I Is there a way to calculate this transformation?

AI Thread Summary
Calculating the distance traveled by a ball from a transformed perspective, such as a cylindrical coordinate system, involves determining the angle (θ) and the radial distance (r) from the observer's viewpoint. While θ can be easily identified, calculating r is more complex and may require knowledge of the ball's diameter and the distance to nearby landmarks like the tree-line. Trigonometry can be applied to find r, assuming a flat surface. The perspective view complicates measurements, as it distorts the dimensions of the polo field. Accurate calculations depend on the observer's position and the direction of the ball.
wirefree
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Imagine a helicopter view of a Polo ground. It's length & breadth are known.

Screenshot_20240316-165049.png



Now you are seated where the blue dot is. Your view is such:

IMG_2024-03-16-16-48-17-200~2.jpg


How do mathematicians calculate the distance travelled by a ball from the second perspective?

From the top view, this would be trivial.

But now your view is transformed.
 
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I think of the second prespective in cylindrical coordinates (r,θ). θ is “easy” to determine, r is more difficult. In a perfect world, one could measure the diameter of the ball to determine its distance. There are other experimental techniques, but I am unsure exactly what you are looking for.
 
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Suppose the eye-point location is at the center of the polar coordinates (##r_{eye}=0##) and the angle, ##\theta##, of the polar coordinates of the ball are known. The distance to the ball location, ##r##, remains to be determined. Assuming a flat earth, ##r## can be calculated using trigonometry. You would need to know the distance to the tree-line. That tree-line has sides and its distance would require some calculations that depend on the direction.
 
Frabjous said:
I think of the second prespective in cylindrical coordinates (r,θ). θ is “easy” to determine, r is more difficult. In a perfect world, one could measure the diameter of the ball to determine its distance. There are other experimental techniques, but I am unsure exactly what you are looking for.
Here's a view:

Untitled1.png



You see how the perspective view squashes the 160yd width of the polo field.
 
FactChecker said:
Suppose the eye-point location is at the center of the polar coordinates (##r_{eye}=0##) and the angle, ##\theta##, of the polar coordinates of the ball are known. The distance to the ball location, ##r##, remains to be determined. Assuming a flat earth, ##r## can be calculated using trigonometry. You would need to know the distance to the tree-line. That tree-line has sides and its distance would require some calculations that depend on the direction.

I am interested in following your suggestion. Please annotate as briefly as convenient, Sir.
Untitled2.png
 
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