!U view control updated to more better way

Author: pavlog

printrun/gl/panel.py

@@ -41,12 +41,13 @@
     GL_SRC_ALPHA, glTranslatef, gluPerspective, gluUnProject, \
     glViewport, GL_VIEWPORT
 from pyglet import gl
-from .trackball import trackball, mulquat
+from .trackball import trackball, mulquat,axis_to_quat
 from .libtatlin.actors import vec
 
 class wxGLPanel(wx.Panel):
     '''A simple class for using OpenGL with wxPython.'''
 
+    orbit_control = True
     orthographic = True
     color_background = (0.98, 0.98, 0.78, 1)
     do_lights = True
@@ -80,6 +81,9 @@ def __init__(self, parent, id, pos = wx.DefaultPosition,
         self.rot_lock = Lock()
         self.basequat = [0, 0, 0, 1]
         self.zoom_factor = 1.0
+        # top view
+        self.angle_z = 0
+        self.angle_x = 0 #math.radians(90);
 
         self.gl_broken = False
 
@@ -324,6 +328,18 @@ def zoom_to_center(self, factor):
         x, y, _ = self.mouse_to_3d(self.width / 2, self.height / 2)
         self.zoom(factor, (x, y))
 
+    def orbit(self, p1x, p1y, p2x, p2y):
+
+        rz = p2x-p1x;
+        self.angle_z-=rz
+        rotz = axis_to_quat([0.0,0.0,1.0],self.angle_z)
+
+        rx = p2y-p1y;
+        self.angle_x+=rx
+        rota = axis_to_quat([1.0,0.0,0.0],self.angle_x)
+    
+        return mulquat(rotz,rota)
+
     def handle_rotation(self, event):
         if self.initpos is None:
             self.initpos = event.GetPositionTuple()
@@ -335,9 +351,13 @@ def handle_rotation(self, event):
             p1y = 1 - float(p1[1]) / (sz[1] / 2)
             p2x = float(p2[0]) / (sz[0] / 2) - 1
             p2y = 1 - float(p2[1]) / (sz[1] / 2)
-            quat = trackball(p1x, p1y, p2x, p2y, self.dist / 250.0)
-            with self.rot_lock:
-                self.basequat = mulquat(self.basequat, quat)
+            if self.orbit_control:
+                with self.rot_lock:
+                    self.basequat = self.orbit(p1x, p1y, p2x, p2y)
+            else:
+                quat = trackball(p1x, p1y, p2x, p2y, self.dist / 250.0)
+                with self.rot_lock:
+                    self.basequat = mulquat(self.basequat, quat)
             self.initpos = p2
 
     def handle_translation(self, event):