sna: Add common widescreen resolutions

Currently we add fake modes to cater for applications that want to
change the screen size but limit themselves to only those that are
available, and do not wish to either use RandR scaling or their own. For
widescreen panels, these 4:3 aspect ratio modes require panel fitting
and so are less than satisfory. Since we add fake modes, let's add a few
common widescreen modes as well (choosing the right aspect ration for
the panel).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=37858
References: https://bugs.freedesktop.org/show_bug.cgi?id=29890
References: https://bugs.freedesktop.org/show_bug.cgi?id=89996
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 76 insertions, 0 deletions

diff --git a/src/sna/sna_display.c b/src/sna/sna_display.c
index 9e6c8cc4..944bb535 100644
--- a/src/sna/sna_display.c
+++ b/src/sna/sna_display.c
@@ -3259,10 +3259,40 @@ static bool duplicate_mode(DisplayModePtr modes, DisplayModePtr m)
 	return false;
 }
 
+static struct pixel_count {
+	int16_t width, height;
+} common_16_9[] = {
+	{ 640, 360 },
+	{ 720, 405 },
+	{ 864, 486 },
+	{ 960, 540 },
+	{ 1024, 576 },
+	{ 1280, 720 },
+	{ 1366, 768 },
+	{ 1600, 900 },
+	{ 1920, 1080 },
+	{ 2048, 1152 },
+	{ 2560, 1440 },
+	{ 2880, 1620 },
+	{ 3200, 1800 },
+	{ 3840, 2160 },
+	{ 4096, 2304 },
+	{ 5120, 2880 },
+	{ 7680, 4320 },
+	{ 15360, 8640 },
+}, common_16_10[] = {
+	{ 1280, 800 },
+	{ 1400, 900 },
+	{ 1680, 1050 },
+	{ 1920, 1200 },
+	{ 2560, 1600 },
+};
+
 static DisplayModePtr
 default_modes(DisplayModePtr preferred)
 {
 	DisplayModePtr modes;
+	int n;
 
 #if XORG_VERSION_CURRENT >= XORG_VERSION_NUMERIC(1,6,99,900,0)
 	modes = xf86GetDefaultModes();
@@ -3270,6 +3300,8 @@ default_modes(DisplayModePtr preferred)
 	modes = xf86GetDefaultModes(0, 0);
 #endif
 
+	/* XXX O(n^2) mode list generation :( */
+
 #if XORG_VERSION_CURRENT >= XORG_VERSION_NUMERIC(1,4,99,901,0)
 	if (preferred) {
 		DisplayModePtr m;
@@ -3283,6 +3315,50 @@ default_modes(DisplayModePtr preferred)
 			modes = xf86ModesAdd(modes, m);
 		else
 			free(m);
+
+		if (preferred->VDisplay * 16 > preferred->HDisplay*9 - preferred->HDisplay/32 &&
+		    preferred->VDisplay * 16 < preferred->HDisplay*9 + preferred->HDisplay/32) {
+			DBG(("Adding 16:9 modes -- %d < %d > %d\n",
+			     preferred->HDisplay*9 - preferred->HDisplay/32,
+			     preferred->VDisplay * 16,
+			     preferred->HDisplay*9 + preferred->HDisplay/32));
+			for (n = 0; n < ARRAY_SIZE(common_16_9); n++) {
+				if (preferred->HDisplay >= common_16_9[n].width ||
+				    preferred->VDisplay >= common_16_9[n].height)
+					break;
+
+				m = xf86GTFMode(common_16_9[n].width,
+						common_16_9[n].height,
+						xf86ModeVRefresh(preferred),
+						FALSE, FALSE);
+				if (!duplicate_mode(modes, m))
+					modes = xf86ModesAdd(modes, m);
+				else
+					free(m);
+			}
+		}
+
+		if (preferred->VDisplay * 16 > preferred->HDisplay*10 - preferred->HDisplay/32 &&
+		    preferred->VDisplay * 16 < preferred->HDisplay*10 + preferred->HDisplay/32) {
+			DBG(("Adding 16:10 modes -- %d < %d > %d\n",
+			     preferred->HDisplay*10 - preferred->HDisplay/32,
+			     preferred->VDisplay * 16,
+			     preferred->HDisplay*10 + preferred->HDisplay/32));
+			for (n = 0; n < ARRAY_SIZE(common_16_10); n++) {
+				if (preferred->HDisplay >= common_16_10[n].width ||
+				    preferred->VDisplay >= common_16_10[n].height)
+					break;
+
+				m = xf86GTFMode(common_16_10[n].width,
+						common_16_10[n].height,
+						xf86ModeVRefresh(preferred),
+						FALSE, FALSE);
+				if (!duplicate_mode(modes, m))
+					modes = xf86ModesAdd(modes, m);
+				else
+					free(m);
+			}
+		}
 	}
 #endif