------
 289   void ODGauge::updateCoordinateFrame()
 290   {
 291     assert( camera );
 292
 293     if( _view_width < 0 )
 294       _view_width = _size_x;
 295     if( _view_height < 0 )
 296       _view_height = _size_y;
 297
 298     camera->setViewport(0, 0, _size_x, _size_y);
 299
 300     if( _flags & USE_IMAGE_COORDS )
 301       camera->setProjectionMatrix(
 302         osg::Matrix::ortho2D(0, _view_width, _view_height, 0)
 303       );
 304     else
 305       camera->setProjectionMatrix(
 306         osg::Matrix::ortho2D( -_view_width/2.,  _view_width/2.,
 307                               -_view_height/2., _view_height/2. )
 308       );
 309   }
 310
 311   //----------------------------------------------------------------------------
 312   void ODGauge::updateStencil()
 313   {
 314     assert( camera );
 315
 316     GLbitfield mask = GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT;
 317
 318     if( _flags & USE_STENCIL )
 319     {
 320       camera->attach( osg::Camera::PACKED_DEPTH_STENCIL_BUFFER,
 321                        GL_DEPTH_STENCIL_EXT );
 322       mask |= GL_STENCIL_BUFFER_BIT;
 323     }
 324     else
 325     {
 326       camera->detach(osg::Camera::PACKED_DEPTH_STENCIL_BUFFER);
 327     }
 328
 329     camera->setClearMask(mask);
 330   }
 331
 332   //----------------------------------------------------------------------------
 333   void ODGauge::updateSampling()
 334   {
 335     assert( camera );
 336     assert( texture );
 337
 338     texture->setFilter(
 339       osg::Texture2D::MIN_FILTER,
 340       (_flags & USE_MIPMAPPING) ? osg::Texture2D::LINEAR_MIPMAP_LINEAR
 341                                 : osg::Texture2D::LINEAR
 342     );
 343     camera->attach(
 344       osg::Camera::COLOR_BUFFER,
 345       texture.get(),
 346       0, 0,
 347       _flags & USE_MIPMAPPING,
 348       _coverage_samples,
 349       _color_samples
 350     );
 351   }
 352
 353   //----------------------------------------------------------------------------
 354   void ODGauge::updateBlendMode()
 355   {
 356     assert( camera );
 357
 358     camera->getOrCreateStateSet()
 359       ->setAttributeAndModes
 360       (
 361         (_flags & USE_ADDITIVE_BLEND)
 362           ? new osg::BlendFunc( osg::BlendFunc::SRC_ALPHA,
 363                                 osg::BlendFunc::ONE_MINUS_SRC_ALPHA,
 364                                 osg::BlendFunc::ONE,
 365                                 osg::BlendFunc::ONE )
 366           : new osg::BlendFunc( osg::BlendFunc::SRC_ALPHA,
 367                                 osg::BlendFunc::ONE_MINUS_SRC_ALPHA )
 368       );
 369   }
 370
 371 } // namespace canvas
 372 } // namespace simgear