improve window render, malvim draft, fixes

src/utils.rs

@@ -0,0 +1,28 @@
+
+//the tuple is first, line #, actual line
+pub fn calc_actual_lines<'a>(lines: impl Iterator<Item = &'a String>, max_chars_per_line: usize) -> Vec<(bool, usize, String)> {
+  let mut actual_lines = Vec::new();
+  let mut line_num = 0;
+  for real_line in lines {
+    let mut line = real_line.to_string();
+    let mut first = true;
+    loop {
+      if line.chars().count() <= max_chars_per_line {
+        actual_lines.push((first, line_num, line));
+        break;
+      } else {
+        let mut line_chars = line.chars();
+        let mut push_string = String::new();
+        for _i in 0..max_chars_per_line {
+          push_string += &line_chars.next().unwrap().to_string();
+        }
+        actual_lines.push((first, line_num, push_string));
+        line = line_chars.collect();
+      }
+      first = false;
+    }
+    line_num += 1;
+  }
+  actual_lines
+}
+