/* OpenSceneGraph example, osgtessellate. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ /* osgTessellator * - this Tessellator is an extension of the basic one - rather than tessellating * individual polygons, we tessellate the entire geode with multiple contours. * allows for overlapping contours etc. * the Tessellator has new member fuinctions setTessellationType(osgUtil::Tessellator::TESS_TYPE_xxx); tscx->setBoundaryOnly(bool); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_xxx); * for winding rules: See the red book chap 13. */ #include #include #include #include #include #include #include // to tessellate multiple contours class tessellateDemoGeometry : public osg::Geometry, public osgUtil::Tessellator { // We add the Tessellator to the geometry because we want to access the // tessellatable contours again; you can apply a Tessellator to a Geometry // to produce exactly a required tessellation once only, and then // the contours could be discarded since the geometry does not need to be retessellated. public: tessellateDemoGeometry() {}; protected: virtual ~tessellateDemoGeometry() {}; }; osg::Geometry *makePolsTwo (void) { // an example of using current geometry contours to create next tessellation // this polygon disappears once the contour rules make no polygons. tessellateDemoGeometry *gtess= new tessellateDemoGeometry; int i; osg::Vec3Array *coords = new osg::Vec3Array; osg::Vec3Array *nrms = new osg::Vec3Array; osg::Vec2Array *tcs = new osg::Vec2Array; osg::Vec3 nrm(0,-1,0); static GLdouble quadstrip[8][3] = { { 1900.0, 1130.0, 0.0 }, { 2100.0, 1130.0, 0.0 }, { 1900.0, 1350.0, 0.0 }, { 1950.0, 1350.0, 0.0 }, { 1900.0, 1550.0, 0.0 }, { 2000.0, 1550.0, 0.0 }, { 1900.0, 1750.0, 0.0 }, { 2400.0, 1750.0, 0.0 } }; static GLdouble innerquadstrip[8][3] = { { 2000.0, 1230.0, 0.0 }, { 2050.0, 1230.0, 0.0 }, { 1920.0, 1350.0, 0.0 }, { 1940.0, 1350.0, 0.0 }, { 1920.0, 1550.0, 0.0 }, { 1980.0, 1550.0, 0.0 }, { 2000.0, 1650.0, 0.0 }, { 2400.0, 1650.0, 0.0 } }; // add one large quadstrip for (i = 0; i < 8; i++) { coords->push_back(osg::Vec3(quadstrip[i][0],quadstrip[i][2],quadstrip[i][1])); tcs->push_back(osg::Vec2(quadstrip[i][0],quadstrip[i][1])/200.0); nrms->push_back(nrm); } for (i = 0; i < 8; i++) { coords->push_back(osg::Vec3(innerquadstrip[i][0],innerquadstrip[i][2],innerquadstrip[i][1])); tcs->push_back(osg::Vec2(innerquadstrip[i][0],innerquadstrip[i][1])/200.0); nrms->push_back(nrm); } gtess->setVertexArray(coords); gtess->setNormalArray(nrms); gtess->setNormalBinding(osg::Geometry::BIND_PER_VERTEX); gtess->setTexCoordArray(0,tcs); // demonstrate that the Tessellator makes textured tessellations osg::StateSet* stateset = new osg::StateSet(); osg::Image* image = osgDB::readImageFile("Cubemap_snow/posy.jpg"); if (image) { osg::Texture2D* texture = new osg::Texture2D; texture->setImage(image); texture->setWrap(osg::Texture2D::WRAP_S, osg::Texture2D::REPEAT); texture->setWrap(osg::Texture2D::WRAP_T, osg::Texture2D::REPEAT); stateset->setTextureAttributeAndModes(0,texture,osg::StateAttribute::ON); } gtess->setStateSet( stateset ); int nstart=0; // The derived class tessellateDemoGeometry retains the original contours for re-use. gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::TRIANGLE_STRIP,nstart,8));nstart+=8; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::TRIANGLE_STRIP,nstart,8));nstart+=8; gtess->setTessellationType(osgUtil::Tessellator::TESS_TYPE_GEOMETRY); gtess->setBoundaryOnly(true); gtess->setWindingType( osgUtil::Tessellator::TESS_WINDING_ABS_GEQ_TWO); // so that first change in wind type makes the commonest tessellation - ODD. return gtess; } osg::Geometry *makeSideWall (const float xpos) { // demonstrate making a rectangular 'wall' with 2 holes in it. osg::Geometry *gtess= new osg::Geometry; int i; osg::Vec3Array *coords = new osg::Vec3Array; osg::Vec3Array *nrms = new osg::Vec3Array; osg::Vec2Array *tcs = new osg::Vec2Array; osg::Vec3 nrm(-1,0,0); // front wall static GLdouble wall[4][2] = { { 1130.0, 0.0 }, { 1130.0, 300.0 } , { 1340.0,300.0 }, { 1340.0,0.0 } }; gtess->setVertexArray(coords); gtess->setNormalArray(nrms); gtess->setNormalBinding(osg::Geometry::BIND_PER_VERTEX); gtess->setTexCoordArray(0,tcs); for (i = 0; i < 4; i++) { coords->push_back(osg::Vec3(xpos,wall[i][1],wall[i][0])); tcs->push_back(osg::Vec2(wall[i][1],wall[i][0])/100.0); nrms->push_back(nrm); } int nstart=0; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,nstart,4));nstart+=4; for (i = 0; i < 24; i++) { // make an ellipse hole float y=150+50*cos(i*2*osg::PI/24.0); float z=1300+30* sin(i*2*osg::PI/24.0); coords->push_back(osg::Vec3(xpos,y,z)); tcs->push_back(osg::Vec2(y,z)/100.0); nrms->push_back(nrm); } gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::POLYGON,nstart,24));nstart+=24; for (i = 0; i < 5; i++) { // make a pentagonal hole float y=150+50*cos(i*2*osg::PI/5.0); float z=1200+40* sin(i*2*osg::PI/5.0); coords->push_back(osg::Vec3(xpos,y,z)); tcs->push_back(osg::Vec2(y,z)/100.0); nrms->push_back(nrm); } gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::POLYGON,nstart,5));nstart+=5; // demonstrate that the Tessellator makes textured tessellations osg::StateSet* stateset = new osg::StateSet(); osg::Image* image = osgDB::readImageFile("Cubemap_snow/posx.jpg"); if (image) { osg::Texture2D* texture = new osg::Texture2D; texture->setImage(image); texture->setWrap(osg::Texture2D::WRAP_S, osg::Texture2D::REPEAT); texture->setWrap(osg::Texture2D::WRAP_T, osg::Texture2D::REPEAT); stateset->setTextureAttributeAndModes(0,texture,osg::StateAttribute::ON); } gtess->setStateSet( stateset ); osg::ref_ptr tscx=new osgUtil::Tessellator; // the v1.2 multi-contour Tessellator. // we use the geometry primitives to describe the contours which are tessellated. // Winding odd means leave hole in surface where there are 2,4,6... contours circling the point. tscx->setTessellationType(osgUtil::Tessellator::TESS_TYPE_GEOMETRY); tscx->setBoundaryOnly(false); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_ODD); // so that first change in wind type makes the commonest tessellation - ODD. tscx->retessellatePolygons(*gtess); return gtess; } osg::Geometry *makeFrontWall (const float zpos) { // an example of using one tessellation to make a 'house' wall // describe the wall as a pentagon, then door & 4 windows are further contours // tessellate the set of contours to make a 'house wall' from the Boolean-like operations. int nstart=0; // counts vertices used for the geometry primitives osg::Geometry *gtess= new osg::Geometry; int i; osg::Vec3Array *coords = new osg::Vec3Array; osg::Vec3Array *nrms = new osg::Vec3Array; osg::Vec2Array *tcs = new osg::Vec2Array; osg::Vec3 nrm(0,-1,0); // front wall static GLdouble wall[5][2] = { { 2200.0, 1130.0 }, { 2600.0, 1130.0 }, { 2600.0, 1340.0 }, { 2400.0, 1440.0 }, { 2200.0, 1340.0 } }; static GLdouble door[4][2] = { { 2360.0, 1130.0 }, { 2440.0, 1130.0 }, { 2440.0, 1230.0 }, { 2360.0, 1230.0 } }; static GLdouble windows[16][2] = { { 2240.0, 1180.0 }, { 2330.0, 1180.0 }, { 2330.0, 1220.0 }, { 2240.0, 1220.0 }, { 2460.0, 1180.0 }, { 2560.0, 1180.0 }, { 2560.0, 1220.0 }, { 2460.0, 1220.0 }, { 2240.0, 1280.0 }, { 2330.0, 1280.0 }, { 2330.0, 1320.0 }, { 2240.0, 1320.0 }, { 2460.0, 1280.0 }, { 2560.0, 1280.0 }, { 2560.0, 1320.0 }, { 2460.0, 1320.0 } }; gtess->setVertexArray(coords); gtess->setNormalArray(nrms); gtess->setNormalBinding(osg::Geometry::BIND_PER_VERTEX); gtess->setTexCoordArray(0,tcs); // add one large pentagon -the wall for (i = 0; i < 5; i++) { coords->push_back(osg::Vec3(wall[i][0],zpos,wall[i][1])); tcs->push_back(osg::Vec2(wall[i][0],wall[i][1])/100.0); nrms->push_back(nrm); } gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::POLYGON,nstart,5));nstart+=5; // add first hole, a door for (i = 0; i < 4; i++) { coords->push_back(osg::Vec3(door[i][0],zpos,door[i][1])); tcs->push_back(osg::Vec2(door[i][0],door[i][1])/100.0); nrms->push_back(nrm); } // and windows for (i = 0; i < 16; i++) { coords->push_back(osg::Vec3(windows[i][0],zpos,windows[i][1])); tcs->push_back(osg::Vec2(windows[i][0],windows[i][1])/100.0); nrms->push_back(nrm); } gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,nstart,20));nstart+=20; // demonstrate that the Tessellator makes textured tessellations osg::StateSet* stateset = new osg::StateSet(); osg::Image* image = osgDB::readImageFile("Cubemap_snow/posy.jpg"); if (image) { osg::Texture2D* texture = new osg::Texture2D; texture->setImage(image); texture->setWrap(osg::Texture2D::WRAP_S, osg::Texture2D::REPEAT); texture->setWrap(osg::Texture2D::WRAP_T, osg::Texture2D::REPEAT); stateset->setTextureAttributeAndModes(0,texture,osg::StateAttribute::ON); } gtess->setStateSet( stateset ); // We use a Tessellator to produce the tessellation required once only // and the contours are discarded. osg::ref_ptr tscx=new osgUtil::Tessellator; // the v1.2 multi-contour Tessellator. tscx->setTessellationType(osgUtil::Tessellator::TESS_TYPE_GEOMETRY); tscx->setBoundaryOnly(false); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_ODD); // so that first change in wind type makes the commonest tessellation - ODD. tscx->retessellatePolygons(*gtess); return gtess; } osg::Geode *makeHouse (void) { osg::Geode *gd = new osg::Geode; gd->addDrawable(makeFrontWall(0.0)); gd->addDrawable(makeFrontWall(300.0)); gd->addDrawable(makeSideWall(2200.0)); gd->addDrawable(makeSideWall(2600.0)); return gd; } osg::Geometry *makePols (void) { tessellateDemoGeometry *gtess= new tessellateDemoGeometry; int i; osg::Vec3Array *coords = new osg::Vec3Array; osg::Vec3Array *nrms = new osg::Vec3Array; osg::Vec2Array *tcs = new osg::Vec2Array; osg::Vec3 nrm(0,-1,0); // coordinates from red book code but shifted by 1000 & 2000 for alternate Tessellatory things. static GLdouble rects[12][3] = { { 50.0, 50.0, 0.0 }, { 300.0, 50.0, 0.0 }, { 300.0, 300.0, 0.0 }, { 50.0, 300.0, 0.0 }, { 100.0, 100.0, 0.0 }, { 250.0, 100.0, 0.0 }, { 250.0, 250.0, 0.0 }, { 100.0, 250.0, 0.0 }, { 150.0, 150.0, 0.0 }, { 200.0, 150.0, 0.0 }, { 200.0, 200.0, 0.0 }, { 150.0, 200.0, 0.0 } }; static GLdouble rectsMidanti[12][3] = // the centre 2 contours are traversed opposite order to outer contour. { { 1050.0, 50.0, 0.0 }, { 1300.0, 50.0, 0.0 }, { 1300.0, 300.0, 0.0 }, { 1050.0, 300.0, 0.0 }, { 1250.0, 100.0, 0.0 }, { 1100.0, 100.0, 0.0 }, { 1100.0, 250.0, 0.0 }, { 1250.0, 250.0, 0.0 }, { 1200.0, 150.0, 0.0 }, { 1150.0, 150.0, 0.0 }, { 1150.0, 200.0, 0.0 }, { 1200.0, 200.0, 0.0 } }; static GLdouble spiral[16][3] = // shift by 1000; nb the order of vertices is reversed from that of the red book { { 3400.0, 250.0, 0.0 }, { 3400.0, 50.0, 0.0 }, { 3050.0, 50.0, 0.0 }, { 3050.0, 400.0, 0.0 }, { 3350.0, 400.0, 0.0 }, { 3350.0, 100.0, 0.0 }, { 3100.0, 100.0, 0.0 }, { 3100.0, 350.0, 0.0 }, { 3300.0, 350.0, 0.0 }, { 3300.0, 150.0, 0.0 }, { 3150.0, 150.0, 0.0 }, { 3150.0, 300.0, 0.0 }, { 3250.0, 300.0, 0.0 }, { 3250.0, 200.0, 0.0 }, { 3200.0, 200.0, 0.0 }, { 3200.0, 250.0, 0.0 } }; static GLdouble quad1[4][3] = // shift by 2000 for next 3 things { { 2050.0, 150.0, 0.0 }, { 2350.0, 150.0, 0.0 }, { 2350.0, 200.0, 0.0 }, { 2050.0, 200.0, 0.0 } }; static GLdouble quad2[4][3] = { { 2100.0, 100.0, 0.0 }, { 2300.0, 100.0, 0.0 }, { 2300.0, 350.0, 0.0 }, { 2100.0, 350.0, 0.0 } }; static GLdouble tri[3][3] = { { 2200.0, 50.0, 0.0 }, { 2250.0, 300.0, 0.0 }, { 2150.0, 300.0, 0.0 } }; static GLdouble quad3[4][3] = { { 100.0, 1100.0, 0.0 }, { 1300.0, 1100.0, 0.0 }, { 1300.0, 2350.0, 0.0 }, { 100.0, 2350.0, 0.0} }; static GLdouble quadstrip[8][3] = { { 900.0, 1130.0, 0.0 }, { 1100.0, 1130.0, 0.0 }, { 900.0, 1350.0, 0.0 }, { 950.0, 1350.0, 0.0 }, { 900.0, 1550.0, 0.0 }, { 1000.0, 1550.0, 0.0 }, { 900.0, 1750.0, 0.0 }, { 1400.0, 1750.0, 0.0 } }; for (i = 0; i < 12; i++) { coords->push_back(osg::Vec3(rects[i][0],rects[i][2],rects[i][1])); tcs->push_back(osg::Vec2(rects[i][0],rects[i][1])/200.0); nrms->push_back(nrm); } for (i = 0; i < 12; i++) { coords->push_back(osg::Vec3(rectsMidanti[i][0],rectsMidanti[i][2],rectsMidanti[i][1])); tcs->push_back(osg::Vec2(rectsMidanti[i][0],rectsMidanti[i][1])/200.0); nrms->push_back(nrm); } for (i = 0; i < 16; i++) { // and reverse spiral to make same as that of red book ch 11 coords->push_back(osg::Vec3(spiral[15-i][0],spiral[15-i][2],spiral[15-i][1])); tcs->push_back(osg::Vec2(spiral[15-i][0],spiral[15-i][1])/200.0); nrms->push_back(nrm); } for (i = 0; i < 4; i++) { coords->push_back(osg::Vec3(quad1[i][0],quad1[i][2],quad1[i][1])); tcs->push_back(osg::Vec2(quad1[i][0],quad1[i][1])/200.0); nrms->push_back(nrm); } for (i = 0; i < 4; i++) { coords->push_back(osg::Vec3(quad2[i][0],quad2[i][2],quad2[i][1])); tcs->push_back(osg::Vec2(quad2[i][0],quad2[i][1])/200.0); nrms->push_back(nrm); } for (i = 0; i < 3; i++) { coords->push_back(osg::Vec3(tri[i][0],tri[i][2],tri[i][1])); tcs->push_back(osg::Vec2(tri[i][0],tri[i][1])/200.0); nrms->push_back(nrm); } // add one large quad with multiple holes for (i = 0; i < 4; i++) { coords->push_back(osg::Vec3(quad3[i][0],quad3[i][2],quad3[i][1])); tcs->push_back(osg::Vec2(quad3[i][0],quad3[i][1])/200.0); nrms->push_back(nrm); } { osg::Vec3 centre(300,0,1500); for (i = 0; i < 18; i++) { osg::Vec3 rim=centre+osg::Vec3(-cos(osg::DegreesToRadians((float)i*20.0)),0.0,sin(osg::DegreesToRadians((float)i*20.0)))*150.0; coords->push_back(rim); tcs->push_back(osg::Vec2(rim.x(),rim.z())/200.0); nrms->push_back(nrm); } } { osg::Vec3 centre(400,0,1800); for (i = 0; i < 18; i++) { osg::Vec3 rim=centre+osg::Vec3(-cos(osg::DegreesToRadians((float)i*15.0)),0.0,sin(osg::DegreesToRadians((float)i*15.0)))*250.0; coords->push_back(rim); tcs->push_back(osg::Vec2(rim.x(),rim.z())/200.0); nrms->push_back(nrm); } } { osg::Vec3 centre(600,0,1400); for (i = 0; i < 18; i++) { osg::Vec3 rim=centre+osg::Vec3(-cos(osg::DegreesToRadians((float)i*12.0)),0.0,sin(osg::DegreesToRadians((float)i*12.0)))*250.0; coords->push_back(rim); tcs->push_back(osg::Vec2(rim.x(),rim.z())/200.0); nrms->push_back(nrm); } } // add one large quadstrip for (i = 0; i < 8; i++) { coords->push_back(osg::Vec3(quadstrip[i][0],quadstrip[i][2],quadstrip[i][1])); tcs->push_back(osg::Vec2(quadstrip[i][0],quadstrip[i][1])/200.0); nrms->push_back(nrm); } gtess->setVertexArray(coords); gtess->setNormalArray(nrms); gtess->setNormalBinding(osg::Geometry::BIND_PER_VERTEX); gtess->setTexCoordArray(0,tcs); // demonstrate that the Tessellator makes textured tessellations osg::StateSet* stateset = new osg::StateSet(); osg::Image* image = osgDB::readImageFile("Cubemap_snow/posz.jpg"); if (image) { osg::Texture2D* texture = new osg::Texture2D; texture->setImage(image); texture->setWrap(osg::Texture2D::WRAP_S, osg::Texture2D::REPEAT); texture->setWrap(osg::Texture2D::WRAP_T, osg::Texture2D::REPEAT); stateset->setTextureAttributeAndModes(0,texture,osg::StateAttribute::ON); } gtess->setStateSet( stateset ); int nstart=0; // the contours accepoted are polygons; quads & tris. Trifans can bve added later. gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,nstart,12));nstart+=12; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,nstart,12));nstart+=12; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::POLYGON,nstart,16));nstart+=16; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,nstart,4));nstart+=4; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::QUADS,nstart,4));nstart+=4; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::TRIANGLES,nstart,3));nstart+=3; // A rectabngle with multiple holes gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::LINE_LOOP,nstart,4));nstart+=4; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::TRIANGLE_FAN,nstart,18));nstart+=18; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::POLYGON,nstart,18));nstart+=18; gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::POLYGON,nstart,18));nstart+=18; // test for quad strip gtess->addPrimitiveSet(new osg::DrawArrays(osg::PrimitiveSet::TRIANGLE_STRIP,nstart,8));nstart+=8; // We need to access the tessellatable contours again to demonstrate all types of tessellation. // I could add the Tessellator to the geometry as userdata, but here // I use the derived tessellateDemoGeometry to hold both the drawable geode and the original contours. gtess->setTessellationType(osgUtil::Tessellator::TESS_TYPE_GEOMETRY); gtess->setBoundaryOnly(true); gtess->setWindingType( osgUtil::Tessellator::TESS_WINDING_ABS_GEQ_TWO); // so that first change in wind type makes the commonest tessellation - ODD. return gtess; } osg::Node* createHUD() { // add a string reporting the type of winding rule tessellation applied osg::Geode* geode = new osg::Geode(); std::string timesFont("fonts/arial.ttf"); // turn lighting off for the text and disable depth test to ensure its always ontop. osg::StateSet* stateset = geode->getOrCreateStateSet(); stateset->setMode(GL_LIGHTING,osg::StateAttribute::OFF); // Disable depth test, and make sure that the hud is drawn after everything // else so that it always appears ontop. stateset->setMode(GL_DEPTH_TEST,osg::StateAttribute::OFF); stateset->setRenderBinDetails(11,"RenderBin"); osg::Vec3 position(150.0f,900.0f,0.0f); osg::Vec3 delta(0.0f,-30.0f,0.0f); { osgText::Text* text = new osgText::Text; geode->addDrawable( text ); text->setFont(timesFont); text->setPosition(position); text->setText("Tessellation example - no tessellation (use 'W' wireframe to visualise)"); text->setColor(osg::Vec4(1.0,1.0,0.8,1.0)); position += delta; } { osgText::Text* text = new osgText::Text; geode->addDrawable( text ); text->setFont(timesFont); text->setPosition(position); text->setText("Press 'n' to use an alternative tessellation."); } // create the hud. osg::MatrixTransform* modelview_abs = new osg::MatrixTransform; modelview_abs->setReferenceFrame(osg::Transform::ABSOLUTE_RF); modelview_abs->setMatrix(osg::Matrix::identity()); modelview_abs->addChild(geode); osg::Projection* projection = new osg::Projection; projection->setMatrix(osg::Matrix::ortho2D(0,1280,0,1024)); projection->addChild(modelview_abs); return projection; } osg::Group *makeTessellateExample (void) { osg::Group *grp=new osg::Group; osg::Geode *gd=new osg::Geode; gd->addDrawable(makePols()); gd->addDrawable(makePolsTwo()); grp->addChild(gd); grp->addChild(makeHouse()); return grp; } class setTessellateVisitor : public osg::NodeVisitor { // searches a loaded model tree for tessellatable geometries. // used with any database model which has a renderGroup (Geode) named 'tessellate' // or you can force a type of tess with special names or a sub-class of Geode could have extra information // of course you can use any name to detect what is to be tessellated! // all the polygons within the specific node are deemed to be contours, so // any tessellation can be requested. public: setTessellateVisitor():osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ALL_CHILDREN) { } virtual void apply(osg::Geode& geode) { if (geode.getName().compare(0,9,"tessellate")==0) { for(unsigned int i=0;i(geode.getDrawable(i)); if (geom) { osg::ref_ptr tscx=new osgUtil::Tessellator(); if (tscx.valid()) { tscx->setTessellationType(osgUtil::Tessellator::TESS_TYPE_GEOMETRY); if (geode.getName()== "tessellate") { // add a Tessellator so that this geom is retessellated when N is pressed tscx->setBoundaryOnly(true); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_ABS_GEQ_TWO); // so that first change in wind type makes the commonest tessellation - ODD. geom->setUserData(tscx.get()); } else if (geode.getName()== "tessellate odd") { // OR you can just apply the Tessellator once only, using these different types tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_ODD); // commonest tessellation - ODD. tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate odd bound") { tscx->setBoundaryOnly(true); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_ODD); // tessellation - ODD, only show boundary. tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate positive") { tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_POSITIVE); // tessellation - pos. tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate positive bound") { tscx->setBoundaryOnly(true); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_POSITIVE); tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate negative") { tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_NEGATIVE); tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate negative bound") { tscx->setBoundaryOnly(true); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_NEGATIVE); tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate nonzero") { tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_NONZERO); tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate nonzero bound") { tscx->setBoundaryOnly(true); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_NONZERO); tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate geq2") { tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_ABS_GEQ_TWO); tscx->retessellatePolygons(*geom); } else if (geode.getName()== "tessellate geq2 bound") { tscx->setBoundaryOnly(true); tscx->setWindingType( osgUtil::Tessellator::TESS_WINDING_ABS_GEQ_TWO); tscx->retessellatePolygons(*geom); } } } } } } }; class cxTessellateVisitor : public osg::NodeVisitor { // special to this demo, traverses SG and finds nodes which have been tessellated // for test/demo purposes these nodes are of type tessellateDemoGeometry // but you could store the Tessellator as UserData or however you like. // the Tessellator holds copies of the original contours used in the tessellation // In this visitor, I reuse the contours to make a different type of tessellation. public: cxTessellateVisitor():osg::NodeVisitor(osg::NodeVisitor::TRAVERSE_ALL_CHILDREN) { } virtual void apply(osg::Geode& geode) { for(unsigned int i=0;i(geode.getDrawable(i)); if (geom) { if (!geom->getBoundaryOnly()) { // turn on bounds only // NB this shows only the true boundary of the curves, no internal edges geom->setBoundaryOnly(true); } else { // change to next type of tessellation... geom->setBoundaryOnly(false); switch (geom->getWindingType()) { case osgUtil::Tessellator::TESS_WINDING_ODD: geom->setWindingType(osgUtil::Tessellator::TESS_WINDING_NONZERO); break; case osgUtil::Tessellator::TESS_WINDING_NONZERO: geom->setWindingType( osgUtil::Tessellator::TESS_WINDING_POSITIVE); break; case osgUtil::Tessellator::TESS_WINDING_POSITIVE: geom->setWindingType( osgUtil::Tessellator::TESS_WINDING_NEGATIVE); break; case osgUtil::Tessellator::TESS_WINDING_NEGATIVE: geom->setWindingType( osgUtil::Tessellator::TESS_WINDING_ABS_GEQ_TWO); break; case osgUtil::Tessellator::TESS_WINDING_ABS_GEQ_TWO: geom->setWindingType( osgUtil::Tessellator::TESS_WINDING_ODD); break; } } switch (geom->getWindingType()) { // a text to be added to the scene. case osgUtil::Tessellator::TESS_WINDING_ODD: str="TESS_WINDING_ODD"; break; case osgUtil::Tessellator::TESS_WINDING_NONZERO: str="TESS_WINDING_NONZERO"; break; case osgUtil::Tessellator::TESS_WINDING_POSITIVE: str="TESS_WINDING_POSITIVE"; break; case osgUtil::Tessellator::TESS_WINDING_NEGATIVE: str="TESS_WINDING_NEGATIVE"; break; case osgUtil::Tessellator::TESS_WINDING_ABS_GEQ_TWO: str="TESS_WINDING_ABS_GEQ_TWO"; break; } if (geom->getBoundaryOnly()) str += " Boundary"; geom->retessellatePolygons(*geom); } osgText::Text* txt = dynamic_cast(geode.getDrawable(i)); if (txt) { const osg::Vec4& ct=txt->getColor(); // pick the text to be changed by its color if (ct.z()<0.9) { txt->setText(str.c_str()); } } } traverse(geode); } std::string str; // a label for on screen display }; class KeyboardEventHandler : public osgGA::GUIEventHandler { // extra event handler traps 'n' key to re-tessellate any tessellated geodes. public: KeyboardEventHandler(osg::Node *nd): _scene(nd) {} virtual bool handle(const osgGA::GUIEventAdapter& ea,osgGA::GUIActionAdapter&) { switch(ea.getEventType()) { case(osgGA::GUIEventAdapter::KEYDOWN): { if (_scene && ea.getKey()=='n') { // re-tessellate the scene graph. // the same contours are re-tessellated using a new method. Old contours // & tessellation type are held internally in the derived Geode class tessellateDemoGeometry. cxTessellateVisitor tsv; _scene->accept(tsv); return true; } break; } default: break; } return false; } osg::Node *_scene; }; int main( int argc, char **argv ) { // use an ArgumentParser object to manage the program arguments. osg::ArgumentParser arguments(&argc,argv); // construct the viewer. osgViewer::Viewer viewer; // read the scene from the list of file specified commandline args. osg::ref_ptr loadedModel = osgDB::readNodeFiles(arguments); // if no model has been successfully loaded report failure. if (!loadedModel) { loadedModel=makeTessellateExample(); } else { // if there is a loaded model: // tessellate by searching for geode called tessellate & tessellate it setTessellateVisitor tsv; loadedModel->accept(tsv); } // create the hud. osg::Group *gload= dynamic_cast (loadedModel.get()); gload->addChild(createHUD()); osgUtil::Optimizer optimizer; optimizer.optimize(loadedModel.get() ); // set the scene to render viewer.setSceneData(loadedModel.get()); // add event handler for keyboard 'n' to retessellate viewer.addEventHandler(new KeyboardEventHandler(loadedModel.get())); return viewer.run(); }