From a72d1d728b345a156af863bc151986349b9aa6ef Mon Sep 17 00:00:00 2001
From: TC1995 <mariogplayer90@gmail.com>
Date: Sat, 11 Jul 2020 19:55:45 +0200
Subject: [PATCH] Fix horizontal screen bug in 15bpp mode of the 928.

---
 src/video/vid_s3.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/video/vid_s3.c b/src/video/vid_s3.c
index a86a20584..edefbf818 100644
--- a/src/video/vid_s3.c
+++ b/src/video/vid_s3.c
@@ -1651,8 +1651,13 @@ void s3_recalctimings(svga_t *svga)
 			break;
 			case 15:
 			svga->render = svga_render_15bpp_highres;
-			if (s3->chip != S3_VISION964 && s3->chip != S3_86C801 && s3->chip != S3_86C928 && s3->chip != S3_86C911)
-				svga->hdisp /= 2;
+			if (s3->chip != S3_VISION964 && s3->chip != S3_86C801)
+			{
+				if (s3->chip == S3_86C928)
+					svga->hdisp *= 2;
+				else
+					svga->hdisp /= 2;
+			}
 			break;
 			case 16: 
 			svga->render = svga_render_16bpp_highres;