reduce flicker in refresh

Author: daanx

src/editline.c

@@ -208,7 +208,7 @@ static bool edit_refresh_rows_iter(
   if (row < info->first_row) return false;
   if (row > info->last_row)  return true; // should not occur
 
-  term_clear_line(term);
+  // term_clear_line(term);
   edit_write_prompt(info->env, info->eb, row, info->in_extra);
 
   //' write output
@@ -228,8 +228,12 @@ static bool edit_refresh_rows_iter(
       bbcode_print( info->env->bbcode, "[ic-dim]\xE2\x86\xB5" ); // return symbol
       #endif
     }
+    term_clear_to_end_of_line(term);
     term_writeln(term, "");
   }
+  else {
+    term_clear_to_end_of_line(term);
+  }
   return (row >= info->last_row);  
 }
 
@@ -316,6 +320,7 @@ static void edit_refresh(ic_env_t* env, editor_t* eb)
   buffer_mode_t bmode = term_set_buffer_mode(env->term, BUFFERED);        
 
   // back up to the first line
+  term_start_of_line(env->term);
   term_up(env->term, (eb->cur_row >= termh ? termh-1 : eb->cur_row) );
   // term_clear_lines_to_end(env->term);  // gives flicker in old Windows cmd prompt 
 

src/term.c

@@ -101,6 +101,10 @@ ic_private void term_clear_line(term_t* term) {
   term_write( term, "\r" IC_CSI "K");
 }
 
+ic_private void term_clear_to_end_of_line(term_t* term) {
+  term_write(term, IC_CSI "K");
+}
+
 ic_private void term_start_of_line(term_t* term) {
   term_write( term, "\r" );
 }
@@ -603,9 +607,10 @@ static void term_erase_line( term_t* term, ssize_t mode ) {
   COORD start;
   ssize_t length;
   if (mode == 2) {
-    // to end of line    
-    length = (ssize_t)info.srWindow.Right - info.dwCursorPosition.X + 1;
-    start  = info.dwCursorPosition;
+    // entire line
+    start.X = 0;
+    start.Y = info.dwCursorPosition.Y;
+    length = (ssize_t)info.srWindow.Right + 1;
   }
   else if (mode == 1) {
     // to start of line
@@ -614,10 +619,9 @@ static void term_erase_line( term_t* term, ssize_t mode ) {
     length  = info.dwCursorPosition.X;
   }
   else {
-    // entire line
-    start.X = 0;
-    start.Y = info.dwCursorPosition.Y;
-    length = (ssize_t)info.srWindow.Right + 1;
+    // to end of line    
+    length = (ssize_t)info.srWindow.Right - info.dwCursorPosition.X + 1;
+    start = info.dwCursorPosition;
   }
   FillConsoleOutputAttribute( term->hcon, term->hcon_default_attr, (DWORD)length, start, &written );
   FillConsoleOutputCharacterA( term->hcon, ' ', (DWORD)length, start, &written );

src/term.h

@@ -60,6 +60,7 @@ ic_private void term_up(term_t* term, ssize_t n);
 ic_private void term_down(term_t* term, ssize_t n);
 ic_private void term_start_of_line(term_t* term );
 ic_private void term_clear_line(term_t* term);
+ic_private void term_clear_to_end_of_line(term_t* term);
 // ic_private void term_clear_lines_to_end(term_t* term);