Python Qt6 : simple merge sprites images with unittest feature.

Today, I created one python tool script with the artificial intelligence to merge sprites images.

I used the artificial intelligence to add unittest to create default images with PIL to test the result.

You can select your folder , select the align of merge features or test with unittest button.

This is the result and works well:

import os
import unittest
from PIL import Image, ImageDraw, ImageFont, ImageQt
import shutil
from PyQt6.QtWidgets import QApplication, QMainWindow, QPushButton, QFileDialog, QLabel, QVBoxLayout, QWidget, QComboBox
from PyQt6.QtGui import QPixmap
from PyQt6.QtCore import Qt
import sys

def create_test_image(path, size, number):
    img = Image.new('RGBA', size, (255, 255, 255, 255))
    draw = ImageDraw.Draw(img)
    # Simplified to just draw the number with a basic color background
    draw.rectangle((0, 0, size[0], size[1]), fill=(0, 100 * number % 255, 0, 255))
    try:
        font = ImageFont.load_default()
    except:
        font = None
    draw.text((size[0]//2-5, size[1]//2-5), str(number), fill=(255, 255, 255, 255), font=font)
    img.save(path, 'PNG')

def merge_sprites(folder_path, output_horizontal, output_vertical):
    images = [Image.open(os.path.join(folder_path, f)) for f in os.listdir(folder_path) if f.endswith(('.png', '.jpg', '.jpeg'))]
    
    if not images:
        return None, None
    
    width, height = images[0].size
    
    # Horizontal merge
    total_width = width * len(images)
    horizontal_image = Image.new('RGBA', (total_width, height))
    for i, img in enumerate(images):
        horizontal_image.paste(img, (i * width, 0))
    horizontal_image.save(output_horizontal, 'PNG')
    
    # Vertical merge
    total_height = height * len(images)
    vertical_image = Image.new('RGBA', (width, total_height))
    for i, img in enumerate(images):
        vertical_image.paste(img, (0, i * height))
    vertical_image.save(output_vertical, 'PNG')
    
    return horizontal_image, vertical_image

class TestSpriteMerger(unittest.TestCase):
    def setUp(self):
        self.test_folder = 'test_images'
        self.size = (50, 20)
        os.makedirs(self.test_folder, exist_ok=True)
        for i in range(3):
            create_test_image(os.path.join(self.test_folder, f'test_{i+1}.png'), self.size, i+1)
    
    def test_merge_horizontal(self):
        output_h = 'test_merged_horizontal.png'
        output_v = 'test_merged_vertical.png'
        h_img, _ = merge_sprites(self.test_folder, output_h, output_v)
        
        self.assertIsNotNone(h_img, "Horizontal merge failed")
        self.assertEqual(h_img.size, (self.size[0] * 3, self.size[1]))
    
    def test_merge_vertical(self):
        output_h = 'test_merged_horizontal.png'
        output_v = 'test_merged_vertical.png'
        _, v_img = merge_sprites(self.test_folder, output_h, output_v)
        
        self.assertIsNotNone(v_img, "Vertical merge failed")
        self.assertEqual(v_img.size, (self.size[0], self.size[1] * 3))
    
    def tearDown(self):
        if os.path.exists(self.test_folder):
            shutil.rmtree(self.test_folder)
        for f in ['test_merged_horizontal.png', 'test_merged_vertical.png']:
            if os.path.exists(f):
                os.remove(f)

class SpriteMergerApp(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Sprite Merger")
        self.setGeometry(100, 100, 800, 600)
        
        self.folder_path = ""
        
        layout = QVBoxLayout()
        
        self.select_button = QPushButton("Select Folder")
        self.select_button.clicked.connect(self.select_folder)
        layout.addWidget(self.select_button)
        
        self.merge_type = QComboBox()
        self.merge_type.addItems(["Horizontal", "Vertical"])
        layout.addWidget(self.merge_type)
        
        self.process_button = QPushButton("Process Selected Folder")
        self.process_button.clicked.connect(self.process_folder)
        layout.addWidget(self.process_button)
        
        self.test_button = QPushButton("Run Unit Test")
        self.test_button.clicked.connect(self.run_unit_test)
        layout.addWidget(self.test_button)
        
        self.result_label = QLabel("No image processed")
        layout.addWidget(self.result_label)
        
        self.image_label = QLabel()
        layout.addWidget(self.image_label)
        
        container = QWidget()
        container.setLayout(layout)
        self.setCentralWidget(container)
    
    def select_folder(self):
        self.folder_path = QFileDialog.getExistingDirectory(self, "Select Sprite Folder")
        self.result_label.setText(f"Selected: {self.folder_path}")
    
    def process_folder(self):
        if not self.folder_path:
            self.result_label.setText("Please select a folder first")
            return
        h_img, v_img = merge_sprites(self.folder_path, 'merged_horizontal.png', 'merged_vertical.png')
        selected_type = self.merge_type.currentText()
        
        img = h_img if selected_type == "Horizontal" else v_img
        if img:
            pixmap = QPixmap.fromImage(ImageQt.ImageQt(img))
            self.image_label.setPixmap(pixmap.scaled(700, 500, aspectRatioMode=Qt.AspectRatioMode.KeepAspectRatio))
            self.result_label.setText(f"{selected_type} merge completed")
        else:
            self.result_label.setText(f"{selected_type} merge failed")
    
    def run_unit_test(self):
        suite = unittest.TestLoader().loadTestsFromTestCase(TestSpriteMerger)
        result = unittest.TextTestRunner().run(suite)
        
        test_folder = 'test_images'
        os.makedirs(test_folder, exist_ok=True)
        for i in range(3):
            create_test_image(os.path.join(test_folder, f'test_{i+1}.png'), (50, 20), i+1)
        
        h_img, v_img = merge_sprites(test_folder, 'test_merged_horizontal.png', 'test_merged_vertical.png')
        selected_type = self.merge_type.currentText()
        
        img = h_img if selected_type == "Horizontal" else v_img
        if img:
            pixmap = QPixmap.fromImage(ImageQt.ImageQt(img))
            self.image_label.setPixmap(pixmap.scaled(700, 500, aspectRatioMode=Qt.AspectRatioMode.KeepAspectRatio))
            self.result_label.setText(f"Unit tests: {result.testsRun} run, {len(result.failures)} failed, showing {selected_type.lower()} merge")
        else:
            self.result_label.setText(f"Unit tests: {result.testsRun} run, {len(result.failures)} failed, merge failed")

if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = SpriteMergerApp()
    window.show()
    sys.exit(app.exec())

Python Qt6 : Test application with unittest and QtTest.

In this simple example, I add a test class with unittest to sleep the application and QtTest to wait for the window to open after pressing the button.

To run the unittest you need to uncomment this row of source code:

#unittest.main()

Let's see the source code:

import sys

from PyQt6.QtWidgets import QApplication, QDialog, QMainWindow, QPushButton
from PyQt6 import QtCore, QtGui, QtWidgets
from PyQt6 import QtTest 

# Unitest area
import unittest
from time import sleep
def sleep_sec(sec):
    sleep(10*sec)
#
#define class for unittest
class Test(unittest.TestCase):
    def test_square(self):
        sleep_sec(5)

class Ui_Dialog(object):
    def setupUi(self, Dialog):
        Dialog.setObjectName("Dialog")
        Dialog.resize(640, 480)
        self.verticalLayout = QtWidgets.QVBoxLayout(Dialog)

    def retranslateUi(self, Dialog):
        _translate = QtCore.QCoreApplication.translate

class Window(QMainWindow):
    """Main window."""
    def __init__(self, parent=None):
        """Initializer."""
        super().__init__(parent)
        # Use a QPushButton for the central widget
        self.centralWidget = QPushButton("Test_Button")

        # Connect the .clicked() signal with the .onTest_BtnClicked() slot
        self.centralWidget.clicked.connect(self.onTest_BtnClicked)
        self.setCentralWidget(self.centralWidget)

    # Create a slot for launching the Test_ dialog
    def onTest_BtnClicked(self):
        """Launch the Test_ dialog."""
        dlg = Test_Dlg(self)
        # This will test with QtTest just for click 
        QtTest.QTest.qWait(2500)

        dlg.exec()

class Test_Dlg(QDialog):
    """Test dialog."""
    def __init__(self, parent=None):
        super().__init__(parent)
        # Create an instance of the GUI
        self.ui = Ui_Dialog()
        # Run the .setupUi() method to show the GUI
        self.ui.setupUi(self)

if __name__ == "__main__":
    # this test all run of application and show :
    # Ran 1 test in 50.001s
    # uncoment this
    #unittest.main()
    
    # Create the application
    app = QApplication(sys.argv)
    # Create and show the application's main window
    win = Window()
    win.show()
    # Run the application's main loop
    sys.exit(app.exec())