Move selection render tracking into the Screen class

kitty/char_grid.py

@@ -96,7 +96,6 @@ class CharGrid:
     def __init__(self, screen, opts):
         self.vao_id = None
         self.screen_reversed = False
-        self.last_rendered_selection = None
         self.render_data = None
         self.data_buffer_size = None
         self.screen = screen
@@ -239,12 +238,9 @@ class CharGrid:
         if self.screen.scroll_changed or self.screen.is_dirty:
             self.update_cell_data(cell_program)
         sg = self.render_data
-        sel = self.screen.selection_limits()
+        if self.screen.is_selection_dirty():
-        selection_changed = sel != self.last_rendered_selection
-        if selection_changed:
             with cell_program.mapped_vertex_data(self.vao_id, self.selection_buffer_size, bufnum=1) as address:
                 self.screen.apply_selection(address, self.selection_buffer_size)
-            self.last_rendered_selection = sel
         return sg
 
     def render_cells(self, sg, cell_program, sprites, invert_colors=False):

kitty/data-types.h

@@ -220,6 +220,10 @@ typedef struct {
 #define PARSER_BUF_SZ (8 * 1024)
 #define READ_BUF_SZ (1024*1024)
 
+typedef struct {
+    unsigned int x, y;
+} SelectionBoundary;
+
 typedef struct {
     unsigned int start_x, start_y, start_scrolled_by, end_x, end_y, end_scrolled_by;
     bool in_progress;
@@ -228,10 +232,11 @@ typedef struct {
 typedef struct {
     PyObject_HEAD
 
-    unsigned int columns, lines, margin_top, margin_bottom, charset, scrolled_by;
+    unsigned int columns, lines, margin_top, margin_bottom, charset, scrolled_by, last_selection_scrolled_by;
     uint32_t utf8_state, utf8_codepoint, *g0_charset, *g1_charset, *g_charset;
     Selection selection;
-    bool use_latin1;
+    SelectionBoundary last_rendered_selection_start, last_rendered_selection_end;
+    bool use_latin1, selection_updated_once;
     Cursor *cursor;
     SavepointBuffer main_savepoints, alt_savepoints;
     PyObject *callbacks, *is_dirty, *cursor_changed, *scroll_changed;

kitty/screen.c

@@ -1247,10 +1247,6 @@ is_selection_empty(Screen *self, unsigned int start_x, unsigned int start_y, uns
     return (start_x >= self->columns || start_y >= self->lines || end_x >= self->columns || end_y >= self->lines || (start_x == end_x && start_y == end_y)) ? true : false;
 }
 
-typedef struct {
-    unsigned int x, y;
-} SelectionBoundary;
-
 static inline void
 selection_coord(Screen *self, unsigned int x, unsigned int y, unsigned int ydelta, SelectionBoundary *ans) {
     if (y + self->scrolled_by < ydelta) {
@@ -1278,11 +1274,14 @@ static PyObject*
 apply_selection(Screen *self, PyObject *args) {
     unsigned int size;
     PyObject *l;
-    SelectionBoundary start, end;
+#define start (self->last_rendered_selection_start)
+#define end (self->last_rendered_selection_end)
     if (!PyArg_ParseTuple(args, "O!I", &PyLong_Type, &l, &size)) return NULL;
     float *data = PyLong_AsVoidPtr(l);
     memset(data, 0, size);
     selection_limits_(self, &start, &end);
+    self->last_selection_scrolled_by = self->scrolled_by;
+    self->selection_updated_once = true;
     if (is_selection_empty(self, start.x, start.y, end.x, end.y)) { Py_RETURN_NONE; }
     for (index_type y = start.y; y <= end.y; y++) {
         Line *line = visual_line_(self, y);
@@ -1292,6 +1291,8 @@ apply_selection(Screen *self, PyObject *args) {
         for (index_type x = (y == start.y ? start.x : 0); x < xlimit; x++) line_start[x] = 1.0;
     }
     Py_RETURN_NONE;
+#undef start
+#undef end
 }
 
 static PyObject*
@@ -1403,10 +1404,11 @@ is_selection_in_progress(Screen *self) {
 }
 
 static PyObject*
-selection_limits(Screen *self) {
+is_selection_dirty(Screen *self) {
     SelectionBoundary start, end;
     selection_limits_(self, &start, &end);
-    return Py_BuildValue("(II)(II)", start.x, start.y, end.x, end.y);
+    if (self->last_selection_scrolled_by != self->scrolled_by || start.x != self->last_rendered_selection_start.x || start.y != self->last_rendered_selection_start.y || end.x != self->last_rendered_selection_end.x || end.y != self->last_rendered_selection_end.y || !self->selection_updated_once) { Py_RETURN_TRUE; }
+    Py_RETURN_FALSE;
 }
 
 static PyObject*
@@ -1519,7 +1521,7 @@ static PyMethodDef methods[] = {
     MND(text_for_selection, METH_NOARGS)
     MND(clear_selection, METH_NOARGS)
     MND(is_selection_in_progress, METH_NOARGS)
-    MND(selection_limits, METH_NOARGS)
+    MND(is_selection_dirty, METH_NOARGS)
     MND(start_selection, METH_VARARGS)
     MND(update_selection, METH_VARARGS)
     MND(scroll, METH_VARARGS)