sway-patched-tray-menu-github/sway/tree/arrange.c
Pedro Côrte-Real 8008344762 Avoid numerical instability in resize
Because the layout code rounds down the dimensions of the windows
resizing would often be off by one pixel. The width/height fraction
would not exactly reflect the final computed width and so the resize
code would end up calculating things wrong.

To fix this first snap the container size fractions to the pixel grid
and only then do the resize. Also use round() instead of floor() during
layout to avoid a slightly too small width. This applies in two cases:

1. For the container we are actually resizing using floor() might result
   in being 1px too small.
2. For the other containers it might result in resizing them down by 1px
   and then if the container being resized is the last all those extra
   pixels would make the resize too large.

Fixes #4391
2020-01-01 10:14:29 -07:00

368 lines
11 KiB
C

#define _POSIX_C_SOURCE 200809L
#include <ctype.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <wlr/types/wlr_output.h>
#include <wlr/types/wlr_output_layout.h>
#include "sway/tree/arrange.h"
#include "sway/tree/container.h"
#include "sway/output.h"
#include "sway/tree/workspace.h"
#include "sway/tree/view.h"
#include "list.h"
#include "log.h"
static void apply_horiz_layout(list_t *children, struct wlr_box *parent) {
if (!children->length) {
return;
}
// Count the number of new windows we are resizing, and how much space
// is currently occupied
int new_children = 0;
double current_width_fraction = 0;
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
current_width_fraction += child->width_fraction;
if (child->width_fraction <= 0) {
new_children += 1;
}
}
// Calculate each height fraction
double total_width_fraction = 0;
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
if (child->width_fraction <= 0) {
if (current_width_fraction <= 0) {
child->width_fraction = 1.0;
} else if (children->length > new_children) {
child->width_fraction = current_width_fraction /
(children->length - new_children);
} else {
child->width_fraction = current_width_fraction;
}
}
total_width_fraction += child->width_fraction;
}
// Normalize width fractions so the sum is 1.0
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
child->width_fraction /= total_width_fraction;
}
// Calculate gap size
double inner_gap = 0;
struct sway_container *child = children->items[0];
struct sway_workspace *ws = child->workspace;
if (ws) {
inner_gap = ws->gaps_inner;
}
// Descendants of tabbed/stacked containers don't have gaps
struct sway_container *temp = child;
while (temp) {
enum sway_container_layout layout = container_parent_layout(temp);
if (layout == L_TABBED || layout == L_STACKED) {
inner_gap = 0;
}
temp = temp->parent;
}
double total_gap = fmin(inner_gap * (children->length - 1),
fmax(0, parent->width - MIN_SANE_W * children->length));
double child_total_width = parent->width - total_gap;
inner_gap = total_gap / (children->length - 1);
// Resize windows
sway_log(SWAY_DEBUG, "Arranging %p horizontally", 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 = round(child->width_fraction * child_total_width);
child->height = parent->height;
child_x += child->width + inner_gap;
// Make last child use remaining width of parent
if (i == children->length - 1) {
child->width = parent->x + parent->width - child->x;
}
}
}
static void apply_vert_layout(list_t *children, struct wlr_box *parent) {
if (!children->length) {
return;
}
// Count the number of new windows we are resizing, and how much space
// is currently occupied
int new_children = 0;
double current_height_fraction = 0;
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
current_height_fraction += child->height_fraction;
if (child->height_fraction <= 0) {
new_children += 1;
}
}
// Calculate each height fraction
double total_height_fraction = 0;
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
if (child->height_fraction <= 0) {
if (current_height_fraction <= 0) {
child->height_fraction = 1.0;
} else if (children->length > new_children) {
child->height_fraction = current_height_fraction /
(children->length - new_children);
} else {
child->height_fraction = current_height_fraction;
}
}
total_height_fraction += child->height_fraction;
}
// Normalize height fractions so the sum is 1.0
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
child->height_fraction /= total_height_fraction;
}
// Calculate gap size
double inner_gap = 0;
struct sway_container *child = children->items[0];
struct sway_workspace *ws = child->workspace;
if (ws) {
inner_gap = ws->gaps_inner;
}
// Descendants of tabbed/stacked containers don't have gaps
struct sway_container *temp = child;
while (temp) {
enum sway_container_layout layout = container_parent_layout(temp);
if (layout == L_TABBED || layout == L_STACKED) {
inner_gap = 0;
}
temp = temp->parent;
}
double total_gap = fmin(inner_gap * (children->length - 1),
fmax(0, parent->height - MIN_SANE_H * children->length));
double child_total_height = parent->height - total_gap;
inner_gap = total_gap / (children->length - 1);
// Resize windows
sway_log(SWAY_DEBUG, "Arranging %p vertically", 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 = round(child->height_fraction * child_total_height);
child_y += child->height + inner_gap;
// Make last child use remaining height of parent
if (i == children->length - 1) {
child->height = parent->y + parent->height - child->y;
}
}
}
static void apply_tabbed_layout(list_t *children, struct wlr_box *parent) {
if (!children->length) {
return;
}
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
int parent_offset = child->view ? 0 : container_titlebar_height();
child->x = parent->x;
child->y = parent->y + parent_offset;
child->width = parent->width;
child->height = parent->height - parent_offset;
}
}
static void apply_stacked_layout(list_t *children, struct wlr_box *parent) {
if (!children->length) {
return;
}
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
int parent_offset = child->view ? 0 :
container_titlebar_height() * children->length;
child->x = parent->x;
child->y = parent->y + parent_offset;
child->width = parent->width;
child->height = parent->height - parent_offset;
}
}
static void arrange_floating(list_t *floating) {
for (int i = 0; i < floating->length; ++i) {
struct sway_container *floater = floating->items[i];
arrange_container(floater);
}
}
static void arrange_children(list_t *children,
enum sway_container_layout layout, struct wlr_box *parent) {
// Calculate x, y, width and height of children
switch (layout) {
case L_HORIZ:
apply_horiz_layout(children, parent);
break;
case L_VERT:
apply_vert_layout(children, parent);
break;
case L_TABBED:
apply_tabbed_layout(children, parent);
break;
case L_STACKED:
apply_stacked_layout(children, parent);
break;
case L_NONE:
apply_horiz_layout(children, parent);
break;
}
// Recurse into child containers
for (int i = 0; i < children->length; ++i) {
struct sway_container *child = children->items[i];
arrange_container(child);
}
}
void arrange_container(struct sway_container *container) {
if (config->reloading) {
return;
}
if (container->view) {
view_autoconfigure(container->view);
node_set_dirty(&container->node);
return;
}
struct wlr_box box;
container_get_box(container, &box);
arrange_children(container->children, container->layout, &box);
node_set_dirty(&container->node);
}
void arrange_workspace(struct sway_workspace *workspace) {
if (config->reloading) {
return;
}
if (!workspace->output) {
// Happens when there are no outputs connected
return;
}
struct sway_output *output = workspace->output;
struct wlr_box *area = &output->usable_area;
sway_log(SWAY_DEBUG, "Usable area for ws: %dx%d@%d,%d",
area->width, area->height, area->x, area->y);
bool first_arrange = workspace->width == 0 && workspace->height == 0;
double prev_x = workspace->x - workspace->current_gaps.left;
double prev_y = workspace->y - workspace->current_gaps.top;
workspace->width = area->width;
workspace->height = area->height;
workspace->x = output->lx + area->x;
workspace->y = output->ly + area->y;
// Adjust any floating containers
double diff_x = workspace->x - prev_x;
double diff_y = workspace->y - prev_y;
if (!first_arrange && (diff_x != 0 || diff_y != 0)) {
for (int i = 0; i < workspace->floating->length; ++i) {
struct sway_container *floater = workspace->floating->items[i];
container_floating_translate(floater, diff_x, diff_y);
double center_x = floater->x + floater->width / 2;
double center_y = floater->y + floater->height / 2;
struct wlr_box workspace_box;
workspace_get_box(workspace, &workspace_box);
if (!wlr_box_contains_point(&workspace_box, center_x, center_y)) {
container_floating_move_to_center(floater);
}
}
}
workspace_add_gaps(workspace);
node_set_dirty(&workspace->node);
sway_log(SWAY_DEBUG, "Arranging workspace '%s' at %f, %f", workspace->name,
workspace->x, workspace->y);
if (workspace->fullscreen) {
struct sway_container *fs = workspace->fullscreen;
fs->x = output->lx;
fs->y = output->ly;
fs->width = output->width;
fs->height = output->height;
arrange_container(fs);
} else {
struct wlr_box box;
workspace_get_box(workspace, &box);
arrange_children(workspace->tiling, workspace->layout, &box);
arrange_floating(workspace->floating);
}
}
void arrange_output(struct sway_output *output) {
if (config->reloading) {
return;
}
const struct wlr_box *output_box = wlr_output_layout_get_box(
root->output_layout, output->wlr_output);
output->lx = output_box->x;
output->ly = output_box->y;
output->width = output_box->width;
output->height = output_box->height;
for (int i = 0; i < output->workspaces->length; ++i) {
struct sway_workspace *workspace = output->workspaces->items[i];
arrange_workspace(workspace);
}
}
void arrange_root(void) {
if (config->reloading) {
return;
}
const struct wlr_box *layout_box =
wlr_output_layout_get_box(root->output_layout, NULL);
root->x = layout_box->x;
root->y = layout_box->y;
root->width = layout_box->width;
root->height = layout_box->height;
if (root->fullscreen_global) {
struct sway_container *fs = root->fullscreen_global;
fs->x = root->x;
fs->y = root->y;
fs->width = root->width;
fs->height = root->height;
arrange_container(fs);
} else {
for (int i = 0; i < root->outputs->length; ++i) {
struct sway_output *output = root->outputs->items[i];
arrange_output(output);
}
}
}
void arrange_node(struct sway_node *node) {
switch (node->type) {
case N_ROOT:
arrange_root();
break;
case N_OUTPUT:
arrange_output(node->sway_output);
break;
case N_WORKSPACE:
arrange_workspace(node->sway_workspace);
break;
case N_CONTAINER:
arrange_container(node->sway_container);
break;
}
}