pyfmm.c_interfaces 源代码

"""
    :file:     c_interfaces.py  
    :author:   Zhu Dengda (zhudengda@mail.iggcas.ac.cn)  
    :date:     2023-04

    该文件包括 C库的调用接口  

"""

import os
from ctypes import *
from typing import Any

PDOUBLE = POINTER(c_double)
PFLOAT = POINTER(c_float)
PINT = POINTER(c_int)

USE_FLOAT:bool = False
"""libfmm库中走时和慢度数组是否使用单精度浮点数"""
NPCT_REAL_TYPE:str = 'f8'

C_FastMarching:Any = None
C_FMM_raytracing:Any = None



def load_c_lib(use_float:bool=False):
    r'''
        加载单精度或双精度的C库，修改c_interfaces下的NPCT_REAL_TYPE变量和C函数接口

        :param       use_float:    是否使用单精度
    '''
    global USE_FLOAT, NPCT_REAL_TYPE, C_FastMarching, C_FMM_raytracing

    USE_FLOAT = use_float
    NPCT_REAL_TYPE = 'f4' if USE_FLOAT else 'f8'
    _suffix = 'float' if USE_FLOAT else 'double'

    REAL = c_float if USE_FLOAT else c_double
    PREAL = POINTER(REAL)

    libfmm = cdll.LoadLibrary(
        os.path.join(
            os.path.abspath(os.path.dirname(__file__)), 
            f"C_extension/lib/libfmm_{_suffix}.so"))
    """libfmm库"""


    C_FastMarching = libfmm.FastMarching
    """C库中计算走时场的主函数 FastMarching, 详见C API同名函数"""

    C_FMM_raytracing = libfmm.FMM_raytracing
    """C库中根据走时场进行射线追踪 FMM_raytracing, 详见C API同名函数"""


    C_FastMarching.restype = None 
    C_FastMarching.argtypes = [
        PDOUBLE, c_int,
        PDOUBLE, c_int,
        PDOUBLE, c_int,
        c_double, c_double, c_double, 
        c_int, PREAL,
        PREAL, c_bool,
        c_int, c_int, c_bool
    ]


    C_FMM_raytracing.restype = c_float 
    C_FMM_raytracing.argtypes = [
        PDOUBLE, c_int,
        PDOUBLE, c_int,
        PDOUBLE, c_int,
        c_double, c_double, c_double, 
        c_double, c_double, c_double, c_double, c_double, 
        PREAL, c_bool,
        PDOUBLE, PINT
    ]