[rust] add example issue #1751

rust/examples/issue-1751.rs

@@ -0,0 +1,23 @@
+use libnotcurses_sys::*;
+
+const W: u32 = 32;
+const H: u32 = 32;
+
+fn main() -> NcResult<()> {
+    let nc = Notcurses::new()?;
+
+    // create a white rectangle
+    let buffer = vec![255; H as usize * W as usize * 4];
+    let v = NcVisual::from_rgba(buffer.as_slice(), H, W * 4, W)?;
+    let vo = NcVisualOptions::without_plane(0, 0, 0, 0, H, W, NCBLIT_PIXEL, 0, 0);
+
+    // BUG: render function fails when downsizing
+    v.resize(H / 2, W / 2)?;
+    v.render(nc, &vo)?;
+
+    rsleep![nc, 1];
+
+    v.destroy();
+    nc.stop()?;
+    Ok(())
+}

rust/src/visual/methods.rs

@@ -348,7 +348,7 @@ impl NcVisual {
     ) -> NcResult<&mut NcPlane> {
         error_ref_mut![
             unsafe { crate::ncvisual_render(nc, self, options) },
-            "NcVisual.render()"
+            "NcVisual.render(Notcurses, &NcVisualOptions)"
         ]
     }