Fix SDF text rendering in web demo

maplibre/src/sdf/collision_system.rs

@@ -72,14 +72,17 @@ impl System for CollisionSystem {
             let coords = view_tile.coords();
             if let Some(component) = world.tiles.query::<&SymbolLayersDataComponent>(coords) {
                 for layer in &component.layers {
-                    let mut feature_metadata = vec![
-                        SDFShaderFeatureMetadata::default();
+                    let metadata_count = if layer.features.is_empty() {
+                        layer.new_buffer.buffer.vertices.len()
+                    } else {
                         layer
                             .features
                             .last()
                             .map(|feature| feature.indices.end)
                             .unwrap_or_default()
-                    ];
+                    };
+                    let mut feature_metadata =
+                        vec![SDFShaderFeatureMetadata { opacity: 1.0 }; metadata_count];
 
                     for feature in &layer.features {
                         // calculate where tile is
@@ -195,12 +198,12 @@ impl System for CollisionSystem {
                             );
 
                             for index in feature.indices.clone() {
-                                let index = layer.buffer.buffer.indices[index] as usize;
+                                let index = layer.new_buffer.buffer.indices[index] as usize;
                                 feature_metadata[index].opacity = 1.0;
                             }
                         } else {
                             for index in feature.indices.clone() {
-                                let index = layer.buffer.buffer.indices[index] as usize;
+                                let index = layer.new_buffer.buffer.indices[index] as usize;
                                 feature_metadata[index].opacity = 0.0;
                             }
 

maplibre/src/sdf/upload_system.rs

@@ -101,14 +101,18 @@ fn upload_symbol_layer(
                 continue;
             };
 
-            // Assign every feature in the layer the color from the style
-            let feature_metadata = iter::repeat(SDFShaderFeatureMetadata { opacity: 0.0 })
-                .take(
-                    features
-                        .last()
-                        .map(|feature| feature.indices.end)
-                        .unwrap_or_default(),
-                )
+            // Per-vertex opacity metadata. Default to 1.0 (visible) so text renders
+            // even when collision detection features are not yet populated.
+            let metadata_count = if features.is_empty() {
+                buffer.buffer.vertices.len()
+            } else {
+                features
+                    .last()
+                    .map(|feature| feature.indices.end)
+                    .unwrap_or_default()
+            };
+            let feature_metadata = iter::repeat(SDFShaderFeatureMetadata { opacity: 1.0 })
+                .take(metadata_count)
                 .collect::<Vec<_>>();
 
             // FIXME avoid uploading empty indices

maplibre/src/vector/process_vector.rs

@@ -99,7 +99,7 @@ pub fn process_vector_tile<T: VectorTransferables, C: Context>(
                                 coords,
                                 tessellator.quad_buffer.into(),
                                 tessellator_new.quad_buffer.into(),
-                                tessellator.features,
+                                tessellator_new.features,
                                 original_layer,
                             )?;
                         }

maplibre/src/vector/transferables.rs

@@ -285,7 +285,7 @@ impl SymbolLayerTessellated for crate::vector::transferables::DefaultSymbolLayer
     }
 
     fn is_empty(&self) -> bool {
-        self.buffer.usable_indices == 0
+        self.new_buffer.usable_indices == 0
     }
 
     fn to_bucket(self) -> SymbolLayerData {