Remove examples which use the old opengl_cb API

I made an attempt to convert some of them, but in the end, meh, I can't
be bothered. Do it yourself if you care, PRs to restore any of these
example by using the render API might be accepted.

The qt_opengl example was converted before; just fixing some old
comments in it.

Fixes: #38

1 files changed, 2 insertions, 2 deletions

diff --git a/libmpv/qt_opengl/mpvwidget.cpp b/libmpv/qt_opengl/mpvwidget.cpp
index 16ee17e..c32a443 100644
--- a/libmpv/qt_opengl/mpvwidget.cpp
+++ b/libmpv/qt_opengl/mpvwidget.cpp
@@ -123,11 +123,11 @@ void MpvWidget::handle_mpv_event(mpv_event *event)
     }
 }
 
-// Make Qt invoke mpv_opengl_cb_draw() to draw a new/updated video frame.
+// Make Qt invoke mpv_render_context_render() to draw a new/updated video frame.
 void MpvWidget::maybeUpdate()
 {
     // If the Qt window is not visible, Qt's update() will just skip rendering.
-    // This confuses mpv's opengl-cb API, and may lead to small occasional
+    // This confuses mpv's render API, and may lead to small occasional
     // freezes due to video rendering timing out.
     // Handle this by manually redrawing.
     // Note: Qt doesn't seem to provide a way to query whether update() will