venn.nvim

Draw ASCII diagrams in Neovim.

Installation

Install using your prefered method:

• vim-plug.

Plug 'jbyuki/venn.nvim'

• packer.nvim

use "jbyuki/venn.nvim"

Usage

• set virtualedit=all or set ve=all. This will allow you to freely move the cursor in the buffer. (see help virtualedit).

• Enter in Visual Block mode using <C-v> or <C-q>. Select the region where the box should be.

• Invoke :VBox. This will draw a rectangle. In case, it has a width or a height of 1, it will draw a line.

Key Mapping

Using hydra.nvim

Any modal keymapping system would work to get additional keys usable for drawing and moving selections, since there are many options to draw and move around pieces.

Draw diagrams

A relative complete configuration to draw diagrams with boxes, lines and arrows in utf can be found in the hydra wiki and the more extensive version including explanations in this repo wiki.

Moving selection

Drawing and text repositioning is a frequent operation on more complex graphics. While gR allows to overwrite text from left to right, it does not allow to move (text) selections around. Using mini.move works with for now main usability restriction of no correct fixup after collisions and an example configuration can be found in the hydra wiki and the more extensive version including explanations in this repo wiki.

Using toggle command

You can map :VBox commands to allow different ways of drawing lines.

Use the following function in your neovim config to toggle drawing lines on HJKL directional keys to allow for faster creation of diagrams:

-- venn.nvim: enable or disable keymappings
function _G.Toggle_venn()
    local venn_enabled = vim.inspect(vim.b.venn_enabled)
    if venn_enabled == "nil" then
        vim.b.venn_enabled = true
        vim.cmd[[setlocal ve=all]]
        -- draw a line on HJKL keystokes
        vim.api.nvim_buf_set_keymap(0, "n", "J", "<C-v>j:VBox<CR>", {noremap = true})
        vim.api.nvim_buf_set_keymap(0, "n", "K", "<C-v>k:VBox<CR>", {noremap = true})
        vim.api.nvim_buf_set_keymap(0, "n", "L", "<C-v>l:VBox<CR>", {noremap = true})
        vim.api.nvim_buf_set_keymap(0, "n", "H", "<C-v>h:VBox<CR>", {noremap = true})
        -- draw a box by pressing "f" with visual selection
        vim.api.nvim_buf_set_keymap(0, "v", "f", ":VBox<CR>", {noremap = true})
    else
        vim.cmd[[setlocal ve=]]
        vim.api.nvim_buf_del_keymap(0, "n", "J")
        vim.api.nvim_buf_del_keymap(0, "n", "K")
        vim.api.nvim_buf_del_keymap(0, "n", "L")
        vim.api.nvim_buf_del_keymap(0, "n", "H")
        vim.api.nvim_buf_del_keymap(0, "v", "f")
        vim.b.venn_enabled = nil
    end
end
-- toggle keymappings for venn using <leader>v
vim.api.nvim_set_keymap('n', '<leader>v', ":lua Toggle_venn()<CR>", { noremap = true})