Add scroll

lua/custom/plugins/scroll.lua

@@ -0,0 +1,48 @@
+return {
+  'karb94/neoscroll.nvim',
+  config = function()
+    local neoscroll = require("neoscroll")
+
+    local easing = "sine"
+    local zz_time_ms = 100
+    local jump_time_ms = 200
+
+    local centering_function = function()
+      local defer_time_ms = 10
+      -- The `defer_fn` is a bit of a hack.
+      -- We use it so that `neoscroll.init.scroll` will be false when we call `neoscroll.zz`
+      -- As long as we don't input another neoscroll mapping in the timeout,
+      -- we should be able to center the cursor.
+      vim.defer_fn(function()
+        neoscroll.zz(zz_time_ms, easing)
+      end, defer_time_ms)
+    end
+
+    neoscroll.setup({
+      pre_hook = function()
+        vim.opt.eventignore:append({
+          'WinScrolled',
+          'CursorMoved',
+        })
+      end,
+      post_hook = function(info)
+        vim.opt.eventignore:remove({
+          'WinScrolled',
+          'CursorMoved',
+        })
+        if info ~= "center" then
+          return
+        end
+
+        centering_function()
+      end,
+    })
+
+    local mappings = {}
+
+    mappings["<C-u>"] = { "scroll", { "-vim.wo.scroll", "true", jump_time_ms, easing, "'center'" } }
+    mappings["<C-d>"] = { "scroll", { "vim.wo.scroll", "true", jump_time_ms, easing, "'center'" } }
+
+    require("neoscroll.config").set_mappings(mappings)
+  end,
+}