Pattern

The Pattern class is a wrapper class for geometric shapes based on the Processing PShape object. The Pattern display method has x,y postion input parameters to so that the shape can be displayed at any x,y position. The shapeColor allows programatic modification of the color. The Pattern class allows us to add logic to provide a uniform interface for displaying a variety of PSHape objects, this is necessary because Processing has inconsistent methods for setting the fill and stroke for PShape objects. We'll expand the logic of this class to handle setting fill for all types of PShape objects.

Example Usage:

To create a pattern, first create a PShape object, then pass the PShapeObject into the constructor along with a color that will be used for display

//declare as global objects
Pattern pattern1, pattern2, eraserPattern;

//initialize PShape and Pattern in setup
PShape s1 = createShape( RECT, 0,0,40,40);
pattern0 = new Pattern( s1);  //call constructor

//use similar code to initialize all patterns


//display 
pattern0.fillColor = color(100,100,100); //set fill color
pattern0.display( mouseX, mouseY);

Pattern Class Definition

class Pattern{

  //PROPERTIES
   PShape s;
   color fillColor;
   color strokeColor;

  //CONSTRUCTORS
  Pattern( PShape s ){
    this.s = s;
  }

  Pattern( PShape s, color fillColor){
    this.s = s;
    this.fillColor = fillColor;
  }

  //METHODS
  void display( ){
    s.setStroke( strokeColor);
    s.setFill( fillColor);
    shape( s, 0, 0);
    } 
}//end PatternClass

Pattern objects for Project 3

For this project, you will create 3 global pattern objects:

Pattern pattern0, pattern1, eraserPattern;

Initialize in setup

First you must create 3 PShape objects, then these PShape objects are passed into the Pattern constructor.

//initialize PShape and Pattern in setup
PShape s1 = createShape( RECT, 0,0,40,40);
pattern1 = new Pattern( s1);  //call constructor

Match Patterns to ButtonGroup Buttons in DrawPattern

The code below shows how to connect the ButtonGroup logic with the Pattern logic in the drawPattern( ) function. Notice that we use a temporary variable: Pattern curPattern;, to match-up the activeButton with this temporary variable: curPattern, so that once the switch-case logic has completed, then we display which ever pattern is referenced by the curPattern variable.

void drawPattern( ){

Pattern curPattern = pattern0;  //temporary Pattern variable initially pointing to the pattern0 object.

int activeButton = buttonGroup.activeBtnIndex;

//switch-case control structure determines which pattern corresponds to the current activeButton
switch( activeButton ){
  case 0: //pattern0 and button0
    curPattern = pattern0;

  break;

  case 1: //pattern1 and button1
    curPattern = pattern1; //first we need to set the pattern

  break;

 case 2: //eraser pattern and button
    curPattern = eraserPattern;
    curPattern.fillColor = backgroundColor;
    curPattern.strokeColor = backgroundColor;
 break;

 default:
   println("no match on switch case");

}//end of switch statement logic

  //now display the curPattern
  if( curPattern != eraserPattern){
  //set fill if this is not the eraser
  curPattern.fillColor = color( 150,100,100); //then we can set 
  }
    color - this will use slider values to determine fill
  curPattern.display( ); //display at mouse position
}