Example files that accompany this section: http://grasshopperprimer.com/appendix/A-2/1_gh-files.html
In the color wheel, hue corresponds to the angle. Grasshopper has taken this 0-360 domainand remapped it between zero and one.
By dividing the Hue domain (0.0 to 1.0) by the number of segments desired, we can assign a hue value to each segment to create a color wheel.
In this example, we will use Grasshopper’s domain and color components to create a color wheel with a variable amount of segments.
|01.||Type Ctrl+N (in Grasshopper) to start a new definition|
|02.||Curve/Primitive/Polygon – Drag and drop a Polygon component onto the canvas|
|03.||Params/Geometry/Point – Drag and drop a Point Parameter onto the canvas|
|04.||Right-Click on the Point Component and select set one point|
|05.||Set a point in the model space.|
|06.||Connect the Point Parameter (Base Point) to the Plane (P) input of the Polygon component|
|07.||Params/Input/Number Sliders – Drag and drop two Number Sliders onto the canvas|
|08.||Double-click on the first Number Sliders and set the following:
Lower Limit: 0
Upper Limit: 10
|09.||Double-click on the second Number Sliders and set the following:
Lower Limit: 0
Upper Limit: 100
|10.||Connect the Number Slider (Radius) to the Radius (R) input of the Polygon component
When you connect a number slider to a component in will automatically change its name to the name of input that it is connecting to.
|11.||Connect the Number Slider (Segments) to the Segments (S) input of the Polygon component|
|12.||Curve/Util/Explode – Drag and drop an Explode component onto the canvas.|
|13.||Connect the Polygon (P) output of the Polygon component to the Curve (C) input of the Explode component|
|14.||Surface/Freeform/Extrude Point – Drag and drop the Extrude Point component onto the canvas|
|15.||Connect the Segments (S) output of the Explode component to the Base (B) input of the Extrude Point|
|16.||Connect the Point Parameter (Base Point) to the Extrusion Tip (P) of the Extrude Point component|
|17.||Surface/Analysis/Deconstruct Brep – Drag and drop the Deconstruct Brep component on to the canvas|
|18.||Connect the Extrusion (E) output of the Extrude Point component to the Deconstruct Brep (B) component|
|19.||Maths/Domain/Divide Domain – Drag and drop the Divide Domain component
The Base Domain (I) is automatically set between 0.0-1.0 which is what we need for this exercise
|20.||Connect the Number Slider (Segments) to the Count (C) input of the Divide Domain component|
|21.||Math/Domain/Deconstruct Domain – Drag and drop the Deconstruct Domain component|
|22.||Connect the Segments (S) output of the Divide Domain component to the Domain (I) input of the Deconstruct Domain component|
|23.||Display/Colour/Colour HSL – Drag and drop the Colour HSL component|
|24.||Connect the Start (S) output of the Deconstruct Domain component to the Hue (H) input of the Colour HSL components|
|25.||Display/Preview/Custom Preview – Drag and drop the Custom Preview component|
|26.||Right click on the Geometry (G) input of the Custom Preview component and select Flatten
See 1-4 Designing with Data Trees for details about flattening
|27.||Connect the Faces (F) output of the Deconstruct Brep component to the Geometry (G) input of the Custom Preview component|
|28.||Connect the Colour (C) output of the Colour HSL component to the Shade (S) input of the Custom Preview component|
For different color effects, try connecting the Deconstruct Domain component to the saturation (S) or Luminance (L) inputs of the Colour HSL component.