Support double_width chars

src/render/model_clip_iterator.rs

@@ -4,25 +4,57 @@ use cairo;
 use super::context::CellMetrics;
 use ui_model;
 
+pub struct RowView<'a> {
+    pub row: usize,
+    pub line: &'a ui_model::Line,
+    pub cell_metrics: &'a CellMetrics,
+    pub line_y: f64,
+    pub ctx: &'a cairo::Context,
+}
+
+impl<'a> RowView<'a> {
+    pub fn new(
+        row: usize,
+        ctx: &'a cairo::Context,
+        cell_metrics: &'a CellMetrics,
+        line: &'a ui_model::Line,
+    ) -> Self {
+        RowView {
+            line,
+            line_y: row as f64 * cell_metrics.line_height,
+            row,
+            cell_metrics,
+            ctx,
+        }
+    }
+}
+
 pub struct ModelClipIterator<'a> {
     model_idx: usize,
     model_iter: Iter<'a, ui_model::Line>,
+    cell_metrics: &'a CellMetrics,
+    ctx: &'a cairo::Context,
 }
 
 pub trait ModelClipIteratorFactory {
-    fn get_clip_iterator(
-        &self,
-        ctx: &cairo::Context,
-        cell_metrics: &CellMetrics,
+    fn get_clip_iterator<'a>(
+        &'a self,
+        ctx: &'a cairo::Context,
+        cell_metrics: &'a CellMetrics,
     ) -> ModelClipIterator;
 }
 
 impl<'a> Iterator for ModelClipIterator<'a> {
-    type Item = (usize, &'a ui_model::Line);
+    type Item = RowView<'a>;
 
-    fn next(&mut self) -> Option<(usize, &'a ui_model::Line)> {
+    fn next(&mut self) -> Option<RowView<'a>> {
         let next = if let Some(line) = self.model_iter.next() {
-            Some((self.model_idx, line))
+            Some(RowView::new(
+                self.model_idx,
+                self.ctx,
+                self.cell_metrics,
+                line,
+            ))
         } else {
             None
         };
@@ -36,11 +68,11 @@ impl<'a> Iterator for ModelClipIterator<'a> {
 /// this is because in some cases(like 'g' character) drawing character does not fit to calculated bounds
 /// and if one line must be repainted - also previous and next line must be repainted to
 impl ModelClipIteratorFactory for ui_model::UiModel {
-    fn get_clip_iterator(
-        &self,
-        ctx: &cairo::Context,
-        cell_metrics: &CellMetrics,
-    ) -> ModelClipIterator {
+    fn get_clip_iterator<'a>(
+        &'a self,
+        ctx: &'a cairo::Context,
+        cell_metrics: &'a CellMetrics,
+    ) -> ModelClipIterator<'a> {
         let model = self.model();
 
         let (x1, y1, x2, y2) = ctx.clip_extents();
@@ -59,6 +91,8 @@ impl ModelClipIteratorFactory for ui_model::UiModel {
         ModelClipIterator {
             model_idx: model_clip_top,
             model_iter: model[model_clip_top..model_clip_bot + 1].iter(),
+            ctx,
+            cell_metrics,
         }
     }
 }