qgis/Quantum-GIS — pull request #194 by dakcarto (2012-07-18 22:14:34+00:00)
Title: sip binding for QgsLabelingEngineInterface::labelsWithinRect()

canvas = qgis.utils.iface.mapCanvas()
ext = canvas.extent()
labels = canvas.mapRenderer().labelingEngine().labelsWithinRect(ext)

returns labels shown within the canvas (QList of QgsLabelPosition)