sway-patched-tray-menu-github/sway/commands/resize.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

618 lines
17 KiB
C

#include <errno.h>
#include <limits.h>
#include <math.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <wlr/util/edges.h>
#include "sway/commands.h"
#include "sway/tree/arrange.h"
#include "sway/tree/view.h"
#include "sway/tree/workspace.h"
#include "log.h"
#define AXIS_HORIZONTAL (WLR_EDGE_LEFT | WLR_EDGE_RIGHT)
#define AXIS_VERTICAL (WLR_EDGE_TOP | WLR_EDGE_BOTTOM)
enum resize_unit {
RESIZE_UNIT_PX,
RESIZE_UNIT_PPT,
RESIZE_UNIT_DEFAULT,
RESIZE_UNIT_INVALID,
};
struct resize_amount {
int amount;
enum resize_unit unit;
};
static enum resize_unit parse_resize_unit(const char *unit) {
if (strcasecmp(unit, "px") == 0) {
return RESIZE_UNIT_PX;
}
if (strcasecmp(unit, "ppt") == 0) {
return RESIZE_UNIT_PPT;
}
if (strcasecmp(unit, "default") == 0) {
return RESIZE_UNIT_DEFAULT;
}
return RESIZE_UNIT_INVALID;
}
// Parse arguments such as "10", "10px" or "10 px".
// Returns the number of arguments consumed.
static int parse_resize_amount(int argc, char **argv,
struct resize_amount *amount) {
char *err;
amount->amount = (int)strtol(argv[0], &err, 10);
if (*err) {
// e.g. 10px
amount->unit = parse_resize_unit(err);
return 1;
}
if (argc == 1) {
amount->unit = RESIZE_UNIT_DEFAULT;
return 1;
}
// Try the second argument
amount->unit = parse_resize_unit(argv[1]);
if (amount->unit == RESIZE_UNIT_INVALID) {
amount->unit = RESIZE_UNIT_DEFAULT;
return 1;
}
return 2;
}
static uint32_t parse_resize_axis(const char *axis) {
if (strcasecmp(axis, "width") == 0 || strcasecmp(axis, "horizontal") == 0) {
return AXIS_HORIZONTAL;
}
if (strcasecmp(axis, "height") == 0 || strcasecmp(axis, "vertical") == 0) {
return AXIS_VERTICAL;
}
if (strcasecmp(axis, "up") == 0) {
return WLR_EDGE_TOP;
}
if (strcasecmp(axis, "down") == 0) {
return WLR_EDGE_BOTTOM;
}
if (strcasecmp(axis, "left") == 0) {
return WLR_EDGE_LEFT;
}
if (strcasecmp(axis, "right") == 0) {
return WLR_EDGE_RIGHT;
}
return WLR_EDGE_NONE;
}
static bool is_horizontal(uint32_t axis) {
return axis & (WLR_EDGE_LEFT | WLR_EDGE_RIGHT);
}
struct sway_container *container_find_resize_parent(struct sway_container *con,
uint32_t axis) {
enum sway_container_layout parallel_layout =
is_horizontal(axis) ? L_HORIZ : L_VERT;
bool allow_first = axis != WLR_EDGE_TOP && axis != WLR_EDGE_LEFT;
bool allow_last = axis != WLR_EDGE_RIGHT && axis != WLR_EDGE_BOTTOM;
while (con) {
list_t *siblings = container_get_siblings(con);
int index = container_sibling_index(con);
if (container_parent_layout(con) == parallel_layout &&
siblings->length > 1 && (allow_first || index > 0) &&
(allow_last || index < siblings->length - 1)) {
return con;
}
con = con->parent;
}
return NULL;
}
void container_resize_tiled(struct sway_container *con,
uint32_t axis, int amount) {
if (!con) {
return;
}
con = container_find_resize_parent(con, axis);
if (!con) {
// Can't resize in this direction
return;
}
// For HORIZONTAL or VERTICAL, we are growing in two directions so select
// both adjacent siblings. For RIGHT or DOWN, just select the next sibling.
// For LEFT or UP, convert it to a RIGHT or DOWN resize and reassign con to
// the previous sibling.
struct sway_container *prev = NULL;
struct sway_container *next = NULL;
list_t *siblings = container_get_siblings(con);
int index = container_sibling_index(con);
if (axis == AXIS_HORIZONTAL || axis == AXIS_VERTICAL) {
if (index == 0) {
next = siblings->items[1];
} else if (index == siblings->length - 1) {
// Convert edge to top/left
next = con;
con = siblings->items[index - 1];
amount = -amount;
} else {
prev = siblings->items[index - 1];
next = siblings->items[index + 1];
}
} else if (axis == WLR_EDGE_TOP || axis == WLR_EDGE_LEFT) {
if (!sway_assert(index > 0, "Didn't expect first child")) {
return;
}
next = con;
con = siblings->items[index - 1];
amount = -amount;
} else {
if (!sway_assert(index < siblings->length - 1,
"Didn't expect last child")) {
return;
}
next = siblings->items[index + 1];
}
// Apply new dimensions
int sibling_amount = prev ? ceil((double)amount / 2.0) : amount;
if (is_horizontal(axis)) {
if (con->width + amount < MIN_SANE_W) {
return;
}
if (next->width - sibling_amount < MIN_SANE_W) {
return;
}
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->child_total_width;
double sibling_amount_fraction =
prev ? amount_fraction / 2.0 : amount_fraction;
con->width_fraction += amount_fraction;
next->width_fraction -= sibling_amount_fraction;
if (prev) {
prev->width_fraction -= sibling_amount_fraction;
}
} else {
if (con->height + amount < MIN_SANE_H) {
return;
}
if (next->height - sibling_amount < MIN_SANE_H) {
return;
}
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->child_total_height;
double sibling_amount_fraction =
prev ? amount_fraction / 2.0 : amount_fraction;
con->height_fraction += amount_fraction;
next->height_fraction -= sibling_amount_fraction;
if (prev) {
prev->height_fraction -= sibling_amount_fraction;
}
}
if (con->parent) {
arrange_container(con->parent);
} else {
arrange_workspace(con->workspace);
}
}
/**
* Implement `resize <grow|shrink>` for a floating container.
*/
static struct cmd_results *resize_adjust_floating(uint32_t axis,
struct resize_amount *amount) {
struct sway_container *con = config->handler_context.container;
int grow_width = 0, grow_height = 0;
if (is_horizontal(axis)) {
grow_width = amount->amount;
} else {
grow_height = amount->amount;
}
// Make sure we're not adjusting beyond floating min/max size
int min_width, max_width, min_height, max_height;
floating_calculate_constraints(&min_width, &max_width,
&min_height, &max_height);
if (con->width + grow_width < min_width) {
grow_width = min_width - con->width;
} else if (con->width + grow_width > max_width) {
grow_width = max_width - con->width;
}
if (con->height + grow_height < min_height) {
grow_height = min_height - con->height;
} else if (con->height + grow_height > max_height) {
grow_height = max_height - con->height;
}
int grow_x = 0, grow_y = 0;
if (axis == AXIS_HORIZONTAL) {
grow_x = -grow_width / 2;
} else if (axis == AXIS_VERTICAL) {
grow_y = -grow_height / 2;
} else if (axis == WLR_EDGE_TOP) {
grow_y = -grow_height;
} else if (axis == WLR_EDGE_LEFT) {
grow_x = -grow_width;
}
if (grow_x == 0 && grow_y == 0) {
return cmd_results_new(CMD_INVALID, "Cannot resize any further");
}
con->x += grow_x;
con->y += grow_y;
con->width += grow_width;
con->height += grow_height;
con->content_x += grow_x;
con->content_y += grow_y;
con->content_width += grow_width;
con->content_height += grow_height;
arrange_container(con);
return cmd_results_new(CMD_SUCCESS, NULL);
}
/**
* Implement `resize <grow|shrink>` for a tiled container.
*/
static struct cmd_results *resize_adjust_tiled(uint32_t axis,
struct resize_amount *amount) {
struct sway_container *current = config->handler_context.container;
if (amount->unit == RESIZE_UNIT_DEFAULT) {
amount->unit = RESIZE_UNIT_PPT;
}
if (amount->unit == RESIZE_UNIT_PPT) {
float pct = amount->amount / 100.0f;
if (is_horizontal(axis)) {
amount->amount = (float)current->width * pct;
} else {
amount->amount = (float)current->height * pct;
}
}
double old_width = current->width_fraction;
double old_height = current->height_fraction;
container_resize_tiled(current, axis, amount->amount);
if (current->width_fraction == old_width &&
current->height_fraction == old_height) {
return cmd_results_new(CMD_INVALID, "Cannot resize any further");
}
return cmd_results_new(CMD_SUCCESS, NULL);
}
/**
* Implement `resize set` for a tiled container.
*/
static struct cmd_results *resize_set_tiled(struct sway_container *con,
struct resize_amount *width, struct resize_amount *height) {
if (width->amount) {
if (width->unit == RESIZE_UNIT_PPT ||
width->unit == RESIZE_UNIT_DEFAULT) {
// Convert to px
struct sway_container *parent = con->parent;
while (parent && parent->layout != L_HORIZ) {
parent = parent->parent;
}
if (parent) {
width->amount = parent->width * width->amount / 100;
} else {
width->amount = con->workspace->width * width->amount / 100;
}
width->unit = RESIZE_UNIT_PX;
}
if (width->unit == RESIZE_UNIT_PX) {
container_resize_tiled(con, AXIS_HORIZONTAL,
width->amount - con->width);
}
}
if (height->amount) {
if (height->unit == RESIZE_UNIT_PPT ||
height->unit == RESIZE_UNIT_DEFAULT) {
// Convert to px
struct sway_container *parent = con->parent;
while (parent && parent->layout != L_VERT) {
parent = parent->parent;
}
if (parent) {
height->amount = parent->height * height->amount / 100;
} else {
height->amount = con->workspace->height * height->amount / 100;
}
height->unit = RESIZE_UNIT_PX;
}
if (height->unit == RESIZE_UNIT_PX) {
container_resize_tiled(con, AXIS_VERTICAL,
height->amount - con->height);
}
}
return cmd_results_new(CMD_SUCCESS, NULL);
}
/**
* Implement `resize set` for a floating container.
*/
static struct cmd_results *resize_set_floating(struct sway_container *con,
struct resize_amount *width, struct resize_amount *height) {
int min_width, max_width, min_height, max_height, grow_width = 0, grow_height = 0;
floating_calculate_constraints(&min_width, &max_width,
&min_height, &max_height);
if (width->amount) {
switch (width->unit) {
case RESIZE_UNIT_PPT:
if (container_is_scratchpad_hidden(con)) {
return cmd_results_new(CMD_FAILURE,
"Cannot resize a hidden scratchpad container by ppt");
}
// Convert to px
width->amount = con->workspace->width * width->amount / 100;
width->unit = RESIZE_UNIT_PX;
// Falls through
case RESIZE_UNIT_PX:
case RESIZE_UNIT_DEFAULT:
width->amount = fmax(min_width, fmin(width->amount, max_width));
grow_width = width->amount - con->width;
con->x -= grow_width / 2;
con->width = width->amount;
break;
case RESIZE_UNIT_INVALID:
sway_assert(false, "invalid width unit");
break;
}
}
if (height->amount) {
switch (height->unit) {
case RESIZE_UNIT_PPT:
if (container_is_scratchpad_hidden(con)) {
return cmd_results_new(CMD_FAILURE,
"Cannot resize a hidden scratchpad container by ppt");
}
// Convert to px
height->amount = con->workspace->height * height->amount / 100;
height->unit = RESIZE_UNIT_PX;
// Falls through
case RESIZE_UNIT_PX:
case RESIZE_UNIT_DEFAULT:
height->amount = fmax(min_height, fmin(height->amount, max_height));
grow_height = height->amount - con->height;
con->y -= grow_height / 2;
con->height = height->amount;
break;
case RESIZE_UNIT_INVALID:
sway_assert(false, "invalid height unit");
break;
}
}
con->content_x -= grow_width / 2;
con->content_y -= grow_height / 2;
con->content_width += grow_width;
con->content_height += grow_height;
arrange_container(con);
return cmd_results_new(CMD_SUCCESS, NULL);
}
/**
* resize set <args>
*
* args: [width] <width> [px|ppt]
* : height <height> [px|ppt]
* : [width] <width> [px|ppt] [height] <height> [px|ppt]
*/
static struct cmd_results *cmd_resize_set(int argc, char **argv) {
struct cmd_results *error;
if ((error = checkarg(argc, "resize", EXPECTED_AT_LEAST, 1))) {
return error;
}
const char usage[] = "Expected 'resize set [width] <width> [px|ppt]' or "
"'resize set height <height> [px|ppt]' or "
"'resize set [width] <width> [px|ppt] [height] <height> [px|ppt]'";
// Width
struct resize_amount width = {0};
if (argc >= 2 && !strcmp(argv[0], "width") && strcmp(argv[1], "height")) {
argc--; argv++;
}
if (strcmp(argv[0], "height")) {
int num_consumed_args = parse_resize_amount(argc, argv, &width);
argc -= num_consumed_args;
argv += num_consumed_args;
if (width.unit == RESIZE_UNIT_INVALID) {
return cmd_results_new(CMD_INVALID, usage);
}
}
// Height
struct resize_amount height = {0};
if (argc) {
if (argc >= 2 && !strcmp(argv[0], "height")) {
argc--; argv++;
}
int num_consumed_args = parse_resize_amount(argc, argv, &height);
if (argc > num_consumed_args) {
return cmd_results_new(CMD_INVALID, usage);
}
if (width.unit == RESIZE_UNIT_INVALID) {
return cmd_results_new(CMD_INVALID, usage);
}
}
// If 0, don't resize that dimension
struct sway_container *con = config->handler_context.container;
if (width.amount <= 0) {
width.amount = con->width;
}
if (height.amount <= 0) {
height.amount = con->height;
}
if (container_is_floating(con)) {
return resize_set_floating(con, &width, &height);
}
return resize_set_tiled(con, &width, &height);
}
/**
* resize <grow|shrink> <args>
*
* args: <direction>
* args: <direction> <amount> <unit>
* args: <direction> <amount> <unit> or <amount> <other_unit>
*/
static struct cmd_results *cmd_resize_adjust(int argc, char **argv,
int multiplier) {
const char usage[] = "Expected 'resize grow|shrink <direction> "
"[<amount> px|ppt [or <amount> px|ppt]]'";
uint32_t axis = parse_resize_axis(*argv);
if (axis == WLR_EDGE_NONE) {
return cmd_results_new(CMD_INVALID, usage);
}
--argc; ++argv;
// First amount
struct resize_amount first_amount;
if (argc) {
int num_consumed_args = parse_resize_amount(argc, argv, &first_amount);
argc -= num_consumed_args;
argv += num_consumed_args;
if (first_amount.unit == RESIZE_UNIT_INVALID) {
return cmd_results_new(CMD_INVALID, usage);
}
} else {
first_amount.amount = 10;
first_amount.unit = RESIZE_UNIT_DEFAULT;
}
// "or"
if (argc) {
if (strcmp(*argv, "or") != 0) {
return cmd_results_new(CMD_INVALID, usage);
}
--argc; ++argv;
}
// Second amount
struct resize_amount second_amount;
if (argc) {
int num_consumed_args = parse_resize_amount(argc, argv, &second_amount);
if (argc > num_consumed_args) {
return cmd_results_new(CMD_INVALID, usage);
}
if (second_amount.unit == RESIZE_UNIT_INVALID) {
return cmd_results_new(CMD_INVALID, usage);
}
} else {
second_amount.amount = 0;
second_amount.unit = RESIZE_UNIT_INVALID;
}
first_amount.amount *= multiplier;
second_amount.amount *= multiplier;
struct sway_container *con = config->handler_context.container;
if (container_is_floating(con)) {
// Floating containers can only resize in px. Choose an amount which
// uses px, with fallback to an amount that specified no unit.
if (first_amount.unit == RESIZE_UNIT_PX) {
return resize_adjust_floating(axis, &first_amount);
} else if (second_amount.unit == RESIZE_UNIT_PX) {
return resize_adjust_floating(axis, &second_amount);
} else if (first_amount.unit == RESIZE_UNIT_DEFAULT) {
return resize_adjust_floating(axis, &first_amount);
} else if (second_amount.unit == RESIZE_UNIT_DEFAULT) {
return resize_adjust_floating(axis, &second_amount);
} else {
return cmd_results_new(CMD_INVALID,
"Floating containers cannot use ppt measurements");
}
}
// For tiling, prefer ppt -> default -> px
if (first_amount.unit == RESIZE_UNIT_PPT) {
return resize_adjust_tiled(axis, &first_amount);
} else if (second_amount.unit == RESIZE_UNIT_PPT) {
return resize_adjust_tiled(axis, &second_amount);
} else if (first_amount.unit == RESIZE_UNIT_DEFAULT) {
return resize_adjust_tiled(axis, &first_amount);
} else if (second_amount.unit == RESIZE_UNIT_DEFAULT) {
return resize_adjust_tiled(axis, &second_amount);
} else {
return resize_adjust_tiled(axis, &first_amount);
}
}
struct cmd_results *cmd_resize(int argc, char **argv) {
if (!root->outputs->length) {
return cmd_results_new(CMD_INVALID,
"Can't run this command while there's no outputs connected.");
}
struct sway_container *current = config->handler_context.container;
if (!current) {
return cmd_results_new(CMD_INVALID, "Cannot resize nothing");
}
struct cmd_results *error;
if ((error = checkarg(argc, "resize", EXPECTED_AT_LEAST, 2))) {
return error;
}
if (strcasecmp(argv[0], "set") == 0) {
return cmd_resize_set(argc - 1, &argv[1]);
}
if (strcasecmp(argv[0], "grow") == 0) {
return cmd_resize_adjust(argc - 1, &argv[1], 1);
}
if (strcasecmp(argv[0], "shrink") == 0) {
return cmd_resize_adjust(argc - 1, &argv[1], -1);
}
const char usage[] = "Expected 'resize <shrink|grow> "
"<width|height|up|down|left|right> [<amount>] [px|ppt]'";
return cmd_results_new(CMD_INVALID, usage);
}