This is an OpenSCAD tool to create custom surface textures with a lot of hearts . Using the STLs this produces is easy enough - load your model into your slicer, and then load as a modifier one of the premade modifiers that's large enough for the model (the modifier can be bigger than the model!).

Make sure the modifier is aligned to the bed (in BambuStudio, it's the default AFAIK) or the top surface, and then change some of its parameters. You can try setting the top/bottom infill pattern to octagram spiral, concentric, or just change the infill angle. Shiny, glittery filaments work best for top patterns, and shiny surfaces work best for base patterns —but you can use a textured build plate, too!

If you have a multi-material unit, such as Bambulabs AMS, Prusa's MMU, Mosaic Palette & so on, you can use the same pattern as both negative modifier (to remove the hearts from the model) and then add it as a part, in a different color. Or, just add it as a part on top of your flat-top model, and have a nice array of hearts on it.

But you don't have to limit yourself to the premade mods! The OpenSCAD file is very powerful. Some of its features:

• Allows partial selection of the pattern, so you can combine several pieces into one. (F.i., you can have even columns with the hearts upright, and odd columns with the hearts upside-down).
• 4 different modes of alternation/displacement of columns and rows.
• 3D or 2D export for SVG/DXF and use in CNC machines.
• Different shapes (and orientation) for the pattern to fill: squares, rectangles, polygons, circles…
• Determine the spacing of the hearts and the padding of the area.
• Outlining hearts (in 2 different ways) instead of just solid ones.
• Produce negative or positive outputs (for negative modifiers/volumes or mesh modifiers)
• Choose between 4 orientations of the hearts
• 10 different selection modes.
• Non-printable centering fillet for easy alignment of the parts.

If you're new to OpenSCAD, check the enclosed PDF “Using OpenSCAD customizer”, that will walk you through the use of a customizer-enabled OpenSCAD file.