Dynamic Colors

In GeoGebra, you can change the color of objects using tab Color of the Properties Dialog. However, you can also have the color of an object change dynamically: Open the Properties Dialog for a certain object whose color you would like to change and click on tab Advanced. There you will find a section called Dynamic Colors with text boxes for the color components Red, Green, and Blue.

Note: In each of these text boxes, you can enter a function with range [0, 1].

Example:

• Create three slider a, b, and c with an interval from 0 to 1.
• Create a polygon whose color should be influenced by the slider values.
• Open the Properties Dialog for the polygon poly1 and enter the names of the three sliders into the text boxes for the color components.
• Close the Properties Dialog and change the values of the sliders in order to find out how each color component influences the resulting color of the polygon.

Note: You could also animate the sliders with different speeds in order to see the color of the polygon change automatically.

The Dynamic Colors section also contains a text box which allows you to change the Opacity of the selected object. You can enter a number ranging in [0,1] (where 0 means transparent and 1 means 100% opaque), as well as a slider, in order to obtain a dynamic opacity. Other numbers will be ignored.

RGB / HSV / HSL

By selecting RGB, HSV, HSL color models from the drop down list at the bottom of the Dynamic Colors section of the Advanced tab of the Properties dialog of the selected object, you can refine the accuracy of your coloring. The default value for dynamic coloring is RGB.