When I was testing the batter demo on pitcher’s duel, I observed some behaviour that seemed very odd.  The ball when hit sharply up, would seem to wander around.  Tracking it via its shadow directly below the ball, it would move back and forth over the foul line.  I thought at first this must be a bug, but the realized that is how popups behave.  The ball leaving the bat is severely undercut, and has a lot of backspin; the ball with backspin curves back toward the backstop as it rises.  When it  reaches its apex, though, it reverses direction without reversing spin.  As it falls, what was backspin is  now topspin, and pushes the ball towards the pitchers mound.  The path is thus a loop, and the shadow moves backward, then forward.  Follow the link for a much more detailed explanation.

The ball behaviour explains the way fielders, observed in MLB games, seem to wander back and forth tracking a pop fly.  They aren’t lost, they are just tracking the ball.


Home runs can be as slow as 90 mph off the bat.   This suprised me, at first, as that is the speed of a pitched fastball, and we do not imagine that someone can throw a baseball over the outfield fence from home plate.  However, a good strong arm can reach home plate on a throw from mid center field, and the nearest fence portions, of small ballparks such as Fenway, are as close as 325 ft.

There were two home runs at under 89.5 mph off the bat, but both were in-the-park home runs. 😉 

The fastest home runs were slightly over 122 mph, off the bat.

HitTracker :: Home run tracking and distance measurement 

I like the term ‘Pitchers Duel’, because it describes a type of game that I enjoy thinking about.  Low score, few baserunners, many strikeouts.  Baserunning doesn’t matter much in these games, because rarely does a runner get on base.  The consistency of out-getting makes the contest look like a pure contest between pitchers:  Which pitcher will slip up first, and allow a run to score?

Most baseball fans, to the contrary, like high scoring games.  Baseball game attendence has increased in eras with high-scoring and dropped in low-scoring eras.   So I am considering alternative names for this computer game, that will appeal more to baseball fans.

The pitcher – catcher combo is known as the ‘battery’:

      Battery plus

Various phrases that emphasise the hitting aspect of the game:

       Bat and Ball / Ball and Bat

       Batter Up

       Ball and Stick

A more balanced title that includes both sides of the contest: 

        Hit and Pitch

This title represents the ‘moment of truth’ in each at-bat, where you know you may get only one more pitch. 

        Strike Two

Both batters and pitchers are very concerned about the strikezone, its extents, whether a given pitch is in or out, and how the player fares in the balance of strikes vs balls.

       Strike Zone

       Balls and Strikes

      Ahead of the Count

      Full Count

A facetious, but sorta mean-spirited, option: 

      NOT Barry Bonds

Let me know what you feel is a good choice.

The batter and the pitcher demos have been improved, again, and released.  This time they are both released in the same file. 

 pduel_setup.0.8.1.exe This release is a Windows self-installer, which installs both demos, and includes an uninstaller.

Improvements to the batter include:

  • Bat magnetism, pulls the bat closer to the ‘ideal’ contact position, than your input would have accomplished.  This means more contact with the ball, and more hits.
  • Improvements to the swing timing, so that hits are possible to all parts of the field.
  • A GUI that supports batter-position adjustments, as well as replay and ‘nearest-contact’ inspection.

Improvements to the pitching demo include:

  • A GUI that allows selecting the level of play (MLB, College, HS), as well as the style, intensity, and location of the pitch;  also allows for replays and strike-zone path inspection.
  • Multiple different pitchers, with different arm motions such as overhead and sidearm.
  • Three different pitches, fastball, curveball, slider.

 This game is designed to be a ‘twitch’ skill game, minimizing the influence of random chance in the outcome of each action.  The batters stroke is entirey consequent to how the player ‘aims’, with no random component whatsoever.  The pitcher’s pitch placement interface jitters or flutters, adding some ‘noise’ to the location.  However, at the moment the mouse button is clicked, the pointer points precisely at the pitch destination, so the precision of placement is dependent on your reflexes.

Good things happened this weekend!

Firstly, the Philadelphia Phillies (the local team) qualified for the playoffs by winning the NL East Division, and qualified without the one game tie-breaker. This team does not have the best pitching staff in the league, but complemented by their extraordinary offense, the team is good enough to win the World Series.

Secondly, another major milestone was reached in the development of Pitcher’s Duel. The pitching demo was rereleased. A prior release (in 2005 !) was just an animation demonstration, and did not have an interface to speak of. This release has a GUI and the ability to choose and throw pitches, some retrospection features, and is better looking.

The batter demo is almost done; in fact it was done, but I somehow overlooked releasing it, and now it needs a little sprucing up to match the pitcher demo.   There were a few releases months ago, but without the GUI and some features designed to aid hitting.  This week, I will get it fixed up, and then I will release it as well. I hope to get some good feedback on each, and I may well release an upgrade or two for each, to test any improvements we come up with.

Those are the two largest components of the game. After getting the batter demo online, I will be working on the network library (I have discussed various considerations on this blog before), and then assemble the three components into a playable inter-player game.

Anyway, enough chicken counting….

The demo (version 0.3) is at:

Some description and background is at .


The demo is available as a self-contained Windows installer, and as a source zip.

The source zip needs pygame, pyopengl, and ocemp gui 0.1x preinstalled.


If you are a baseball fan, or a sports-game fan, give it a try.



Plunk Biggio

 This blogger may be a compulsive stathead, but he has a fine sense of humor:

Please note that I have no proof that the Giants are trying to create a 92 foot pitcher, or ever have, and I'm not suggesting they would. But, I think there is reason to believe that if some laboratory, perhaps in the Bay Area, were to help create such a genetic mutant, the Giants would be happy to employ it and see what records it broke. I'm sure the league has no rules against such a thing, and the players association would oppose the creation of any such rules.

Alyssa Milano has a blog about baseball.

 In this post, touch em all: Double Standard , she draws attention to a quote by Derek Lowe about power pitchers doing well in Denver.

That power pitchers (fastball pitchers) do comparatively well there is to be expected.   The low viscosity air affects them favorably, and affects ‘junk’ pitchers unfavorably. 

A pitch experiences less drag and less magnus (curving) force in the lower viscosity air than down at sea level.  So a fastball leaving the pitchers had at, say, 97 mph reaches the plate at a higher speed than the same pitch thrown in a sea-level park, and is less hittable.  A curveball curves less than at sea level, and is consequently more hittable.

 The Rockies are in a rare position where they can constructively build a team to match their ballpark, a team that can consistently outplay everybody else in that park.  The pitching staff should be all power pitchers.  A scan through the Rockies’ roster shows a mix of pitchers, with only one or two of them power pitchers.  This is a shame, as there were some good power pitchers on the market this off-season including B Wagner.

 A good move they did make was to get Willy Taveras from Houston.  He is fast, and an outfielder needs to be fast to cover the large outfield there.

Next Page »