Add scaled_rect_buffer

scaled_rect_buffer is an implementation of scaled_scene_buffer and shows
an auto-scaling bordered rectangle. This is intended for menu borders,
but can be also useful for other elements like window switcher items.

We will support rounded corners for scaled_rect_buffer in the future.

diff --git a/include/common/scaled-rect-buffer.h b/include/common/scaled-rect-buffer.h
new file mode 100644 (file)
index 0000000..4705982
--- /dev/null
+++ b/include/common/scaled-rect-buffer.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef LABWC_SCALED_RECT_BUFFER_H
+#define LABWC_SCALED_RECT_BUFFER_H
+
+#include <stdint.h>
+
+struct wlr_scene_tree;
+struct wlr_scene_buffer;
+struct scaled_scene_buffer;
+
+struct scaled_rect_buffer {
+       struct wlr_scene_buffer *scene_buffer;
+       struct scaled_scene_buffer *scaled_buffer;
+       int width;
+       int height;
+       int border_width;
+       float fill_color[4];
+       float border_color[4];
+};
+
+/*
+ * Create an auto scaling borderd-rectangle buffer, providing a wlr_scene_buffer
+ * node for display. It gets destroyed automatically when the backing
+ * scaled_scene_buffer is being destroyed which in turn happens automatically
+ * when the backing wlr_scene_buffer (or one of its parents) is being destroyed.
+ */
+struct scaled_rect_buffer *scaled_rect_buffer_create(
+       struct wlr_scene_tree *parent, int width, int height, int border_width,
+       float fill_color[4], float border_color[4]);
+
+#endif /* LABWC_SCALED_RECT_BUFFER_H */

diff --git a/src/common/meson.build b/src/common/meson.build
index d369df4ca181b97d34ef04d1a837f3255dee8cea..d6ad2c64e6cbfec0c155bc1a1761838647901457 100644 (file)
--- a/src/common/meson.build
+++ b/src/common/meson.build
@@ -14,6 +14,7 @@ labwc_sources += files(
   'parse-bool.c',
   'parse-double.c',
   'scaled-font-buffer.c',
+  'scaled-rect-buffer.c',
   'scaled-scene-buffer.c',
   'scene-helpers.c',
   'set.c',

diff --git a/src/common/scaled-rect-buffer.c b/src/common/scaled-rect-buffer.c
new file mode 100644 (file)
index 0000000..43a8156
--- /dev/null
+++ b/src/common/scaled-rect-buffer.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#define _POSIX_C_SOURCE 200809L
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <wayland-server-core.h>
+#include <wlr/util/log.h>
+#include "buffer.h"
+#include "common/graphic-helpers.h"
+#include "common/list.h"
+#include "common/macros.h"
+#include "common/mem.h"
+#include "common/scaled-scene-buffer.h"
+#include "common/scaled-rect-buffer.h"
+
+static struct wl_list cached_buffers = WL_LIST_INIT(&cached_buffers);
+
+static void
+draw_rectangle_path(cairo_t *cairo, int width, int height, int border_width)
+{
+       double offset = border_width / 2.0;
+       double right_x = width - offset;
+       double bottom_y = height - offset;
+
+       cairo_move_to(cairo, offset, offset);
+       cairo_line_to(cairo, right_x, offset);
+       cairo_line_to(cairo, right_x, bottom_y);
+       cairo_line_to(cairo, offset, bottom_y);
+       cairo_close_path(cairo);
+}
+
+static struct lab_data_buffer *
+_create_buffer(struct scaled_scene_buffer *scaled_buffer, double scale)
+{
+       struct scaled_rect_buffer *self = scaled_buffer->data;
+       struct lab_data_buffer *buffer = buffer_create_cairo(
+               self->width, self->height, scale);
+       if (!buffer) {
+               return NULL;
+       }
+
+       cairo_t *cairo = buffer->cairo;
+
+       /* Clear background */
+       cairo_set_operator(cairo, CAIRO_OPERATOR_CLEAR);
+       cairo_paint(cairo);
+       cairo_set_operator(cairo, CAIRO_OPERATOR_SOURCE);
+
+       /* Fill rectangle */
+       draw_rectangle_path(cairo, self->width, self->height, 0);
+       set_cairo_color(cairo, self->fill_color);
+       cairo_fill(cairo);
+
+       /* Draw borders */
+       draw_rectangle_path(cairo, self->width, self->height,
+               self->border_width);
+       cairo_set_line_width(cairo, self->border_width);
+       set_cairo_color(cairo, self->border_color);
+       cairo_stroke(cairo);
+
+       return buffer;
+}
+
+static void
+_destroy(struct scaled_scene_buffer *scaled_buffer)
+{
+       struct scaled_rect_buffer *self = scaled_buffer->data;
+       scaled_buffer->data = NULL;
+       free(self);
+}
+
+static bool
+_equal(struct scaled_scene_buffer *scaled_buffer_a, struct scaled_scene_buffer *scaled_buffer_b)
+{
+       struct scaled_rect_buffer *a = scaled_buffer_a->data;
+       struct scaled_rect_buffer *b = scaled_buffer_b->data;
+
+       return a->width == b->width
+               && a->height == b->height
+               && a->border_width == b->border_width
+               && !memcmp(a->fill_color, b->fill_color, sizeof(a->fill_color))
+               && !memcmp(a->border_color, b->border_color, sizeof(a->border_color));
+}
+
+static const struct scaled_scene_buffer_impl impl = {
+       .create_buffer = _create_buffer,
+       .destroy = _destroy,
+       .equal = _equal,
+};
+
+struct scaled_rect_buffer *scaled_rect_buffer_create(
+       struct wlr_scene_tree *parent, int width, int height, int border_width,
+       float fill_color[4], float border_color[4])
+{
+       /* TODO: support rounded corners for menus and OSDs */
+
+       assert(parent);
+       struct scaled_rect_buffer *self = znew(*self);
+       struct scaled_scene_buffer *scaled_buffer = scaled_scene_buffer_create(
+               parent, &impl, &cached_buffers, /* drop_buffer */ true);
+       scaled_buffer->data = self;
+       self->scaled_buffer = scaled_buffer;
+       self->scene_buffer = scaled_buffer->scene_buffer;
+       self->width = MAX(width, 1);
+       self->height = MAX(height, 1);
+       self->border_width = border_width;
+       memcpy(self->fill_color, fill_color, sizeof(self->fill_color));
+       memcpy(self->border_color, border_color, sizeof(self->border_color));
+
+       scaled_scene_buffer_invalidate_cache(scaled_buffer);
+
+       return self;
+}