Can I generate big unique terrain texture by parts with photoshop ai?

Photoshop is not designed for this task, which requires multiple maps for each tile. You might want to take a look at World Creator, which is designed for such work.

Dave

@kirkr5689 While Photoshop AI is powerful, it cannot inherently solve the most complex technical aspects of creating a true large-scale map. Photoshop is primarily a 2D image editing program, and while it has some 3D capabilities, it doesn't generate high-resolution, georeferenced, aerial-style terrain as a core function. To create a large-scale, high-resolution aerial or satellite-like map image from smaller parts with perfectly contiguous features (like roads and rivers), you'd typically need a dedicated 3D terrain generation software (like World Machine, Gaea, or Terragen) or a GIS application (like QGIS or ArcGIS) that can handle real-world scale and tiling (similar to a UDIM or a splat map used in game engines). Once these large textures are generated and stitched (often using a technique called tiling or mosaicking), you could then use Photoshop only for the final, detailed 2D editing and touch-ups on the resulting large image.