if(panel1.pos_x+panel1.size_x >= panel2.pos_x &&
panel1.pos_y+panel1.size_y >= panel2.pos_y &&
panel1.pos_x <= panel2.pos_x+panel2.size_x &&
panel1.pos_y <= panel2.pos_y+panel2.size_y) {
panel1 touches panel2
}

Should work, but untested. If you don't understand something, think a second about it (or 2), use the manual then feel free to ask.
Have you done the tutorial(s)?

"Falls das Resultat nicht einfach nur dermassen gut aussieht, sollten Sie nochmal von vorn anfangen..." - Manual

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