Ball Physics
The ball physics model is meant to do things ... [TODO]
Ball trajectory
The trajectory of a ball can be modeled to be parabolic.
like so: .... [TODO]
Configuration
Prediction parameters
Parameter | Description | Default value |
|---|---|---|
PREDICTION_FRAME | window size for prediction - How far into the future are predctions calculated at most. | 70ms |
PREDICTION_STEP_SIZE | size of the steps for the forward search | 10ms |
REFINEMENT_FACTOR | The prediction step size for the reverse search is | 10 |
with the default values up to 7 predictions are calculated if the ball is not predicted to be in flipper range roughly within the next two frames.
So this number is also the worst case number of predictions calculated during the reverse search part of the prediction process.
Flipper range
The model of the area, where the the flippers can hit a ball is computed from a set of five points. These points are set to real world coordinates in meter
and should not need further adjustment after the camera is correctly calibrated (see World Coordinate System).
The values for the left flipper are set to be symmetrical.
Point# | Description |
|---|---|
1 | center point of the circle that the flippers tip moves o |
2 | highest point a ball can be at when it hits the resting flipper |
3 | lowest point a ball can be at when it hits the resting flipper |
4 | lowest point a ball can be at when it hits the fully triggered flipper |
5 | highest point a ball can be at when it hits the fully triggered flipper |
From these points an area, where the ball is deemed to be hittable, is computed.
Inlane Area
Since the trajectory prediction does not consider collisions in general, we need a different kind of predictions for the inlanes,
i.e. the path feeding a falling ball from the playfield to the flippers, behind the slingshot.
A ball is considered to be in an inlane, when it is in a rectangualar area, with one edge given by the begin of the flipper
and the other by a point at highest, outermost position of the angled part of the inlane.
