dreamcast/tools/obj_to_cpp.py

113 lines
2.5 KiB
Python

from dataclasses import dataclass
import sys
from generate import renderer
with open(sys.argv[1], 'r') as f:
lines = f.read().split("\n")
@dataclass
class Vertex:
x: float
y: float
z: float
@dataclass
class VertexNormal:
vertex: int
normal: int
Face = tuple[VertexNormal, VertexNormal, VertexNormal]
name = None
vertices = []
normals = []
faces = []
def parse_object(line):
h, name = line.split()
assert h == 'o'
return name.lower()
def parse_vertex(line):
h, *xyz = line.split()
assert h == 'v' or h == 'vn'
assert len(xyz) == 3
return Vertex(*map(float, xyz))
def maybe_int(i, offset):
if i.strip() == "":
return None
else:
return int(i) + offset
def parse_face(line):
h, *tri = line.split()
assert h == 'f'
assert len(tri) == 3
def parse_ixs(ixs):
ix = ixs.split('/')
assert len(ix) == 3
vertex_ix, uv_ix, normal_ix = [
maybe_int(iix, offset=-1)
for iix in ix
]
return VertexNormal(vertex_ix, normal_ix)
return tuple(map(parse_ixs, tri))
def generate_vertices(vertices):
yield "constexpr vec3 vertices[] = {"
for v in vertices:
yield f"{{ {v.x:9f}f, {v.y:9f}f, {v.z:9f}f }},"
yield "};"
yield ""
def generate_normals(normals):
yield "constexpr vec3 normals[] = {"
for n in normals:
yield f"{{ {n.x:9f}f, {n.y:9f}f, {n.z:9f}f }},"
yield "};"
yield ""
def generate_faces(faces):
yield "constexpr face faces[] = {"
for f in faces:
inner = ", ".join(f"{{{vn.vertex:2}, {vn.normal:2}}}" for vn in f)
yield f"{{{inner}}},"
yield "};"
yield ""
yield "constexpr uint32_t num_faces = (sizeof (faces)) / (sizeof (face));"
yield ""
for line in lines:
if line.startswith('o '):
assert name is None
name = parse_object(line)
elif line.startswith('v '):
vertices.append(parse_vertex(line))
elif line.startswith('vn '):
normals.append(parse_vertex(line))
elif line.startswith('f '):
faces.append(parse_face(line))
else:
pass
def generate_namespace():
assert name is not None
yield "#pragma once"
yield ""
yield '#include "geometry.hpp"'
yield ""
yield f"namespace {name} {{"
yield from generate_vertices(vertices)
yield from generate_normals(normals)
yield from generate_faces(faces)
yield "}"
render, out = renderer()
render(generate_namespace())
sys.stdout.write(out.getvalue())