From ec9b47d1136d7063666dc0aa548bf790f8b55a19 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Thu, 19 Jan 2017 21:48:02 -0500
Subject: [PATCH] Add cursor crosshairs

---
 src/gui/BufferPane.cc | 48 ++++++++++++++++++++++++++++++++++++++++++-
 src/gui/BufferPane.h  |  1 +
 2 files changed, 48 insertions(+), 1 deletion(-)

diff --git a/src/gui/BufferPane.cc b/src/gui/BufferPane.cc
index 58e3865..242c964 100644
--- a/src/gui/BufferPane.cc
+++ b/src/gui/BufferPane.cc
@@ -310,6 +310,33 @@ int BufferPane::draw_buffer_line(int screen_row, const Buffer::Iterator & start_
         int draw_row = screen_row + row_offset;
         if ((draw_row >= 0) && (draw_row <= m_rows))
         {
+            if (i.line() == m_iterator->line())
+            {
+                int row = draw_row;
+                int col = screen_column;
+                for (int i = 0; i < character_width; i++)
+                {
+                    draw_crosshair(col_x(col), row_y(row));
+                    col++;
+                    if (col >= m_columns)
+                    {
+                        row++;
+                        col = 0;
+                    }
+                }
+            }
+            else if ((m_cursor_virtual_column >= virtual_column) &&
+                    (m_cursor_virtual_column < (virtual_column + std::max(character_width, 1))))
+            {
+                int col = screen_column + (m_cursor_virtual_column - virtual_column);
+                int row = draw_row;
+                while (screen_column >= m_columns)
+                {
+                    screen_column -= m_columns;
+                    row++;
+                }
+                draw_crosshair(col_x(col), row_y(row));
+            }
             if (i == *m_iterator)
             {
                 bool wrap = (code_point == '\t');
@@ -327,7 +354,19 @@ int BufferPane::draw_buffer_line(int screen_row, const Buffer::Iterator & start_
                     }
                 }
             }
-            draw_character(code_point, draw_row, screen_column);
+            if ((code_point == '\n') || (code_point == Buffer::Iterator::INVALID_CODE_POINT))
+            {
+                if ((m_cursor_virtual_column > virtual_column) &&
+                        (m_cursor_virtual_column < (virtual_column + (m_columns - screen_column))))
+                {
+                    draw_crosshair(col_x(screen_column + (m_cursor_virtual_column - virtual_column)),
+                            row_y(draw_row));
+                }
+            }
+            else
+            {
+                draw_character(code_point, draw_row, screen_column);
+            }
             if ((code_point != '\n') && (code_point != Buffer::Iterator::INVALID_CODE_POINT))
             {
                 saved_row_offset = row_offset;
@@ -413,6 +452,13 @@ void BufferPane::draw_cursor(int x, int y, int i, int columns)
     }
 }
 
+void BufferPane::draw_crosshair(int x, int y)
+{
+    int width = m_window->font()->get_advance();
+    int height = m_window->font()->get_line_height();
+    m_window->gl()->draw_rect(win_x(x), win_y(y), width, height, 0.1, 0.1, 0.1, 1.0);
+}
+
 void BufferPane::exit_insert_mode()
 {
     if (insert_mode())
diff --git a/src/gui/BufferPane.h b/src/gui/BufferPane.h
index 5f50bdf..e798b1c 100644
--- a/src/gui/BufferPane.h
+++ b/src/gui/BufferPane.h
@@ -46,6 +46,7 @@ protected:
     void draw_character(uint32_t character, int screen_row, int screen_column);
     int character_width(uint32_t character);
     void draw_cursor(int x, int y, int i, int columns);
+    void draw_crosshair(int x, int y);
     int calculate_rows_in_cursor_line(const Buffer::Iterator & start_of_line);
     int calculate_rows_in_line_with_iterator_offset(const Buffer::Iterator & start_of_line, const Buffer::Iterator & reference, int * iterator_row_offset);
     int screen_rows_below_line(const Buffer::Iterator & line);