pybullet, more robust multi-server connections

Windows shared memory: allow to use custom key.
Improve GUI performance on Windows, submit letters in text as a batch (fewer draw-calls)
quadruped.py: first try to connect to SHARED_MEMORY, if it fails (<0) use GUI
increase Chrome about://tracing json export capacity (press 'p' in Example Browser)
UDP physics server: add --port and --sharedMemoryKey command-line arguments
PhysicsServerExample: add --sharedMemoryKey command-line option (for VR example too)
ExampleBrowser: sleep a few milliseconds if rendering is too fast, use --minUpdateTimeMicroSecs=0 to disable

examples/pybullet/quadruped.py

@@ -2,11 +2,15 @@ import pybullet as p
 import time
 import math
 
-p.connect(p.SHARED_MEMORY)
+
+physId = p.connect(p.SHARED_MEMORY)
+if (physId<0):
+	p.connect(p.GUI)
+
 p.loadURDF("plane.urdf")
 p.setGravity(0,0,-1)
 p.setRealTimeSimulation(0)
-quadruped = p.loadURDF("quadruped/quadruped.urdf",10,-2,2)
+quadruped = p.loadURDF("quadruped/quadruped.urdf",1,-2,2)
 #p.getNumJoints(1)
 #right front leg
 p.resetJointState(quadruped,0,1.57)
@@ -82,6 +86,7 @@ jump_amp = 0.5
 #jump
 t_end = time.time() + 10
 i=0
+t=0
 while time.time() < t_end:
 	t = time.time()
 	p.setJointMotorControl(quadruped,0,p.POSITION_CONTROL,math.sin(t*speed)*jump_amp+1.57,p_gain)