Grid Region Logic

Logic for Grid Regions

We can determine logic to define grid-regions within a nested for-loop, and we can display certain patterns within these regions using this logic.

Patterns in Grid Regions

Logic for Displaying Patterns in Regions

The code below shows that we can use for-loop logic that looks at the index values: i, j to determine 4 regions where we can display different shapes to develop a more interesting pattern.

Region Logic:

• Region 1: i < rows/2 && j < cols/2

• Region 2: i < rows/2 && j >= cols/2

  • Even Cells: (i+j) % 2 == 0

• Region 3: i >= rows/2 && j < cols/2

  • Even Cells: (i+j) % 2 == 0

• Region 4: i >= rows/2 && j >= cols/2

Region Design Patterns: Fill grid cells

• Region1: display Shape1

• Region2: display Shape2, if even cells, display Shape1

• Region3: display Shape2, if even cells, display Shape1

• Region4: display Shape1

Example Code for the Region-Based Design Patterns

void displayShapeList( PShape[] _shapes1, PShape[] _shapes2, float cellSize, int rows, int cols) {
  int xPos =0;
  int yPos = 0;
  int shapeIndex=0;
  for ( int i=0; i<rows; i++) { 
    for (int j=0; j<cols; j++) {  //draw a shape in each column
      if(  i < (rows/2) && j < (cols/2)  ){  //region 1
          shape(_shapes1[shapeIndex], xPos, yPos);   //display the shape
      }
      else if( i >= (rows/2) && j >= (cols/2)){  //region 4
         shape(_shapes1[shapeIndex], xPos, yPos);   //display the shap
      }
      else if( (i + j) % 2 == 0 ){  //even position in region 2,3
        shape(_shapes1[shapeIndex], xPos, yPos);   //display the shap
      }else{ //remaining positions in region 2, 3
        fill( 50);
        rect(xPos, yPos, cellSize, cellSize);
        shape(_shapes2[shapeIndex], xPos, yPos);   //display the shap
      }
      xPos += cellSize;
      shapeIndex++;
    }
    xPos = 0;
    yPos += cellSize;
  }  //end outer for loop
}   //end displayShapeList