1. Introduction to Grasshopper for rhino

2. Grasshopper Modelling (Parametric) Grasshopper Application
Rhino 3D Modelling
(Static)
Grasshopper Modelling
(Parametric)
Grasshopper Application

3. RHINO VS GRASSHOPPER?
Main Difference between Rhino and GH (Grasshopper) is that GH is a Parametric Tool

4. PARAMETRIC?
Allows us to create geometry from initial parameters and design the relationships they keep. 1
“Make a Cylinder with the following initial Paramaters:”
Located at Point X,Y,Z
Radius of 75mm
Length of 500mm A 1 B C

5. PARAMETRIC?
Allows us to create geometry from initial parameters and design the relationships they keep. 2 2
Move this Initial Geometry using the following Parameters
500mm
In the Y Direction 1 2 A B

6. PARAMETRIC?
Allows us to create geometry from initial parameters and design the relationships they keep.
Using Variables and Algorithms to create a hierarchy of Mathematical and Geometric relationships 3 x
“Scale this Geometry by a Factor of it’s distance moved”
0.5x

7. PARAMETRIC?
Allows us to create geometry from initial parameters and design the relationships they keep.
Using Variables and Algorithms to create a hierarchy of Mathematical and Geometric relationships 1 2
Mathematical and Geometric Relationship
Initial Geometry 1
Initial Geometry 2
Mathematical and Geometric Relationship

8. Using these Rules, Variables and Algorithms allows us to design not only complex geometries but also in a smarter way

9. Using these Rules, Variables and Algorithms allows us to design not only complex geometries but also in a smarter way

15. _GRASSHOPPER
In rhino to Load it

16. Main Menu
Shelves
Canvas Toolbar
Canvas

17. OBJECTS (Geometry) Grasshopper Components Rhino-Referenced Paramaters
Made in Grasshopper
Rhino-Referenced Paramaters
Made in Rhino

18. BASIC STRUCTURE
Grasshopper objects usually can be divided into 5 different parts; Input Tab, Input Option, Body, Output Option, Output Tab. However some objects (eg. Params have 3)
INPUT TAB
INPUT OPTIONS
BODY
OUTPUT OPTIONS
OUTPUT TAB

19. BASIC STRUCTURE EXAMPLE : PARAMETER
Has no Additional Parts because the geometry is defined in Rhino
Input tab + Body + Output Tab
EXAMPLE : COMPONENT
Has Additional Parts (P, R) to define a Geometry.
This case is a Circle (CIR) where user Specifies Position (P) and Radius (R)
Input tab + Input Option + Body + Output Option + Output Tab

20. CONNECTING OBJECTS Click and Hold the Mouse on the Little White Bump
Drag it towards the White Bump to connect to

21. CONNECTING OBJECTS Release to connect.
In this Example we connected a number slider (variable) to the Radius input of a Circle (CIR)

22. OBJECT STATUS
The colour of the Object tells you the status of the Object.

23. OBJECT STATUS
A Red colour, for example, indicates that there is an error (E.G Instead of Inputting a Number for Radius, a letter is given – Since “Dog” is not a numeric value, the status is an error)

24. EXERCISE – Drawing a Circle at specific point
Double Click on the Grasshopper Canvas. This opens up a White box which allows you to Type commands.
Type “Circle” To get the Circle Options
Notice there are two “Circle” Options. A Black logo usually indicates a Param (imported from Rhino) and an Orange indicates a Component (defined in GH)
Select the Orange logo to create a circle Component

25. EXERCISE – Drawing a Circle at specific point
Double Click on the Grasshopper Canvas. This opens up a White box which allows you to Type commands.
Type “Circle” To get the Circle Options
Notice there are two “Circle” Options. A Black logo usually indicates a Param (imported from Rhino) and an Orange indicates a Component (defined in GH)
Select the Orange logo to create a circle Component

26. EXERCISE – Drawing a Circle at specific point
Hovering the mouse over the input tab shows a description of what data is needed. In this case,
Hovering over the “P” Tab indicates that GH expects a Plane. This is where the Circle will be positioned in space. The input of this can also be defined by a Point. By Default, GH sets this to WORLD XY, meaning at the co-ordinate 0,0,0 in rhino on the XY Plane (see next page before panic)
Hovering over the “R” component shows that by default, Grasshopper has defined a Radius of 1 unit (Millimetre or meter, depending on the unit used in rhino)

27. EXERCISE – Drawing a Circle at specific pointY X

28. EXERCISE – Drawing a Circle at specific point
PARAM OBJECT to define a Point
(Notice there are no ‘Input Options’)
Changing the Position of the Circle
We can Change where the circle is created by changing the location of the plane “P”. This can be done in Multiple ways.
By Specifying a Location in Rhino and then Referencing that Back to the GH Component.
By Specifying Co-Ordinates in Grasshopper.
The Difference between these two is that for (1) we will use Params and in (2) we will use Components to define the position
COMPONENT to define a Point
(Notice there are X,Y,Z Options which exist)

29. EXERCISE – Drawing a Circle at specific point
Changing the Position of the Circle : PARAMS
Create a PARAM Point by double clicking on the GH canvas and Typing Point. Alternatively, Use the Toolbars as shown in the picture
After connecting the Point to “P” of the Cir, both Objects Turn Orange. This is because the Point (PT) has not yet been defined.
This means we must now define the point in rhino and reference it back to the PT object

30. EXERCISE – Drawing a Circle at specific point
Changing the Position of the Circle : PARAMS
In RHINO Draw a Point anywhere in space. This will be the point where grasshopper will create the circle
In GRASSHOPPER Right click on the PT object and choose the Option “Select One Point”. This is allowing us to specify the Point from Rhino

31. EXERCISE – Drawing a Circle at specific point
Changing the Position of the Circle : PARAMS
This will automatically take you back to Rhino, where you will be asked to Reference a point. (Notice the Rhino Command : Point Object to Reference)
Select the Point to reference and then will be taken back to Grasshopper

32. EXERCISE – Drawing a Circle at specific point
Changing the Position of the Circle : PARAMS
Now there is a Point as the Position “P” Defined by the Rhino Point with Radius of 1.0 (The default value given by Grasshopper)
To change the position of the Point in space, simply Drag the Point in Rhino. Since this is referenced in Grasshopper it will always create a circle where the point is.

33. EXERCISE – Drawing a Circle at specific point
Changing the Position of the Circle : COMPONENT
The second way to Define a point is to use Grasshopper Components
Double click the GH Canvas and Type “Construct Point” and Select the Point Component
This is Also found under the VEC Tab.
Notice it has 3 Input Options – X, Y, Z. These are the Position of the Point X,Y,Z co-ordinates

34. EXERCISE – Drawing a Circle at specific point
Changing the Position of the Circle : COMPONENT
Connecting the PT component to the Circle now automatically creates a Point in Rhino.
The component does not turn orange this time because by Default, GH has Given default X,Y,Z of (0,0,0). The Circle is now created at this point

35. EXERCISE – Drawing a Circle at specific point
Changing the Position of the Circle : COMPONENT
To Change the Position of the Circle we can change the value of the X,Y and Z co-Ordinates.
To do this, we will use a SLIDER. To Create a slider, double click on the grasshopper canvas and type in the numeric value you would like.
This creates a different type of Object. Moving the White dot left and Right Changes the Value of the Slider. This is a useful tool because it allows you to instantly change values and geometries and form different relationships

36. EXERCISE – Drawing a Circle at specific point
Changing the Position of the Circle : COMPONENT
Using Numeric Sliders, Create a Circle with:
X Co-Ordinate – 13
Y Co-Ordinate – 20
Z Co-Ordinate – 60
And a Radius of 60

37. EXERCISE – Drawing a Circle at specific point
The main difference between the PARAM and COMPONENT is that with the component everything is controlled in Grasshopper.
This can become very useful for more complex scripts where we would like full control on our objects (such as the exact co-ordinate of a point)

38. EXERCISE – Drawing Multiple Circles at Multiple points

39. EXERCISE – Drawing Multiple Circles at Multiple points
Constant Z Position

40. EXERCISE – Making Copies (Move Commands)
The MOVE command (Type Move on Grasshopper) move your Geometry in a Specified Direction and Specified Value. In this Case we will First specify a Direction (Z) by Typing “Unit Z”. This gives a Z Vector Component.
Attaching a Number slider to the input of the vector gives the direction. Since data is never deleted in Grasshopper this makes a copy of the point

41. Making Multiple Copies (Move Commands + Series)
The Series Command (Type Series)
This generates a LIST of Numbers. The input for this component are:
START – The First Number to Be Created. In this case number 10 is Specified
STEP – By how much is the number increasing? In this case, a step of 5 is put. This means that the next number will be added in steps of 5
COUNT – The number of times for this to happen?
The image on the left shows that a LIST of numbers Starting from 10 will be made. 5 will be added to each number, repeating 15 times.
The end result is a series of numbers going 10, 15,20…..
The MOVE command (Type Move on Grasshopper) move your Geometry in a Specified Direction and Specified Value. In this Case we will First specify a Direction (Z) by Typing “Unit Z”. This gives a Z Vector Component.
Attaching a Number slider to the input of the vector gives the direction. Since data is never deleted in Grasshopper this makes a copy of the point

42. Making Multiple Copies (Move Commands + Series)
The Series Command (Type Series)
This LIST can be used to define multiple Z Vectors for moving the point that defines the circle
The MOVE command (Type Move on Grasshopper) move your Geometry in a Specified Direction and Specified Value. In this Case we will First specify a Direction (Z) by Typing “Unit Z”. This gives a Z Vector Component.
Attaching a Number slider to the input of the vector gives the direction. Since data is never deleted in Grasshopper this makes a copy of the point

43. Making Multiple Copies (Move Commands + Series)
Connecting the Moved Points into the Circle Parameter now gives a multiple circles defined by a point moved 15 times in the Z Direction
The MOVE command (Type Move on Grasshopper) move your Geometry in a Specified Direction and Specified Value. In this Case we will First specify a Direction (Z) by Typing “Unit Z”. This gives a Z Vector Component.
Attaching a Number slider to the input of the vector gives the direction. Since data is never deleted in Grasshopper this makes a copy of the point

44. PARAMETRIC RELATIONSHIPS - ATTRACTORS
Parametric Design allows you to form mathematical relationships between objects and automatically changing and defining their shape. For example, in this case we will use an ATTRACTION POINT. This is a point which, depending on how close it is to a geometry, will change it’s shape mathematically
Center Point of Circle
Distance between Center point and Attraction point
ATTRACTION POINT

45. PARAMETRIC RELATIONSHIPS - ATTRACTORS
“Depending on how Far away the Attraction point is from the Centerpoint, Apply a different sized Radius of Circle”

46. PARAMETRIC RELATIONSHIPS - ATTRACTORS
1 Create a Single Point (Slide 42)
2 Move The Point Multiple times in Z Direction (Slide 47-49)
3 Create an Attractor Point (This is a normal Point that lies next to your geometry – make this using the same steps as slide 42) NOTE: Don’t give the same co-ordinates as the other points
4 Distance Tool (Type Distance) This Measures the Distance between Geometries, in this case, the Attractor Point and the Moved Points

47. PARAMETRIC RELATIONSHIPS - ATTRACTORS
5 Multiplication (Optional Step) (Type Multiplication). In this step, it is specifying “Multiple the Distance between each point by a factor of 0.5”. So if the distance between two points is 10mm, the output will be 5mm.
6 Circle Radius - Now use these multiplied values as new radii for the circle. Grasshopper automatically assigns individual radii depending on this multiplication value.

48. PARAMETRIC RELATIONSHIPS - ATTRACTORS
The LOFT (type Loft) command can be used to create a surface from all of these curves. The result is a fully parametric surface which can be defined by all the parameters containing number sliders.

49. PARAMETRIC RELATIONSHIPS - ATTRACTORS
“Depending on how Far away the Attraction point is from the Centerpoint, Apply a different sized Radius of Circle”

50. PARAMETRIC RELATIONSHIPS - ATTRACTORS
“Depending on how Far away the Attraction point is from the Centerpoint, Apply a different sized Radius of Circle”

51. PARAMETRIC RELATIONSHIPS - ATTRACTORS
“Depending on how Far away the Attraction point is from the Centerpoint, Apply a different sized Radius of Circle”

52. “Depending on how Far away the Attraction point is from the Centerpoint, Apply a different sized Radius of Circle”

53. DATA MATCHING
Grasshopper works with Collecting and organizing data. As more and more components become linked together, more and more data is linked together.
The main structure on how data is stored is in Trees and Branches.
The example on the left we can see the Overall Structure:
The surface {0} Tree
4 Curves which Define the Surface {0;0} … – Branch
3 Points in Each Curve that Define the Curve (0) … – Sub Branch

54. DATA MATCHING

55. DATA MATCHING 2 3 1 1 4 2 3 4

56. DATA MATCHING
Want to Draw A line from Point number 3 of Branch 0 to Point Number 1 of Branch 2 3 1

57. DATA MATCHING
Want to Draw A line from Point number 3 of Branch 0 to Point Number 1 of Branch 2

58. “Start With these 3 Lines” “Take Line Number 0”
“Divide Line 0 into 4 Segments”
“Give me Point 3”
“Join Point 3 from Line 0 with Point 1 from line 2”
“Take Line Number 2”
“Give me Point 1”
“Divide Line 2 into 4 Segments”