Topic: Coordinates in the triangle

[velasquez]

Nicely done Lee, direct and concise...
This one works for any 3d points

Thanks Stefan, in hindsight that makes more sense. 

Interesting stuff, no doubt. But I don't understand. I see a green and a yellow line that are not parallel to any of the magenta lines.

The yellow line and a green line are to show the location of the coordinates that I need to find. The angle between these lines is always 90 degrees.

I assumed that P3-P1 was parallel to P2-XPTO; without this assumption, any point on the circle with diameter P1-P2 meets your criteria -



Hence there would be infinite solutions, as kirby correctly notes.

Hello lee
Is there a way to find just the point at the intersection of the lines that I marked in your image?

[Lee Mac]

Hello lee
Is there a way to find just the point at the intersection of the lines that I marked in your image?

Assuming the orange horizontal line is parallel to the base of the triangle, this is what my code (and Stefan's code) will give you.

[velasquez]

Hello lee
Is there a way to find just the point at the intersection of the lines that I marked in your image?

Assuming the orange horizontal line is parallel to the base of the triangle, this is what my code (and Stefan's code) will give you.

Hello Lee
Assuming the base of the triangle is not parallel to the orange horizontal line how can I compute the xpto point?

[ribarm]

(setq xpto (list (car p1) (cadr p2)))
(princ xpto)

[ronjonp]

(setq xpto (list (car p1) (cadr p2)))
(princ xpto)

I thought the same thing too but from the other examples it won't work.

[Lee Mac]

Is there a way to find just the point at the intersection of the lines that I marked in your image?

Assuming the orange horizontal line is parallel to the base of the triangle, this is what my code (and Stefan's code) will give you.

Assuming the base of the triangle is not parallel to the orange horizontal line how can I compute the xpto point?

Then the problem requires additional constraints - please refer to my earlier post.

[velasquez]

Thank you to everyone who helped me.