rerun rrd compact: always put blueprints at the start of the recordings (#6998)

Slight modification to `rerun rrd compact` in order to make sure that,
if the recording contains one or more blueprints, they end up at the
beginning of it, otherwise the experience would suck since the blueprint
would only get loaded once all the data had finished streaming in.

Author: teh-cmc

crates/top/rerun/src/run.rs

@@ -9,7 +9,7 @@ use itertools::{izip, Itertools};
 
 use re_data_source::DataSource;
 use re_log_types::{LogMsg, SetStoreInfo};
-use re_sdk::log::Chunk;
+use re_sdk::{log::Chunk, StoreKind};
 use re_smart_channel::{ReceiveSet, Receiver, SmartMessagePayload};
 
 #[cfg(feature = "web_viewer")]
@@ -661,16 +661,32 @@ fn run_compact(path_to_input_rrd: &Path, path_to_output_rrd: &Path) -> anyhow::R
     let mut rrd_out = std::fs::File::create(path_to_output_rrd)
         .with_context(|| format!("{path_to_output_rrd:?}"))?;
 
-    let messages: Result<Vec<Vec<LogMsg>>, _> = entity_dbs
-        .into_values()
+    let messages_rbl: Result<Vec<Vec<LogMsg>>, _> = entity_dbs
+        .values()
+        .filter(|entity_db| entity_db.store_kind() == StoreKind::Blueprint)
         .map(|entity_db| entity_db.to_messages(None /* time selection */))
         .collect();
-    let messages = messages?;
-    let messages = messages.iter().flatten();
+    let messages_rbl = messages_rbl?;
+    let messages_rbl = messages_rbl.iter().flatten();
+
+    let messages_rrd: Result<Vec<Vec<LogMsg>>, _> = entity_dbs
+        .values()
+        .filter(|entity_db| entity_db.store_kind() == StoreKind::Recording)
+        .map(|entity_db| entity_db.to_messages(None /* time selection */))
+        .collect();
+    let messages_rrd = messages_rrd?;
+    let messages_rrd = messages_rrd.iter().flatten();
 
     let encoding_options = re_log_encoding::EncodingOptions::COMPRESSED;
-    re_log_encoding::encoder::encode(version, encoding_options, messages, &mut rrd_out)
-        .context("Message encode")?;
+    re_log_encoding::encoder::encode(
+        version,
+        encoding_options,
+        // NOTE: We want to make sure all blueprints come first, so that the viewer can immediately
+        // set up the viewport correctly.
+        messages_rbl.chain(messages_rrd),
+        &mut rrd_out,
+    )
+    .context("Message encode")?;
 
     let rrd_out_size = rrd_out.metadata().ok().map(|md| md.len());