sketch.js

// Daily Sketch for 2021-03-28
// Ram Narasimhan.
/*
 Goal 1: Rectangular shapes. Points on the Perimeter. Internal points.
 Path Following a shape
  Goal 2: Draw 'ripples' that start from one edge and go to the other, circumscribing rectangles
*/

let palette = []
const cnv = {
  xMargin: 30,
  yMargin: 30,
}

const gr = {
  rows: 20,
  cols: 20
}
const nShapes = 2;

function setup() {
  createCanvas(860, 860);
  background("#d3d3d3");
  //background("#0F0F0F");
  //background(seablue);
  draw_border(20); //rn_utils.js
  palette = red_orange; //colors.js
  palette = replicate(palette, 10)

  cnv.height = height - 2 * cnv.yMargin
  cnv.width = width - 2 * cnv.yMargin
  fill(20)
  rect(cnv.xMargin, cnv.yMargin, cnv.width, cnv.height);
  grid = new Grid(gr.rows, gr.cols, cnv.width, cnv.height, cnv.xMargin, cnv.yMargin);
  stroke(255);
  //renderGridPoints(grid.points) // rn_grid.js
  let alphaValue = 100;
  for (let echo = 0; echo < nShapes; echo++) {
    colr = color(random(palette));
    colr.setAlpha(alphaValue);
    rct = createRectComplex(grid, colr, echo);
    renderRectComplex(rct, grid, colr);
  }

  // Draw the lines...
  for (let rhy = 0; rhy < grid.rows; rhy++) {
    sWest = grid.getGPt(0, rhy); // west wall
    sEast = grid.getGPt(grid.cols, rhy); // east wall
    if (sEast.free) {
      createAndRenderPath(sEast, sWest) //from R to L
    }
    if (sWest.free) {
      createAndRenderPath(sWest, sEast) // from the right to left
    }

  }
}

function createAndRenderPath(source, target) {
  rip = new Ripple(source, target, grid)
  rip.createPath(grid) // creates a single path
  rip.render(random(palette));
}




function createRectComplex(grid, colr, num) {

  // Add a while loop for min number of tries...

  rw = grid.xStep * (1 + int(random(10)));
  rh = grid.yStep * (1 + int(random(10)));
  gx = int(random(grid.cols));
  gy = int(random(grid.rows));
  r = grid.getGlobalCoords(gx, gy) // nw corner
  if ((r.x + rw < grid.width) && (r.y + rh < grid.height)) {
    bbox = getRectBbox(r, rw, rh);
    gridPts = getInternalGridPoints(bbox, grid.points)
    print(gridPts)
    for (g of gridPts) {
      if (g.col == gx)
        strokeWeight(10)
      point(g.x, g.y)
    }

    return ({
      x: r.x,
      y: r.y,
      width: rw,
      height: rh,
      id: num
    })
  }
}

function renderRectComplex(rct, grid, colr) {

  //print(r.x + rw, grid.width)
  if ((r.x + rw < grid.width) && (r.y + rh < grid.height)) {
    push();
    noFill();
    if (colr) {
      fill(colr)
    }
    translate(rct.x, rct.y);
    rect(0, 0, rct.width, rct.height);
    pop();
  }

}


function getRectBbox(r, rw, rh) {
  try {
    return {
      xMin: r.x,
      xMax: r.x + rw,
      yMin: r.y,
      yMax: r.y + rh
    };
  } catch (err) {
    print("Rect NW", r, "hull", rw, rh)
  }
}


function getInternalGridPoints(bbox, gridPts) {
  // grid points inside bbox
  gridBox = [];
  for (g of gridPts) {
    if ((g.x <= bbox.xMax) &&
      (g.x >= bbox.xMin) &&
      (g.y <= bbox.yMax) &&
      (g.y >= bbox.yMin)
    ) {
      g.free = false;
      gridBox.push(g)
    }
  }
  return gridBox
}