From bc3309a328da8b351abd3de181ed3cea711b59fa Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Tue, 20 Dec 2016 20:22:19 -0500
Subject: [PATCH] Prepare for screen drawing again after Cursor removal.

Add BufferPane::character_width() to handle multi-column characters.
---
 src/gui/BufferPane.cc | 46 +++++++++++++++++++++++++++++++++----------
 src/gui/BufferPane.h  |  9 ++++-----
 2 files changed, 40 insertions(+), 15 deletions(-)

diff --git a/src/gui/BufferPane.cc b/src/gui/BufferPane.cc
index da7de76..55a8d37 100644
--- a/src/gui/BufferPane.cc
+++ b/src/gui/BufferPane.cc
@@ -3,11 +3,9 @@
 BufferPane::BufferPane(Window * window, std::shared_ptr<Buffer> buffer)
     : m_window(window), m_buffer(buffer)
 {
-    m_cursor_row = 0;
+    m_cursor_screen_row = 0;
     m_scroll_offset = 5;
-#if 0
-    m_cursor = buffer->add_cursor();
-#endif
+    m_iterator = buffer->add_iterator();
 }
 
 void BufferPane::resize(int width, int height)
@@ -58,9 +56,11 @@ int BufferPane::screen_rows_above_cursor(int stop_at)
 
 void BufferPane::draw()
 {
-#if 0
-    if (m_cursor->valid())
+    if (m_iterator->valid())
     {
+        Buffer::Iterator i = *m_iterator;
+        i.go_start_of_line();
+#if 0
         update_cursor_row();
         int screen_row = m_cursor_row - m_cursor->column() / m_columns;
         Buffer::Cursor iter_cursor = *m_cursor;
@@ -81,12 +81,12 @@ void BufferPane::draw()
                 break;
             }
         }
+#endif
     }
     else
     {
         draw_cursor(col_x(0), row_y(0), false);
     }
-#endif
 }
 
 #if 0
@@ -115,11 +115,38 @@ void BufferPane::draw_buffer_line(int screen_row, const Buffer::Cursor & cursor)
         iter_cursor.go_right(true);
     }
 }
+#endif
+
+int BufferPane::character_width(uint32_t character)
+{
+    if (character < 0x20u)
+    {
+        return 2;
+    }
+    else if (character < 0x80u)
+    {
+        return 1u;
+    }
+    else
+    {
+        return std::max(1, m_window->font()->get_glyph(character)->get_advance() / m_window->font()->get_advance());
+    }
+}
 
 void BufferPane::draw_buffer_character(int screen_column, int screen_row, uint32_t character)
 {
-    m_window->gl()->draw_character(win_x(col_x(screen_column)), win_y(row_y(screen_row)),
-            character, *m_window->font());
+    if (character < 0x20u)
+    {
+        m_window->gl()->draw_character(win_x(col_x(screen_column)), win_y(row_y(screen_row)),
+                '^', *m_window->font());
+        m_window->gl()->draw_character(win_x(col_x(screen_column + 1)), win_y(row_y(screen_row)),
+                (character - 0x20u + 'A'), *m_window->font());
+    }
+    else
+    {
+        m_window->gl()->draw_character(win_x(col_x(screen_column)), win_y(row_y(screen_row)),
+                character, *m_window->font());
+    }
 }
 
 void BufferPane::draw_cursor(int x, int y, bool insert_mode)
@@ -128,7 +155,6 @@ void BufferPane::draw_cursor(int x, int y, bool insert_mode)
     int height = m_window->font()->get_line_height();
     m_window->gl()->draw_rect(win_x(x), win_y(y), width, height, 1.0, 0.2, 1.0, 1.0);
 }
-#endif
 
 void BufferPane::handle_key(uint32_t keyval)
 {
diff --git a/src/gui/BufferPane.h b/src/gui/BufferPane.h
index 740658c..a537b09 100644
--- a/src/gui/BufferPane.h
+++ b/src/gui/BufferPane.h
@@ -36,9 +36,10 @@ protected:
     int screen_rows_above_cursor(int stop_at);
     void update_cursor_row();
     void draw_buffer_line(int screen_row, const Buffer::Cursor & cursor);
+#endif
+    int character_width(uint32_t character);
     void draw_buffer_character(int screen_column, int screen_row, uint32_t character);
     void draw_cursor(int x, int y, bool insert_mode);
-#endif
     int col_x(int col)
     {
         return col * m_window->font()->get_advance();
@@ -54,10 +55,8 @@ protected:
     int m_rows;
     int m_columns;
     int m_scroll_offset;
-    int m_cursor_row;
-#if 0
-    std::shared_ptr<Buffer::Cursor> m_cursor;
-#endif
+    int m_cursor_screen_row;
+    std::shared_ptr<Buffer::Iterator> m_iterator;
 };
 
 #endif