Increase border width for test picture to be visible at 1x scale

piet/src/samples/picture_16.rs

@@ -1,8 +1,6 @@
-//! Clipping and clearing.
+//! capture_image_rect
 //!
-//! This tests interactions between clipping, transforms, and the clear method.
-//!
-//! 1. clear ignores clipping and transforms
+//! This tests makes sure that copying part of an image works
 
 use crate::kurbo::{Rect, Size};
 use crate::{Color, Error, InterpolationMode, RenderContext};
@@ -11,32 +9,39 @@ pub const SIZE: Size = Size::new(200., 200.);
 
 const RED: Color = Color::rgb8(255, 0, 0);
 const BLUE: Color = Color::rgb8(0, 0, 255);
+const INTERPOLATION_MODE: InterpolationMode = InterpolationMode::NearestNeighbor;
+const BORDER_WIDTH: f64 = 2.0;
 
 pub fn draw<R: RenderContext>(rc: &mut R) -> Result<(), Error> {
     rc.clear(None, Color::FUCHSIA);
 
-    let outer_rect = Rect::new(20., 20., 180., 180.);
-    let inner_rect = Rect::new(21., 21., 179., 179.);
-
-    let top_left_corner = Rect::new(5., 5., 50., 50.);
-    let top_right_corner = Rect::new(150., 5., 195., 50.);
-    let bottom_left_corner = Rect::new(5., 150., 50., 195.);
-    let bottom_right_corner = Rect::new(150., 150., 195., 195.);
+    let outer_rect_red = Rect::new(20., 20., 180., 180.);
+    let inner_rect_blue = Rect::new(
+        20. + BORDER_WIDTH,
+        20. + BORDER_WIDTH,
+        180. - BORDER_WIDTH,
+        180. - BORDER_WIDTH
+    );
 
     // Draw a box with a red border
-    rc.fill(outer_rect, &RED);
-    rc.fill(inner_rect, &BLUE);
+    rc.fill(outer_rect_red, &RED);
+    rc.fill(inner_rect_blue, &BLUE);
 
     // Cache the box, clear the image and re-draw the box from the cache
-    let cache = rc.capture_image_area(outer_rect).unwrap();
+    let cache = rc.capture_image_area(outer_rect_red).unwrap();
     rc.clear(None, Color::BLACK);
-    rc.draw_image(&cache, outer_rect, InterpolationMode::NearestNeighbor);
+    rc.draw_image(&cache, outer_rect_red, INTERPOLATION_MODE);
 
     // Draw the cached image, scaled, in all four corners of the image
-    rc.draw_image(&cache, top_left_corner, InterpolationMode::Bilinear);
-    rc.draw_image(&cache, top_right_corner, InterpolationMode::Bilinear);
-    rc.draw_image(&cache, bottom_left_corner, InterpolationMode::Bilinear);
-    rc.draw_image(&cache, bottom_right_corner, InterpolationMode::Bilinear);
+    let top_left_corner = Rect::new(5., 5., 50., 50.);
+    let top_right_corner = Rect::new(150., 5., 195., 50.);
+    let bottom_left_corner = Rect::new(5., 150., 50., 195.);
+    let bottom_right_corner = Rect::new(150., 150., 195., 195.);
+
+    rc.draw_image(&cache, top_left_corner, INTERPOLATION_MODE);
+    rc.draw_image(&cache, top_right_corner, INTERPOLATION_MODE);
+    rc.draw_image(&cache, bottom_left_corner, INTERPOLATION_MODE);
+    rc.draw_image(&cache, bottom_right_corner, INTERPOLATION_MODE);
 
     Ok(())
 }