2 files changed, 28 insertions, 6 deletions

diff --git a/sway/commands/resize.c b/sway/commands/resize.c
index 0c9af12d..7ff4ef7b 100644
--- a/sway/commands/resize.c
+++ b/sway/commands/resize.c
@@ -172,9 +172,19 @@ void container_resize_tiled(struct sway_container *con,
 		if (prev && prev->width - sibling_amount < MIN_SANE_W) {
 			return;
 		}
+		if (con->child_total_width <= 0) {
+			return;
+		}
+
+		// We're going to resize so snap all the width fractions to full pixels
+		// to avoid rounding issues
+		list_t *siblings = container_get_siblings(con);
+		for (int i = 0; i < siblings->length; ++i) {
+			struct sway_container *con = siblings->items[i];
+			con->width_fraction = con->width / con->child_total_width;
+		}
 
-		double amount_fraction =
-			((double)amount / con->width) * con->width_fraction;
+		double amount_fraction = (double)amount / con->child_total_width;
 		double sibling_amount_fraction =
 			prev ? amount_fraction / 2.0 : amount_fraction;
 
@@ -193,9 +203,19 @@ void container_resize_tiled(struct sway_container *con,
 		if (prev && prev->height - sibling_amount < MIN_SANE_H) {
 			return;
 		}
+		if (con->child_total_height <= 0) {
+			return;
+		}
+
+		// We're going to resize so snap all the height fractions to full pixels
+		// to avoid rounding issues
+		list_t *siblings = container_get_siblings(con);
+		for (int i = 0; i < siblings->length; ++i) {
+			struct sway_container *con = siblings->items[i];
+			con->height_fraction = con->height / con->child_total_height;
+		}
 
-		double amount_fraction =
-			((double)amount / con->height) * con->height_fraction;
+		double amount_fraction = (double)amount / con->child_total_height;
 		double sibling_amount_fraction =
 			prev ? amount_fraction / 2.0 : amount_fraction;
 
diff --git a/sway/tree/arrange.c b/sway/tree/arrange.c
index 7b88b3a2..e4f59110 100644
--- a/sway/tree/arrange.c
+++ b/sway/tree/arrange.c
@@ -78,9 +78,10 @@ static void apply_horiz_layout(list_t *children, struct wlr_box *parent) {
 	double child_x = parent->x;
 	for (int i = 0; i < children->length; ++i) {
 		struct sway_container *child = children->items[i];
+		child->child_total_width = child_total_width;
 		child->x = child_x;
 		child->y = parent->y;
-		child->width = floor(child->width_fraction * child_total_width);
+		child->width = round(child->width_fraction * child_total_width);
 		child->height = parent->height;
 		child_x += child->width + inner_gap;
 
@@ -156,10 +157,11 @@ static void apply_vert_layout(list_t *children, struct wlr_box *parent) {
 	double child_y = parent->y;
 	for (int i = 0; i < children->length; ++i) {
 		struct sway_container *child = children->items[i];
+		child->child_total_height = child_total_height;
 		child->x = parent->x;
 		child->y = child_y;
 		child->width = parent->width;
-		child->height = floor(child->height_fraction * child_total_height);
+		child->height = round(child->height_fraction * child_total_height);
 		child_y += child->height + inner_gap;
 
 		// Make last child use remaining height of parent