-Changes for 0.00.19 (5-14-2006) The simulation is now titled 'Energy Skate Park' The skater's potential energy is now zero when he's on the ground (by default). The skater cannot be dragged outside the window, or below ground. -Changes for 1-2-2006, 0.17 “Play” has been changed to “Go” for clarity. Add a movable “zero-point potential energy” graphic Add a clear button to e vs t graph in skater. Remove "minimize" button from e vs t in skater. Background is on by default Improved backgrounds a bit (tone down, position properly) -Changes for 12-23-2005, 0.15 Paused shows up in the play area when skater is paused. Renamed “Live” to “Play” Radio buttons match slider values. (all off when no exact location). Energy vs. Time chart comes up recording. Added color code legend for pie chart. Energy vs Position graph has a color-coded legend. Energy vs Position graph doesn't fade during pause. Renamed “Coefficient of Restitution” to “bounciness” Reset starts module running (not paused) Reset button changes the values in “edit skater” Save graphs (e.g. to compare friction on to friction off). -Changes for 11-17-2005, 0.13 Fix playback panel button sizes for 1024x768. Move Energy vs position button near other plot buttons. Rename 'show plot' to Plot Energy vs Time Rename 'reset skater' to 'return skater' Energy Vs. Position plot: fix horizontal range rename 'title' to 'energy vs. position' horizontal axis label Earth background is kPhet Make object mass switchable. Add a control for coeff of restitution. Fix horizontal range on Energy vs Position graphs. Turned model and view upside down. Paint like Jupiter/Earth/Moon/Space. Change Locale (background & gravity). The ground can be driven on and only bounced off. -Changes for 11-14-2005, 0.10 Added performance enhancements for energy-position graph Added a vertical location indicator in energy-position graph Bugfix: A bounce entails a loss of energy (which I didn't intend). Add coefficient of restitution. -Changes for 11-8-2005, 0.09 Improved performance on energy vs. position plot. Data points fade on the energy vs. position plot. Gravity is user-settable. Better center of mass for the skater. -Changes for 11-7-2005, 0.08 1. Fixed a bug in the friction update 2. Switched to Runge-Kutta 4th order differential equation solver. 3. Max selectable coeff of kinetic friction is 0.04 4. Added plot of energy vs position (experimental, not optimized). 5. Move labels below bar chart. 6. Colorize bar chart labels. 7. Added thermal energy to plot 8. Fixed a bug that prevented the splash screen on startup. 9. Minimized download size. -Changes for 0.07 and earlier Record history dots Measuring tape Man can be re-centered without restarting application. pie chart Area is proportional to energy (not Diameter)