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Overview

The TreeElectric unit provides specialized shapes for creating electronic circuit diagrams and electrical schematics in TeeTree. These shapes represent common electrical components and logic gates.

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Inheritance Hierarchy

TCustomTreeShape
  └── TElectricShape (base class for electric shapes)
        ├── TSolidResistorShape
        ├── TResistorShape
        ├── TCapacitorShape
        ├── TDiodeShape
        ├── TGroundShape
        ├── TSourceShape
        ├── TChasisShape
        ├── TOrGateShape
        ├── TAndGateShape
        └── TLampShape

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Base Class

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TElectricShape

Electric Shape

Base class for all electrical component shapes.
Description: Foundation class for electrical and electronic components. 
TElectricShape = class(TCustomTreeShape);

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Resistors

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TResistorShape

Resistor

Standard resistor with zigzag pattern.
Description: Traditional resistor symbol with zigzag line pattern. Drawing:
  • Horizontal lines at ends (terminals)
  • Six zigzag segments in the middle
  • Total width divided into 8 segments
Usage: 
var
  Resistor: TResistorShape;
begin
  Resistor := TResistorShape.Create(Tree);
  Resistor.Text.Add('1kΩ');
  Resistor.Width := 80;
  Resistor.Height := 30;
end;

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TSolidResistorShape

Solid Resistor

Modern resistor symbol (rectangular box).
Description: IEC/European style resistor symbol. Drawing:
  • Rectangle in the middle (2/3 of width)
  • Terminal lines extending from each end
Usage: 
var
  Resistor: TSolidResistorShape;
begin
  Resistor := TSolidResistorShape.Create(Tree);
  Resistor.Text.Add('2.2kΩ');
end;

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TFuseShape

Fuse

Fuse symbol (resistor box with center line).
Description: Extends solid resistor with a horizontal line through the center. Usage: 
var
  Fuse: TFuseShape;
begin
  Fuse := TFuseShape.Create(Tree);
  Fuse.Text.Add('5A');
end;

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Capacitors

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TCapacitorShape

Capacitor

Standard capacitor symbol.
Description: Two parallel vertical lines with terminal leads. Drawing:
  • Two vertical lines in the center (2-8 pixels apart)
  • Horizontal terminal lines extending from center to edges
Usage: 
var
  Capacitor: TCapacitorShape;
begin
  Capacitor := TCapacitorShape.Create(Tree);
  Capacitor.Text.Add('100µF');
  Capacitor.Width := 60;
  Capacitor.Height := 40;
end;

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Semiconductors

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TDiodeShape

Diode

Diode symbol with triangle and line.
Description: Triangle pointing right with vertical line on the right side. Drawing:
  • Horizontal terminal lines (1/3 of width each end)
  • Vertical line on left
  • Filled triangle pointing from left to right line
Usage: 
var
  Diode: TDiodeShape;
begin
  Diode := TDiodeShape.Create(Tree);
  Diode.Text.Add('1N4148');
  Diode.Width := 70;
end;

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Power and Ground

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TGroundShape

Ground

Ground connection symbol.
Description: Three horizontal lines of decreasing length. Drawing:
  • Vertical line from top to center
  • Three horizontal lines below, each progressively shorter
  • Lines spaced at 1/4 height intervals
Usage: 
var
  Ground: TGroundShape;
begin
  Ground := TGroundShape.Create(Tree);
  Ground.Width := 50;
  Ground.Height := 40;
end;

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TSourceShape

Source/Battery

Voltage source or battery symbol.
Description: Circle with plus/minus terminals. Drawing:
  • Vertical lines extending from top and bottom
  • Circle in the middle
  • Plus sign in upper portion
  • Minus sign in lower portion
Usage: 
var
  Battery: TSourceShape;
begin
  Battery := TSourceShape.Create(Tree);
  Battery.Text.Add('9V');
  Battery.Height := 80;
end;

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TChasisShape

Chassis Ground

Chassis ground connection.
Description: Rectangle with hatched bottom. Default Color: clBlack Drawing:
  • Vertical line from top
  • Rectangle body (2/3 height)
  • Diagonal hatched lines at bottom
Usage: 
var
  Chassis: TChasisShape;
begin
  Chassis := TChasisShape.Create(Tree);
  Chassis.Height := 60;
end;

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Logic Gates

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TOrGateShape

OR Gate

Logical OR gate symbol.
Description: Curved gate shape with two inputs and one output. Drawing:
  • Curved input side (concave)
  • Curved output side (convex)
  • 33 points for smooth curves
Usage: 
var
  OrGate: TOrGateShape;
begin
  OrGate := TOrGateShape.Create(Tree);
  OrGate.Width := 80;
  OrGate.Height := 60;
end;

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TAndGateShape

AND Gate

Logical AND gate symbol.
Description: D-shaped gate with flat input side and rounded output. Drawing:
  • Flat vertical line on left (input side)
  • Semi-circular curve on right (output side)
  • 33 points for smooth output curve
Usage: 
var
  AndGate: TAndGateShape;
begin
  AndGate := TAndGateShape.Create(Tree);
  AndGate.Width := 80;
  AndGate.Height := 60;
end;

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Indicators

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TLampShape

Lamp/LED

Lamp or LED indicator.
Description: Octagon with X pattern inside (from TOctagonShape). Default Color: clYellow Drawing:
  • Octagonal border
  • Two diagonal lines forming X inside (1/5 from edges)
Usage: 
var
  Lamp: TLampShape;
begin
  Lamp := TLampShape.Create(Tree);
  Lamp.Color := clYellow;
  Lamp.Width := 40;
  Lamp.Height := 40;
end;

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Complete Circuit Example

uses
  TeeTree, TreeElectric;

procedure CreateSimpleCircuit(Tree: TTree);
var
  Battery, Resistor, LED, Ground: TTreeNodeShape;
begin
  // Voltage source
  Battery := TSourceShape.Create(Tree);
  with Battery do
  begin
    Text.Add('+9V');
    X0 := 50;
    Y0 := 100;
    Height := 80;
    VertTextAlign := vtaBottom;
  end;

  // Resistor
  Resistor := TResistorShape.Create(Tree);
  with Resistor do
  begin
    Text.Add('220Ω');
    X0 := 150;
    Y0 := 100;
    Width := 80;
    Height := 30;
  end;

  // LED
  LED := TLampShape.Create(Tree);
  with LED do
  begin
    Text.Add('LED');
    X0 := 280;
    Y0 := 90;
    Color := clYellow;
  end;

  // Ground
  Ground := TGroundShape.Create(Tree);
  with Ground do
  begin
    X0 := 360;
    Y0 := 100;
  end;

  // Connect components
  Battery.AddConnection(Resistor);
  Resistor.AddConnection(LED);
  LED.AddConnection(Ground);

  // Customize connections
  with Battery.Connections[0] do
  begin
    Border.Color := clRed;
    Border.Width := 2;
  end;
end;

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Logic Circuit Example

procedure CreateLogicCircuit(Tree: TTree);
var
  Input1, Input2, AndGate, OrGate, Output: TTreeNodeShape;
begin
  // Inputs
  Input1 := TTreeNodeShape.Create(Tree);
  with Input1 do
  begin
    Style := tssCircle;
    Text.Add('A');
    X0 := 50;
    Y0 := 80;
    Width := 30;
    Height := 30;
  end;

  Input2 := TTreeNodeShape.Create(Tree);
  with Input2 do
  begin
    Style := tssCircle;
    Text.Add('B');
    X0 := 50;
    Y0 := 140;
    Width := 30;
    Height := 30;
  end;

  // AND Gate
  AndGate := TAndGateShape.Create(Tree);
  with AndGate do
  begin
    X0 := 150;
    Y0 := 90;
  end;

  // OR Gate
  OrGate := TOrGateShape.Create(Tree);
  with OrGate do
  begin
    X0 := 280;
    Y0 := 100;
  end;

  // Output
  Output := TTreeNodeShape.Create(Tree);
  with Output do
  begin
    Style := tssCircle;
    Text.Add('Out');
    X0 := 400;
    Y0 := 110;
    Width := 40;
    Height := 40;
  end;

  // Connect gates
  Input1.AddConnection(AndGate);
  Input2.AddConnection(AndGate);
  AndGate.AddConnection(OrGate);
  OrGate.AddConnection(Output);
end;

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Component Properties

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Terminal Connections

Electric shapes are designed to connect at their centers by default. For precise connections: 
// Custom connection points
with MyConnection do
begin
  // Use points for precise terminal locations
  Points.Clear;
  Points.Add(FromShape.X1, FromShape.YCenter); // Right center
  Points.Add(ToShape.X0, ToShape.YCenter);     // Left center
end;

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Component Labels

Use text properties to add component values: 
Resistor.Text.Add('10kΩ');
Capacitor.Text.Add('100µF');
Diode.Text.Add('1N4001');

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Wire Styling

Customize connection appearance: 
with Connection.Border do
begin
  Color := clRed;    // Power lines in red
  Width := 2;        // Thicker for power
  Style := psSolid;  // Solid lines for connections
end;

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Shape Registration

Electric shapes are automatically registered in the component palette under the “Electric” tab:
  • Resistor
  • Solid Resistor
  • Fuse
  • Capacitor
  • Diode
  • Ground
  • Source
  • Chasis
  • OR Gate
  • AND Gate
  • Lamp

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Drawing Conventions

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Circuit Layout

  • Power: Top of diagram (red wires)
  • Ground: Bottom of diagram (black wires)
  • Signal Flow: Left to right
  • Components: Horizontal orientation preferred

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Color Coding

// Common wire colors
PowerWire.Border.Color := clRed;    // Positive voltage
GroundWire.Border.Color := clBlack; // Ground
SignalWire.Border.Color := clBlue;  // Signal lines

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Component Sizing

// Typical component sizes
Resistor.Width := 80;
Resistor.Height := 30;

Capacitor.Width := 60;
Capacitor.Height := 40;

Gate.Width := 80;
Gate.Height := 60;

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Complex Circuit Example

procedure CreateAmplifierCircuit(Tree: TTree);
var
  VCC, R1, R2, C1, Transistor, Speaker, GND: TTreeNodeShape;
begin
  // Power supply
  VCC := TSourceShape.Create(Tree);
  VCC.Text.Add('+12V');
  
  // Resistors
  R1 := TResistorShape.Create(Tree);
  R1.Text.Add('10kΩ');
  
  R2 := TSolidResistorShape.Create(Tree);
  R2.Text.Add('1kΩ');
  
  // Capacitor
  C1 := TCapacitorShape.Create(Tree);
  C1.Text.Add('100µF');
  
  // Output (speaker represented by lamp)
  Speaker := TLampShape.Create(Tree);
  Speaker.Text.Add('Speaker');
  
  // Ground
  GND := TGroundShape.Create(Tree);
  
  // Connect circuit
  VCC.AddConnection(R1);
  R1.AddConnection(C1);
  C1.AddConnection(R2);
  R2.AddConnection(Speaker);
  Speaker.AddConnection(GND);
  
  // Position components
  Tree.GlobalFormat.ChildManager.ApplyFormat;
end;

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See Also

Basic Shapes

Fundamental geometric shapes

Flowchart Shapes

Process diagram shapes

UML Shapes

UML diagram shapes

Custom Shapes

Create custom shapes

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