Lines getting created kinda crazy

[saim]

I have this goal:
Draw, in a 3D view, a line from a point (given by the user) to the ground (Z = 0) and, on the ground, draw a red "x", with the lines intercepting on the edge of the first line. Should be simple. In fact, it was, here, let me show what I did:
 

(defun c:gline( / p1);
    (setq p1 (getpoint "\nPick a point"));
    (drawxis p1);
    (drawgline p1);
)

(defun drawxis(pg / x1 y1);
    (setq x1 (car pg));
    (setq y1 (cadr pg));
    (command "line" (list (- x1 2) y1 0) (list (+ x1 2) y1 0) "");
    (command "chprop" "last" "" "color" "1" "");
    (command "line" (list x1 (- y1 2) 0) (list x1 (+ y1 2) 0) "");
    (command "chprop" "last" "" "color" "1" "");
)

(defun drawgline(pg / x1 y1);
    (setq x1 (car pg));
    (setq y1 (cadr pg));
    (command "line" (list x1 y1 (caddr p1)) (list x1 y1 0) "");
)

It works more often than not, but sometimes the lines go crazy - and I only did a few tests. The lines don't end up aligned as simply as I would expect, they slitghtly diverge on one or another axis (all lines, all axis, never too much).
I thought it might because of a "relative" coordinate entrance, but that would ALWAYS be a problem, not occasionally.
Any thoughts on why this is happening and how to fix it?

[dlanorh]

43 minutes ago, saim said:

I have this goal:
Draw, in a 3D view, a line from a point (given by the user) to the ground (Z = 0) and, on the ground, draw a red "x", with the lines intercepting on the edge of the first line. Should be simple. In fact, it was, here, let me show what I did:
 

(defun c:gline( / p1);
    (setq p1 (getpoint "\nPick a point"));
    (drawxis p1);
    (drawgline p1);
)

(defun drawxis(pg / x1 y1);
    (setq x1 (car pg));
    (setq y1 (cadr pg));
    (command "line" (list (- x1 2) y1 0) (list (+ x1 2) y1 0) "");
    (command "chprop" "last" "" "color" "1" "");
    (command "line" (list x1 (- y1 2) 0) (list x1 (+ y1 2) 0) "");
    (command "chprop" "last" "" "color" "1" "");
)

(defun drawgline(pg / x1 y1);
    (setq x1 (car pg));
    (setq y1 (cadr pg));
    (command "line" (list x1 y1 (caddr p1)) (list x1 y1 0) "");
)

It works more often than not, but sometimes the lines go crazy - and I only did a few tests. The lines don't end up aligned as simply as I would expect, they slitghtly diverge on one or another axis (all lines, all axis, never too much).
I thought it might because of a "relative" coordinate entrance, but that would ALWAYS be a problem, not occasionally.
Any thoughts on why this is happening and how to fix it?

 

Perhaps this line

 

(command "line" (list x1 y1 (caddr p1)) (list x1 y1 0) "");

 

Should be

 

(command "line" (list x1 y1 (caddr pg)) (list x1 y1 0.0) "");

Since p1 when passed in becomes pg, and IMHO reals should always be reals and not integers 

Edited July 26, 2019 by dlanorh

[Tharwat]

Hi,

One of the most important things when you intend to use commands is that to disable the system variable OSMODE then reset back once your program finishes or ends.

[saim]

That's it!!!

 

First, I really missed that "p1/pg" part. I use different variable names just to make sure the variable is being passed correctly (otherwise, the program should crash when running). I probably made some tests where I defined "p1" as global and then, the problem got masked out.

 

AND yes, setting osmode to 0 fixed the other lines. Didn't think that even when i input the values the snapping would snap, but it did.

 

Thanks, guys!

 

Btw: is 0 readed as an integer? I thought that all numbers were trated as reals, regardless how you putted them on code.

 

Edited July 26, 2019 by saim

[Tharwat]

1 hour ago, saim said:

Btw: is 0 readed as an integer? I thought that all numbers were trated as reals, regardless how you putted them on code.

Using either of the two forms 0 or 0.0 would be the same in coordinates so you can pick the one you desire in this case.

[BIGAL]

Saim

 

Be careful in math functions 3 is different to 3.0 you will find that using an integer with a real can end up with an integer answer ie no decimals.

 

 (/ 16 3)
5

(/ 16 3.0)
5.33333333333333

Edited July 27, 2019 by BIGAL