Initial checkin of FrameViewer classes

FrameViewer.py

@@ -0,0 +1,159 @@
+#!/usr/bin/python
+import sys, os, math
+from PyQt4.QtCore import *
+from PyQt4.QtGui  import *
+
+class GraphicsView(QGraphicsView):
+    # Signals
+    scaleChanged = pyqtSignal(float)
+    focusIn      = pyqtSignal()
+
+    def __init__(self, parent=None):
+        QGraphicsView.__init__(self, parent)
+        self.setRenderHint(QPainter.Antialiasing)
+        self.setRenderHint(QPainter.TextAntialiasing)
+        self.setFrameStyle(QFrame.NoFrame)
+
+        self.current_scale_ = 1
+        self.active_ = False
+
+    def isActive(self):
+        return self.active_
+
+    def activate(self):
+        if not self.active_:
+            self.active_ = True
+            self.setFocus(Qt.OtherFocusReason)
+            self.setFrameStyle(QFrame.Panel)
+            self.update()
+
+    def deactivate(self):
+        if self.active_:
+            self.active_ = False
+            self.clearFocus()
+            self.setFrameStyle(QFrame.NoFrame)
+            self.update()
+
+    def setScaleRelative(self, factor):
+        QGraphicsView.scale(self, factor, factor)
+        self.current_scale_ *= factor
+        self.scaleChanged.emit(self.current_scale_)
+        # TODO: Stop at minimum scale
+
+    def setScaleAbsolute(self, scale):
+        m = QMatrix()
+        m.scale(scale, scale)
+        self.current_scale_ = scale
+        self.setMatrix(m)
+        self.scaleChanged.emit(self.current_scale_)
+        # TODO: Stop at minimum scale
+
+    def getScale(self):
+        return self.current_scale_
+
+    def wheelEvent(self, event):
+        factor = 1.41 ** (event.delta() / 240.0)
+        self.setScaleRelative(factor)
+
+    def focusInEvent(self, event):
+        self.focusIn.emit()
+
+    # TODO: Make window panable by CTRL-Mouse-Drag or similar
+
+class FrameViewer(QWidget):
+    # Signals
+    activeSceneViewChanged = pyqtSignal(GraphicsView)
+
+    def __init__(self, parent=None):
+        QMainWindow.__init__(self, parent)
+
+    def getActiveSceneView(self):
+        pass
+
+    def activateNextSceneView(self):
+        pass
+
+    def activatePreviousSceneView(self):
+        pass
+
+    def setActiveScaleAbsolute(self, scale):
+        self.getActiveSceneView().setScaleAbsolute(scale)
+
+    def setActiveScaleRelative(self, scale):
+        self.getActiveSceneView().setScaleRelative(scale)
+
+class SingleFrameViewer(FrameViewer):
+    def __init__(self, annotation_scene, parent=None):
+        FrameViewer.__init__(self, parent)
+        self.scene = annotation_scene
+        self.scene_view = GraphicsView()
+        self.scene_view.setScene(self.scene)
+        self.scene_view.activate()
+        self.layout = QHBoxLayout(self)
+        self.layout.addWidget(self.scene_view)
+        self.setLayout(self.layout)
+
+    def getActiveSceneView(self):
+        return self.scene_view
+
+class MultiFrameEqualViewer(FrameViewer):
+    def __init__(self, annotation_scenes, parent=None):
+        assert(len(annotation_scenes) > 0)
+        FrameViewer.__init__(self, parent)
+        self.active_scene_view = -1
+        self.scenes = annotation_scenes
+        self.scene_views = []
+        for scene in self.scenes:
+            scene_view = GraphicsView()
+            scene_view.setScene(scene)
+            scene_view.focusIn.connect(self.activateFocusedSceneView)
+            self.scene_views.append(scene_view)
+        n_rows = math.ceil(math.sqrt(len(self.scene_views)))
+        n_cols = math.ceil(len(self.scenes) / n_rows)
+        self.layout = QGridLayout(self)
+        for i, scene_view in enumerate(self.scene_views):
+            self.layout.addWidget(scene_view, i/n_cols, i%n_cols)
+        self.setLayout(self.layout)
+        self.activateSceneView(0)
+
+    def activateSceneView(self, index):
+        if index != self.active_scene_view:
+            for scene_view in self.scene_views:
+                scene_view.deactivate()
+            self.active_scene_view = index
+            self.scene_views[index].activate()
+            self.activeSceneViewChanged.emit(self.getActiveSceneView())
+
+    def activateFocusedSceneView(self):
+        sender = self.sender()
+        for index, scene_view in enumerate(self.scene_views):
+            if scene_view == sender:
+                self.activateSceneView(index)
+
+    def getActiveSceneView(self):
+        return self.scene_views[self.active_scene_view]
+
+def get_dummy_scene(filename):
+    scene = QGraphicsScene()
+    scene.addPixmap(QPixmap(filename))
+    return scene
+
+def main():
+    app = QApplication(sys.argv)
+
+    scenes = []
+    for i in range(4):
+        scenes.append(get_dummy_scene("/home/mfischer/data/test.jpg"))
+
+    #viewer = SingleFrameViewer(scene)
+    viewer = MultiFrameEqualViewer(scenes)
+    viewer.show()
+
+    return app.exec_()
+
+if __name__ == '__main__':
+    sys.exit(main())
+
+# Necessary information
+# - Functionalities
+#   - Display zoom level