wig

commit e91f3ae17b8994a92566413d0a8a0c19912957e9
parent a3764b4ccd67c4e0625e42917f0cbf159a51b746
Author: Luke Willis <lukejw@loquat.dev>
Date:   Mon, 30 Mar 2026 00:37:24 -0400

Refactor a little and get a better mental grip on buffers

Diffstat:
M
src/main.c
 | 
68
+++++++++++++++++++++++++++++++++++++++++++++++++++++++-------------

1 file changed, 55 insertions(+), 13 deletions(-)
diff --git a/src/main.c b/src/main.c
@@ -10,11 +10,21 @@
 #include "wlr-layer-shell-unstable-v1-client-protocol.h"
 
 struct wig_window {
+  int configured;
+
   char* label;
+  uint32_t width;
+  uint32_t height;
+
+  struct wl_shm* shm;
+
+  struct wl_buffer* wl_buffer;
+  int wl_buffer_released;
+
   struct wl_surface* wl_surface;
   struct zwlr_layer_surface_v1* wlr_layer_surface;
 
-  struct wl_shm* shm;
+  uint32_t* data;
 };
 
 struct wig_state {
@@ -33,30 +43,35 @@ struct wig_state {
  */
 
 static void wl_buffer_release(void* data, struct wl_buffer* wl_buffer) {
-  wl_buffer_destroy(wl_buffer);
+  struct wig_window* window = data;
+  window->wl_buffer_released = 1;
 }
 
 static const struct wl_buffer_listener wl_buffer_listener = {
     .release = wl_buffer_release,
 };
 
-static struct wl_buffer* draw_frame(struct wig_window* state, int width,
-                                    int height) {
+int reconfigure_window(struct wig_window* window, int width, int height) {
+  if (window->data != NULL) {
+    wl_buffer_destroy(window->wl_buffer);
+    munmap(window->data, window->width * window->height * 4);
+  }
+
   int stride = width * 4;
   int size = stride * height;
 
   int fd = allocate_shm_file(size);
   if (fd == -1) {
-    return NULL;
+    return 0;
   }
 
   uint32_t* data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
   if (data == MAP_FAILED) {
     close(fd);
-    return NULL;
+    return 0;
   }
 
-  struct wl_shm_pool* pool = wl_shm_create_pool(state->shm, fd, size);
+  struct wl_shm_pool* pool = wl_shm_create_pool(window->shm, fd, size);
   struct wl_buffer* buffer = wl_shm_pool_create_buffer(
       pool, 0, width, height, stride, WL_SHM_FORMAT_XRGB8888);
   wl_shm_pool_destroy(pool);
@@ -71,10 +86,13 @@ static struct wl_buffer* draw_frame(struct wig_window* state, int width,
         data[y * width + x] = 0xFFEEEEEE;
     }
   }
+  wl_buffer_add_listener(buffer, &wl_buffer_listener, window);
+
+  window->data = data;
+  window->wl_buffer = buffer;
+  window->configured = 1;
 
-  munmap(data, size);
-  wl_buffer_add_listener(buffer, &wl_buffer_listener, NULL);
-  return buffer;
+  return 0;
 }
 
 /*
@@ -87,9 +105,22 @@ static void zwlr_layer_surface_configure(
   struct wig_window* window = data;
   zwlr_layer_surface_v1_ack_configure(zwlr_layer_surface_v1, serial);
 
-  struct wl_buffer* buffer = draw_frame(window, width, height);
-  wl_surface_attach(window->wl_surface, buffer, 0, 0);
+  /* Skip reconfiguration if the size hasn't changed */
+  if (width == window->width && height == window->height) return;
+
+  int result = reconfigure_window(window, width, height);
+
+  if (result) {
+    fprintf(stderr, "Failed to reconfigure \"%s\"", window->label);
+    return;
+  }
+
+  wl_surface_attach(window->wl_surface, window->wl_buffer, 0, 0);
   wl_surface_commit(window->wl_surface);
+  window->wl_buffer_released = 0;
+
+  window->width = width;
+  window->height = height;
 
   fprintf(stderr, "\"%s\" reconfigured\n", window->label);
   fprintf(stderr, "  %u x %u\n", width, height);
@@ -179,8 +210,12 @@ static void inner_main(void* data, int argc, char** argv) {
 
     struct wig_window* window = &state->windows[i];
     window->label = label;
+    window->width = width;
+    window->height = height;
+
     window->shm = state->shm;
 
+    window->data = NULL;
     window->wl_surface = wl_compositor_create_surface(state->compositor);
     window->wlr_layer_surface = zwlr_layer_shell_v1_get_layer_surface(
         state->layer_shell, window->wl_surface, NULL,
@@ -212,7 +247,14 @@ static void inner_main(void* data, int argc, char** argv) {
 
   /* Loop */
   while (wl_display_dispatch(state->display) != -1) {
-    /* TODO */
+    for (size_t i = 0; i < num_windows; i++) {
+      state->windows[i].data[1] = 0xFFFF00FF;
+
+      wl_surface_attach(state->windows[i].wl_surface,
+                        state->windows[i].wl_buffer, 0, 0);
+      wl_surface_damage_buffer(state->windows[i].wl_surface, 1, 0, 1, 1);
+      wl_surface_commit(state->windows[i].wl_surface);
+    }
   }
 
   /* Cleanup */