openblocks/tools/genmesh.py
2025-02-26 22:31:58 +01:00

78 lines
2.6 KiB
Python
Executable file

#!/usr/bin/python3
# Default mesh generator
# Input from wavefront obj file
# Usage: ./genmesh.py mesh.obj > mesh.cpp
import sys
HEADER = """
static float CUBE_VERTICES[] = {
// positions // normals // texture coords
"""
FOOTER = """
};"""
file = open(sys.argv[1], "r")
vert_coords = []
vert_norms = []
vert_uvs = []
out_vertices = []
min_coords: tuple[float, float, float] | None = None
max_coords: tuple[float, float, float] | None = None
def normalize(x, y, z):
assert min_coords
assert max_coords
return ((x-max_coords[0])/(max_coords[0]-min_coords[0])+0.5, (y-max_coords[1])/(max_coords[1]-min_coords[1])+0.5, (z-max_coords[2])/(max_coords[2]-min_coords[2])+0.5)
for line in file:
if line.startswith('v '):
coords = line.split(' ')[1:]
coords = (float(coords[0]), float(coords[1]), float(coords[2]))
vert_coords.append(coords)
if not min_coords: min_coords = coords
if not max_coords: max_coords = coords
if coords[0] > max_coords[0]: max_coords = (coords[0], max_coords[1], max_coords[2])
if coords[1] > max_coords[1]: max_coords = (max_coords[0], coords[1], max_coords[2])
if coords[2] > max_coords[2]: max_coords = (max_coords[0], max_coords[1], coords[2])
if coords[0] < min_coords[0]: min_coords = (coords[0], min_coords[1], min_coords[2])
if coords[1] < min_coords[1]: min_coords = (min_coords[0], coords[1], min_coords[2])
if coords[2] < min_coords[2]: min_coords = (min_coords[0], min_coords[1], coords[2])
if line.startswith('vn '):
coords = line.split(' ')[1:]
vert_norms.append((float(coords[0]), float(coords[1]), float(coords[2])))
if line.startswith('vt '):
coords = line.split(' ')[1:]
vert_uvs.append((float(coords[0]), float(coords[1])))
if line.startswith('f '):
verts = line.split(' ')[1:]
for vert in verts:
coords, uv, normal = vert.split('/')
coords, uv, normal = int(coords), int(uv), int(normal)
coords, uv, normal = vert_coords[coords-1], vert_uvs[uv-1], vert_norms[normal-1]
coords = normalize(*coords)
# for coord in [*normal]:
# if coord > greatest_coord: greatest_coord = coord
# if coord < least_coord: least_coord = coord
out_vertices.append((coords, normal, uv))
print(HEADER)
for coords, normal, uv in out_vertices:
print(f"\t{coords[0]}, {coords[1]}, {coords[2]},\t{normal[0]}, {normal[1]}, {normal[2]},\t{uv[0]}, {uv[1]},")
print(FOOTER)