feat(image): proper inline rendering of math expressions. Closes #1318. Closes #1454

lua/snacks/image/init.lua

@@ -6,10 +6,11 @@
 ---@field buf snacks.image.buf
 ---@field doc snacks.image.doc
 ---@field convert snacks.image.convert
+---@field inline snacks.image.inline
 local M = setmetatable({}, {
   ---@param M snacks.image
   __index = function(M, k)
-    if vim.tbl_contains({ "terminal", "image", "placement", "util", "doc", "buf", "convert" }, k) then
+    if vim.tbl_contains({ "terminal", "image", "placement", "util", "doc", "buf", "convert", "inline" }, k) then
       M[k] = require("snacks.image." .. k)
     end
     return rawget(M, k)
@@ -24,6 +25,7 @@ M.meta = {
 ---@alias snacks.image.Size {width: number, height: number}
 ---@alias snacks.image.Pos {[1]: number, [2]: number}
 ---@alias snacks.image.Loc snacks.image.Pos|snacks.image.Size|{zindex?: number}
+---@alias snacks.image.Type "image"|"math"|"chart"
 
 ---@class snacks.image.Env
 ---@field name string
@@ -78,7 +80,13 @@ local defaults = {
     max_width = 80,
     max_height = 40,
     -- Set to `true`, to conceal the image text when rendering inline.
-    conceal = false, -- (experimental)
+    -- (experimental)
+    ---@param lang string tree-sitter language
+    ---@param type snacks.image.Type image type
+    conceal = function(lang, type)
+      -- only conceal math expressions
+      return type == "math"
+    end,
   },
   img_dirs = { "img", "images", "assets", "static", "public", "media", "attachments" },
   -- window options applied to windows displaying image buffers
@@ -101,6 +109,13 @@ local defaults = {
     placement = false,
   },
   env = {},
+  -- icons used to show where an inline image is located that is
+  -- rendered below the text.
+  icons = {
+    math = "󰪚 ",
+    chart = "󰄧 ",
+    image = " ",
+  },
   ---@class snacks.image.convert.Config
   convert = {
     notify = true, -- show a notification on error
@@ -137,7 +152,7 @@ local defaults = {
       -- but you can add more packages here. Useful for markdown documents.
       packages = { "amsmath", "amssymb", "amsfonts", "amscd", "mathtools" },
       tpl = [[
-        \documentclass[preview,border=2pt,varwidth,12pt]{standalone}
+        \documentclass[preview,border=0pt,varwidth,12pt]{standalone}
         \usepackage{${packages}}
         \begin{document}
         ${header}
@@ -162,6 +177,7 @@ Snacks.config.style("snacks_image", {
 
 Snacks.util.set_hl({
   Spinner = "Special",
+  Anchor = "Special",
   Loading = "NonText",
   Math = { fg = Snacks.util.color({ "@markup.math.latex", "Special", "Normal" }) },
 }, { prefix = "SnacksImage", default = true })
@@ -169,6 +185,7 @@ Snacks.util.set_hl({
 ---@class snacks.image.Opts
 ---@field pos? snacks.image.Pos (row, col) (1,0)-indexed. defaults to the top-left corner
 ---@field range? Range4
+---@field conceal? boolean
 ---@field inline? boolean render the image inline in the buffer
 ---@field width? number
 ---@field min_width? number
@@ -178,6 +195,8 @@ Snacks.util.set_hl({
 ---@field max_height? number
 ---@field on_update? fun(placement: snacks.image.Placement)
 ---@field on_update_pre? fun(placement: snacks.image.Placement)
+---@field type? snacks.image.Type
+---@field auto_resize? boolean
 
 local did_setup = false
 
@@ -220,6 +239,22 @@ function M.setup(ev)
   did_setup = true
   local group = vim.api.nvim_create_augroup("snacks.image", { clear = true })
 
+  vim.api.nvim_create_autocmd({ "BufWipeout", "BufDelete" }, {
+    group = group,
+    callback = function(e)
+      vim.schedule(function()
+        Snacks.image.placement.clean(e.buf)
+      end)
+    end,
+  })
+  vim.api.nvim_create_autocmd({ "ExitPre" }, {
+    group = group,
+    once = true,
+    callback = function()
+      Snacks.image.placement.clean()
+    end,
+  })
+
   if M.config.formats and #M.config.formats > 0 then
     vim.api.nvim_create_autocmd("BufReadCmd", {
       pattern = "*." .. table.concat(M.config.formats, ",*."),