feat: add percent-based current-line positioning

Adds a new option to place the current line based on its progress through
the file, instead of keeping it fixed at the viewport middle.

Config:
- `current_line_position = "percent"`  (new)
- `current_line_position = "center"`   (default/unchanged)

Author: Isrothy

README.md

@@ -225,6 +225,14 @@ vim.g.neominimap = {
   -- How many rows a dot should span
   y_multiplier = 1, ---@type integer
 
+  ---@alias Neominimap.Config.CurrentLinePosition "center" | "percent"
+
+  -- How the minimap places the current line vertically.
+  -- `"center"`  -> pins the line to the viewport middle (window-relative).
+  -- `"percent"` -> maps line index / total lines to minimap height (file-relative).
+  -- Note: here "center" means the middle of the **minimap window**, not "center of the file".
+  current_line_position = "center", ---@type Neominimap.Config.CurrentLinePosition
+
   buffer = {
     -- When true, the minimap will be recreated when you delete the buffer.
     -- When false, the minimap will be disabled for the current buffer when you delete the minimap buffer.
@@ -405,7 +413,7 @@ vim.g.neominimap = {
   signcolumn = "auto",
   number = false,
   relativenumber = false,
-  scrolloff = 99999, -- To center minimap
+  scrolloff = config.current_line_position == "center" and 99999 or 0,
   sidescrolloff = 0,
   winblend = 0,
   cursorline = true,

lua/neominimap/config/internal.lua

@@ -53,6 +53,14 @@ local M = {
     -- How many rows a dot should span
     y_multiplier = 1, ---@type integer
 
+    ---@alias Neominimap.Config.CurrentLinePosition "center" | "percent"
+
+    --- How the minimap places the current line vertically.
+    --- `"center"`  -> pins the line to the viewport middle (window-relative).
+    --- `"percent"` -> maps line index / total lines to minimap height (file-relative).
+    --- Note: here "center" means the middle of the **minimap window**, not "center of the file".
+    current_line_position = "center", ---@type Neominimap.Config.CurrentLinePosition
+
     buffer = {
         -- When true, the minimap will be recreated when you delete the buffer.
         -- When false, the minimap will be disabled for the current buffer when you delete the minimap buffer.

lua/neominimap/config/meta.lua

@@ -13,6 +13,7 @@ local M = {}
 ---@field x_multiplier? integer
 ---@field y_multiplier? integer
 ---@field sync_cursor? boolean
+---@field current_line_position?  Neominimap.Config.CurrentLinePosition
 ---@field buffer? Neominimap.BufferConfig
 ---@field layout? Neominimap.Config.LayoutType
 ---@field float? Neominimap.FloatConfig

lua/neominimap/config/validator.lua

@@ -93,6 +93,7 @@ M.validate_config = function(cfg)
         tab_filter = { cfg.tab_filter, "function" },
         x_multiplier = { cfg.x_multiplier, "number" },
         y_multiplier = { cfg.y_multiplier, "number" },
+        current_line_position = { cfg.current_line_position, "string" },
         sync_cursor = { cfg.sync_cursor, "boolean" },
         delay = { cfg.delay, "number" },
 

lua/neominimap/window/util.lua

@@ -60,7 +60,7 @@ local default_winopt = {
     signcolumn = "auto",
     number = false,
     relativenumber = false,
-    scrolloff = 99999, -- To center minimap
+    scrolloff = config.current_line_position == "center" and 99999 or 0,
     sidescrolloff = 0,
     winblend = 0,
     cursorline = true,
@@ -79,6 +79,23 @@ M.set_winopt = function(opt, winid)
     config.winopt(opt, winid)
 end
 
+---@param winid integer
+---@param row integer
+local function set_current_line_by_percentage(winid, row)
+    local win_h = M.win_get_true_height(winid)
+    local bufnr = api.nvim_win_get_buf(winid)
+    local line_cnt = api.nvim_buf_line_count(bufnr)
+    local topline = math.floor(row - (row * win_h) / line_cnt)
+    row = math.max(1, math.min(row, line_cnt))
+    topline = math.max(1, math.min(topline, line_cnt))
+    return function()
+        local view = vim.fn.winsaveview()
+        view.topline = topline
+        view.lnum = row - 1
+        vim.fn.winrestview(view)
+    end
+end
+
 ---@param swinid integer
 ---@param mwinid integer
 M.sync_to_minimap = function(swinid, mwinid)
@@ -139,7 +156,13 @@ M.sync_to_source = function(swinid, mwinid)
     if row <= line_cnt then
         local util = require("neominimap.util")
         vim.schedule(function()
-            local ok = util.noautocmd(pcall)(vim.api.nvim_win_set_cursor, mwinid, { row, 0 })
+            local ok = util.noautocmd(pcall)((function()
+                if config.current_line_position == "center" then
+                    return vim.api.nvim_win_set_cursor, mwinid, { row, 0 }
+                else
+                    return api.nvim_win_call, mwinid, set_current_line_by_percentage(mwinid, row)
+                end
+            end)())
             if not ok then
                 logger.log.error("Failed to set cursor")
             end