Wire up kitty tmux workaround to terminal query result.

When we see tmux, we need to do things differently, so let's
bubble that up from when we query the terminal anyway.

Issues: #95

Author: hzeller

src/kitty-canvas.cc

@@ -71,8 +71,12 @@ static char *AppendEscaped(char *pos, char c, bool wrap_tmux) {
 
 KittyGraphicsCanvas::KittyGraphicsCanvas(BufferedWriteSequencer *ws,
                                          ThreadPool *thread_pool,
+                                         bool tmux_workaround_needed,
                                          const DisplayOptions &opts)
-    : TerminalCanvas(ws), options_(opts), executor_(thread_pool) {}
+    : TerminalCanvas(ws),
+      options_(opts),
+      tmux_workaround_needed_(tmux_workaround_needed),
+      executor_(thread_pool) {}
 
 void KittyGraphicsCanvas::Send(int x, int dy, const Framebuffer &fb_orig,
                                SeqType seq_type, Duration end_of_frame) {
@@ -123,7 +127,7 @@ void KittyGraphicsCanvas::Send(int x, int dy, const Framebuffer &fb_orig,
     const int cols   = fb->width() / opts.cell_x_px;
     const int rows   = -cell_height_for_pixels(-fb->height());
     const int indent = x / opts.cell_x_px;
-    bool wrap_tmux   = false;
+    bool wrap_tmux   = tmux_workaround_needed_;
     std::function<OutBuffer()> encode_fun = [opts, fb, id, buffer, offset, rows,
                                              cols, indent, wrap_tmux]() {
         std::unique_ptr<const Framebuffer> auto_delete(fb);

src/kitty-canvas.h

@@ -25,6 +25,7 @@ namespace timg {
 class KittyGraphicsCanvas final : public TerminalCanvas {
 public:
     KittyGraphicsCanvas(BufferedWriteSequencer *ws, ThreadPool *thread_pool,
+                        bool tmux_workaround_needed,
                         const DisplayOptions &opts);
 
     int cell_height_for_pixels(int pixels) const final;
@@ -34,6 +35,7 @@ class KittyGraphicsCanvas final : public TerminalCanvas {
 
 private:
     const DisplayOptions &options_;
+    const bool tmux_workaround_needed_;
     ThreadPool *const executor_;
 
     char *RequestBuffer(int width, int height);

src/term-query.cc

@@ -186,6 +186,7 @@ TermGraphicsInfo QuerySupportedGraphicsProtocol() {
     TermGraphicsInfo result;
     result.preferred_graphics                  = GraphicsProtocol::kNone;
     result.known_broken_sixel_cursor_placement = false;
+    result.in_tmux                             = false;
 
     const char *const term = getenv("TERM");
     if (term && strcmp(term, "xterm-kitty") == 0) {
@@ -229,6 +230,9 @@ TermGraphicsInfo QuerySupportedGraphicsProtocol() {
                           result.preferred_graphics = GraphicsProtocol::kSixel;
                           result.known_broken_sixel_cursor_placement = true;
                       }
+                      if (contains(data, len, "tmux")) {
+                          result.in_tmux = true;
+                      }
                       // We finish once we found the response to DSR5
                       return (const char *)memmem(data, len, "\033[0n", 3);
                   });

src/term-query.h

@@ -30,6 +30,7 @@ enum class GraphicsProtocol {
 struct TermGraphicsInfo {
     GraphicsProtocol preferred_graphics;
     bool known_broken_sixel_cursor_placement;
+    bool in_tmux;
 };
 
 // Query the terminal if and what graphics protocol it supports.

src/timg.cc

@@ -123,6 +123,7 @@ struct PresentationOptions {
     // Rendering
     Pixelation pixelation         = Pixelation::kNotChosen;
     bool sixel_cursor_workaround  = false;
+    bool tmux_workaround          = false;
     bool terminal_use_upper_block = false;
     bool use_256_color = false;  // For terminals that don't do 24 bit color
 
@@ -306,6 +307,7 @@ static void PresentImages(LoadedImageSources *loaded_sources,
     case Pixelation::kKittyGraphics:
         compression_pool.reset(new ThreadPool(sequencer->max_queue_len() + 1));
         canvas.reset(new KittyGraphicsCanvas(sequencer, compression_pool.get(),
+                                             present.tmux_workaround,
                                              display_opts));
         break;
     case Pixelation::kiTerm2Graphics:
@@ -728,7 +730,8 @@ int main(int argc, char *argv[]) {
         present.pixelation = Pixelation::kQuarterBlock;  // Good default.
 #ifdef WITH_TIMG_TERMINAL_QUERY
         if (term.font_width_px > 0 && term.font_height_px > 0) {
-            auto graphics_info = timg::QuerySupportedGraphicsProtocol();
+            auto graphics_info      = timg::QuerySupportedGraphicsProtocol();
+            present.tmux_workaround = graphics_info.in_tmux;
             switch (graphics_info.preferred_graphics) {
             case timg::GraphicsProtocol::kIterm2:
                 present.pixelation = Pixelation::kiTerm2Graphics;
@@ -750,6 +753,11 @@ int main(int argc, char *argv[]) {
         }
 #endif
     }
+    else if (present.pixelation == Pixelation::kKittyGraphics) {
+        // If the user manually chooses kitty, we still need to know if in tmux
+        auto graphics_info      = timg::QuerySupportedGraphicsProtocol();
+        present.tmux_workaround = graphics_info.in_tmux;
+    }
 #if defined(WITH_TIMG_SIXEL) && defined(WITH_TIMG_TERMINAL_QUERY)
     // If the user manually choose sixel, we still can't avoid a terminal
     // query, as we have to figure out if it has a broken cursor implementation.
@@ -760,6 +768,17 @@ int main(int argc, char *argv[]) {
     }
 #endif
 
+    // If we are in tmux and use the kitty protocol, we need to tell it to
+    // allow pass-through.
+    // Somewhat broken abstraction here, should move to some
+    // TerminalCanvas::Prepare().
+    if (present.pixelation == Pixelation::kKittyGraphics &&
+        present.tmux_workaround) {
+        if (system("tmux set -p allow-passthrough on") != 0) {
+            fprintf(stderr, "Could not set tmux passthrough for graphics\n");
+        }
+    }
+
     // If 'none' is chosen for background color, then using the
     // PNG compression with alpha channels gives us compositing on client side
     if (is_pixel_direct_p(present.pixelation) &&