refactor(renderer): remove viewport rendering and simplify virtualization

Author: sudo-tee

lua/opencode/config.lua

@@ -151,10 +151,6 @@ M.defaults = {
         show_reasoning_output = true,
       },
       always_scroll_to_bottom = false,
-      viewport = {
-        enabled = true,
-        overscan = 8,
-      },
     },
     questions = {
       use_vim_ui_select = false, -- If true, render questions with vim.ui.select instead of in the output buffer

lua/opencode/ui/renderer.lua

@@ -52,41 +52,8 @@ local function normalize_session_messages(session_data)
   return messages
 end
 
-local function restore_output_view(visible_render, restore_state)
-  local windows = state.windows
-  local output_win = windows and windows.output_win
-  if not restore_state or not output_win or not vim.api.nvim_win_is_valid(output_win) then
-    return false
-  end
-
-  local visible_line_count = visible_render.visible_line_count or 0
-  if visible_line_count <= 0 then
-    return false
-  end
-
-  local relative_topline = restore_state.absolute_scroll_top - (visible_render.start_line_offset or 0) + 1
-  relative_topline = math.max(relative_topline, 1)
-  relative_topline = math.min(relative_topline, visible_line_count)
-
-  local cursor_delta = math.max((restore_state.view.lnum or 1) - (restore_state.view.topline or 1), 0)
-  local relative_cursor = math.min(relative_topline + cursor_delta, visible_line_count)
-  relative_cursor = math.max(relative_cursor, relative_topline)
-
-  local view = vim.deepcopy(restore_state.view)
-  view.topline = relative_topline
-  view.lnum = relative_cursor
-  view.col = math.max(view.col or 0, 0)
-  view.leftcol = 0
-
-    return pcall(with_suppressed_scroll_tracking, function()
-    vim.api.nvim_win_call(output_win, function()
-      vim.fn.winrestview(view)
-    end)
-  end)
-end
-
 ---@param render_plan { strategy: 'noop'|'full'|'patch', visible_render: table, patch?: table }
-local function apply_render_plan(render_plan, should_scroll, restore_state)
+local function apply_render_plan(render_plan, should_scroll)
   if not render_plan or render_plan.strategy == 'noop' then
     return false
   end
@@ -98,18 +65,6 @@ local function apply_render_plan(render_plan, should_scroll, restore_state)
   end)
 
   ctx.prev_visible_render = visible_render
-  ctx.current_visible_render = {
-    start_line_offset = visible_render.start_line_offset or 0,
-    total_line_count = visible_render.total_line_count or 0,
-    visible_line_count = visible_render.visible_line_count or 0,
-    start_index = visible_render.start_index or 1,
-    end_index = visible_render.end_index or #visible_render.blocks,
-  }
-
-  if restore_output_view(visible_render, restore_state) then
-    trigger_on_data_rendered()
-    return true
-  end
 
   if should_scroll then
     M.scroll_to_bottom()
@@ -120,47 +75,6 @@ local function apply_render_plan(render_plan, should_scroll, restore_state)
   return true
 end
 
-function M.get_viewport_render_request()
-  local viewport_config = config.ui.output.viewport or {}
-  if viewport_config.enabled == false or output_window.is_at_bottom() then
-    return nil
-  end
-
-  local windows = state.windows
-  local output_win = windows and windows.output_win
-  if not output_win or not vim.api.nvim_win_is_valid(output_win) then
-    return nil
-  end
-
-  local visible_render = ctx.current_visible_render
-  if not visible_render then
-    return nil
-  end
-
-  local ok, view = pcall(vim.api.nvim_win_call, output_win, vim.fn.winsaveview)
-  if not ok or type(view) ~= 'table' then
-    return nil
-  end
-
-  local win_height = vim.api.nvim_win_get_height(output_win)
-  if win_height <= 0 then
-    return nil
-  end
-
-  local scroll_top = visible_render.start_line_offset + math.max((view.topline or 1) - 1, 0)
-  local overscan = viewport_config.overscan
-  if overscan == nil then
-    overscan = math.max(win_height, 8)
-  end
-
-  return {
-    scroll_top = scroll_top,
-    win_height = win_height,
-    overscan = math.max(math.floor(overscan), 0),
-    view = view,
-  }
-end
-
 -- Expose event handlers on M so tests can call them directly and subscriptions
 -- can be stubbed cleanly (e.g. stub(renderer, '_render_full_session_data'))
 M.on_session_updated = events.on_session_updated
@@ -315,7 +229,7 @@ function M._render_full_session_data(session_data)
   local set_mode_from_messages = not state.current_model
 
   update_current_message_state(state.messages)
-  local plan = planner.plan_update(nil, ctx.prev_visible_render, state.messages, M.get_viewport_render_request())
+  local plan = planner.plan_update(nil, ctx.prev_visible_render, state.messages)
   apply_render_plan(plan, true)
 
   if set_mode_from_messages then
@@ -334,14 +248,9 @@ function M.perform_scheduled_render(snapshot)
   end
 
   local should_scroll = snapshot == nil or snapshot.full_render == true or output_window.is_at_bottom()
-  local viewport_request = M.get_viewport_render_request()
-  local restore_state = viewport_request and {
-    absolute_scroll_top = viewport_request.scroll_top,
-    view = viewport_request.view,
-  } or nil
   update_current_message_state(state.messages)
-  local plan = planner.plan_update(snapshot, ctx.prev_visible_render, state.messages, viewport_request)
-  if not apply_render_plan(plan, should_scroll, restore_state) then
+  local plan = planner.plan_update(snapshot, ctx.prev_visible_render, state.messages)
+  if not apply_render_plan(plan, should_scroll) then
     return
   end
   ctx.last_rendered_session_id = state.active_session.id

lua/opencode/ui/renderer/ctx.lua

@@ -10,8 +10,6 @@ local ctx = {
   prev_line_count = 0,
   ---@type { blocks?: RenderBlock[] }|nil
   prev_visible_render = nil,
-  ---@type { start_line_offset: integer, total_line_count: integer, visible_line_count: integer, start_index: integer, end_index: integer }|nil
-  current_visible_render = nil,
   ---@type string|nil
   last_rendered_session_id = nil,
   ---@type table<string, boolean>
@@ -30,7 +28,6 @@ function ctx:reset()
   self.render_state:reset()
   self.prev_line_count = 0
   self.prev_visible_render = nil
-  self.current_visible_render = nil
   self.last_rendered_session_id = nil
   self.dirty_messages = {}
   self.dirty_parts = {}

lua/opencode/ui/renderer/planner.lua

@@ -7,6 +7,23 @@ local virtualize = require('opencode.ui.renderer.virtualize')
 
 local M = {}
 
+local function is_idle_render()
+  return state.jobs.is_running() == false
+end
+
+local function get_effective_max_messages()
+  if not is_idle_render() then
+    return nil
+  end
+
+  local max_messages = config.ui.output.max_rendered_messages
+  if type(max_messages) ~= 'number' or max_messages <= 0 then
+    return nil
+  end
+
+  return max_messages
+end
+
 local function same_block_output(left, right)
   if left == right then
     return true
@@ -81,23 +98,20 @@ local function same_visible_render(left, right)
     end
   end
 
-  return (left and left.start_line_offset or 0) == (right and right.start_line_offset or 0)
-    and (left and left.total_line_count or 0) == (right and right.total_line_count or 0)
+  return (left and left.total_line_count or 0) == (right and right.total_line_count or 0)
     and (left and left.visible_line_count or 0) == (right and right.visible_line_count or 0)
     and (left and left.start_index or 1) == (right and right.start_index or 1)
     and (left and left.end_index or #left_blocks) == (right and right.end_index or #right_blocks)
     and (left and left.hidden_message_count or 0) == (right and right.hidden_message_count or 0)
 end
 
 local function get_visible_message_id_set_for_tail(messages)
-  local max_messages = config.ui.output.max_rendered_messages
-  if type(max_messages) ~= 'number' or max_messages <= 0 then
+  local max_messages = get_effective_max_messages()
+  if max_messages == nil then
     return nil
   end
 
-  if config.ui.output.max_rendered_lines ~= nil then
-    return nil
-  end
+  -- no-op: max_rendered_lines support removed
 
   local visible_ids = {}
   local visible_count = math.min(max_messages, #(messages or {}))
@@ -114,12 +128,12 @@ local function get_visible_message_id_set_for_tail(messages)
   return visible_ids
 end
 
-local function snapshot_affects_visible_tail(snapshot, messages, viewport_request)
+local function snapshot_affects_visible_tail(snapshot, messages)
   if not snapshot then
     return true
   end
 
-  if snapshot.full_render == true or viewport_request ~= nil then
+  if snapshot.full_render == true then
     return true
   end
 
@@ -167,24 +181,18 @@ local function find_revert_index(messages)
 end
 
 ---@param messages OpencodeMessage[]
----@param viewport_request? { scroll_top?: integer, win_height?: integer, overscan?: integer, view?: table }
 ---@return {
 ---  blocks: RenderBlock[],
 ---  start_index: integer,
 ---  end_index: integer,
----  start_line_offset: integer,
 ---  hidden_block_count: integer,
----  leading_hidden_block_count: integer,
----  trailing_hidden_block_count: integer,
 ---  hidden_message_count: integer,
----  leading_hidden_message_count: integer,
----  trailing_hidden_message_count: integer,
 ---  total_line_count: integer,
 ---  visible_line_count: integer
 ---}
-function M.plan_visible_render(messages, viewport_request)
+function M.plan_visible_render(messages)
   local revert_index = find_revert_index(messages)
-  local max_messages = config.ui.output.max_rendered_messages
+  local max_messages = get_effective_max_messages()
 
   local visible_messages = messages
   if revert_index then
@@ -200,7 +208,7 @@ function M.plan_visible_render(messages, viewport_request)
   end
 
   local base_blocks = session_view.build_blocks(visible_messages, {
-    max_messages = viewport_request and nil or max_messages,
+    max_messages = max_messages,
     get_child_parts = function(session_id)
       return ctx.render_state:get_child_session_parts(session_id)
     end,
@@ -211,11 +219,10 @@ function M.plan_visible_render(messages, viewport_request)
   })
 
   local visible_render = virtualize.select_visible_blocks(base_blocks, {
-    max_lines = viewport_request and nil or config.ui.output.max_rendered_lines,
-    viewport = viewport_request,
+    max_messages = max_messages,
   })
 
-  if not viewport_request and tail_hidden_message_count > 0 then
+  if tail_hidden_message_count > 0 then
     local hidden_block = overlays.render_hidden_history({
       hidden_count = tail_hidden_message_count,
     })
@@ -225,9 +232,7 @@ function M.plan_visible_render(messages, viewport_request)
     end
   end
 
-  if not viewport_request then
-    visible_render.hidden_message_count = tail_hidden_message_count
-  end
+  visible_render.hidden_message_count = tail_hidden_message_count
 
   return visible_render
 end
@@ -282,17 +287,16 @@ end
 ---@param snapshot? { full_render?: boolean, dirty_messages?: table<string, boolean>, dirty_parts?: table<string, boolean> }
 ---@param prev_visible_render? { blocks?: RenderBlock[] }
 ---@param messages OpencodeMessage[]
----@param viewport_request? { scroll_top?: integer, win_height?: integer, overscan?: integer, view?: table }
 ---@return { strategy: 'noop'|'full'|'patch', visible_render: table, patch?: table }
-function M.plan_update(snapshot, prev_visible_render, messages, viewport_request)
-  if snapshot_affects_visible_tail(snapshot, messages, viewport_request) == false then
+function M.plan_update(snapshot, prev_visible_render, messages)
+  if snapshot_affects_visible_tail(snapshot, messages) == false then
     return {
       strategy = 'noop',
       visible_render = prev_visible_render or { blocks = {} },
     }
   end
 
-  local next_visible_render = M.plan_visible_render(messages, viewport_request)
+  local next_visible_render = M.plan_visible_render(messages)
   return M.plan_apply(prev_visible_render, next_visible_render)
 end