Split renderer

1 files changed, 893 insertions, 0 deletions

diff --git a/sway/desktop/render.c b/sway/desktop/render.c
new file mode 100644
index 00000000..43948f29
--- /dev/null
+++ b/sway/desktop/render.c
@@ -0,0 +1,893 @@
+#define _POSIX_C_SOURCE 200809L
+#include <assert.h>
+#include <stdlib.h>
+#include <strings.h>
+#include <time.h>
+#include <wayland-server.h>
+#include <wlr/render/wlr_renderer.h>
+#include <wlr/types/wlr_box.h>
+#include <wlr/types/wlr_buffer.h>
+#include <wlr/types/wlr_matrix.h>
+#include <wlr/types/wlr_output_damage.h>
+#include <wlr/types/wlr_output_layout.h>
+#include <wlr/types/wlr_output.h>
+#include <wlr/types/wlr_surface.h>
+#include <wlr/util/region.h>
+#include "log.h"
+#include "sway/config.h"
+#include "sway/input/input-manager.h"
+#include "sway/input/seat.h"
+#include "sway/layers.h"
+#include "sway/output.h"
+#include "sway/server.h"
+#include "sway/tree/arrange.h"
+#include "sway/tree/container.h"
+#include "sway/tree/layout.h"
+#include "sway/tree/view.h"
+#include "sway/tree/workspace.h"
+
+struct render_data {
+        struct root_geometry root_geo;
+        struct sway_output *output;
+        pixman_region32_t *damage;
+        struct sway_view *view;
+        float alpha;
+};
+
+static void scale_box(struct wlr_box *box, float scale) {
+        box->x *= scale;
+        box->y *= scale;
+        box->width *= scale;
+        box->height *= scale;
+}
+
+static void scissor_output(struct wlr_output *wlr_output,
+                pixman_box32_t *rect) {
+        struct wlr_renderer *renderer = wlr_backend_get_renderer(wlr_output->backend);
+        assert(renderer);
+
+        struct wlr_box box = {
+                .x = rect->x1,
+                .y = rect->y1,
+                .width = rect->x2 - rect->x1,
+                .height = rect->y2 - rect->y1,
+        };
+
+        int ow, oh;
+        wlr_output_transformed_resolution(wlr_output, &ow, &oh);
+
+        enum wl_output_transform transform =
+                wlr_output_transform_invert(wlr_output->transform);
+        wlr_box_transform(&box, transform, ow, oh, &box);
+
+        wlr_renderer_scissor(renderer, &box);
+}
+
+static void render_texture(struct wlr_output *wlr_output,
+                pixman_region32_t *output_damage, struct wlr_texture *texture,
+                const struct wlr_box *box, const float matrix[static 9], float alpha) {
+        struct wlr_renderer *renderer =
+                wlr_backend_get_renderer(wlr_output->backend);
+
+        pixman_region32_t damage;
+        pixman_region32_init(&damage);
+        pixman_region32_union_rect(&damage, &damage, box->x, box->y,
+                box->width, box->height);
+        pixman_region32_intersect(&damage, &damage, output_damage);
+        bool damaged = pixman_region32_not_empty(&damage);
+        if (!damaged) {
+                goto damage_finish;
+        }
+
+        int nrects;
+        pixman_box32_t *rects = pixman_region32_rectangles(&damage, &nrects);
+        for (int i = 0; i < nrects; ++i) {
+                scissor_output(wlr_output, &rects[i]);
+                wlr_render_texture_with_matrix(renderer, texture, matrix, alpha);
+        }
+
+damage_finish:
+        pixman_region32_fini(&damage);
+}
+
+static void render_surface_iterator(struct wlr_surface *surface, int sx, int sy,
+                void *_data) {
+        struct render_data *data = _data;
+        struct wlr_output *wlr_output = data->output->wlr_output;
+        float rotation = data->root_geo.rotation;
+        pixman_region32_t *output_damage = data->damage;
+        float alpha = data->alpha;
+
+        struct wlr_texture *texture = wlr_surface_get_texture(surface);
+        if (!texture) {
+                return;
+        }
+
+        struct wlr_box box;
+        bool intersects = output_get_surface_box(&data->root_geo, data->output,
+                surface, sx, sy, &box);
+        if (!intersects) {
+                return;
+        }
+
+        scale_box(&box, wlr_output->scale);
+
+        float matrix[9];
+        enum wl_output_transform transform =
+                wlr_output_transform_invert(surface->current.transform);
+        wlr_matrix_project_box(matrix, &box, transform, rotation,
+                wlr_output->transform_matrix);
+
+        render_texture(wlr_output, output_damage, texture, &box, matrix, alpha);
+}
+
+static void render_layer(struct sway_output *output,
+                pixman_region32_t *damage, struct wl_list *layer_surfaces) {
+        struct render_data data = {
+                .output = output,
+                .damage = damage,
+                .alpha = 1.0f,
+        };
+        output_layer_for_each_surface(layer_surfaces, &data.root_geo,
+                render_surface_iterator, &data);
+}
+
+static void render_unmanaged(struct sway_output *output,
+                pixman_region32_t *damage, struct wl_list *unmanaged) {
+        struct render_data data = {
+                .output = output,
+                .damage = damage,
+                .alpha = 1.0f,
+        };
+        output_unmanaged_for_each_surface(unmanaged, output, &data.root_geo,
+                render_surface_iterator, &data);
+}
+
+static void render_drag_icons(struct sway_output *output,
+                pixman_region32_t *damage, struct wl_list *drag_icons) {
+        struct render_data data = {
+                .output = output,
+                .damage = damage,
+                .alpha = 1.0f,
+        };
+        output_drag_icons_for_each_surface(drag_icons, output, &data.root_geo,
+                render_surface_iterator, &data);
+}
+
+static void render_rect(struct wlr_output *wlr_output,
+                pixman_region32_t *output_damage, const struct wlr_box *_box,
+                float color[static 4]) {
+        struct wlr_renderer *renderer =
+                wlr_backend_get_renderer(wlr_output->backend);
+
+        struct wlr_box box;
+        memcpy(&box, _box, sizeof(struct wlr_box));
+        box.x -= wlr_output->lx * wlr_output->scale;
+        box.y -= wlr_output->ly * wlr_output->scale;
+
+        pixman_region32_t damage;
+        pixman_region32_init(&damage);
+        pixman_region32_union_rect(&damage, &damage, box.x, box.y,
+                box.width, box.height);
+        pixman_region32_intersect(&damage, &damage, output_damage);
+        bool damaged = pixman_region32_not_empty(&damage);
+        if (!damaged) {
+                goto damage_finish;
+        }
+
+        int nrects;
+        pixman_box32_t *rects = pixman_region32_rectangles(&damage, &nrects);
+        for (int i = 0; i < nrects; ++i) {
+                scissor_output(wlr_output, &rects[i]);
+                wlr_render_rect(renderer, &box, color,
+                        wlr_output->transform_matrix);
+        }
+
+damage_finish:
+        pixman_region32_fini(&damage);
+}
+
+static void premultiply_alpha(float color[4], float opacity) {
+        color[3] *= opacity;
+        color[0] *= color[3];
+        color[1] *= color[3];
+        color[2] *= color[3];
+}
+
+static void render_view_surfaces(struct sway_view *view,
+                struct sway_output *output, pixman_region32_t *damage, float alpha) {
+        struct render_data data = {
+                .output = output,
+                .damage = damage,
+                .view = view,
+                .alpha = alpha,
+        };
+        output_view_for_each_surface(view, output, &data.root_geo,
+                render_surface_iterator, &data);
+}
+
+static void render_saved_view(struct sway_view *view,
+                struct sway_output *output, pixman_region32_t *damage, float alpha) {
+        struct wlr_output *wlr_output = output->wlr_output;
+
+        int width, height;
+        struct wlr_texture *texture =
+                transaction_get_saved_texture(view, &width, &height);
+        if (!texture) {
+                return;
+        }
+        struct wlr_box box = {
+                .x = view->swayc->current.view_x - output->swayc->current.swayc_x,
+                .y = view->swayc->current.view_y - output->swayc->current.swayc_y,
+                .width = width,
+                .height = height,
+        };
+
+        struct wlr_box output_box = {
+                .width = output->swayc->current.swayc_width,
+                .height = output->swayc->current.swayc_height,
+        };
+
+        struct wlr_box intersection;
+        bool intersects = wlr_box_intersection(&output_box, &box, &intersection);
+        if (!intersects) {
+                return;
+        }
+
+        scale_box(&box, wlr_output->scale);
+
+        float matrix[9];
+        wlr_matrix_project_box(matrix, &box, WL_OUTPUT_TRANSFORM_NORMAL, 0,
+                wlr_output->transform_matrix);
+
+        render_texture(wlr_output, damage, texture, &box, matrix, alpha);
+}
+
+/**
+ * Render a view's surface and left/bottom/right borders.
+ */
+static void render_view(struct sway_output *output, pixman_region32_t *damage,
+                struct sway_container *con, struct border_colors *colors) {
+        struct sway_view *view = con->sway_view;
+        if (view->swayc->instructions->length) {
+                render_saved_view(view, output, damage, view->swayc->alpha);
+        } else {
+                render_view_surfaces(view, output, damage, view->swayc->alpha);
+        }
+
+        struct wlr_box box;
+        float output_scale = output->wlr_output->scale;
+        float color[4];
+        struct sway_container_state *state = &con->current;
+
+        if (state->border != B_NONE) {
+                if (state->border_left) {
+                        memcpy(&color, colors->child_border, sizeof(float) * 4);
+                        premultiply_alpha(color, con->alpha);
+                        box.x = state->swayc_x;
+                        box.y = state->view_y;
+                        box.width = state->border_thickness;
+                        box.height = state->view_height;
+                        scale_box(&box, output_scale);
+                        render_rect(output->wlr_output, damage, &box, color);
+                }
+
+                if (state->border_right) {
+                        if (state->parent->current.children->length == 1
+                                        && state->parent->current.layout == L_HORIZ) {
+                                memcpy(&color, colors->indicator, sizeof(float) * 4);
+                        } else {
+                                memcpy(&color, colors->child_border, sizeof(float) * 4);
+                        }
+                        premultiply_alpha(color, con->alpha);
+                        box.x = state->view_x + state->view_width;
+                        box.y = state->view_y;
+                        box.width = state->border_thickness;
+                        box.height = state->view_height;
+                        scale_box(&box, output_scale);
+                        render_rect(output->wlr_output, damage, &box, color);
+                }
+
+                if (state->border_bottom) {
+                        if (state->parent->current.children->length == 1
+                                        && con->current.parent->current.layout == L_VERT) {
+                                memcpy(&color, colors->indicator, sizeof(float) * 4);
+                        } else {
+                                memcpy(&color, colors->child_border, sizeof(float) * 4);
+                        }
+                        premultiply_alpha(color, con->alpha);
+                        box.x = state->swayc_x;
+                        box.y = state->view_y + state->view_height;
+                        box.width = state->swayc_width;
+                        box.height = state->border_thickness;
+                        scale_box(&box, output_scale);
+                        render_rect(output->wlr_output, damage, &box, color);
+                }
+        }
+}
+
+/**
+ * Render a titlebar.
+ *
+ * Care must be taken not to render over the same pixel multiple times,
+ * otherwise the colors will be incorrect when using opacity.
+ *
+ * The height is: 1px border, 3px padding, font height, 3px padding, 1px border
+ * The left side for L_TABBED is: 1px border, 2px padding, title
+ * The left side for other layouts is: 3px padding, title
+ */
+static void render_titlebar(struct sway_output *output,
+                pixman_region32_t *output_damage, struct sway_container *con,
+                int x, int y, int width,
+                struct border_colors *colors, struct wlr_texture *title_texture,
+                struct wlr_texture *marks_texture) {
+        struct wlr_box box;
+        float color[4];
+        struct sway_container_state *state = &con->current;
+        float output_scale = output->wlr_output->scale;
+        enum sway_container_layout layout = state->parent->current.layout;
+        list_t *children = state->parent->current.children;
+        bool is_last_child = children->items[children->length - 1] == con;
+        double output_x = output->swayc->current.swayc_x;
+        double output_y = output->swayc->current.swayc_y;
+
+        // Single pixel bar above title
+        memcpy(&color, colors->border, sizeof(float) * 4);
+        premultiply_alpha(color, con->alpha);
+        box.x = x;
+        box.y = y;
+        box.width = width;
+        box.height = TITLEBAR_BORDER_THICKNESS;
+        scale_box(&box, output_scale);
+        render_rect(output->wlr_output, output_damage, &box, color);
+
+        // Single pixel bar below title
+        size_t left_offset = 0, right_offset = 0;
+        bool connects_sides = false;
+        if (layout == L_HORIZ || layout == L_VERT ||
+                        (layout == L_STACKED && is_last_child)) {
+                if (con->type == C_VIEW) {
+                        left_offset = state->border_left * state->border_thickness;
+                        right_offset = state->border_right * state->border_thickness;
+                        connects_sides = true;
+                }
+        }
+        box.x = x + left_offset;
+        box.y = y + container_titlebar_height() - TITLEBAR_BORDER_THICKNESS;
+        box.width = width - left_offset - right_offset;
+        box.height = TITLEBAR_BORDER_THICKNESS;
+        scale_box(&box, output_scale);
+        render_rect(output->wlr_output, output_damage, &box, color);
+
+        if (layout == L_TABBED) {
+                // Single pixel left edge
+                box.x = x;
+                box.y = y + TITLEBAR_BORDER_THICKNESS;
+                box.width = TITLEBAR_BORDER_THICKNESS;
+                box.height =
+                        container_titlebar_height() - TITLEBAR_BORDER_THICKNESS * 2;
+                scale_box(&box, output_scale);
+                render_rect(output->wlr_output, output_damage, &box, color);
+
+                // Single pixel right edge
+                box.x = (x + width - TITLEBAR_BORDER_THICKNESS) * output_scale;
+                render_rect(output->wlr_output, output_damage, &box, color);
+        }
+
+        size_t inner_width = width - TITLEBAR_H_PADDING * 2;
+
+        // Marks
+        size_t marks_ob_width = 0; // output-buffer-local
+        if (config->show_marks && marks_texture) {
+                struct wlr_box texture_box;
+                wlr_texture_get_size(marks_texture,
+                        &texture_box.width, &texture_box.height);
+                texture_box.x = (x - output_x + width - TITLEBAR_H_PADDING)
+                        * output_scale - texture_box.width;
+                texture_box.y = (y - output_y + TITLEBAR_V_PADDING) * output_scale;
+
+                float matrix[9];
+                wlr_matrix_project_box(matrix, &texture_box,
+                        WL_OUTPUT_TRANSFORM_NORMAL,
+                        0.0, output->wlr_output->transform_matrix);
+
+                if (inner_width * output_scale < texture_box.width) {
+                        texture_box.width = inner_width * output_scale;
+                }
+                render_texture(output->wlr_output, output_damage, marks_texture,
+                        &texture_box, matrix, con->alpha);
+                marks_ob_width = texture_box.width;
+
+                // Gap between the marks and bottom padding, for when the marks texture
+                // height is smaller than the config's font height
+                memcpy(&color, colors->background, sizeof(float) * 4);
+                premultiply_alpha(color, con->alpha);
+                box.x = texture_box.x;
+                box.y = texture_box.y + texture_box.height;
+                box.width = texture_box.width;
+                box.height = config->font_height * output_scale - texture_box.height;
+                if (box.height > 0) {
+                        render_rect(output->wlr_output, output_damage, &box, color);
+                }
+        }
+
+        // Title text
+        size_t title_ob_width = 0; // output-buffer-local
+        if (title_texture) {
+                struct wlr_box texture_box;
+                wlr_texture_get_size(title_texture,
+                        &texture_box.width, &texture_box.height);
+                texture_box.x = (x - output_x + TITLEBAR_H_PADDING) * output_scale;
+                texture_box.y = (y - output_y + TITLEBAR_V_PADDING) * output_scale;
+
+                float matrix[9];
+                wlr_matrix_project_box(matrix, &texture_box,
+                        WL_OUTPUT_TRANSFORM_NORMAL,
+                        0.0, output->wlr_output->transform_matrix);
+
+                if (inner_width * output_scale - marks_ob_width < texture_box.width) {
+                        texture_box.width = inner_width * output_scale - marks_ob_width;
+                }
+                render_texture(output->wlr_output, output_damage, title_texture,
+                        &texture_box, matrix, con->alpha);
+                title_ob_width = texture_box.width;
+
+                // Gap between the title and bottom padding, for when the title texture
+                // height is smaller than the config's font height
+                memcpy(&color, colors->background, sizeof(float) * 4);
+                premultiply_alpha(color, con->alpha);
+                box.x = texture_box.x;
+                box.y = texture_box.y + texture_box.height;
+                box.width = texture_box.width;
+                box.height = config->font_height * output_scale - texture_box.height;
+                if (box.height > 0) {
+                        render_rect(output->wlr_output, output_damage, &box, color);
+                }
+        }
+
+        // Padding above title
+        memcpy(&color, colors->background, sizeof(float) * 4);
+        premultiply_alpha(color, con->alpha);
+        box.x = x + (layout == L_TABBED) * TITLEBAR_BORDER_THICKNESS;
+        box.y = y + TITLEBAR_BORDER_THICKNESS;
+        box.width = width - (layout == L_TABBED) * TITLEBAR_BORDER_THICKNESS * 2;
+        box.height = TITLEBAR_V_PADDING - TITLEBAR_BORDER_THICKNESS;
+        scale_box(&box, output_scale);
+        render_rect(output->wlr_output, output_damage, &box, color);
+
+        // Padding below title
+        box.y = (y + TITLEBAR_V_PADDING + config->font_height) * output_scale;
+        render_rect(output->wlr_output, output_damage, &box, color);
+
+        // Filler between title and marks
+        box.width = inner_width * output_scale - title_ob_width - marks_ob_width;
+        if (box.width > 0) {
+                box.x = (x + TITLEBAR_H_PADDING) * output_scale + title_ob_width;
+                box.y = (y + TITLEBAR_V_PADDING) * output_scale;
+                box.height = config->font_height * output_scale;
+                render_rect(output->wlr_output, output_damage, &box, color);
+        }
+
+        // Padding left of title
+        left_offset = (layout == L_TABBED) * TITLEBAR_BORDER_THICKNESS;
+        box.x = x + left_offset;
+        box.y = y + TITLEBAR_V_PADDING;
+        box.width = TITLEBAR_H_PADDING - left_offset;
+        box.height = config->font_height;
+        scale_box(&box, output_scale);
+        render_rect(output->wlr_output, output_damage, &box, color);
+
+        // Padding right of marks
+        right_offset = (layout == L_TABBED) * TITLEBAR_BORDER_THICKNESS;
+        box.x = x + width - TITLEBAR_H_PADDING;
+        box.y = y + TITLEBAR_V_PADDING;
+        box.width = TITLEBAR_H_PADDING - right_offset;
+        box.height = config->font_height;
+        scale_box(&box, output_scale);
+        render_rect(output->wlr_output, output_damage, &box, color);
+
+        if (connects_sides) {
+                // Left pixel in line with bottom bar
+                box.x = x;
+                box.y = y + container_titlebar_height() - TITLEBAR_BORDER_THICKNESS;
+                box.width = state->border_thickness * state->border_left;
+                box.height = TITLEBAR_BORDER_THICKNESS;
+                scale_box(&box, output_scale);
+                render_rect(output->wlr_output, output_damage, &box, color);
+
+                // Right pixel in line with bottom bar
+                box.x = x + width - state->border_thickness * state->border_right;
+                box.y = y + container_titlebar_height() - TITLEBAR_BORDER_THICKNESS;
+                box.width = state->border_thickness * state->border_right;
+                box.height = TITLEBAR_BORDER_THICKNESS;
+                scale_box(&box, output_scale);
+                render_rect(output->wlr_output, output_damage, &box, color);
+        }
+}
+
+/**
+ * Render the top border line for a view using "border pixel".
+ */
+static void render_top_border(struct sway_output *output,
+                pixman_region32_t *output_damage, struct sway_container *con,
+                struct border_colors *colors) {
+        struct sway_container_state *state = &con->current;
+        if (!state->border_top) {
+                return;
+        }
+        struct wlr_box box;
+        float color[4];
+        float output_scale = output->wlr_output->scale;
+
+        // Child border - top edge
+        memcpy(&color, colors->child_border, sizeof(float) * 4);
+        premultiply_alpha(color, con->alpha);
+        box.x = state->swayc_x;
+        box.y = state->swayc_y;
+        box.width = state->swayc_width;
+        box.height = state->border_thickness;
+        scale_box(&box, output_scale);
+        render_rect(output->wlr_output, output_damage, &box, color);
+}
+
+static void render_container(struct sway_output *output,
+        pixman_region32_t *damage, struct sway_container *con, bool parent_focused);
+
+/**
+ * Render a container's children using a L_HORIZ or L_VERT layout.
+ *
+ * Wrap child views in borders and leave child containers borderless because
+ * they'll apply their own borders to their children.
+ */
+static void render_container_simple(struct sway_output *output,
+                pixman_region32_t *damage, struct sway_container *con,
+                bool parent_focused) {
+        struct sway_seat *seat = input_manager_current_seat(input_manager);
+        struct sway_container *focus = seat_get_focus(seat);
+
+        for (int i = 0; i < con->current.children->length; ++i) {
+                struct sway_container *child = con->current.children->items[i];
+
+                if (child->type == C_VIEW) {
+                        struct sway_view *view = child->sway_view;
+                        struct border_colors *colors;
+                        struct wlr_texture *title_texture;
+                        struct wlr_texture *marks_texture;
+                        struct sway_container_state *state = &child->current;
+
+                        if (focus == child || parent_focused) {
+                                colors = &config->border_colors.focused;
+                                title_texture = child->title_focused;
+                                marks_texture = view->marks_focused;
+                        } else if (seat_get_focus_inactive(seat, con) == child) {
+                                colors = &config->border_colors.focused_inactive;
+                                title_texture = child->title_focused_inactive;
+                                marks_texture = view->marks_focused_inactive;
+                        } else {
+                                colors = &config->border_colors.unfocused;
+                                title_texture = child->title_unfocused;
+                                marks_texture = view->marks_unfocused;
+                        }
+
+                        if (state->border == B_NORMAL) {
+                                render_titlebar(output, damage, child, state->swayc_x,
+                                                state->swayc_y, state->swayc_width, colors,
+                                                title_texture, marks_texture);
+                        } else {
+                                render_top_border(output, damage, child, colors);
+                        }
+                        render_view(output, damage, child, colors);
+                } else {
+                        render_container(output, damage, child,
+                                        parent_focused || focus == child);
+                }
+        }
+}
+
+/**
+ * Render a container's children using the L_TABBED layout.
+ */
+static void render_container_tabbed(struct sway_output *output,
+                pixman_region32_t *damage, struct sway_container *con,
+                bool parent_focused) {
+        if (!con->current.children->length) {
+                return;
+        }
+        struct sway_seat *seat = input_manager_current_seat(input_manager);
+        struct sway_container *focus = seat_get_focus(seat);
+        struct sway_container *current = seat_get_active_current_child(seat, con);
+        struct border_colors *current_colors = &config->border_colors.unfocused;
+        struct sway_container_state *pstate = &con->current;
+
+        // Render tabs
+        for (int i = 0; i < con->current.children->length; ++i) {
+                struct sway_container *child = con->current.children->items[i];
+                struct sway_view *view = child->type == C_VIEW ? child->sway_view : NULL;
+                struct sway_container_state *cstate = &child->current;
+                struct border_colors *colors;
+                struct wlr_texture *title_texture;
+                struct wlr_texture *marks_texture;
+
+                if (focus == child || parent_focused) {
+                        colors = &config->border_colors.focused;
+                        title_texture = child->title_focused;
+                        marks_texture = view ? view->marks_focused : NULL;
+                } else if (child == current) {
+                        colors = &config->border_colors.focused_inactive;
+                        title_texture = child->title_focused_inactive;
+                        marks_texture = view ? view->marks_focused_inactive : NULL;
+                } else {
+                        colors = &config->border_colors.unfocused;
+                        title_texture = child->title_unfocused;
+                        marks_texture = view ? view->marks_unfocused : NULL;
+                }
+
+                int tab_width = pstate->swayc_width / pstate->children->length;
+                int x = pstate->swayc_x + tab_width * i;
+                // Make last tab use the remaining width of the parent
+                if (i == pstate->children->length - 1) {
+                        tab_width = pstate->swayc_width - tab_width * i;
+                }
+
+                render_titlebar(output, damage, child, x, cstate->swayc_y, tab_width,
+                                colors, title_texture, marks_texture);
+
+                if (child == current) {
+                        current_colors = colors;
+                }
+        }
+
+        // Render surface and left/right/bottom borders
+        if (current) {
+                if (current->type == C_VIEW) {
+                        render_view(output, damage, current, current_colors);
+                } else {
+                        render_container(output, damage, current,
+                                        parent_focused || current == focus);
+                }
+        }
+}
+
+/**
+ * Render a container's children using the L_STACKED layout.
+ */
+static void render_container_stacked(struct sway_output *output,
+                pixman_region32_t *damage, struct sway_container *con,
+                bool parent_focused) {
+        if (!con->current.children->length) {
+                return;
+        }
+        struct sway_seat *seat = input_manager_current_seat(input_manager);
+        struct sway_container *focus = seat_get_focus(seat);
+        struct sway_container *current = seat_get_active_current_child(seat, con);
+        struct border_colors *current_colors = &config->border_colors.unfocused;
+        struct sway_container_state *pstate = &con->current;
+
+        // Render titles
+        for (int i = 0; i < con->current.children->length; ++i) {
+                struct sway_container *child = con->current.children->items[i];
+                struct sway_view *view = child->type == C_VIEW ? child->sway_view : NULL;
+                struct sway_container_state *cstate = &child->current;
+                struct border_colors *colors;
+                struct wlr_texture *title_texture;
+                struct wlr_texture *marks_texture;
+
+                if (focus == child || parent_focused) {
+                        colors = &config->border_colors.focused;
+                        title_texture = child->title_focused;
+                        marks_texture = view ? view->marks_focused : NULL;
+                } else if (child == current) {
+                        colors = &config->border_colors.focused_inactive;
+                        title_texture = child->title_focused_inactive;
+                        marks_texture = view ? view->marks_focused_inactive : NULL;
+                } else {
+                        colors = &config->border_colors.unfocused;
+                        title_texture = child->title_unfocused;
+                        marks_texture = view ? view->marks_unfocused : NULL;
+                }
+
+                int y = pstate->swayc_y + container_titlebar_height() * i;
+                render_titlebar(output, damage, child, cstate->swayc_x, y,
+                                cstate->swayc_width, colors, title_texture, marks_texture);
+
+                if (child == current) {
+                        current_colors = colors;
+                }
+        }
+
+        // Render surface and left/right/bottom borders
+        if (current) {
+                if (current->type == C_VIEW) {
+                        render_view(output, damage, current, current_colors);
+                } else {
+                        render_container(output, damage, current,
+                                        parent_focused || current == focus);
+                }
+        }
+}
+
+static void render_container(struct sway_output *output,
+                pixman_region32_t *damage, struct sway_container *con,
+                bool parent_focused) {
+        switch (con->current.layout) {
+        case L_NONE:
+        case L_HORIZ:
+        case L_VERT:
+                render_container_simple(output, damage, con, parent_focused);
+                break;
+        case L_STACKED:
+                render_container_stacked(output, damage, con, parent_focused);
+                break;
+        case L_TABBED:
+                render_container_tabbed(output, damage, con, parent_focused);
+                break;
+        case L_FLOATING:
+                sway_assert(false, "Didn't expect to see floating here");
+        }
+}
+
+static void render_floating_container(struct sway_output *soutput,
+                pixman_region32_t *damage, struct sway_container *con) {
+        if (con->type == C_VIEW) {
+                struct sway_view *view = con->sway_view;
+                struct sway_seat *seat = input_manager_current_seat(input_manager);
+                struct sway_container *focus = seat_get_focus(seat);
+                struct border_colors *colors;
+                struct wlr_texture *title_texture;
+                struct wlr_texture *marks_texture;
+
+                if (focus == con) {
+                        colors = &config->border_colors.focused;
+                        title_texture = con->title_focused;
+                        marks_texture = view->marks_focused;
+                } else {
+                        colors = &config->border_colors.unfocused;
+                        title_texture = con->title_unfocused;
+                        marks_texture = view->marks_unfocused;
+                }
+
+                if (con->current.border == B_NORMAL) {
+                        render_titlebar(soutput, damage, con, con->current.swayc_x,
+                                        con->current.swayc_y, con->current.swayc_width, colors,
+                                        title_texture, marks_texture);
+                } else if (con->current.border != B_NONE) {
+                        render_top_border(soutput, damage, con, colors);
+                }
+                render_view(soutput, damage, con, colors);
+        } else {
+                render_container(soutput, damage, con, false);
+        }
+}
+
+static void render_floating(struct sway_output *soutput,
+                pixman_region32_t *damage) {
+        for (int i = 0; i < root_container.current.children->length; ++i) {
+                struct sway_container *output =
+                        root_container.current.children->items[i];
+                for (int j = 0; j < output->current.children->length; ++j) {
+                        struct sway_container *ws = output->current.children->items[j];
+                        if (!workspace_is_visible(ws)) {
+                                continue;
+                        }
+                        list_t *floating =
+                                ws->current.ws_floating->current.children;
+                        for (int k = 0; k < floating->length; ++k) {
+                                struct sway_container *floater = floating->items[k];
+                                render_floating_container(soutput, damage, floater);
+                        }
+                }
+        }
+}
+
+void output_render(struct sway_output *output, struct timespec *when,
+                pixman_region32_t *damage) {
+        struct wlr_output *wlr_output = output->wlr_output;
+
+        struct wlr_renderer *renderer =
+        wlr_backend_get_renderer(wlr_output->backend);
+        if (!sway_assert(renderer != NULL,
+                        "expected the output backend to have a renderer")) {
+                return;
+        }
+
+        wlr_renderer_begin(renderer, wlr_output->width, wlr_output->height);
+
+        bool damage_whole_before_swap = false;
+        if (!pixman_region32_not_empty(damage)) {
+                // Output isn't damaged but needs buffer swap
+                goto renderer_end;
+        }
+
+        const char *damage_debug = getenv("SWAY_DAMAGE_DEBUG");
+        if (damage_debug != NULL) {
+                if (strcmp(damage_debug, "highlight") == 0) {
+                        wlr_renderer_clear(renderer, (float[]){1, 1, 0, 1});
+                        damage_whole_before_swap = true;
+                } else if (strcmp(damage_debug, "rerender") == 0) {
+                        int width, height;
+                        wlr_output_transformed_resolution(wlr_output, &width, &height);
+                        pixman_region32_union_rect(damage, damage, 0, 0, width, height);
+                }
+        }
+
+        struct sway_container *workspace = output_get_active_workspace(output);
+        struct sway_view *fullscreen_view = workspace->current.ws_fullscreen;
+        struct sway_seat *seat = input_manager_current_seat(input_manager);
+
+        if (output_has_opaque_lockscreen(output, seat)) {
+                struct wlr_layer_surface *wlr_layer_surface = seat->focused_layer;
+                struct sway_layer_surface *sway_layer_surface =
+                        layer_from_wlr_layer_surface(seat->focused_layer);
+                struct render_data data = {
+                        .output = output,
+                        .damage = damage,
+                        .alpha = 1.0f,
+                };
+                output_surface_for_each_surface(wlr_layer_surface->surface,
+                        sway_layer_surface->geo.x, sway_layer_surface->geo.y,
+                        &data.root_geo, render_surface_iterator, &data);
+        } else if (fullscreen_view) {
+                float clear_color[] = {0.0f, 0.0f, 0.0f, 1.0f};
+
+                int nrects;
+                pixman_box32_t *rects = pixman_region32_rectangles(damage, &nrects);
+                for (int i = 0; i < nrects; ++i) {
+                        scissor_output(wlr_output, &rects[i]);
+                        wlr_renderer_clear(renderer, clear_color);
+                }
+
+                // TODO: handle views smaller than the output
+                render_view_surfaces(fullscreen_view, output, damage, 1.0f);
+
+                if (fullscreen_view->type == SWAY_VIEW_XWAYLAND) {
+                        render_unmanaged(output, damage,
+                                &root_container.sway_root->xwayland_unmanaged);
+                }
+        } else {
+                float clear_color[] = {0.25f, 0.25f, 0.25f, 1.0f};
+
+                int nrects;
+                pixman_box32_t *rects = pixman_region32_rectangles(damage, &nrects);
+                for (int i = 0; i < nrects; ++i) {
+                        scissor_output(wlr_output, &rects[i]);
+                        wlr_renderer_clear(renderer, clear_color);
+                }
+
+                render_layer(output, damage,
+                        &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BACKGROUND]);
+                render_layer(output, damage,
+                        &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM]);
+
+                struct sway_seat *seat = input_manager_current_seat(input_manager);
+                struct sway_container *focus = seat_get_focus(seat);
+                render_container(output, damage, workspace, focus == workspace);
+                render_floating(output, damage);
+
+                render_unmanaged(output, damage,
+                        &root_container.sway_root->xwayland_unmanaged);
+                render_layer(output, damage,
+                        &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_TOP]);
+        }
+        render_layer(output, damage,
+                &output->layers[ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY]);
+        render_drag_icons(output, damage, &root_container.sway_root->drag_icons);
+
+renderer_end:
+        if (root_container.sway_root->debug_tree) {
+                wlr_render_texture(renderer, root_container.sway_root->debug_tree,
+                        wlr_output->transform_matrix, 0, 0, 1);
+        }
+
+        if (damage_whole_before_swap || root_container.sway_root->debug_tree) {
+                int width, height;
+                wlr_output_transformed_resolution(wlr_output, &width, &height);
+                pixman_region32_union_rect(damage, damage, 0, 0, width, height);
+        }
+
+        wlr_renderer_scissor(renderer, NULL);
+        wlr_renderer_end(renderer);
+        if (!wlr_output_damage_swap_buffers(output->damage, when, damage)) {
+                return;
+        }
+        output->last_frame = *when;
+}