use size/offset to specify buffer cursor data section (#144)

* use size/offset to specify buffer cursor data section

* ignore typing issues

examples/pathtracer/pathtracer.py

@@ -140,7 +140,9 @@ def __init__(self, base_color: "sgl.float3param" = sgl.float3(0.5)):
 
 class Mesh:
     def __init__(
-        self, vertices: npt.NDArray[np.float32], indices: npt.NDArray[np.uint32]
+        self,
+        vertices: npt.NDArray[np.float32],  # type: ignore
+        indices: npt.NDArray[np.uint32],  # type: ignore
     ):
         super().__init__()
         assert vertices.ndim == 2 and vertices.dtype == np.float32

src/sgl/core/tests/test_bitmap.py

@@ -34,7 +34,7 @@ def create_test_array(
     width: int,
     height: int,
     channels: int,
-    dtype: npt.DTypeLike,
+    dtype: npt.DTypeLike,  # type: ignore
     type_range: tuple[float, float],
 ):
     img = np.zeros((height, width, channels), dtype)

src/sgl/core/tests/test_struct.py

@@ -44,8 +44,8 @@ def check_conversion(
     converter: StructConverter,
     src_fmt: str | bytes,
     dst_fmt: str | bytes,
-    src_values: npt.ArrayLike,
-    ref_values: Optional[npt.ArrayLike] = None,
+    src_values: npt.ArrayLike,  # type: ignore
+    ref_values: Optional[npt.ArrayLike] = None,  # type: ignore
     err_thresh: float = 1e-6,
 ):
     # print("\nsrc_values: " + str(src_values))

src/sgl/device/buffer_cursor.cpp

@@ -411,17 +411,12 @@ BufferCursor::BufferCursor(ref<TypeLayoutReflection> element_layout, ref<Buffer>
     m_owner = true;
 }
 
-BufferCursor::BufferCursor(
-    ref<TypeLayoutReflection> element_layout,
-    ref<Buffer> resource,
-    size_t element_count,
-    size_t first_element
-)
+BufferCursor::BufferCursor(ref<TypeLayoutReflection> element_layout, ref<Buffer> resource, size_t size, size_t offset)
     : m_element_type_layout(std::move(element_layout))
 {
     m_resource = std::move(resource);
-    m_size = m_element_type_layout->stride() * element_count;
-    m_offset = m_element_type_layout->stride() * first_element;
+    m_size = size;
+    m_offset = offset;
     m_buffer = nullptr;
     m_owner = true;
 }

src/sgl/device/buffer_cursor.h

@@ -103,12 +103,7 @@ class SGL_API BufferCursor : Object {
     BufferCursor(ref<TypeLayoutReflection> element_layout, ref<Buffer> resource);
 
     /// Create as a view onto a section of a buffer resource.
-    BufferCursor(
-        ref<TypeLayoutReflection> element_layout,
-        ref<Buffer> resource,
-        size_t element_count,
-        size_t first_element
-    );
+    BufferCursor(ref<TypeLayoutReflection> element_layout, ref<Buffer> resource, size_t size, size_t offset);
 
     ~BufferCursor();
 

src/sgl/device/python/buffer_cursor.cpp

@@ -93,8 +93,8 @@ SGL_PY_EXPORT(device_buffer_cursor)
             nb::init<ref<TypeLayoutReflection>, ref<Buffer>, size_t, size_t>(),
             "element_layout"_a,
             "buffer_resource"_a,
-            "element_count"_a,
-            "first_element"_a,
+            "size"_a,
+            "offset"_a,
             D_NA(BufferCursor, BufferCursor)
         )
         .def_prop_ro("element_type_layout", &BufferCursor::element_type_layout, D_NA(BufferCursor, type_layout))

src/sgl/device/tests/test_declrefs.py

@@ -4,7 +4,7 @@
 import sys
 import sgl
 from pathlib import Path
-from deepdiff import DeepDiff
+from deepdiff.diff import DeepDiff
 
 sys.path.append(str(Path(__file__).parent))
 import sglhelpers as helpers

src/sgl/device/tests/test_shader_cursor.py

@@ -31,7 +31,7 @@ class TypeInfo:
     # encoding of read back data
     struct: str
     # numpy dtype
-    dtype: DTypeLike
+    dtype: DTypeLike  # type: ignore
 
 
 TYPE_INFOS = {

src/sgl/utils/tests/test_texture_loader.py

@@ -144,7 +144,7 @@ def create_test_array(
     width: int,
     height: int,
     channels: int,
-    dtype: npt.DTypeLike,
+    dtype: npt.DTypeLike,  # type: ignore
     type_range: tuple[float, float],
 ):
     img = np.zeros((height, width, channels), dtype)