Save and restore correctly when drawing from static cache

Fixes #1424

src/renderer/atlas/StaticCharAtlas.ts

@@ -19,6 +19,10 @@ export default class StaticCharAtlas extends BaseCharAtlas {
     const canvas = this._document.createElement('canvas');
     canvas.width = width;
     canvas.height = height;
+
+    // This is useful for debugging
+    // document.body.appendChild(canvas);
+
     return canvas;
   }
 
@@ -65,6 +69,9 @@ export default class StaticCharAtlas extends BaseCharAtlas {
     if (!this._isCached(glyph, colorIndex)) {
       return false;
     }
+
+    ctx.save();
+
     // ImageBitmap's draw about twice as fast as from a canvas
     const charAtlasCellWidth = this._config.scaledCharWidth + CHAR_ATLAS_CELL_SPACING;
     const charAtlasCellHeight = this._config.scaledCharHeight + CHAR_ATLAS_CELL_SPACING;
@@ -86,6 +93,8 @@ export default class StaticCharAtlas extends BaseCharAtlas {
       this._config.scaledCharHeight
     );
 
+    ctx.restore();
+
     return true;
   }
 }