GB_graph

4 nodes, 4 edges, one 3-cycle, 1 face, 1 selected node, 1 text label

Introduction

	Graphs are made of nodes, edges, and faces.
	A node has a size or radius, a shape (round dot, rectangle, custom shape, ...), a color and possibly a color gradient or an image, and a label (text). Nodes are denoted  #0 (first node), #1, ...#last.
	Nodes are connected by edges, or links. An edge between #i and #j is denoted (#i,#j). There is at most one edge between two nodes. An edge is undirected : (#i,#j) is the same as (#j,#i). Edges can be displayed as lines, dotted lines, gradients, arrows, curves or springs.
	A path between two nodes a and b is a sequence of edges (#a,#i)(#i,#j)(#j,#k)...(#m,#b); A n-cycle is a closed path of n nodes from one node to itself : (#a,#i)(#i,#j)(#j,#k)...(#m,#a).
	Cycles may enclose faces, colored polygons. Faces may be drawn with color gradrients, or as 'smoothfaces' using Bezier curves. Faces are automatically found by GB_graph, or user-defined.
	

Survival kit

	Meta keys notation : Cmd-Key denotes either ⌘-Key or Ctrl-Key. Cmd-A and Cmd-a, etc. are the same.
	'A' denotes press the 'A' key = Shift-a, 'b' press the 'b' key, ... 
	ESC is the ESCape key. Alt is the Alt or Option key.
	
	Useful commands :
	• Cmd-z : Undo last operation. GB-graph has an history stack to remember the 16 last graphs. The undoLevel  - 0 to 16 - is displayed in the info area (top left of screen). Press Cmd-z, Cmd-z, Cmd-z, ...to go back in time.
	• 'Z' : clear all and start a new graph (undoable)
	• '?' : show help window
	• ESC : quit help window, quit text editor, stop animations, etc.
	
	

Mouse

	• Click on node : select/deselect node
	• Cmd-click on node : add/remove to/from selection
	
	• Alt-click anywhere : create a new node and connect it to current selection (use 'Backspace' to unlink if needed)
	• Click anywhere : deselect all
	• Cmd-click anywhere : move selection to click location (animated)
	• Click-and-drag anywhere : make a selection rectangle, enclosing nodes to select, then Cmd-a.
	
	The following apply to unselected nodes :
	
	• Alt-click on node : select node and connect to last selected
	• Double-click on node : select node and its closure
	• Click-and-drag : select and move node
	• Maj-click-and-drag : select and move node and its closure (cluster)
	• Alt-click-and-drag : select node and rotate its closure
	

Mouse wheel

	• Menu Preferences|mouseWheel to enable/disable the wheel
	• Wheel to zoom +/-
	• Shift-wheel to rotate +/-
	• Alt-wheel to move left/right (X axis)
	• Cmd-wheel to move up/down (Y axis)
	

Menus

	Menus items allow to launch menu actions : yellow background menus, eg. Faces, or to tune parameters values with sliders; The 'reset' action at the end of a menu resets parameters to default values. Menu are denoted by Name|<item name>. Ex : Nodes|radius
	
	• Click onto a menu name : Nodes,Random,... to open/close it
	• Clicking on a tagged menu name : • Anims,• Screens,.. will open/close its sub-menus.
	• 'm' : close all menus / submenus
	

First steps

Nodes & Shapes

Shapes, variant, sizes

	- Clean everybody : 'Z'
	• NewNode : Add a node somewhere : Alt-click
	- Select it : Click or Cmd-click
	- Select a shape : Nodes|Shape
	- Change its radius : Set Nodes|radius = ...  or keys '1', '2'
	- Select a variant : Nodes|variant
	- Try to set Nodes|rotate, Nodes|extent, Nodes|nColor
	• Goto NewNode.
	

Faces & leaders

	Faces are delimited by cycles of any length > 2. Each face has a leader node which is used to set the face color or gradient.
	• NewFaces : Draw ...
	

Triangles

	- Clean everybody : 'Z'
	• Draw the (D) polygon
	- Unselect all : click anywhere
	- Draw faces : 'F'
	- Operations|QuadsToTriangles
	- Repeat : Operations|TrianglesToTriangles
	- [Add a few gradients] Notation : [... is an optional step]
	- [Try another palette : <space>,<space>,...]
	- Menu Nodes|radius = 0 or Key '0'
	- Menu Nodes|lineColor = 16 = black
	- Menu Nodes|lineWidth = 1 or 2 or 0
	

Operations

Homothety

Homothety (n = 2 : two copies, scale = 0.5 , variant =1 : connect)

Revolution!

	A surface of revolution is a surface in Euclidean space created by rotating a curve (the generatrix) around an axis of rotation. 
	• Draw the generatrix path (G)
	- [insert intermediate nodes : select all, then 'I','I',...]
	- [Set MoreGraphs|variant to the minimal radius Rmin]
	- 
	

Links

GB_graph app

Mail for FAQ, bugs report, etc.