Refactor arrange_windows()

Replaces arrange_windows() with arrange_root(), arrange_output(),
arrange_workspace() and arrange_children_of().

Also makes fullscreen views save and restore their dimensions, which
allows it to preserve any custom resize and is also a requirement for
floating views once they are implemented.

1 files changed, 239 insertions, 0 deletions

diff --git a/sway/tree/arrange.c b/sway/tree/arrange.c
new file mode 100644
index 00000000..dd87ce7c
--- /dev/null
+++ b/sway/tree/arrange.c
@@ -0,0 +1,239 @@
+#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/debug.h"
+#include "sway/tree/arrange.h"
+#include "sway/tree/container.h"
+#include "sway/tree/layout.h"
+#include "sway/output.h"
+#include "sway/tree/workspace.h"
+#include "sway/tree/view.h"
+#include "list.h"
+#include "log.h"
+
+struct sway_container root_container;
+
+void arrange_windows(struct sway_container *container) {
+        switch (container->type) {
+        case C_ROOT:
+                arrange_root();
+                break;
+        case C_OUTPUT:
+                arrange_output(container);
+                break;
+        case C_WORKSPACE:
+                arrange_workspace(container);
+                break;
+        case C_CONTAINER:
+                arrange_children_of(container);
+                break;
+        case C_VIEW:
+                // ignore
+                break;
+        case C_TYPES:
+                sway_assert(
+                                false, "Called arrange_windows() with container type C_TYPES");
+                break;
+        }
+}
+
+void arrange_root() {
+        if (config->reloading) {
+                return;
+        }
+        struct wlr_output_layout *output_layout =
+                root_container.sway_root->output_layout;
+        const struct wlr_box *layout_box =
+                wlr_output_layout_get_box(output_layout, NULL);
+        root_container.x = layout_box->x;
+        root_container.y = layout_box->y;
+        root_container.width = layout_box->width;
+        root_container.height = layout_box->height;
+        for (int i = 0; i < root_container.children->length; ++i) {
+                struct sway_container *output = root_container.children->items[i];
+                arrange_output(output);
+        }
+}
+
+void arrange_output(struct sway_container *output) {
+        if (config->reloading) {
+                return;
+        }
+        if (!sway_assert(output->type == C_OUTPUT,
+                        "called arrange_output() on non-output container")) {
+                return;
+        }
+        const struct wlr_box *output_box = wlr_output_layout_get_box(
+                        root_container.sway_root->output_layout,
+                        output->sway_output->wlr_output);
+        output->x = output_box->x;
+        output->y = output_box->y;
+        output->width = output_box->width;
+        output->height = output_box->height;
+        wlr_log(L_DEBUG, "Arranging output '%s' at %f,%f",
+                        output->name, output->x, output->y);
+        for (int i = 0; i < output->children->length; ++i) {
+                struct sway_container *workspace = output->children->items[i];
+                arrange_workspace(workspace);
+        }
+        container_damage_whole(output);
+}
+
+void arrange_workspace(struct sway_container *workspace) {
+        if (config->reloading) {
+                return;
+        }
+        if (!sway_assert(workspace->type == C_WORKSPACE,
+                        "called arrange_workspace() on non-workspace container")) {
+                return;
+        }
+        struct sway_container *output = workspace->parent;
+        struct wlr_box *area = &output->sway_output->usable_area;
+        wlr_log(L_DEBUG, "Usable area for ws: %dx%d@%d,%d",
+                        area->width, area->height, area->x, area->y);
+        workspace->width = area->width;
+        workspace->height = area->height;
+        workspace->x = area->x;
+        workspace->y = area->y;
+        wlr_log(L_DEBUG, "Arranging workspace '%s' at %f, %f",
+                        workspace->name, workspace->x, workspace->y);
+        arrange_children_of(workspace);
+        container_damage_whole(workspace);
+}
+
+static void apply_horiz_layout(struct sway_container *parent) {
+        size_t num_children = parent->children->length;
+        if (!num_children) {
+                return;
+        }
+        // Calculate total width of children
+        double total_width = 0;
+        for (size_t i = 0; i < num_children; ++i) {
+                struct sway_container *child = parent->children->items[i];
+                if (child->width <= 0) {
+                        if (num_children > 1) {
+                                child->width = parent->width / (num_children - 1);
+                        } else {
+                                child->width = parent->width;
+                        }
+                }
+                total_width += child->width;
+        }
+        double scale = parent->width / total_width;
+
+        // Resize windows
+        wlr_log(L_DEBUG, "Arranging %p horizontally", parent);
+        double child_x = parent->x;
+        struct sway_container *child;
+        for (size_t i = 0; i < num_children; ++i) {
+                child = parent->children->items[i];
+                wlr_log(L_DEBUG,
+                                "Calculating arrangement for %p:%d (will scale %f by %f)",
+                                child, child->type, child->width, scale);
+                child->x = child_x;
+                child->y = parent->y;
+                child->width = floor(child->width * scale);
+                child->height = parent->height;
+                child_x += child->width;
+        }
+        // Make last child use remaining width of parent
+        child->width = parent->x + parent->width - child->x;
+}
+
+static void apply_vert_layout(struct sway_container *parent) {
+        size_t num_children = parent->children->length;
+        if (!num_children) {
+                return;
+        }
+        // Calculate total height of children
+        double total_height = 0;
+        for (size_t i = 0; i < num_children; ++i) {
+                struct sway_container *child = parent->children->items[i];
+                if (child->height <= 0) {
+                        if (num_children > 1) {
+                                child->height = parent->height / (num_children - 1);
+                        } else {
+                                child->height = parent->height;
+                        }
+                }
+                total_height += child->height;
+        }
+        double scale = parent->height / total_height;
+
+        // Resize
+        wlr_log(L_DEBUG, "Arranging %p vertically", parent);
+        double child_y = parent->y;
+        struct sway_container *child;
+        for (size_t i = 0; i < num_children; ++i) {
+                child = parent->children->items[i];
+                wlr_log(L_DEBUG,
+                                "Calculating arrangement for %p:%d (will scale %f by %f)",
+                                child, child->type, child->height, scale);
+                child->x = parent->x;
+                child->y = child_y;
+                child->width = parent->width;
+                child->height = floor(child->height * scale);
+                child_y += child->height;
+        }
+        // Make last child use remaining height of parent
+        child->height = parent->y + parent->height - child->y;
+}
+
+void arrange_children_of(struct sway_container *parent) {
+        if (config->reloading) {
+                return;
+        }
+        if (!sway_assert(parent->type == C_WORKSPACE || parent->type == C_CONTAINER,
+                        "container is a %s", container_type_to_str(parent->type))) {
+                return;
+        }
+
+        struct sway_container *workspace = parent;
+        if (workspace->type != C_WORKSPACE) {
+                workspace = container_parent(workspace, C_WORKSPACE);
+        }
+        if (workspace->sway_workspace->fullscreen) {
+                // Just arrange the fullscreen view and jump out
+                struct sway_container *view =
+                        workspace->sway_workspace->fullscreen->swayc;
+                view_configure(view->sway_view, 0, 0,
+                                workspace->parent->width, workspace->parent->height);
+                view->width = workspace->parent->width;
+                view->height = workspace->parent->height;
+                return;
+        }
+
+        wlr_log(L_DEBUG, "Arranging layout for %p %s %fx%f+%f,%f", parent,
+                parent->name, parent->width, parent->height, parent->x, parent->y);
+
+        // Calculate x, y, width and height of children
+        switch (parent->layout) {
+        case L_HORIZ:
+                apply_horiz_layout(parent);
+                break;
+        case L_VERT:
+                apply_vert_layout(parent);
+                break;
+        default:
+                wlr_log(L_DEBUG, "TODO: arrange layout type %d", parent->layout);
+                apply_horiz_layout(parent);
+                break;
+        }
+
+        // Apply x, y, width and height to children and recurse if needed
+        for (int i = 0; i < parent->children->length; ++i) {
+                struct sway_container *child = parent->children->items[i];
+                if (child->type == C_VIEW) {
+                        view_configure(child->sway_view, child->x, child->y,
+                                        child->width, child->height);
+                } else {
+                        arrange_children_of(child);
+                }
+        }
+        container_damage_whole(parent);
+        update_debug_tree();
+}