scratch/se-matrix 6bc6c5eb1d8 2/2: Copy desired frame matrix to desired terminal matrix

[Gerd Moellmann]

branch: scratch/se-matrix
commit 6bc6c5eb1d8525b8e0e431ab451762d545328d2d
Author: Gerd Möllmann <gerd@gnu.org>
Commit: Gerd Möllmann <gerd@gnu.org>

    Copy desired frame matrix to desired terminal matrix
---
 src/dispnew.c | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/src/dispnew.c b/src/dispnew.c
index a02d2fbe6ca..3635423f10c 100644
--- a/src/dispnew.c
+++ b/src/dispnew.c
@@ -4027,6 +4027,37 @@ copy_matrix (struct glyph_matrix *from, struct 
glyph_matrix **to,
     copy_row (from, m, i);
 }
 
+static void
+copy_desired_row (struct glyph_matrix *from_matrix,
+                 struct glyph_matrix *to_matrix, int i)
+{
+  struct glyph_row *from = from_matrix->rows + i;
+  struct glyph_row *to = to_matrix->rows + i;
+  copy_row_except_pointers (to, from);
+  for (int i = 0; i <= LAST_AREA; ++i)
+    to->used[i] = from->used[i];
+  memcpy (to->glyphs[0], from->glyphs[0],
+         to_matrix->matrix_w * sizeof (struct glyph));
+}
+
+static void
+copy_frame_desired_matrix (struct frame *root)
+{
+  struct glyph_matrix *from = root->frame_desired_matrix;
+  struct glyph_matrix *to = root->terminal_desired_matrix;
+  eassert (to->rows_allocated == from->rows_allocated);
+
+  struct glyph_pool *pool = to->pool;
+  struct glyph_row *rows = to->rows;
+  *to = *from;
+  to->pool = pool;
+  to->rows = rows;
+
+  for (int i = 0; i < to->rows_allocated; ++i)
+    if (from->rows[i].enabled_p)
+      copy_desired_row (from, to, i);
+}
+
 static void
 copy_pool_and_matrix (struct glyph_matrix *from,
                      struct glyph_pool **to_pool,
@@ -4096,6 +4127,15 @@ combine_updates_for_frame (struct frame *f, bool 
inhibit_scrolling)
   Lisp_Object z_order = frames_in_reverse_z_order (root, true);
   choose_frame_or_terminal_matrices (root, z_order);
 
+  /* FIXME: use frame_desired_matrix directly. Problem: making
+     make_matrix_current would make the terminal current matrix
+     have pointers to frame_desired_pool. Is this bad? */
+  if (is_using_terminal_matrices (root))
+    {
+      inhibit_scrolling = true;
+      copy_frame_desired_matrix (root);
+    }
+
   /* Process child frames in reverse z-order, topmost last.  For each
      child, copy what we need to the root's desired matrix.  */
   struct frame *topmost_child = NULL;