Adding some documentation on the change

This commit is contained in:
Brad Davis 2015-03-17 13:49:06 -07:00
parent 71e59cfa88
commit c88f6f8f07

View file

@ -3112,6 +3112,22 @@ void Application::renderRearViewMirror(const QRect& region, bool billboard) {
_myAvatar->getOrientation() * glm::vec3(0.0f, 0.0f, -1.0f) * MIRROR_REARVIEW_BODY_DISTANCE * _myAvatar->getScale());
} else { // HEAD zoom level
// FIXME note that the positioing of the camera relative to the avatar can suffer limited
// precision as the user's position moves further away from the origin. Thus at
// /1e7,1e7,1e7 (well outside the buildable volume) the mirror camera veers and sways
// wildly as you rotate your avatar because the floating point values are becoming
// larger, squeezing out the available digits of precision you have available at the
// human scale for camera positioning.
// Previously there was a hack to correct this using the mechanism of repositioning
// the avatar at the origin of the world for the purposes of rendering the mirror,
// but it resulted in failing to render the avatar's head model in the mirror view
// when in first person mode. Presumably this was because of some missed culling logic
// that was not accounted for in the hack.
// This was removed in commit 71e59cfa88c6563749594e25494102fe01db38e9 but could be further
// investigated in order to adapt the technique while fixing the head rendering issue,
// but the complexity of the hack suggests that a better approach
_mirrorCamera.setFieldOfView(MIRROR_FIELD_OF_VIEW); // degrees
_mirrorCamera.setPosition(_myAvatar->getHead()->getEyePosition() +
_myAvatar->getOrientation() * glm::vec3(0.0f, 0.0f, -1.0f) * MIRROR_REARVIEW_DISTANCE * _myAvatar->getScale());