getting color under cursor in 3d mode

General Discussion Other

izumitelj

getting color under cursor in 3d mode

in General Discussion • Other • 1 years ago

Hi all,
Does anyone know if it is possible to get the color under cursor in 3d mode? I couldn't find anything useful about this.

To be precise, I have a sphere centered on canvas with texture ( this is code I will build upon). I want to be able to pick color from texture under cursor or from specific coordinate (say middle of canvas). Creating a color picker in a way.

I don't know if this is possible at all, and would appreciate any suggestions.
Thanks

Replies(6)

jun.jk

Re: getting color under cursor in 3d mode

1 years ago

Since the cursor is limited to x and y, you'll need some other method to change your z value. Then you'll want to translate to the relevant position before you get the color.

izumitelj

Re: getting color under cursor in 3d mode

1 years ago

but even if X and Y are fixed (picking from center of canvas), and Z is constant (the sphere rotates around its center, like globe)... I still don't know how this would be done?

Chrisir

Re: getting color under cursor in 3d mode

1 years ago

hello,

maybe in 2D you can use

myColor1 = get (x,y);

to go 3D maybe

```
float theX = screenX(x, y, z);
```
```
float theY = screenY(x, y, z);
```
myColor1 = get ( theX, theY );

please look it up in the reference:
screenX()
screenY()
get()

Greetings,

Chrisir

jun.jk

Re: getting color under cursor in 3d mode

1 years ago

Nice! I was thinking something like:

translate(0,0,z);

color c = get(x,y);

Chrisir

Re: getting color under cursor in 3d mode

1 years ago

there are also 3D libraries with picking abilities if that's what you need :

http://www.lagers.org.uk/s3d4p/index.html

izumitelj

Re: getting color under cursor in 3d mode

1 years ago

I've just tested some of the your suggestions. I took simple RGBcube example, and then used get(x,y) on top. That did exactly what I wanted! I guess I've made some mistakes when I first tested it. I didn't need screenX and screenY though.