Test and Example Programs for pcl_simulation
mfallon and hordurj march 2012

1. sim_viewer.cpp
purpose: simulate in viewer which is almost the same as pcl_viewer
status : use the mouse to drive around, and 'v' to capture a cloud. reads vtk and obj. 
         visualizes vtk and makes pcd of obj. conflict between RL and VTK means doesn't visualize/simulate properly
was    : range_pcd_viewer.cpp

2. sim_terminal_demo.cpp
purpose: simple app to demo speed and api to pcl_simulation
status : reads obj, make a series of 640x480 simulated point clouds and exits
depndcy: OpenCV for writing png images

3. sim_test_performance.cpp
purpose: GLUT/GLEW viewer used by Hordur to test GLSL optimizations. Creates two different viewing planes
status : reads obj, creates window, use keyboard to drive around environment
was    : range_performance_test.cpp

4. sim_test_simple
purpose: similar code to #3 but has a 2x2 grid each containing 640x480 windows, but operates as #1. press 'v' to capture a cloud to file (only works properly if 2x2 changed to 1x1)
status : reads obj, creates window, use keyboard to drive around environment
was    : range_test_v2.cpp
