# request: boolean Visible[String objName]

nidzela shared this idea 12 years ago
Under Consideration

i've tried to find this somewhere in the forums, and finally i think it doesn't exist yet.

it would be a quite cool walkaround to have a "visibility command" within GeoGebra, so that you could use it inside a condition (for example, in the advanced tab). this way you could (more) easily set a new condition for an object depending on the visibility of another.

1

I am not to clear on your meaning, we can do that at this time for most things in the advanced tab. A little more detail on your part should clarify the request. I currently use conditions in the advanced tab with check boxes to change visibility of texts. See the attached example I recent put up for my students on Memory Triggers in trigonometry.

Tony

PS: I would like to find other Memory Triggers for math as well. Ideas are welcome. Most of these were found on YouTube.

https://ggbm.at/548093

1

HI

Control visibilty of an object based on another already exists in the properties of the object itself. For example a point A (or a picture, or a polygon,..)can be displayed if his abscissa is equal to the abscissa of an another point B or if his distance to B is less than a value you wantand witohout Html but with geogebra

Within Geogebra but in javascript in html: ggbApplet.setVisible(object,true or false)

or setLabelVisible(name, booléen)to see String objName

Daniel

1

oh, well... my request was not clear enough. i'll try with an example, then.

let's say there is a point A with some long visibility condition:

Zoom ∧ (FrRel ∨ Prob) ∧ n5 + n6 + n8 + n9 ≟ 0 ∧ M > 0

then i want to hide a point B that depends on A. imagine something like "only one of them has to be seen", for example, but could be "worse".

• first general problem: the condition usually becomes too large for the tiny textbox. many times i find myself copy-pasting it outside, then inside again when correct. this could be ammended, also.
• second particular problem: of course it is possible to write ¬(Zoom ∧ (FrRel ∨ Prob) ∧ n5 + n6 + n8 + n9 ≟ 0 ∧ M > 0) inside the advanced tab... but what about writing just ¬Visible[A]?

i think that possibility would be great!

1

Hi,

you can also define (auxiliary) boolean

aVisible=Zoom ∧ (FrRel ∨ Prob) ∧ n5 + n6 + n8 + n9 ≟ 0 ∧ M > 0

and then set visibility condition of a to aVisible and for b to !aVisible.

It cetainly won't be added to 4.0 (the deadline was March 1st).

I've added it to the ideas list: http://www.geogebra.org/tra... so we can decidewhether to add it to 5.0 or not.

1

I, too, believe this feature is missing. I could not find a way to solve the following (everyday) problem:

- there is a line g

- there is a line h

- there is the angle alpha between g and h

- I want alpha only to be shown when both g and h are visible.

The way to do this seems to be by setting alpha's conditional visibility to:

Visible[g] AND Visible[h]

But there is no boolean Visible[]! Am i missing something here? This seems to be a standard problem, but I cannot solve it.

Regards,

Rüdiger

1

Hello Noel,

thanks for the reference. This is a JavaScript function available from HTML. I have no HTML file, but a .ggb file: How would I enter this in the Field "Condition to Show Object" under Properties->Advanced?

Whatever I try, Geogebra responds "Unknown command : getVisible".

Regards,

Rüdiger

1

I know this is an old thread, but I could not find the IsVisible functionality in the current version of Geogebra. Am I missing something? Is it implemented yet? I see some comments mentioning a GetVisible command, but I could not find this command either.

(I am trying to count the number of visible elements in a fixed list of objects)

1

Quote: "I am trying to count the number of visible elements in a fixed list of objects"

Only in JS.

getVisible(String objName, int view) in JS-reference