Merge branch 'ime' of https://github.com/page-down/kitty

docs/changelog.rst

@@ -46,7 +46,7 @@ Detailed list of changes
 
 - When changing the cursor color via escape codes or remote control to a fixed color, do not reset cursor_text_color (:iss:`5994`)
 
-- Input Method Extensions: Fix incorrect rendering of IME in-progress text in some situations (:pull:`6002`)
+- Input Method Extensions: Fix incorrect rendering of IME in-progress and commited text in some situations (:pull:`6049`)
 
 - Linux: Reduce minimum required OpenGL version from 3.3 to 3.1 + extensions (:iss:`2790`)
 

glfw/cocoa_window.m

@@ -1454,15 +1454,11 @@ is_ascii_control_char(char x) {
 }
 
 void _glfwPlatformUpdateIMEState(_GLFWwindow *w, const GLFWIMEUpdateEvent *ev) {
-    [w->ns.view updateIMEStateFor: ev->type focused:(bool)ev->focused left:(CGFloat)ev->cursor.left top:(CGFloat)ev->cursor.top cellWidth:(CGFloat)ev->cursor.width cellHeight:(CGFloat)ev->cursor.height];
+    [w->ns.view updateIMEStateFor: ev->type focused:(bool)ev->focused];
 }
 
 - (void)updateIMEStateFor:(GLFWIMEUpdateType)which
                   focused:(bool)focused
-                     left:(CGFloat)left
-                      top:(CGFloat)top
-                cellWidth:(CGFloat)cellWidth
-               cellHeight:(CGFloat)cellHeight
 {
     if (which == GLFW_IME_UPDATE_FOCUS && !focused && [self hasMarkedText] && window) {
         [input_context discardMarkedText];
@@ -1472,16 +1468,7 @@ void _glfwPlatformUpdateIMEState(_GLFWwindow *w, const GLFWIMEUpdateEvent *ev) {
         _glfw.ns.text[0] = 0;
     }
     if (which != GLFW_IME_UPDATE_CURSOR_POSITION) return;
-    left /= window->ns.xscale;
-    top /= window->ns.yscale;
-    cellWidth /= window->ns.xscale;
-    cellHeight /= window->ns.yscale;
-    debug_key("updateIMEPosition: left=%f, top=%f, width=%f, height=%f\n", left, top, cellWidth, cellHeight);
-    const NSRect frame = [window->ns.view frame];
-    const NSRect rectInView = NSMakeRect(left,
-                                         frame.size.height - top - cellHeight,
-                                         cellWidth, cellHeight);
-    markedRect = [window->ns.object convertRectToScreen: rectInView];
+
     if (_glfwPlatformWindowFocused(window)) [[window->ns.view inputContext] invalidateCharacterCoordinates];
 }
 
@@ -1507,6 +1494,21 @@ void _glfwPlatformUpdateIMEState(_GLFWwindow *w, const GLFWIMEUpdateEvent *ev) {
                          actualRange:(NSRangePointer)actualRange
 {
     (void)range; (void)actualRange;
+    if (_glfw.callbacks.get_ime_cursor_position) {
+        GLFWIMEUpdateEvent ev = { .type = GLFW_IME_UPDATE_CURSOR_POSITION };
+        if (_glfw.callbacks.get_ime_cursor_position((GLFWwindow*)window, &ev)) {
+            const CGFloat left = (CGFloat)ev.cursor.left / window->ns.xscale;
+            const CGFloat top = (CGFloat)ev.cursor.top / window->ns.yscale;
+            const CGFloat cellWidth = (CGFloat)ev.cursor.width / window->ns.xscale;
+            const CGFloat cellHeight = (CGFloat)ev.cursor.height / window->ns.yscale;
+            debug_key("updateIMEPosition: left=%f, top=%f, width=%f, height=%f\n", left, top, cellWidth, cellHeight);
+            const NSRect frame = [window->ns.view frame];
+            const NSRect rectInView = NSMakeRect(left,
+                                                 frame.size.height - top - cellHeight,
+                                                 cellWidth, cellHeight);
+            markedRect = [window->ns.object convertRectToScreen: rectInView];
+        }
+    }
     return markedRect;
 }
 

glfw/glfw3.h

@@ -1732,6 +1732,7 @@ typedef enum {
 } GLFWClipboardType;
 typedef GLFWDataChunk (* GLFWclipboarditerfun)(const char *mime_type, void *iter, GLFWClipboardType ctype);
 typedef bool (* GLFWclipboardwritedatafun)(void *object, const char *data, size_t sz);
+typedef bool (* GLFWimecursorpositionfun)(GLFWwindow *window, GLFWIMEUpdateEvent *ev);
 
 /*! @brief Video mode type.
  *
@@ -1891,6 +1892,7 @@ GLFWAPI void glfwRemoveTimer(unsigned long long);
 GLFWAPI GLFWdrawtextfun glfwSetDrawTextFunction(GLFWdrawtextfun function);
 GLFWAPI GLFWcurrentselectionfun glfwSetCurrentSelectionCallback(GLFWcurrentselectionfun callback);
 GLFWAPI GLFWhascurrentselectionfun glfwSetHasCurrentSelectionCallback(GLFWhascurrentselectionfun callback);
+GLFWAPI GLFWimecursorpositionfun glfwSetIMECursorPositionCallback(GLFWimecursorpositionfun callback);
 
 /*! @brief Terminates the GLFW library.
  *

glfw/init.c

@@ -402,3 +402,10 @@ GLFWAPI GLFWhascurrentselectionfun glfwSetHasCurrentSelectionCallback(GLFWhascur
     _GLFW_SWAP_POINTERS(_glfw.callbacks.has_current_selection, cbfun);
     return cbfun;
 }
+
+GLFWAPI GLFWimecursorpositionfun glfwSetIMECursorPositionCallback(GLFWimecursorpositionfun cbfun)
+{
+    _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
+    _GLFW_SWAP_POINTERS(_glfw.callbacks.get_ime_cursor_position, cbfun);
+    return cbfun;
+}

glfw/internal.h

@@ -635,6 +635,7 @@ struct _GLFWlibrary
         GLFWdrawtextfun draw_text;
         GLFWcurrentselectionfun get_current_selection;
         GLFWhascurrentselectionfun has_current_selection;
+        GLFWimecursorpositionfun get_ime_cursor_position;
     } callbacks;
 
 

kitty/child-monitor.c

@@ -626,8 +626,16 @@ cursor_needs_render(Window *w) {
 static bool
 collect_cursor_info(CursorRenderInfo *ans, Window *w, monotonic_t now, OSWindow *os_window) {
     ScreenRenderData *rd = &w->render_data;
-    Cursor *cursor = rd->screen->cursor;
-    ans->x = cursor->x; ans->y = cursor->y;
+    Cursor *cursor;
+    if (screen_is_overlay_active(rd->screen)) {
+        // Do not force the cursor to be visible here for the sake of some programs that prefer it hidden
+        cursor = &(rd->screen->overlay_line.original_line.cursor);
+        ans->x = rd->screen->overlay_line.cursor_x;
+        ans->y = rd->screen->overlay_line.ynum;
+    } else {
+        cursor = rd->screen->cursor;
+        ans->x = cursor->x; ans->y = cursor->y;
+    }
     ans->is_visible = false;
     if (rd->screen->scrolled_by || !screen_is_cursor_visible(rd->screen)) return cursor_needs_render(w);
     monotonic_t time_since_start_blink = now - os_window->cursor_blink_zero_time;

kitty/glfw-wrapper.c

@@ -44,6 +44,9 @@ load_glfw(const char* path) {
     *(void **) (&glfwSetHasCurrentSelectionCallback_impl) = dlsym(handle, "glfwSetHasCurrentSelectionCallback");
     if (glfwSetHasCurrentSelectionCallback_impl == NULL) fail("Failed to load glfw function glfwSetHasCurrentSelectionCallback with error: %s", dlerror());
 
+    *(void **) (&glfwSetIMECursorPositionCallback_impl) = dlsym(handle, "glfwSetIMECursorPositionCallback");
+    if (glfwSetIMECursorPositionCallback_impl == NULL) fail("Failed to load glfw function glfwSetIMECursorPositionCallback with error: %s", dlerror());
+
     *(void **) (&glfwTerminate_impl) = dlsym(handle, "glfwTerminate");
     if (glfwTerminate_impl == NULL) fail("Failed to load glfw function glfwTerminate with error: %s", dlerror());
 

kitty/glfw-wrapper.h

@@ -1470,6 +1470,7 @@ typedef enum {
 } GLFWClipboardType;
 typedef GLFWDataChunk (* GLFWclipboarditerfun)(const char *mime_type, void *iter, GLFWClipboardType ctype);
 typedef bool (* GLFWclipboardwritedatafun)(void *object, const char *data, size_t sz);
+typedef bool (* GLFWimecursorpositionfun)(GLFWwindow *window, GLFWIMEUpdateEvent *ev);
 
 /*! @brief Video mode type.
  *
@@ -1667,6 +1668,10 @@ typedef GLFWhascurrentselectionfun (*glfwSetHasCurrentSelectionCallback_func)(GL
 GFW_EXTERN glfwSetHasCurrentSelectionCallback_func glfwSetHasCurrentSelectionCallback_impl;
 #define glfwSetHasCurrentSelectionCallback glfwSetHasCurrentSelectionCallback_impl
 
+typedef GLFWimecursorpositionfun (*glfwSetIMECursorPositionCallback_func)(GLFWimecursorpositionfun);
+GFW_EXTERN glfwSetIMECursorPositionCallback_func glfwSetIMECursorPositionCallback_impl;
+#define glfwSetIMECursorPositionCallback glfwSetIMECursorPositionCallback_impl
+
 typedef void (*glfwTerminate_func)(void);
 GFW_EXTERN glfwTerminate_func glfwTerminate_impl;
 #define glfwTerminate glfwTerminate_impl

kitty/glfw.c

@@ -507,6 +507,26 @@ has_current_selection(void) {
     return ans;
 }
 
+void prepare_ime_position_update_event(OSWindow *osw, Window *w, Screen *screen, GLFWIMEUpdateEvent *ev);
+
+static bool
+get_ime_cursor_position(GLFWwindow *glfw_window, GLFWIMEUpdateEvent *ev) {
+    if (!set_callback_window(glfw_window)) return false;
+    bool ans = false;
+    OSWindow *osw = global_state.callback_os_window;
+    if (osw && osw->is_focused && is_window_ready_for_callbacks()) {
+        Tab *tab = osw->tabs + osw->active_tab;
+        Window *w = tab->windows + tab->active_window;
+        Screen *screen = w->render_data.screen;
+        if (screen) {
+            prepare_ime_position_update_event(osw, w, screen, ev);
+            ans = true;
+        }
+    }
+    global_state.callback_os_window = NULL;
+    return ans;
+}
+
 
 static void get_window_dpi(GLFWwindow *w, double *x, double *y);
 
@@ -832,6 +852,7 @@ create_os_window(PyObject UNUSED *self, PyObject *args, PyObject *kw) {
         glfwSetApplicationCloseCallback(application_close_requested_callback);
         glfwSetCurrentSelectionCallback(get_current_selection);
         glfwSetHasCurrentSelectionCallback(has_current_selection);
+        glfwSetIMECursorPositionCallback(get_ime_cursor_position);
 #ifdef __APPLE__
         cocoa_set_activation_policy(OPT(macos_hide_from_tasks));
         glfwWindowHint(GLFW_COCOA_GRAPHICS_SWITCHING, true);

kitty/keys.c

@@ -102,13 +102,25 @@ update_ime_focus(OSWindow *osw, bool focused) {
 }
 
 void
-update_ime_position(Window* w, Screen *screen) {
-    unsigned int cell_width = global_state.callback_os_window->fonts_data->cell_width, cell_height = global_state.callback_os_window->fonts_data->cell_height;
+prepare_ime_position_update_event(OSWindow *osw, Window *w, Screen *screen, GLFWIMEUpdateEvent *ev) {
+    unsigned int cell_width = osw->fonts_data->cell_width, cell_height = osw->fonts_data->cell_height;
     unsigned int left = w->geometry.left, top = w->geometry.top;
-    left += screen->cursor->x * cell_width;
-    top += screen->cursor->y * cell_height;
+    if (screen_is_overlay_active(screen)) {
+        left += screen->overlay_line.cursor_x * cell_width;
+        top += MIN(screen->overlay_line.ynum + screen->scrolled_by, screen->lines - 1) * cell_height;
+    } else {
+        left += screen->cursor->x * cell_width;
+        top += screen->cursor->y * cell_height;
+    }
+    ev->cursor.left = left; ev->cursor.top = top; ev->cursor.width = cell_width; ev->cursor.height = cell_height;
+}
+
+void
+update_ime_position(Window* w UNUSED, Screen *screen UNUSED) {
     GLFWIMEUpdateEvent ev = { .type = GLFW_IME_UPDATE_CURSOR_POSITION };
-    ev.cursor.left = left; ev.cursor.top = top; ev.cursor.width = cell_width; ev.cursor.height = cell_height;
+#ifndef __APPLE__
+    prepare_ime_position_update_event(global_state.callback_os_window, w, screen, &ev);
+#endif
     glfwUpdateIMEState(global_state.callback_os_window->handle, &ev);
 }
 
@@ -154,12 +166,12 @@ on_key_input(GLFWkeyevent *ev) {
         case GLFW_IME_WAYLAND_DONE_EVENT:
             // If we update IME position here it sends GNOME's text input system into
             // an infinite loop. See https://github.com/kovidgoyal/kitty/issues/5105
-            screen_draw_overlay_text(screen, NULL);
+            screen_update_overlay_text(screen, NULL);
             debug("handled wayland IME done event\n");
             return;
         case GLFW_IME_PREEDIT_CHANGED:
+            screen_update_overlay_text(screen, text);
             update_ime_position(w, screen);
-            screen_draw_overlay_text(screen, text);
             debug("updated pre-edit text: '%s'\n", text);
             return;
         case GLFW_IME_COMMIT_TEXT:
@@ -167,7 +179,7 @@ on_key_input(GLFWkeyevent *ev) {
                 schedule_write_to_child(w->id, 1, text, strlen(text));
                 debug("committed pre-edit text: %s\n", text);
             } else debug("committed pre-edit text: (null)\n");
-            screen_draw_overlay_text(screen, NULL);
+            screen_update_overlay_text(screen, NULL);
             return;
         case GLFW_IME_NONE:
             // for macOS, update ime position on every key input

kitty/screen.c

@@ -23,6 +23,7 @@
 #include "unicode-data.h"
 #include "modes.h"
 #include "wcwidth-std.h"
+#include "wcswidth.h"
 #include "control-codes.h"
 #include "charsets.h"
 #include "keys.h"
@@ -49,25 +50,37 @@ init_tabstops(bool *tabstops, index_type count) {
 }
 
 static bool
-init_overlay_line(Screen *self, index_type columns) {
+init_overlay_line(Screen *self, index_type columns, bool keep_active) {
     PyMem_Free(self->overlay_line.cpu_cells);
     PyMem_Free(self->overlay_line.gpu_cells);
+    PyMem_Free(self->overlay_line.original_line.cpu_cells);
+    PyMem_Free(self->overlay_line.original_line.gpu_cells);
     self->overlay_line.cpu_cells = PyMem_Calloc(columns, sizeof(CPUCell));
     self->overlay_line.gpu_cells = PyMem_Calloc(columns, sizeof(GPUCell));
-    if (!self->overlay_line.cpu_cells || !self->overlay_line.gpu_cells) {
+    self->overlay_line.original_line.cpu_cells = PyMem_Calloc(columns, sizeof(CPUCell));
+    self->overlay_line.original_line.gpu_cells = PyMem_Calloc(columns, sizeof(GPUCell));
+    if (!self->overlay_line.cpu_cells || !self->overlay_line.gpu_cells ||
+        !self->overlay_line.original_line.cpu_cells || !self->overlay_line.original_line.gpu_cells) {
         PyErr_NoMemory(); return false;
     }
-    self->overlay_line.is_active = false;
-    self->overlay_line.xnum = 0;
+    if (!keep_active) {
+        self->overlay_line.is_active = false;
+        self->overlay_line.xnum = 0;
+    }
+    self->overlay_line.is_dirty = true;
     self->overlay_line.ynum = 0;
     self->overlay_line.xstart = 0;
+    self->overlay_line.cursor_x = 0;
+    self->overlay_line.last_ime_pos.x = 0;
+    self->overlay_line.last_ime_pos.y = 0;
+
     return true;
 }
 
-static void save_overlay_line(Screen *self, const char* func_name);
-static void restore_overlay_line(Screen *self);
 static void deactivate_overlay_line(Screen *self);
-static void clear_saved_overlay_line(Screen *self);
+static void update_overlay_position(Screen *self);
+static void render_overlay_line(Screen *self, Line *line, FONTS_DATA_HANDLE fonts_data);
+static void update_overlay_line_data(Screen *self, uint8_t *data);
 
 #define RESET_CHARSETS \
         self->g0_charset = translation_table(0); \
@@ -144,8 +157,7 @@ new(PyTypeObject *type, PyObject *args, PyObject UNUSED *kwds) {
         init_tabstops(self->main_tabstops, self->columns);
         init_tabstops(self->alt_tabstops, self->columns);
         self->key_encoding_flags = self->main_key_encoding_flags;
-        if (!init_overlay_line(self, self->columns)) { Py_CLEAR(self); return NULL; }
-        clear_saved_overlay_line(self);
+        if (!init_overlay_line(self, self->columns, false)) { Py_CLEAR(self); return NULL; }
         self->hyperlink_pool = alloc_hyperlink_pool();
         if (!self->hyperlink_pool) { Py_CLEAR(self); return PyErr_NoMemory(); }
         self->as_ansi_buf.hyperlink_pool = self->hyperlink_pool;
@@ -158,8 +170,11 @@ static Line* range_line_(Screen *self, int y);
 void
 screen_reset(Screen *self) {
     if (self->linebuf == self->alt_linebuf) screen_toggle_screen_buffer(self, true, true);
-    if (self->overlay_line.is_active) deactivate_overlay_line(self);
-    clear_saved_overlay_line(self);
+    if (screen_is_overlay_active(self)) {
+        deactivate_overlay_line(self);
+        // Cancel IME composition
+        update_ime_position_for_window(self->window_id, false, -1);
+    }
     Py_CLEAR(self->last_reported_cwd);
     self->render_unfocused_cursor = false;
     memset(self->main_key_encoding_flags, 0, sizeof(self->main_key_encoding_flags));
@@ -336,7 +351,6 @@ found:
 
 static bool
 screen_resize(Screen *self, unsigned int lines, unsigned int columns) {
-    if (self->overlay_line.is_active) save_overlay_line(self, __func__);
     lines = MAX(1u, lines); columns = MAX(1u, columns);
 
     bool is_main = self->linebuf == self->main_linebuf;
@@ -361,7 +375,7 @@ screen_resize(Screen *self, unsigned int lines, unsigned int columns) {
     which.num_content_lines = num_content_lines_after; \
 }
     // Resize overlay line
-    if (!init_overlay_line(self, columns)) return false;
+    if (!init_overlay_line(self, columns, true)) return false;
 
     // Resize main linebuf
     HistoryBuf *nh = realloc_hb(self->historybuf, self->historybuf->ynum, columns, &self->as_ansi_buf);
@@ -426,7 +440,6 @@ screen_resize(Screen *self, unsigned int lines, unsigned int columns) {
         self->linebuf->line->cpu_cells[0].ch = 0;
         self->cursor->x = 0;
     }
-    restore_overlay_line(self);
     return true;
 }
 
@@ -463,7 +476,9 @@ dealloc(Screen* self) {
     Py_CLEAR(self->marker);
     PyMem_Free(self->overlay_line.cpu_cells);
     PyMem_Free(self->overlay_line.gpu_cells);
-    Py_CLEAR(self->overlay_line.save.overlay_text);
+    PyMem_Free(self->overlay_line.original_line.cpu_cells);
+    PyMem_Free(self->overlay_line.original_line.gpu_cells);
+    Py_CLEAR(self->overlay_line.overlay_text);
     PyMem_Free(self->main_tabstops);
     free(self->pending_mode.buf);
     free(self->selections.items);
@@ -661,7 +676,6 @@ draw_combining_char(Screen *self, char_type ch) {
     }
 }
 
-
 static void
 draw_codepoint(Screen *self, char_type och, bool from_input_stream) {
     if (is_ignored_char(och)) return;
@@ -713,87 +727,11 @@ draw_codepoint(Screen *self, char_type och, bool from_input_stream) {
     linebuf_mark_line_dirty(self->linebuf, self->cursor->y);
 }
 
-void
-screen_draw_overlay_text(Screen *self, const char *utf8_text) {
-    if (self->overlay_line.is_active) deactivate_overlay_line(self);
-    if (self->overlay_line.save.overlay_text) clear_saved_overlay_line(self);
-    if (!utf8_text || !utf8_text[0]) return;
-    Line *line = range_line_(self, self->cursor->y);
-    if (!line) return;
-    line_save_cells(line, 0, self->columns, self->overlay_line.gpu_cells, self->overlay_line.cpu_cells);
-    self->overlay_line.is_active = true;
-    self->overlay_line.ynum = self->cursor->y;
-    self->overlay_line.xstart = self->cursor->x;
-    self->overlay_line.xnum = 0;
-    uint32_t codepoint = 0; UTF8State state = UTF8_ACCEPT;
-    bool orig_line_wrap_mode = self->modes.mDECAWM;
-    self->modes.mDECAWM = false;
-    self->cursor->reverse ^= true;
-    index_type before;
-    while (*utf8_text) {
-        switch(decode_utf8(&state, &codepoint, *(utf8_text++))) {
-            case UTF8_ACCEPT:
-                before = self->cursor->x;
-                draw_codepoint(self, codepoint, false);
-                self->overlay_line.xnum += self->cursor->x - before;
-                break;
-            case UTF8_REJECT:
-                break;
-        }
-    }
-    self->cursor->reverse ^= true;
-    self->modes.mDECAWM = orig_line_wrap_mode;
-}
-
-static PyObject*
-get_overlay_text(Screen *self) {
-#define ol self->overlay_line
-    if (ol.ynum >= self->lines || ol.xnum >= self->columns || !ol.xnum) return NULL;
-    Line *line = range_line_(self, ol.ynum);
-    if (!line) return NULL;
-    return unicode_in_range(line, ol.xstart, ol.xstart + ol.xnum, true, false, true);
-#undef ol
-}
-
-static void
-save_overlay_line(Screen *self, const char* func_name) {
-    if (self->overlay_line.is_active && screen_is_cursor_visible(self)) {
-        Py_XDECREF(self->overlay_line.save.overlay_text);
-        self->overlay_line.save.overlay_text = get_overlay_text(self);
-        self->overlay_line.save.func_name = func_name;
-        deactivate_overlay_line(self);
-    }
-}
-
-static void
-restore_overlay_line(Screen *self) {
-    if (self->overlay_line.save.overlay_text && screen_is_cursor_visible(self)) {
-        debug("Received input from child (%s) while overlay active. Overlay contents: %s\n", self->overlay_line.save.func_name, PyUnicode_AsUTF8(self->overlay_line.save.overlay_text));
-        screen_draw_overlay_text(self, PyUnicode_AsUTF8(self->overlay_line.save.overlay_text));
-        clear_saved_overlay_line(self);
-        update_ime_position_for_window(self->window_id, false, 0);
-    }
-}
-
-static void
-clear_saved_overlay_line(Screen *self) {
-    Py_CLEAR(self->overlay_line.save.overlay_text);
-}
-
-static void
-restore_overlay_line_from_cleanup(Screen **self) {
-    restore_overlay_line(*self);
-}
-
-#define MOVE_OVERLAY_LINE_WITH_CURSOR Screen __attribute__ ((__cleanup__(restore_overlay_line_from_cleanup))) *_sol_ = self; save_overlay_line(_sol_, __func__);
-
 void
 screen_draw(Screen *self, uint32_t och, bool from_input_stream) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     draw_codepoint(self, och, from_input_stream);
 }
 
-
 void
 screen_align(Screen *self) {
     self->margin_top = 0; self->margin_bottom = self->lines - 1;
@@ -819,7 +757,6 @@ screen_alignment_display(Screen *self) {
 
 void
 select_graphic_rendition(Screen *self, int *params, unsigned int count, Region *region_) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;  // needed in case colors have changed
     if (region_) {
         Region region = *region_;
         if (!region.top) region.top = 1;
@@ -1018,14 +955,7 @@ set_mode_from_const(Screen *self, unsigned int mode, bool val) {
             self->modes.mDECCKM = val;
             break;
         case DECTCEM:
-            if(!val) {
-                save_overlay_line(self, __func__);
-                self->modes.mDECTCEM = val;
-            } else {
-                self->modes.mDECTCEM = val;
-                if (self->overlay_line.is_active && !self->overlay_line.save.overlay_text) save_overlay_line(self, __func__);
-                restore_overlay_line(self);
-            }
+            self->modes.mDECTCEM = val;
             break;
         case DECSCNM:
             // Render screen in reverse video
@@ -1191,7 +1121,6 @@ screen_backspace(Screen *self) {
 
 void
 screen_tab(Screen *self) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     // Move to the next tab space, or the end of the screen if there aren't anymore left.
     unsigned int found = 0;
     for (unsigned int i = self->cursor->x + 1; i < self->columns; i++) {
@@ -1223,7 +1152,6 @@ screen_tab(Screen *self) {
 
 void
 screen_backtab(Screen *self, unsigned int count) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     // Move back count tabs
     if (!count) count = 1;
     int i;
@@ -1261,7 +1189,6 @@ screen_set_tab_stop(Screen *self) {
 
 void
 screen_cursor_back(Screen *self, unsigned int count/*=1*/, int move_direction/*=-1*/) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     if (count == 0) count = 1;
     if (move_direction < 0 && count > self->cursor->x) self->cursor->x = 0;
     else self->cursor->x += move_direction * count;
@@ -1275,13 +1202,12 @@ screen_cursor_forward(Screen *self, unsigned int count/*=1*/) {
 
 void
 screen_cursor_up(Screen *self, unsigned int count/*=1*/, bool do_carriage_return/*=false*/, int move_direction/*=-1*/) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     bool in_margins = cursor_within_margins(self);
     if (count == 0) count = 1;
     if (move_direction < 0 && count > self->cursor->y) self->cursor->y = 0;
     else self->cursor->y += move_direction * count;
-    screen_ensure_bounds(self, true, in_margins);
     if (do_carriage_return) self->cursor->x = 0;
+    screen_ensure_bounds(self, true, in_margins);
 }
 
 void
@@ -1301,7 +1227,6 @@ screen_cursor_down1(Screen *self, unsigned int count/*=1*/) {
 
 void
 screen_cursor_to_column(Screen *self, unsigned int column) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     unsigned int x = MAX(column, 1u) - 1;
     if (x != self->cursor->x) {
         self->cursor->x = x;
@@ -1328,7 +1253,6 @@ screen_cursor_to_column(Screen *self, unsigned int column) {
 
 void
 screen_index(Screen *self) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     // Move cursor down one line, scrolling screen if needed
     unsigned int top = self->margin_top, bottom = self->margin_bottom;
     if (self->cursor->y == bottom) {
@@ -1338,7 +1262,6 @@ screen_index(Screen *self) {
 
 void
 screen_scroll(Screen *self, unsigned int count) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     // Scroll the screen up by count lines, not moving the cursor
     unsigned int top = self->margin_top, bottom = self->margin_bottom;
     while (count > 0) {
@@ -1349,7 +1272,6 @@ screen_scroll(Screen *self, unsigned int count) {
 
 void
 screen_reverse_index(Screen *self) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     // Move cursor up one line, scrolling screen if needed
     unsigned int top = self->margin_top, bottom = self->margin_bottom;
     if (self->cursor->y == top) {
@@ -1359,7 +1281,6 @@ screen_reverse_index(Screen *self) {
 
 static void
 _reverse_scroll(Screen *self, unsigned int count, bool fill_from_scrollback) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     // Scroll the screen down by count lines, not moving the cursor
     unsigned int top = self->margin_top, bottom = self->margin_bottom;
     fill_from_scrollback = fill_from_scrollback && self->linebuf == self->main_linebuf;
@@ -1389,7 +1310,6 @@ screen_reverse_scroll_and_fill_from_scrollback(Screen *self, unsigned int count)
 void
 screen_carriage_return(Screen *self) {
     if (self->cursor->x != 0) {
-        MOVE_OVERLAY_LINE_WITH_CURSOR;
         self->cursor->x = 0;
     }
 }
@@ -1449,7 +1369,7 @@ copy_specific_mode(Screen *self, unsigned int mode, const ScreenModes *src, Scre
         SIMPLE_MODE(BRACKETED_PASTE)
         SIMPLE_MODE(FOCUS_TRACKING)
         SIMPLE_MODE(DECCKM)
-        SIDE_EFFECTS(DECTCEM)  // side effect: redraw IME overlay line
+        SIMPLE_MODE(DECTCEM)
         SIMPLE_MODE(DECAWM)
         case MOUSE_BUTTON_TRACKING: case MOUSE_MOTION_TRACKING: case MOUSE_MOVE_TRACKING:
             dest->mouse_tracking_mode = src->mouse_tracking_mode; break;
@@ -1504,7 +1424,6 @@ screen_save_modes(Screen *self) {
 
 void
 screen_restore_cursor(Screen *self) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     Savepoint *sp = self->linebuf == self->main_linebuf ? &self->main_savepoint : &self->alt_savepoint;
     if (!sp->is_valid) {
         screen_cursor_position(self, 1, 1);
@@ -1542,7 +1461,6 @@ screen_ensure_bounds(Screen *self, bool force_use_margins/*=false*/, bool in_mar
 
 void
 screen_cursor_position(Screen *self, unsigned int line, unsigned int column) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     bool in_margins = cursor_within_margins(self);
     line = (line == 0 ? 1 : line) - 1;
     column = (column == 0 ? 1: column) - 1;
@@ -1737,6 +1655,7 @@ screen_insert_lines(Screen *self, unsigned int count) {
 
 static void
 screen_scroll_until_cursor_prompt(Screen *self) {
+    bool in_margins = cursor_within_margins(self);
     int q = screen_cursor_at_a_shell_prompt(self);
     unsigned int y = q > -1 ? (unsigned int)q : self->cursor->y;
     unsigned int num_lines_to_scroll = MIN(self->margin_bottom, y);
@@ -1744,6 +1663,7 @@ screen_scroll_until_cursor_prompt(Screen *self) {
     self->cursor->y = self->margin_bottom;
     while (num_lines_to_scroll--) screen_index(self);
     self->cursor->y = final_y;
+    screen_ensure_bounds(self, false, in_margins);
 }
 
 void
@@ -1785,7 +1705,6 @@ screen_repeat_character(Screen *self, unsigned int count) {
 
 void
 screen_delete_characters(Screen *self, unsigned int count) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     // Delete characters, later characters are moved left
     const unsigned int bottom = self->lines ? self->lines - 1 : 0;
     if (count == 0) count = 1;
@@ -1803,7 +1722,6 @@ screen_delete_characters(Screen *self, unsigned int count) {
 
 void
 screen_erase_characters(Screen *self, unsigned int count) {
-    MOVE_OVERLAY_LINE_WITH_CURSOR;
     // Delete characters replacing them by spaces
     if (count == 0) count = 1;
     unsigned int x = self->cursor->x;
@@ -2280,11 +2198,13 @@ screen_has_marker(Screen *self) {
 
 void
 screen_update_cell_data(Screen *self, void *address, FONTS_DATA_HANDLE fonts_data, bool cursor_has_moved) {
+    const bool is_overlay_active = screen_is_overlay_active(self);
     unsigned int history_line_added_count = self->history_line_added_count;
     index_type lnum;
     bool was_dirty = self->is_dirty;
-    if (self->scrolled_by) self->scrolled_by = MIN(self->scrolled_by + history_line_added_count, self->historybuf->count);
     screen_reset_dirty(self);
+    update_overlay_position(self);
+    if (self->scrolled_by) self->scrolled_by = MIN(self->scrolled_by + history_line_added_count, self->historybuf->count);
     self->scroll_changed = false;
     for (index_type y = 0; y < MIN(self->lines, self->scrolled_by); y++) {
         lnum = self->scrolled_by - 1 - y;
@@ -2303,11 +2223,18 @@ screen_update_cell_data(Screen *self, void *address, FONTS_DATA_HANDLE fonts_dat
             (cursor_has_moved && (self->cursor->y == lnum || self->last_rendered.cursor_y == lnum))) {
             render_line(fonts_data, self->linebuf->line, lnum, self->cursor, self->disable_ligatures);
             if (self->linebuf->line->attrs.has_dirty_text && screen_has_marker(self)) mark_text_in_line(self->marker, self->linebuf->line);
-
+            if (is_overlay_active && lnum == self->overlay_line.ynum) render_overlay_line(self, self->linebuf->line, fonts_data);
             linebuf_mark_line_clean(self->linebuf, lnum);
         }
         update_line_data(self->linebuf->line, y, address);
     }
+    if (is_overlay_active && self->overlay_line.ynum + self->scrolled_by < self->lines) {
+        if (self->overlay_line.is_dirty) {
+            linebuf_init_line(self->linebuf, self->overlay_line.ynum);
+            render_overlay_line(self, self->linebuf->line, fonts_data);
+        }
+        update_overlay_line_data(self, address);
+    }
     if (was_dirty) clear_selection(&self->url_ranges);
 }
 
@@ -2696,22 +2623,6 @@ screen_open_url(Screen *self) {
     return found;
 }
 
-static void
-deactivate_overlay_line(Screen *self) {
-    if (self->overlay_line.is_active && self->overlay_line.xnum && self->overlay_line.ynum < self->lines) {
-        Line *line = range_line_(self, self->overlay_line.ynum);
-        line_reset_cells(line, self->overlay_line.xstart, self->overlay_line.xnum, self->overlay_line.gpu_cells, self->overlay_line.cpu_cells);
-        if (self->cursor->y == self->overlay_line.ynum) self->cursor->x = self->overlay_line.xstart;
-        self->is_dirty = true;
-        linebuf_mark_line_dirty(self->linebuf, self->overlay_line.ynum);
-    }
-    self->overlay_line.is_active = false;
-    self->overlay_line.ynum = 0;
-    self->overlay_line.xnum = 0;
-    self->overlay_line.xstart = 0;
-}
-
-
 // }}}
 
 // URLs {{{
@@ -2792,7 +2703,136 @@ screen_detect_url(Screen *screen, unsigned int x, unsigned int y) {
     return has_url ? -1 : 0;
 }
 
+// }}}
 
+// IME Overlay {{{
+bool
+screen_is_overlay_active(Screen *self) {
+    return self->overlay_line.is_active;
+}
+
+static void
+deactivate_overlay_line(Screen *self) {
+    if (self->overlay_line.is_active && self->overlay_line.xnum && self->overlay_line.ynum < self->lines) {
+        self->is_dirty = true;
+        linebuf_mark_line_dirty(self->linebuf, self->overlay_line.ynum);
+    }
+    self->overlay_line.is_active = false;
+    self->overlay_line.is_dirty = true;
+    self->overlay_line.ynum = 0;
+    self->overlay_line.xstart = 0;
+    self->overlay_line.cursor_x = 0;
+}
+
+void
+screen_update_overlay_text(Screen *self, const char *utf8_text) {
+    if (screen_is_overlay_active(self)) deactivate_overlay_line(self);
+    if (!utf8_text || !utf8_text[0]) return;
+    PyObject *text = PyUnicode_FromString(utf8_text);
+    if (!text) return;
+    Py_XDECREF(self->overlay_line.overlay_text);
+    // Calculate the total number of cells for initial overlay cursor position
+    PyObject *text_len = wcswidth_std(NULL, text);
+    self->overlay_line.overlay_text = text;
+    self->overlay_line.is_active = true;
+    self->overlay_line.is_dirty = true;
+    self->overlay_line.xstart = self->cursor->x;
+    self->overlay_line.xnum = !text_len ? 0 : PyLong_AsLong(text_len);
+    self->overlay_line.cursor_x = MIN(self->overlay_line.xstart + self->overlay_line.xnum, self->columns);
+    self->overlay_line.ynum = self->cursor->y;
+    cursor_copy_to(self->cursor, &(self->overlay_line.original_line.cursor));
+    linebuf_mark_line_dirty(self->linebuf, self->overlay_line.ynum);
+    self->is_dirty = true;
+    // Since we are typing, scroll to the bottom
+    if (self->scrolled_by != 0) {
+        self->scrolled_by = 0;
+        self->scroll_changed = true;
+    }
+}
+
+static void
+screen_draw_overlay_line(Screen *self) {
+    if (!self->overlay_line.overlay_text) return;
+    const char *utf8_text = PyUnicode_AsUTF8(self->overlay_line.overlay_text);
+    if (!utf8_text || !utf8_text[0]) return;
+    self->overlay_line.xnum = 0;
+    uint32_t codepoint = 0; UTF8State state = UTF8_ACCEPT;
+    bool orig_line_wrap_mode = self->modes.mDECAWM;
+    bool orig_cursor_enable_mode = self->modes.mDECTCEM;
+    bool orig_insert_replace_mode = self->modes.mIRM;
+    self->modes.mDECAWM = false;
+    self->modes.mDECTCEM = false;
+    self->modes.mIRM = false;
+    Cursor *orig_cursor = self->cursor;
+    self->cursor = &(self->overlay_line.original_line.cursor);
+    self->cursor->reverse ^= true;
+    self->cursor->x = self->overlay_line.xstart;
+    self->cursor->y = self->overlay_line.ynum;
+    self->overlay_line.xnum = 0;
+    index_type before;
+    while (*utf8_text) {
+        switch(decode_utf8(&state, &codepoint, *(utf8_text++))) {
+            case UTF8_ACCEPT:
+                before = self->cursor->x;
+                draw_codepoint(self, codepoint, false);
+                self->overlay_line.xnum += self->cursor->x - before;
+                break;
+            case UTF8_REJECT:
+                break;
+        }
+    }
+    self->overlay_line.cursor_x = self->cursor->x;
+    self->cursor->reverse ^= true;
+    self->cursor = orig_cursor;
+    self->modes.mDECAWM = orig_line_wrap_mode;
+    self->modes.mDECTCEM = orig_cursor_enable_mode;
+    self->modes.mIRM = orig_insert_replace_mode;
+}
+
+static void
+update_overlay_position(Screen *self) {
+    if (screen_is_overlay_active(self) && screen_is_cursor_visible(self)) {
+        bool cursor_update = false;
+        if (self->cursor->x != self->overlay_line.xstart) {
+            cursor_update = true;
+            self->overlay_line.xstart = self->cursor->x;
+            self->overlay_line.cursor_x = MIN(self->overlay_line.xstart + self->overlay_line.xnum, self->columns);
+        }
+        if (self->cursor->y != self->overlay_line.ynum) {
+            cursor_update = true;
+            linebuf_mark_line_dirty(self->linebuf, self->overlay_line.ynum);
+            self->overlay_line.ynum = self->cursor->y;
+        }
+        if (cursor_update) {
+            linebuf_mark_line_dirty(self->linebuf, self->overlay_line.ynum);
+            self->overlay_line.is_dirty = true;
+            self->is_dirty = true;
+        }
+    }
+}
+
+static void
+render_overlay_line(Screen *self, Line *line, FONTS_DATA_HANDLE fonts_data) {
+#define ol self->overlay_line
+    line_save_cells(line, 0, line->xnum, ol.original_line.gpu_cells, ol.original_line.cpu_cells);
+    screen_draw_overlay_line(self);
+    render_line(fonts_data, line, ol.ynum, self->cursor, self->disable_ligatures);
+    line_save_cells(line, 0, line->xnum, ol.gpu_cells, ol.cpu_cells);
+    line_reset_cells(line, 0, line->xnum, ol.original_line.gpu_cells, ol.original_line.cpu_cells);
+    ol.is_dirty = false;
+    const index_type y = MIN(ol.ynum + self->scrolled_by, self->lines - 1);
+    if (ol.last_ime_pos.x != ol.cursor_x || ol.last_ime_pos.y != y) {
+        ol.last_ime_pos.x = ol.cursor_x; ol.last_ime_pos.y = y;
+        update_ime_position_for_window(self->window_id, false, 0);
+    }
+#undef ol
+}
+
+static void
+update_overlay_line_data(Screen *self, uint8_t *data) {
+    const size_t base = sizeof(GPUCell) * (self->overlay_line.ynum + self->scrolled_by) * self->columns;
+    memcpy(data + base, self->overlay_line.gpu_cells, self->columns * sizeof(GPUCell));
+}
 
 // }}}
 
@@ -3921,7 +3961,7 @@ focus_changed(Screen *self, PyObject *has_focus_) {
     if (has_focus != previous) {
         self->has_focus = has_focus;
         if (has_focus) self->has_activity_since_last_focus = false;
-        else if (self->overlay_line.is_active) deactivate_overlay_line(self);
+        else if (screen_is_overlay_active(self)) deactivate_overlay_line(self);
         if (self->modes.mFOCUS_TRACKING) write_escape_code_to_child(self, CSI, has_focus ? "I" : "O");
         Py_RETURN_TRUE;
     }

kitty/screen.h

@@ -68,15 +68,20 @@ typedef struct {
 
 
 typedef struct {
+    PyObject *overlay_text;
     CPUCell *cpu_cells;
     GPUCell *gpu_cells;
+    index_type xstart, ynum, xnum, cursor_x;
     bool is_active;
-    index_type xstart, ynum, xnum;
-
+    bool is_dirty;
     struct {
-        PyObject *overlay_text;
-        const char *func_name;
-    } save;
+        CPUCell *cpu_cells;
+        GPUCell *gpu_cells;
+        Cursor cursor;
+    } original_line;
+    struct {
+        index_type x, y;
+    } last_ime_pos;
 } OverlayLine;
 
 typedef struct {
@@ -264,7 +269,8 @@ void screen_dirty_sprite_positions(Screen *self);
 void screen_rescale_images(Screen *self);
 void screen_report_size(Screen *, unsigned int which);
 void screen_manipulate_title_stack(Screen *, unsigned int op, unsigned int which);
-void screen_draw_overlay_text(Screen *self, const char *utf8_text);
+bool screen_is_overlay_active(Screen *self);
+void screen_update_overlay_text(Screen *self, const char *utf8_text);
 void screen_set_key_encoding_flags(Screen *self, uint32_t val, uint32_t how);
 void screen_push_key_encoding_flags(Screen *self, uint32_t val);
 void screen_pop_key_encoding_flags(Screen *self, uint32_t num);

kitty/shaders.c

@@ -329,7 +329,7 @@ cell_update_uniform_block(ssize_t vao_idx, Screen *screen, int uniform_buffer, c
     // Cursor position
     enum { BLOCK_IDX = 0, BEAM_IDX = NUM_UNDERLINE_STYLES + 3, UNDERLINE_IDX = NUM_UNDERLINE_STYLES + 4, UNFOCUSED_IDX = NUM_UNDERLINE_STYLES + 5 };
     if (cursor->is_visible) {
-        rd->cursor_x = screen->cursor->x, rd->cursor_y = screen->cursor->y;
+        rd->cursor_x = cursor->x, rd->cursor_y = cursor->y;
         if (cursor->is_focused) {
             switch(cursor->shape) {
                 default:
@@ -341,11 +341,11 @@ cell_update_uniform_block(ssize_t vao_idx, Screen *screen, int uniform_buffer, c
             }
         } else rd->cursor_fg_sprite_idx = UNFOCUSED_IDX;
         color_type cell_fg = rd->default_fg, cell_bg = rd->default_bg;
-        index_type cell_color_x = screen->cursor->x;
-        bool cursor_ok = screen->cursor->x < screen->columns && screen->cursor->y < screen->lines;
+        index_type cell_color_x = cursor->x;
+        bool cursor_ok = cursor->x < screen->columns && cursor->y < screen->lines;
         bool reversed = false;
         if (cursor_ok) {
-            linebuf_init_line(screen->linebuf, screen->cursor->y);
+            linebuf_init_line(screen->linebuf, cursor->y);
             colors_for_cell(screen->linebuf->line, screen->color_profile, &cell_color_x, &cell_fg, &cell_bg, &reversed);
         }
         if (IS_SPECIAL_COLOR(cursor_color)) {