Draw 2 lines and get the angle through Autolisp COMMANDS
@ВeekeeCZ Ok. Good to know! I'll try to use commands less. Might make sense why I can't find much for them when searching, ha, ha.
I'm having troubles understanding how the angle is calculated for angle. Below is in image describing the angle I am trying to get. I currently am getting angles to be 90 degrees. I am assuming that I will need to change the UCS in order to get the correct angles from the points? I am trying to understand how the angle is calculated to the x-axis.
@theresa_kewley wrote:
....
.... (setq angle1Line1 (COMMAND "line" point1Tension point2Compression ""));Draw and get Line1 (CAN YOU SET LINE COLOR HERE?) (setq angle1Line2 (COMMAND "line" point1Compression point2Compression ""));Draw and get Line2 ....
Read about the (command) function in the AutoLisp Reference, and you will find that it always returns nil. So you can't do the syntax above and get anything stored into your angle1Line1/2 variables. You can do it this way [whether you use (command) or (entmake{x})]:
....
(COMMAND "line" point1Tension point2Compression ""); Draw ...
(setq angle1Line1 (entlast)); ... and get Line1
....
And no, you can't do the color of the Line within the command, but you could either set the CECOLOR System Variable before you draw it [but then you need to set it back afterwards], or change its color after it's drawn, by several methods including a CHPROP command, imposing a color override in entity data, applying it as a VLA property, or maybe the simplest:
(setpropertyvalue (entlast) "Color" YourDesiredColor)
@theresa_kewley wrote:....
.... (setq angle1 (COMMAND "MEASUREGEOM" "Angle" angle1Line1 angle1Line2 ""));get Angle 1
The MEASUREGEOM Angle option won't accept entity names, but requires picking a point on something, maybe because the returned value could be different depending on where you pick on it. But the angle can be measured this way [without even drawing the Lines]:
(command "MEASUREGEOM" "Angle" "" point2Compression point1Tension point2Compression "_exit")
And it shows you the result in degrees -- no need to convert radians. However, I'm not sure how to put that into a variable, since (command) returns nil. There's a LASTANGLE System Variable, but this result does not go into that.
A complication here is that you want an angle between Lines in the Z direction, whereas the (angle) function works only in the XY plane of the current UCS. So a calculation is probably needed, and it does not require changing the UCS -- Pythagoras is your friend.
@Kent1Cooper wrote:A complication here is that you want an angle between Lines in the Z direction, whereas the (angle) function works only in the XY plane of the current UCS. So a calculation is probably needed, and it does not require changing the UCS -- Pythagoras is your friend.
Actually, a little trigonometry can do it, without bothering Pythagoras. After the establishment of the point1Tension / point1Compression / point2Compression variables in Message 1, and assuming the point2compression point is above [as in your image, but could also be below] both the point1 locations, then:
(setq p1T point1Tension p1C point1Compression p2C point2Compression); [simplify variable names for use below]
(setq
verC (- (caddr p2C) (caddr p1C))
verT (- (caddr p2C) (caddr p1T))
horC (distance p1C (list (car p2C) (cadr p2C) (caddr p1C)))
horT (distance p1T (list (car p2C) (cadr p2C) (caddr p1T)))
angC (atan (/ verC horC))
angT (atan (/ verT horT))
angbetween (abs (- angT angC))
)
(prompt (strcat "\nAngle between lines is " (angtos angbetween) "."))
That reports the angle in whatever your current angular Units mode and precision settings are. The Lines are not needed to find the angle, though you can have them drawn if you want.
If the point2 apex location might sometimes fall vertically between the Z coordinates of the two point1 locations, it could be made to check for that, and if that's the case, the angle between would be the sum of the two calculated angles:
....
angbetween (+ angT angC)
....
