[igt-dev] [PATCH i-g-t 6/6] HACK: lib/igt_fb: Paint diagonals

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Paint diagonals on the standard test pattern so that scaling
artifacts are more readily visible.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 lib/igt_fb.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/lib/igt_fb.c b/lib/igt_fb.c
index 0c4fdc5d4889..cc57493e01c5 100644
--- a/lib/igt_fb.c
+++ b/lib/igt_fb.c
@@ -1479,6 +1479,18 @@ paint_marker(cairo_t *cr, int x, int y)
 	igt_cairo_printf_line(cr, align, 0, "(%d, %d)", x, y);
 }
 
+static void
+paint_diagonals(cairo_t *cr, int w, int h)
+{
+	cairo_move_to(cr, 0, 0);
+	cairo_line_to(cr, w, h);
+	cairo_move_to(cr, 0, h);
+	cairo_line_to(cr, w, 0);
+	cairo_set_source_rgb(cr, 1, 1, 1);
+	cairo_set_line_width(cr, 1);
+	cairo_stroke(cr);
+}
+
 /**
  * igt_paint_test_pattern:
  * @cr: cairo drawing context
@@ -1499,6 +1511,8 @@ void igt_paint_test_pattern(cairo_t *cr, int width, int height)
 
 	cairo_set_line_cap(cr, CAIRO_LINE_CAP_SQUARE);
 
+	paint_diagonals(cr, width, height);
+
 	/* Paint corner markers */
 	paint_marker(cr, 0, 0);
 	paint_marker(cr, width, 0);
-- 
2.24.1