From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Thu, 5 Jul 2018 22:45:53 +0000 (+0200)
Subject: Reject motion search if we go beyond the image boundary; seems to fix most of the... 
X-Git-Tag: 1.8.0~76^2~240
X-Git-Url: https://git.sesse.net/?a=commitdiff_plain;h=9cc95703513b137c304514f09867aea4c869748b;p=nageru

Reject motion search if we go beyond the image boundary; seems to fix most of the bad edge behavior.
---

diff --git a/motion_search.frag b/motion_search.frag
index a417834..262dca5 100644
--- a/motion_search.frag
+++ b/motion_search.frag
@@ -137,8 +137,14 @@ void main()
 		u -= (H_inv * du) * inv_image_size;
 	}
 
-	// Reject if we moved too far.
-	if (length((u - initial_u) * image_size) > patch_size) {
+	// Reject if we moved too far. Also reject if the patch goes out-of-bounds
+	// (the paper does not mention this, but the code does, and it seems to be
+	// critical to avoid really bad behavior at the edges).
+	if ((length((u - initial_u) * image_size) > patch_size) ||
+	     u.x * image_size.x < -(patch_size * 0.5f) ||
+	     (1.0 - u.x) * image_size.x < -(patch_size * 0.5f) ||
+	     u.y * image_size.y < -(patch_size * 0.5f) ||
+	     (1.0 - u.y) * image_size.y < -(patch_size * 0.5f)) {
 		u = initial_u;
 	}