Function renderGoldfeather

OpenCSG/src/renderGoldfeather.cpp:419–486

    } // unnamed namespace

    static void renderGoldfeather(const std::vector<Primitive*>& primitives)
    {
        scissor = new ScissorMemo;

        Batcher batches(primitives);

        scissor->setIntersected(primitives);

        for (std::vector<Batch>::const_iterator itr = batches.begin(); itr != batches.end(); ++itr) {
            unsigned int maxConvexity = Algo::getConvexity(*itr);
            for (unsigned int currentLayer = 0; currentLayer < maxConvexity; ++currentLayer) {
                
                if (channelMgr->request() == NoChannel) {
                    channelMgr->free();
                    channelMgr->request();
                }

                channelMgr->renderToChannel(true); glColor4ub(255, 255, 255, 255);
                glStencilMask(OpenGL::stencilMask);
                glEnable(GL_STENCIL_TEST);

                glDepthFunc(GL_ALWAYS);
                glDepthMask(GL_TRUE);

                scissor->setCurrent(*itr);
                scissor->store(channelMgr->current());
                scissor->enableScissor();

                if (maxConvexity == 1) {
                    // shapes of interest: we need to determine which parts of them are visible.
                    // first assume they are fully visible
                    glStencilFunc(GL_ALWAYS, 0, OpenGL::stencilMask);
                    glStencilOp(GL_REPLACE, GL_REPLACE, GL_REPLACE);
                    glEnable(GL_CULL_FACE);

                    for (Batch::const_iterator j = itr->begin(); j != itr->end(); ++j) {
                        glCullFace((*j)->getOperation() == Intersection ? GL_BACK : GL_FRONT);
                        (*j)->render();
                    }

                    glDisable(GL_CULL_FACE);
                } else {
                    // shapes of interest: we need to determine the appropriate layer of 
                    // the shapes, using stencil counting
                    glClear(GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
                    OpenGL::renderLayer(currentLayer, *itr);
                    glClear(GL_STENCIL_BUFFER_BIT);
                }

                GLenum depthFunc = getParityDepthFunc();
                if (depthFunc == GL_GREATER)
                    scissor->enableDepthBoundsFront();
                else if (depthFunc == GL_LEQUAL)
                    scissor->enableDepthBoundsBack();

                parityTestAndDiscard(*itr, primitives, false, OpenGL::stencilMask);

                scissor->disableDepthBounds();