overlapping_rects.py

import cv2
import numpy as np
import itertools
import random as rnd

# TODO:
# swap so that img1 always over img2

def fix_overlap(res, img1, x1, y1, img2, x2, y2):
    h1, w1, _ = img1.shape
    h2, w2, _ = img2.shape

    if y2 < y1:
        x1, y1, w1, h1, x2, y2, w2, h2 = x2, y2, w2, h2, x1, y1, w1, h1

    if x1 < x2:
        for y in range(y2, y1 + h1):
            for x in range(x2, x1 + w1):
                w, h = x1 + w1 - x2, y1 + h1 - y2
                x_, y_ = x - x2, y - y2
                if x_ < (w * (h - y_)) / h - 1:
                    px = tuple(int(c) for c in img1[y_, x_])
                else:
                    px = tuple(int(c) for c in img2[y_, x_])
                res[y, x] = px
    else:
        for y in range(y2, y1 + h1):
            for x in range(x1, x2 + w2):
                w, h = x2 + w2 - x1, y1 + h1 - y2
                x_, y_ = x - x1, y - y2
                if x_ < (y_ * w) / h + 1:
                    px = tuple(int(c) for c in img1[y_, x_])
                else:
                    px = tuple(int(c) for c in img2[y_, x_])
                res[y, x] = px

def fix_overlaps(res, imgs):
    imgs.sort(key=lambda r: r[1])
    for (i1, i2) in itertools.combinations(imgs, 2):
        fix_overlap(res, i1[0], i1[1], i1[2], i2[0], i2[1], i2[2])

if __name__ == "__main__":
    height, width = 800, 1200

    x1, y1 = 100, 200
    w1, h1 = 200, 300

    x2, y2 = 200, 300
    w2, h2 = 300, 300

    x3, y3 = 350, 50
    w3, h3 = 300, 400

    x4, y4 = 550, 000
    w4, h4 = 150, 250

    img1 = np.full((h1, w1, 3), (0, 0, 255), np.uint8) # red
    img2 = np.full((h2, w2, 3), (0, 255, 0), np.uint8) # green
    img3 = np.full((h3, w3, 3), (255, 0, 0), np.uint8) # blue
    img4 = np.full((h4, w4, 3), (0, 127, 127), np.uint8) # brown

    res = np.zeros((height, width, 3), np.uint8)

    res[y4:y4 + h4, x4:x4 + w4] = img4
    res[y3:y3 + h3, x3:x3 + w3] = img3
    res[y2:y2 + h2, x2:x2 + w2] = img2
    res[y1:y1 + h1, x1:x1 + w1] = img1

    imgs = [(img1, x1, y1), (img2, x2, y2), (img3, x3, y3), (img4, x4, y4)]
    for _ in range(3):
        rnd.shuffle(imgs)
        fix_overlaps(res, imgs)

    cv2.imshow('frame', res)
    cv2.waitKey(0)
    cv2.destroyAllWindows()