Snooker Potting Angle Calculator (SPAC)

Help you Find that Sweet Spot & Line of Aim

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Version 1.03

February 2021

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Aim Right and Make Successful Pots for the Right Reason


Good snooker & pool ball potting calls for perfect orchestration of basic techniques, cue actions and aiming skills. The knowledge of aiming & sighting is probably one of the most fundatmental and important technique in beginners' successful potting:- if a learner cannot aim & sight correctly and consistently he is actually starting from behind. Sadly this knowledge is commonly ignored or misinterpreted.


Many players believe that, for any angled shot, the point on the object ball furthest from and directly opposite the chosen pocket is the correct contact point (POC as in below picture). So many players look for this point (POC) & aim their cue towards this point. The result is inconsistent potting - sometimes it works, sometimes it doesn't. Why would this be? Many players run their cue through the cue ball pointing towards the point of contact (POC) as in the yellow line below. This will NOT create the correct contact between cue ball and object ball (if they pot the ball this way they actually made an error somewhere!). To pot the ball the Line of Aim must be offset to establish the correct point of contact (POC) between cue ball and object ball. Instead of running the cue/cue ball along the yellow line they should run the cue/cue ball along the purple line as in below!


potting angle explained


"So okay" I heard you say, "Next time I will aim my cue slightly off to the POC and I will be alright.". I hope it is this simple. The fact is, the amount of offset between the yellow line and the purple line above varies with the potting angle. The relationship is not linear and this is why establishing the correct Line of Aim is so difficult to master. So for any angled pot, in order to make the object ball travels in the desired direction, the cue ball must travel towards the centre of the Virtual Ball (CVB) - purple line - and NOT pointing towards the actual contact point on the object ball, POC. The cue must travel along the correct cue direction (purple line) in order to move the object ball towards the target (along Object Ball Direction).


In real games it is not easy to visualize this Line of Aim, but if this concept is well understood and applied, potting precision is sure to improve. To help snooker players visualize this cue direction (Line of Aim), Snooker Potting Angle Calculator (SPAC) was developed to illustrate this invisible Line of Aim and its relationships with POC and Object Ball Direction. By interacting with SPAC, users should be able to learn how these important lines are drawn in relation to the balls, and if they can apply the same principle into their game, that is, by developing a habit to look for and establish the correct Line of Aim, aiming improvement will follows and you will be amazed that all those times you spent on practising snooker aiming does not take you this far.


SPAC provides a precise answer to finding that sweet angle that will pocket the object ball, but SPAC will not help if they don°¶t have the solid techniques to perform the technical tasks in straighter delivery of the cue. Therefore SPAC should only be used as a self study tool or an assistive learning tool, it will never replace a coach who can teach so much more about the game and strategy of snooker.

What is Snooker Potting Angle Calculator (SPAC)?


Ideal for all levels of snooker players & coaches, SPAC is an useful tool for examining the relationship between cue direction (Line of Aim) and Object Ball Direction. By interacting with SPAC it is easy to see the exact cue direction (Line of Aim) that will pocket the object ball. Snooker aiming is difficult because the actual point of contact (POC, between Cue Ball and Object Ball) is usually not where you cue should aim at! That means your cue is theoretically aimed at a point which you cannot see with your eyes. SPAC takes the guesswork out of pin-pointing this invisible point and by training your brain to (mentally) draw the two most important lines like SPAC does, aiming improvement is sure to come.


SPAC allows users to find the correct potting angle and cue direction for any shot involving a cue ball, an object ball and a target. Because I found that the few traditional aiming methods do not provide enough accuracy to move my game forward, I decided to develop SPAC to illustrate the important aiming clues that are often misunderstood or ignored by snooker players. Users will find the way SPAC present the aiming clues are far more accurate than what are usually known as quarter ball, half ball, three quarter ball, etc. SPAC emphasizes pin-point aiming accuracy but for those who are familiar with Virtual Ball (VB) sighting they will find SPAC instantly familiar because VB is also illustrated in its user interface. The key to successful potting is to determine the correct cue direction (Line of Aim) and SPAC trains your brain to understand how the line is established so you can apply the same technique in your games.


SPAC is NOT a total solution to successful potting, because potting is not only about correct aiming, one also need a perfect cue action to make it happen. However, if you can aim with pin-point precision and you miss the pot, at least you know your aiming is not the cause and you have a better chance to locate the cause and fix the problem with the right solution.


Finally, SPAC is not a fancy 3D simulator or a game of some sort, if you are looking for some true-to-life snooker simulation & animation experience you will be disappointed. SPAC is only an assistive tool to help you get into the habit of pin-point precision aiming by establishing the correct Line of Aim in all shots. You physically ability to perform good, straight cue action is as important as anything else. In this regards serious players should get a coach to address those techniques.

Using SPAC


Using SPAC is very straightforward:

  1. Select a Table

Choose one of the four tables shown on bottom left corner. If a table is labelled as "Draggable" then you are able to "move" the table by dragging on its green area.



  1. Move the Target / Object Ball / Cue Ball

Target is where the object will stop at (or pass through). It is the red-dot you see on screen. You would normally wish move the target to one of the pockets. Object Ball is the ball to be struck by the cue ball. It is one of the red/colour balls. You would normally move the Object Ball to somewhere near the pockets. Cue Ball is the white ball which your cue would strike on. Position the cue ball anywhere on the table.



  1. Experimentation & Observation

Randomly position the Cue Ball/Object Ball/Target to reveal the actual angles & cue directions required to make the Object Ball travel in the intended path (towards the target). Don't move things around aimlessly °V Set up different scenario and train your brain to "think" & "draw" lines like SPAC does. Learn to find the Line of AIM by visualising the Virtual Ball Centre (CVB). This is the point where your cue must aim at.


While moving the balls around you should also observe how the virtual ball re-positions, and how the coloured lines are drawn on the table:


Red Line: Object Ball Direction: the path which the Object Ball will travel on. Normally you would want the object ball to travel towards the Target.


Purple Line: Cue Ball direction: the path the Cue Ball will travel on. It is commonly referred to "Line of Aim". This is the exact direction which you cue should slide along.


Yellow Line: Points of Contact (POC) °V the exact point where the collision happens on the Cue Ball/Object Ball.


You will also note the value of the acute angle (in degrees/radians) being updated on top part of the screen as you move any of the three objects on the table.



If words like "Full Ball", "Quarter Ball" are in your dictionary then you should also study the graphics on the bottom right-hand corner of the screen - there is an interactive illustration showing the projection of the Cue Ball onto the Object Ball. It demonstrates the overlap required to pot the Object Ball. While perspective error makes Cue Call and Object Ball appears difference in size in actual games, one thing that doesn°¶t change is the Virtual Ball centre (shown as Centre of the semi-transparent call) in the graphics and this is where the cue should aim at. The yellow vertical line illustrates where the impact actually happens on the Object Ball.



Finally, note that SPAC is only an aid and it only calculates the answer for you, but it does not teach you what to do to make a perfect shot. Users of SPAC should learn the technique by observation (i.e. position of contact point with respect to cue direction, acute angle value between balls, and so on). Carefully watch the relationship between balls with an open mind will help eliminate any pre-justice that was accumulated by personal experience learnt from a combination of wrong sighting, cueing, cue action, etc. To those who expect SPAC to turn them instantly into a great potter instantly they will be disappointed °V Unless they develop a habit of establishing a correct Line of Aim (as SPAC does for you) otherwise SPAC will not be of help.


A good way to use SPAC is to interact with it a few minutes everyday, so as to develop a habit of Line-of-Aim searching. Apply this principle on your next game, the game after, and so on, not too far in the future you will feel comfortable with working with these invisible lines in your game. Remember, a correct Line of Aim on every shot will improve your potting ability.


SPAC is not designed to be a full snooker simulator or game or anything fancy. It is a simple but inspiring tool that conveys the subtleties that are required to play your shots in precision. Frequent reference to SPAC will help gaining better potting accuracy only if you understand and apply the aiming technique illustrated in SPAC. SPAC is an ongoing development and more features may be added upon users°¶ feedback. Please continue to support SPAC. Thank you.


Sample Screen Captures of SPAC


* the name has many variations. To my knowledge these terms are commonly interchangeable: Virtual Ball, Ghost Ball, Phantom Ball, Imaginary Ball, etc

Do I need SPAC if I am already a good potter?


I always believe that no matter how experienced you are at this game it won°¶t hurt to apply another technique into your game play. A lot of people pots well but they are not good players. What differentiate these people from good players? I have a pair of simple formula below that may help explain this:


Successful Pot = Correct Cueing + Correct Grip + Correct Approach + Correct Bridge + Correct Stance + Correct Potting Angle + Correct Sighting + Correct Cue Action


Successful Pot = Wrong Cueing + Wrong Grip + Wrong Approach + Wrong Bridge + Wrong Stance + Wrong Potting Angle + Wrong Sighting + Wrong Cue Action


The above doesn°¶t make sense, does it? How could someone who did the wrong things can get the ball potted? The fact is that many of us fall into this category! The difference that separates these two types of players is CONSISTENCY. Good players has high potting accuracy (> 90%) while average player has low potting accuracy (<50%). Doing the wrong things may give you some good results occasionally, but it never gives you the consistency required to become an outstanding snooker player.


So if sighting and potting is never a problem to you, I sincerely congratulate you - but if you have room for improvement, then SPAC will inspire you to achieve better accuracy. Furthermore, by setting up different scenarios in SPAC, you will understand why some pots are more difficult to play than the others. So SPAC can be used as an instructional tool to help people understand the art of potting.


Snooker Potting Angle Calculator (SPAC) for Windows OS

Purchase Instruction


Snooker Potting Angle Calculator (SPAC) can be purchased for ĘG10. After purchase we will send you a download link (the time required will depend on your time zone, but should be no more than a few hours).


We accept popular payment methods such as Paypal, Credit Cards, bank transfer, etc. To order online please click the "buy now" button below (credit card/paypal)


Note: SPAC runs on Windows 10, 8, 7, Vista, XP, 2000, 98, ME, NT. SPAC is guaranteed to be free from virus, spyware, malware and all sorts of nasty things.



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