This is the code snippet that creates that slider:

Code:
						dmap_slider = Slider(
							colSpan = 2, fitParent = true, 
							disabled = !sm_dmap(local_dmap.type),
							offset = local_dmap.xoff,
							maxheight = 16_px,
							minOffset = -7, maxOffset = 15,
							onValChangedFunc = [&](int32_t offset)
							{
								local_dmap.xoff = offset;
								dmap_mmap->setOffset(offset);
							}),
which is declared in edit_dmap.h:

Code:
	std::shared_ptr<GUI::Slider> dmap_slider;