[gtk/wip/chergert/glproto] next: warn once if we truncate batches

[Christian Hergert <chergert src gnome org>]

commit 129f5841e4ce75a76abfd95d58491af84cfc6c04
Author: Christian Hergert <chergert redhat com>
Date:   Tue Feb 23 11:31:56 2021 -0800

    next: warn once if we truncate batches

 gsk/next/gskglcommandqueue.c        | 22 ++++++++++++++++++----
 gsk/next/gskglcommandqueueprivate.h |  3 +++
 2 files changed, 21 insertions(+), 4 deletions(-)
---
diff --git a/gsk/next/gskglcommandqueue.c b/gsk/next/gskglcommandqueue.c
index 622502af03..10e5f2fae4 100644
--- a/gsk/next/gskglcommandqueue.c
+++ b/gsk/next/gskglcommandqueue.c
@@ -229,6 +229,21 @@ gsk_gl_command_queue_capture_png (GskGLCommandQueue *self,
   g_free (data);
 }
 
+static inline gboolean
+will_ignore_batch (GskGLCommandQueue *self)
+{
+  if G_LIKELY (self->batches.len < G_MAXINT16)
+    return FALSE;
+
+  if (!self->have_truncated)
+    {
+      self->have_truncated = TRUE;
+      g_critical ("GL command queue too large, truncating further batches.");
+    }
+
+  return TRUE;
+}
+
 static inline guint
 snapshot_attachments (const GskGLAttachmentState *state,
                       GskGLCommandBinds          *array)
@@ -499,7 +514,7 @@ gsk_gl_command_queue_begin_draw (GskGLCommandQueue     *self,
   /* Our internal links use 16-bits, so that is our max number
    * of batches we can have in one frame.
    */
-  if (self->batches.len == G_MAXINT16)
+  if (will_ignore_batch (self))
     return;
 
   self->program_info = program;
@@ -532,8 +547,7 @@ gsk_gl_command_queue_end_draw (GskGLCommandQueue *self)
   g_assert (GSK_IS_GL_COMMAND_QUEUE (self));
   g_assert (self->batches.len > 0);
 
-  /* Max batches is 16-bit */
-  if (self->batches.len == G_MAXINT16)
+  if (will_ignore_batch (self))
     return;
 
   batch = gsk_gl_command_batches_tail (&self->batches);
@@ -648,7 +662,7 @@ gsk_gl_command_queue_clear (GskGLCommandQueue     *self,
   g_assert (GSK_IS_GL_COMMAND_QUEUE (self));
   g_assert (self->in_draw == FALSE);
 
-  if (self->batches.len == G_MAXINT16)
+  if (will_ignore_batch (self))
     return;
 
   if (clear_bits == 0)
diff --git a/gsk/next/gskglcommandqueueprivate.h b/gsk/next/gskglcommandqueueprivate.h
index 39d6fd0315..706a7ca03f 100644
--- a/gsk/next/gskglcommandqueueprivate.h
+++ b/gsk/next/gskglcommandqueueprivate.h
@@ -263,6 +263,9 @@ struct _GskGLCommandQueue
 
   /* If we're inside of a begin_draw()/end_draw() pair. */
   guint in_draw : 1;
+
+  /* If we've warned about truncating batches */
+  guint have_truncated : 1;
 };
 
 GskGLCommandQueue *gsk_gl_command_queue_new                  (GdkGLContext             *context,