add embedded images

Author: kolibril13

README.md

@@ -45,5 +45,6 @@ typst_express(
 
 The Typst color remains the fill color and the generated stroke is black.
 
+
 More python examples at:
 https://kolibril13.github.io/bpy-gallery/n4typst_examples/

tests/test_svg_images_blender52.py

@@ -0,0 +1,135 @@
+"""Blender 5.2 coverage for SVG raster images produced by Typst."""
+
+from __future__ import annotations
+
+import base64
+from pathlib import Path
+import struct
+import zlib
+
+import bpy
+import pytest
+
+from typst_importer.image_import import extract_svg_images
+from typst_importer.svg_preprocessing import SVG_NS, preprocess_svg
+from typst_importer.typst_to_svg import typst_to_blender_curves
+
+
+pytestmark = pytest.mark.skipif(
+    bpy.app.version < (5, 2, 0),
+    reason="These workflows require Blender 5.2 or newer",
+)
+
+
+def _png_bytes(width=1, height=1):
+    def chunk(kind, data):
+        checksum = zlib.crc32(kind + data) & 0xFFFFFFFF
+        return struct.pack(">I", len(data)) + kind + data + struct.pack(">I", checksum)
+
+    row = b"\x00" + b"\xff\x40\x20\xff" * width
+    return (
+        b"\x89PNG\r\n\x1a\n"
+        + chunk("IHDR".encode(), struct.pack(">IIBBBBB", width, height, 8, 6, 0, 0, 0))
+        + chunk("IDAT".encode(), zlib.compress(row * height))
+        + chunk("IEND".encode(), b"")
+    )
+
+
+def _data_uri(width=1, height=1):
+    return "data:image/png;base64," + base64.b64encode(
+        _png_bytes(width, height)
+    ).decode("ascii")
+
+
+def test_preprocessing_extracts_embedded_use_image_with_viewport_geometry():
+    svg = f'''<svg xmlns="{SVG_NS}" width="100" height="100">
+      <defs><symbol id="asset" viewBox="0 0 10 20"
+        preserveAspectRatio="none">
+        <image width="10" height="20" preserveAspectRatio="none"
+          href="{_data_uri()}"/>
+      </symbol></defs>
+      <use href="#asset" x="4" y="5" width="40" height="60"/>
+    </svg>'''
+
+    images, warnings = extract_svg_images(preprocess_svg(svg))
+
+    assert warnings == []
+    assert len(images) == 1
+    xs = [corner[0] for corner in images[0]["corners"]]
+    ys = [corner[1] for corner in images[0]["corners"]]
+    assert min(xs) == pytest.approx(4.0)
+    assert max(xs) == pytest.approx(44.0)
+    assert min(ys) == pytest.approx(5.0)
+    assert max(ys) == pytest.approx(65.0)
+
+
+def test_external_images_are_contained_to_the_typst_source_folder(tmp_path: Path):
+    source_dir = tmp_path / "source"
+    source_dir.mkdir()
+    outside_image = tmp_path / "outside.png"
+    outside_image.write_bytes(_png_bytes())
+    svg = f'''<svg xmlns="{SVG_NS}" width="10" height="10">
+      <image width="10" height="10" href="../outside.png"/>
+    </svg>'''
+
+    images, warnings = extract_svg_images(
+        preprocess_svg(svg),
+        svg_dir=source_dir,
+    )
+
+    assert images == []
+    assert any("outside the SVG directory" in warning for warning in warnings)
+
+
+def test_preprocessing_bounds_recursive_use_expansion():
+    svg = f'''<svg xmlns="{SVG_NS}" width="10" height="10">
+      <defs><g id="loop">
+        <use href="#loop"/><use href="#loop"/><use href="#loop"/>
+      </g></defs>
+      <use href="#loop"/>
+    </svg>'''
+
+    with pytest.raises(ValueError, match="expansion limit"):
+        preprocess_svg(svg)
+
+
+def test_typst_image_becomes_a_packed_textured_plane(tmp_path: Path):
+    image_file = tmp_path / "pixel.png"
+    image_file.write_bytes(_png_bytes())
+    typst_file = tmp_path / "image.typ"
+    typst_file.write_text(
+        "#set page(width: auto, height: auto, margin: 0pt, fill: none)\n"
+        '#rect(width: 20pt, height: 20pt, fill: rgb("#336699"))\n'
+        '#image("pixel.png", width: 20pt)\n',
+        encoding="utf-8",
+    )
+
+    collection = typst_to_blender_curves(
+        typst_file,
+        scale_factor=100.0,
+        convert_to_mesh=False,
+    )
+
+    planes = [obj for obj in collection.objects if obj.type == "MESH"]
+    assert len(planes) == 1
+    plane = planes[0]
+    assert plane.get("typst_svg_image_object") is True
+    curves = [obj for obj in collection.objects if obj.type == "CURVE"]
+    assert len(curves) == 1
+    assert plane.get("svg_paint_index") > curves[0].get("svg_paint_index")
+    assert plane.dimensions.x == pytest.approx(curves[0].dimensions.x, abs=2e-6)
+    assert plane.dimensions.y == pytest.approx(curves[0].dimensions.y, abs=2e-6)
+    material = plane.data.materials[0]
+    texture = next(
+        node
+        for node in material.node_tree.nodes
+        if node.bl_idname == "ShaderNodeTexImage"
+    )
+    assert texture.image.packed_file
+    assert not any(
+        obj.name.startswith("__ESVG_IMG_") for obj in bpy.data.objects
+    )
+    assert not any(
+        material.get("typst_svg_blender_material") and material.users == 0
+        for material in bpy.data.materials
+    )