...

2 files changed, 102 insertions, 0 deletions

diff --git a/demos/xcb/cairo-start/CMakeLists.txt b/demos/xcb/cairo-start/CMakeLists.txt
new file mode 100644
index 00000000..d08f2c96
--- /dev/null
+++ b/demos/xcb/cairo-start/CMakeLists.txt
@@ -0,0 +1,4 @@
+find_library(LIBRARY_CAIRO cairo REQUIRED)
+
+add_executable(demo-xcb-cairo-start main.cpp)
+target_link_libraries(demo-xcb-cairo-start PUBLIC demo-xcb-base ${LIBRARY_CAIRO})
diff --git a/demos/xcb/cairo-start/main.cpp b/demos/xcb/cairo-start/main.cpp
new file mode 100644
index 00000000..331f90d7
--- /dev/null
+++ b/demos/xcb/cairo-start/main.cpp
@@ -0,0 +1,98 @@
+#include <cairo/cairo-xcb.h>
+#include <cairo/cairo.h>
+#include <unistd.h>
+#include <xcb/xcb.h>
+#include <cstdlib>
+#include <iostream>
+
+int main() {
+  int screen_num;
+  xcb_connection_t *connection = xcb_connect(NULL, &screen_num);
+  const xcb_setup_t *setup = xcb_get_setup(connection);
+  xcb_screen_iterator_t iter = xcb_setup_roots_iterator(setup);
+  xcb_screen_t *screen = iter.data;
+
+  uint32_t mask = XCB_CW_EVENT_MASK;
+  uint32_t data[] = {XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_STRUCTURE_NOTIFY};
+
+  int width = 500;
+  int height = 500;
+
+  xcb_window_t window = xcb_generate_id(connection);
+  xcb_create_window(connection, XCB_COPY_FROM_PARENT, window, screen->root, 0,
+                    0, width, height, 10, XCB_WINDOW_CLASS_INPUT_OUTPUT,
+                    screen->root_visual, mask, data);
+  xcb_map_window(connection, window);
+  xcb_flush(connection);
+
+  xcb_visualtype_t *visual_type;
+
+  for (xcb_depth_iterator_t depth_iter =
+           xcb_screen_allowed_depths_iterator(screen);
+       depth_iter.rem; xcb_depth_next(&depth_iter)) {
+    for (xcb_visualtype_iterator_t visual_iter =
+             xcb_depth_visuals_iterator(depth_iter.data);
+         visual_iter.rem; xcb_visualtype_next(&visual_iter)) {
+      if (screen->root_visual == visual_iter.data->visual_id) {
+        visual_type = visual_iter.data;
+        break;
+      }
+    }
+  }
+
+  cairo_surface_t *surface =
+      cairo_xcb_surface_create(connection, window, visual_type, width, height);
+
+  cairo_t *cairo = cairo_create(surface);
+
+  xcb_generic_event_t *e;
+
+  auto paint = [](cairo_t *cairo, int width, int height) {
+    cairo_set_source_rgb(cairo, 1, 1, 1);
+    cairo_paint(cairo);
+    cairo_set_source_rgb(cairo, 1, 1, 0);
+    cairo_set_line_width(cairo, 5);
+    cairo_move_to(cairo, width / 2.0, 0);
+    cairo_curve_to(cairo, width, 0, width, 0, width, height / 2.0);
+    cairo_curve_to(cairo, width, height, width, height, width / 2.0, height);
+    cairo_curve_to(cairo, 0, height, 0, height, 0, height / 2.0);
+    cairo_curve_to(cairo, 0, 0, 0, 0, width / 2.0, 0);
+    cairo_stroke(cairo);
+  };
+
+  while ((e = xcb_wait_for_event(connection))) {
+    switch (e->response_type & ~0x80) {
+      case XCB_EXPOSE: {
+        paint(cairo, width, height);
+        break;
+      }
+      case XCB_CONFIGURE_NOTIFY: {
+        xcb_configure_notify_event_t *event =
+            reinterpret_cast<xcb_configure_notify_event_t *>(e);
+
+        width = event->width;
+        height = event->height;
+
+        cairo_xcb_surface_set_size(surface, width, height);
+
+        paint(cairo, width, height);
+
+        break;
+      }
+      default: {
+        /* Unknown event type, ignore it */
+        break;
+      }
+    }
+    /* Free the Generic Event */
+    free(e);
+  }
+
+  pause();
+
+  cairo_destroy(cairo);
+  cairo_surface_destroy(surface);
+  xcb_disconnect(connection);
+
+  return 0;
+}