Fixed biggest performance bottleneck on draw_user_interface: print white spaces.

3 files changed, 44 insertions, 36 deletions

diff --git a/modules/TUI/module.jai b/modules/TUI/module.jai
index 7c3a71d..a5db3bf 100644
--- a/modules/TUI/module.jai
+++ b/modules/TUI/module.jai
@@ -572,7 +572,7 @@ read_input_line :: (count_limit: int, is_visible: bool = true) -> string, Key {
                 idx += 1;
 
                 // Truncate string to avoid incomplete utf8 codes on the string tail.
-                truncate(*str, count_limit);
+                str.count = truncate(str, count_limit).count;
         }
     }
 
diff --git a/modules/UTF8.jai b/modules/UTF8.jai
index b583809..205e57d 100644
--- a/modules/UTF8.jai
+++ b/modules/UTF8.jai
@@ -21,15 +21,15 @@ count_character_bytes :: inline (leading_byte: u8) -> int {
     return 1;
 }
 
-// Truncates the string to the provided length and zeroes the discarded bytes.
-// Returns the length of truncated string or -1 if string has no data.
-truncate :: (str: *string, length: int) -> length: int {
-    if str.data == null     then return -1;
+// Returns the string (using same str.data) truncated to the provided length.
+truncate :: (str: string, length: int) -> string {
     
-    if str.count < length   then length = str.count;
+    if str.data == null     then return "";
+
+    if str.count < length   then return .{str.count, str.data};
     
-    data := str.data;
-    count := str.count;
+    data    := str.data;
+    count   := str.count;
 
     // Find index of first continuation byte.
     idx := length;
@@ -50,12 +50,10 @@ truncate :: (str: *string, length: int) -> length: int {
         && !(continuation_bytes == 2 && (data[idx - 1] & 0xF0) == 0xE0)
         && !(continuation_bytes == 3 && (data[idx - 1] & 0xF8) == 0xF0)
     ) {
-        length -= (continuation_bytes + 1); // Remove start byte, ence '+ 1'.
+        length -= (continuation_bytes + 1); // Remove start byte, hence '+ 1'.
     }
-
-    memset(data + length, 0, count - length);
-    str.count = length;
-    return length;
+    
+    return .{length, str.data};
 }
 
 // Returns true when the string is empty or consists of space characters.
@@ -78,13 +76,23 @@ is_empty :: (str: string) -> bool {
 }
 
 // Counts the number of characters.
-count_characters :: (str: string) -> int {
+count_characters :: (str: string, $is_null_terminated := false) -> int {
     characters := 0;
     idx := 0;
-    while idx < str.count {
-        idx += count_character_bytes(str[idx]);
-        characters += 1;
+    
+    #if is_null_terminated {
+        while idx < str.count && str[idx] != 0 {
+            idx += count_character_bytes(str[idx]);
+            characters += 1;
+        }
+    }
+    else {
+        while idx < str.count {
+            idx += count_character_bytes(str[idx]);
+            characters += 1;
+        }
     }
+    
     return characters;
 }
 
diff --git a/ttt.jai b/ttt.jai
index d8233f9..7d1559b 100644
--- a/ttt.jai
+++ b/ttt.jai
@@ -719,8 +719,8 @@ import_from_csv :: (db: *Database, path: string) -> bool {
             csv_values := split(line, ",",, temporary_allocator);
             
             // Truncate and import task name.
-            truncate(*csv_values[0], task.name.count);
-            memcpy(task.name.data, csv_values[0].data, csv_values[0].count);
+            task_name := truncate(csv_values[0], task.name.count);
+            memcpy(task.name.data, task_name.data, task_name.count);
             
             advance(*csv_values);
             for csv_values
@@ -901,11 +901,11 @@ draw_user_interface :: (db: *Database, layout: *Layout) {
 
     start := current_time_monotonic(); // DEBUG
 
-
-
-
-    // TODO During dirty_flag revamp...we may also start using the String_Builder. 
-
+    auto_release_temp();
+    
+    empty_line := talloc_string(size_x);
+    memset(empty_line.data, #char " ", size_x);
+    
     adjust_first_day_of_week := int.[
         (0 + FIRST_DAY_OF_WEEK) % NUM_WEEK_DAYS,
         (1 + FIRST_DAY_OF_WEEK) % NUM_WEEK_DAYS,
@@ -1004,6 +1004,7 @@ draw_user_interface :: (db: *Database, layout: *Layout) {
     idx_start := (db.selected_idx / layout_tasks_rows) * layout_tasks_rows;
     // Display up to rows allowed by the layout, or less if reached end of database.
     idx_stop := idx_start + (ifx layout_tasks_rows > db.tasks.count - idx_start then db.tasks.count - idx_start else layout_tasks_rows);
+    
     for task_idx: idx_start..idx_stop-1 {
         task := *db.tasks[task_idx];
         y += 1;
@@ -1026,19 +1027,18 @@ draw_user_interface :: (db: *Database, layout: *Layout) {
         // Task title.
         x += 1;
         column_width = layout.columns[L_TITLE_IDX].width;
-        // mvprintw(xx y, xx x, "%-*.*s", column_width, column_width, temp_c_string(xx task.name)); //task.name); TODO Fix required for LLVM/Cncurses. TODO DAM
-        // TODO FIXME OH MY GOD SUCH BAD CODEZ
+        // Print title.
+        //  When the column is wider than the name, we end up with the trailing zeros.
+        //  Thankfully, the trailing zeros are not printed so, it's all good.
+        task_name := cast(string)task.name;
+        task_name = truncate(task_name, column_width);
         TUI.set_cursor_position(x, y);
-        white_spaces := column_width;
-        // FIXME Improve by using buffer instead of printing one char at the time.
-        while white_spaces > 0 {
-            print_character(#char " ");
-            white_spaces -= 1;
-        }
-        TUI.set_cursor_position(x, y);
-        task_name: string = cast(string)task.name;
-        task_name.count = ifx task_name.count > column_width then column_width else task_name.count;
-        print("%", task_name);
+        write_string(task_name);
+        // Paint the remaining column space.
+        task_name_char_count := count_characters(task_name, is_null_terminated = true);
+        paint_remaining := string.{ column_width - task_name_char_count, empty_line.data };
+        write_string(paint_remaining);
+        
         x += column_width;
         
         // Task times.