模型自身面片重合引起的闪烁破损解决方法

当面片重合的时候，会出现Z-Fighting闪烁现象，可以通过glPolygonOffset来解决

但是一个几何体Geode自身部分面片重合，例如飞机盘旋飞行对应的高度面，就需要使用GL_SAMPLE_ALPHA_TO_COVERAGE_ARB替换GL_BLEND

//geom->getOrCreateStateSet()->setMode(GL_BLEND,osg::StateAttribute::ON | osg::StateAttribute::PROTECTED | osg::StateAttribute::OVERRIDE);
geom->getOrCreateStateSet()->setMode(GL_SAMPLE_ALPHA_TO_COVERAGE_ARB, osg::StateAttribute::ON | osg::StateAttribute::PROTECTED | osg::StateAttribute::OVERRIDE);

有时候可能需要设置

osg::DisplaySettings::instance()->setNumMultiSamples(4);//多重采样设置反走样

或者

osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits();
traits->samples = 4;//多重采样设置反走样
traits->windowDecoration = false;
traits->x = nX;
traits->y = nY;
traits->width = nW;
traits->height = nH;
traits->doubleBuffer = true;
traits->inheritedWindowData = pInheritedWindowData;