orisys-sensor-design/blender/scripts/camera_grid_stroke.py

"""Convert camera-projected patch cells to black capsule strokes.

Run with Blender's source geometry and the existing texture job. This first
camera-space prototype preserves the colour pattern's grid and visibility
projection. It does not enforce a physical minimum stroke width.
"""

import argparse
import json
import sys
from pathlib import Path

import bpy

sys.path.insert(0, str(Path(__file__).resolve().parent))

from camera_grid_stroke_geometry import capsule_in_cell, projected_stroke_uv
from camera_grid_stroke_optimizer import optimize_angles
from patch_geometry import clip_rect
from patch_projection import build_patch_geometry
from random_patch_dd02c import (
    _clipped_polygons,
    _clipped_shapes,
    _prepare_mesh_object,
    _require_object,
    _require_uv_layer,
    fill_background,
    fill_polygon,
    save_png_image,
    write_pdf_vector,
    write_svg_vector,
)

MODE = "camera_grid_capsules"
DEFAULT_PARAMS = {
    "seed": 7,
    "width_ratio": 0.42,
    "length_ratio": 0.84,
    "orientation_mode": "random",
    "proposals": 100000,
}


def _args():
    argv = sys.argv[sys.argv.index("--") + 1:] if "--" in sys.argv else []
    parser = argparse.ArgumentParser()
    parser.add_argument("--job", type=Path, required=True)
    parser.add_argument("--output-dir", type=Path, required=True)
    parser.add_argument("--params", type=Path, default=None)
    parser.add_argument("--artifact-prefix", default="camera_grid_stroke")
    parser.add_argument("--seed", type=int, default=None)
    parser.add_argument("--width-ratio", type=float, default=None)
    parser.add_argument("--length-ratio", type=float, default=None)
    parser.add_argument("--orientation-mode", choices=("random", "optimized"),
                        default=None, help="Use seeded random or experimental optimized angles")
    parser.add_argument("--proposals", type=int, default=None,
                        help="Angle changes attempted in optimized mode")
    return parser.parse_args(argv)


def _pixel_polygon(uv_polygon, width, height):
    return [(u * (width - 1), v * (height - 1))
            for u, v in clip_rect(uv_polygon, 0.0, 1.0, 0.0, 1.0)]


def _render(uv_name, geometry, settings, output_dir, width_ratio, length_ratio,
            angle_map=None, artifact_prefix="camera_grid_stroke"):
    width, height = settings["width"], settings["height"]
    nx, ny = settings["nx"], settings["ny"]
    seed = settings.get("seed") or 0
    image_name = f"CameraGridStroke_{uv_name}"
    if image_name in bpy.data.images:
        bpy.data.images.remove(bpy.data.images[image_name])
    image = bpy.data.images.new(image_name, width=width, height=height, alpha=True)
    pixels = list(image.pixels)
    fill_background(pixels, width, height, (0, 0, 0, 1))

    mesh_polygons = [_pixel_polygon(poly, width, height) for poly in geometry["mesh"]]
    mesh_polygons = [poly for poly in mesh_polygons if len(poly) >= 3]
    for poly in mesh_polygons:
        fill_polygon(None, pixels, width, height, poly, (1, 1, 1, 1))

    shapes = []
    outline_cache = {}
    for i, j, fragment, loop_uvs in geometry["camera_fragments"]:
        key = (i, j)
        if key not in outline_cache:
            outline_cache[key] = capsule_in_cell(
                i, j, nx, ny, seed, width_ratio, length_ratio,
                angle=None if angle_map is None else float(angle_map[j, i]))
        uv_poly = projected_stroke_uv(fragment, loop_uvs, outline_cache[key])
        pixel_poly = _pixel_polygon(uv_poly, width, height)
        if len(pixel_poly) < 3:
            continue
        shapes.append((pixel_poly, (0, 0, 0, 1)))
        fill_polygon(None, pixels, width, height, pixel_poly, (0, 0, 0, 1))

    image.pixels[:] = pixels
    image.update()
    label = artifact_prefix
    if angle_map is not None and artifact_prefix == "camera_grid_stroke":
        label += "_optimized"
    base = output_dir / f"{label}_{uv_name}"
    save_png_image(image, base.with_suffix(".png"))
    page_mesh = _clipped_polygons(mesh_polygons, width, height)
    page_shapes = _clipped_shapes(shapes, width, height)
    vector = settings["vector"]
    vector_args = (width, height, vector["width_mm"], vector["height_mm"])
    write_svg_vector(base.with_suffix(".svg"), *vector_args,
                     page_mesh, page_shapes, [], (0, 0, 0, 1), uv_name,
                     artwork_label="stroke")
    write_pdf_vector(base.with_suffix(".pdf"), *vector_args,
                     page_mesh, page_shapes, [], (0, 0, 0, 1),
                     artwork_label="stroke")
    print(f"{uv_name}: {len(outline_cache)} cells, {len(shapes)} projected fragments")


def main():
    args = _args()
    params = dict(DEFAULT_PARAMS)
    if args.params is not None:
        loaded = json.loads(args.params.read_text(encoding="utf-8"))
        if not isinstance(loaded, dict) or set(loaded) - set(DEFAULT_PARAMS):
            raise ValueError("invalid stroke params")
        params.update(loaded)
    for key in DEFAULT_PARAMS:
        value = getattr(args, key)
        if value is not None:
            params[key] = value
    if not 0 < params["width_ratio"] <= params["length_ratio"] < 1:
        raise ValueError("require 0 < width-ratio <= length-ratio < 1")
    if params["orientation_mode"] not in ("random", "optimized") or params["proposals"] < 1:
        raise ValueError("invalid orientation mode or proposal count")
    job = json.loads(args.job.read_text(encoding="utf-8"))
    if job.get("schema") != "orisys-sensor-design/texture-job-v3":
        raise ValueError("camera-grid strokes require a single-view texture-job-v3")
    settings = dict(job["settings"])
    settings["seed"] = params["seed"]
    obj = _prepare_mesh_object(job["objects"]["mesh"])
    cam = _require_object(job["objects"]["camera"], "CAMERA", "Camera")
    names = [entry["uv_map"] for entry in job["outputs"]]
    for name in names:
        _require_uv_layer(obj, name)
    args.output_dir.mkdir(parents=True, exist_ok=True)
    args.output_dir = args.output_dir.resolve()
    angle_map = None
    if params["orientation_mode"] == "optimized":
        angle_map, report = optimize_angles(
            settings["nx"], settings["ny"], settings.get("seed") or 0,
            params["width_ratio"], params["length_ratio"], params["proposals"],
        )
        report_path = args.output_dir / f"{args.artifact_prefix}_optimization.json"
        report_path.write_text(json.dumps(report, indent=2) + "\n", encoding="utf-8")
        print(f"Camera-grid optimization: {report}")
    geometry = build_patch_geometry(
        obj, cam, bpy.context.scene, bpy.context.evaluated_depsgraph_get(),
        names, settings["nx"], settings["ny"], settings["edge_sample_grid"],
        capture_camera_fragments=True,
    )
    for name in names:
        _render(name, geometry[name], settings, args.output_dir,
                params["width_ratio"], params["length_ratio"], angle_map,
                args.artifact_prefix)


if __name__ == "__main__":
    main()