/**
* clip this view so that outside of the visible bounds can be hidden.
*/
void ScrollView::onBeforeDraw()
{
if (_clippingToBounds)
{
_scissorRestored = false;
Rect frame = getViewRect();
auto glview = Director::getInstance()->getOpenGLView();
if (glview->isScissorEnabled()) {
_scissorRestored = true;
_parentScissorRect = glview->getScissorRect();
//set the intersection of _parentScissorRect and frame as the new scissor rect
if (frame.intersectsRect(_parentScissorRect)) {
float x = MAX(frame.origin.x, _parentScissorRect.origin.x);
float y = MAX(frame.origin.y, _parentScissorRect.origin.y);
float xx = MIN(frame.origin.x+frame.size.width, _parentScissorRect.origin.x+_parentScissorRect.size.width);
float yy = MIN(frame.origin.y+frame.size.height, _parentScissorRect.origin.y+_parentScissorRect.size.height);
glview->setScissorInPoints(x, y, xx-x, yy-y);
}
}
else {
glEnable(GL_SCISSOR_TEST);
glview->setScissorInPoints(frame.origin.x, frame.origin.y, frame.size.width, frame.size.height);
}
}
}
void Layout::onBeforeVisitScissor()
{
auto glview = Director::DirectorInstance->getOpenGLView();
// apply scissor test
_scissorOldState = glview->isScissorEnabled();
if (false == _scissorOldState)
{
glEnable(GL_SCISSOR_TEST);
}
// apply scissor box
Rect clippingRect = getClippingRect();
_clippingOldRect = glview->getScissorRect();
if (false == _clippingOldRect.equals(clippingRect))
{
glview->setScissorInPoints(clippingRect.origin.x,
clippingRect.origin.y,
clippingRect.size.width,
clippingRect.size.height);
}
}