fixing multi-raster mosaics

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "rasters"
-version = "1.15.1"
+version = "1.16.0"
 description = "raster processing toolkit"
 readme = "README.md"
 authors = [

rasters/mosaic.py

@@ -6,11 +6,12 @@
 
 if TYPE_CHECKING:
     from .raster import Raster
+    from .multi_raster import MultiRaster
     from .raster_geometry import RasterGeometry
 
 def mosaic(
-        images: Iterator[Union[Raster, str]], 
-        geometry: RasterGeometry,
+        images: Iterator[Union[Raster, MultiRaster, str]], 
+        geometry: RasterGeometry = None,
         resampling: str = "nearest") -> Raster:
     """
     Creates a mosaic from a sequence of Raster images.
@@ -30,12 +31,25 @@ def mosaic(
     """
     from .where import where  # Assuming 'where' is a function in the same package
     from .raster import Raster  # Import Raster here to avoid circular dependency
+    from .multi_raster import MultiRaster  # Import MultiRaster here to avoid circular dependency
 
-    mosaic = Raster(np.full(geometry.shape, np.nan), geometry=geometry)  # Initialize with NaN values
+    if len(images) == 0:
+        raise ValueError("No images provided for mosaicking.")
+
+    if len(images[0].shape == 2):
+        mosaic = Raster(np.full(geometry.shape, np.nan), geometry=geometry)
+    elif len(images[0].shape == 3):
+        mosaic = MultiRaster(np.full(geometry.shape, np.nan), geometry=geometry)
+    else:
+        raise ValueError("Unsupported image shape for mosaicking.")
+
     dtype = None
     nodata = None
     metadata = None
 
+    if geometry is None:
+        geometry = images[0].geometry
+
     for image in images:
         if isinstance(image, str):
             image = Raster.open(image)  # Open the image if it's a file path
@@ -50,6 +64,12 @@ def mosaic(
             mosaic = where(np.isnan(mosaic), image.to_geometry(geometry, resampling=resampling), mosaic)
 
     mosaic = mosaic.astype(dtype)  # Set the data type of the mosaic
-    mosaic = Raster(mosaic, geometry=geometry, nodata=nodata, metadata=metadata)  # Create the final Raster
+
+    if len(mosaic.shape) == 2:
+        mosaic = Raster(mosaic, geometry=geometry, nodata=nodata, metadata=metadata)  # Create the final Raster
+    elif len(mosaic.shape) == 3:
+        mosaic = MultiRaster(mosaic, geometry=geometry, nodata=nodata, metadata=metadata)  # Create the final MultiRaster
+    else:
+        raise ValueError("Unsupported mosaic shape after processing.")
 
     return mosaic