VRC Houdini勉強会No.92

shader_var_baker.py

import hou

def get_declare(name, attrib):
    data_type = attrib.dataType()
    size = attrib.size()
    attrib_name = attrib.name()

    if not (data_type == hou.attribData.Float or data_type == hou.attribData.Int):
        return ''

    if data_type == hou.attribData.Int:
        return f'static const int {name}_{attrib_name}'

    if size == 1:
        return f'static const float {name}_{attrib_name}'
    elif size == 2:
        return f'static const float2 {name}_{attrib_name}'
    elif size == 3:
        return f'static const float3 {name}_{attrib_name}'
    elif size == 4:
        return f'static const float4 {name}_{attrib_name}'

    return ''

def get_element(value, element_size, data_type, precision = 5):
    if not(data_type == hou.attribData.Float or data_type == hou.attribData.Int):
        return ''
    
    if data_type == hou.attribData.Int:
        return f"{value}"

    if element_size == 1:
        return f"{value:.{precision}f}"
    elif element_size == 2:
        return f"float2({value[0]:.{precision}f}, {value[1]:.{precision}f})"
    elif element_size == 3:
        return f"float3({value[0]:.{precision}f}, {value[1]:.{precision}f}, {value[2]:.{precision}f})"
    elif element_size == 4:
        return f"float4({value[0]:.{precision}f}, {value[1]:.{precision}f}, {value[2]:.{precision}f}, {value[3]:.{precision}f})"
    else:
        return ''


def get_non_array_variable(geo, name, attrib, precision=5):
    data_type = attrib.dataType()
    attrib_name = attrib.name()
    element_size = attrib.size()
    value = geo.attribValue(attrib_name)

    if not(data_type == hou.attribData.Float or data_type == hou.attribData.Int):
        return ''
    return f'{get_declare(name, attrib)} = {get_element(value, element_size, data_type)};\n'


def get_array_variable(geo, name, attrib):
    attrib_name = attrib.name()
    attrib_type = attrib.type()
    data_type = attrib.dataType()
    element_size : int = attrib.size()

    if not(data_type == hou.attribData.Float or data_type == hou.attribData.Int):
        return ''

    if attrib_type == hou.attribType.Point:
        if data_type == hou.attribData.Int:
            data = geo.pointIntAttribValues(attrib_name)
        elif data_type == hou.attribData.Float:
            data = geo.pointFloatAttribValues(attrib_name)
        else:
            return ''
    elif attrib_type == hou.attribType.Prim:
        if data_type == hou.attribData.Int:
            data = geo.primIntAttribValues(attrib_name)
        elif data_type == hou.attribData.Float:
            data = geo.primFloatAttribValues(attrib_name)
        else:
            return ''
    elif attrib_type == hou.attribType.Global:
        if data_type == hou.attribData.Int:
            data = geo.intListAttribValue(attrib_name)
        elif data_type == hou.attribData.Float:
            data = geo.floatListAttribValue(attrib_name)
        else:
            return ''
    else:
        return ''

    array_size = len(data) // element_size

    declare =  get_declare(name, attrib) + f'[{array_size}] = {{ \n'

    array_variable = ''

    if element_size > 2:
        attrib_values = [data[i*element_size:(i+1)*element_size] for i in range(array_size)]
    else:
        attrib_values = data
    for value in attrib_values:
        array_variable += '    ' + get_element(value, element_size, data_type) + ',\n'

    return declare + array_variable + '};\n'


def main():
    node = hou.pwd()
    geo = node.geometry()

    # get HDA parameters
    parent = node.parent()
    name : str = parent.evalParm('name')
    output_file_path = parent.evalParm("path")
    debug_mode = parent.evalParm("debug_mode")
    point_attribs = parent.evalParm("point_attribs").split(' ')
    prim_attribs = parent.evalParm("prim_attribs").split(' ')
    detail_attribs = parent.evalParm("detail_attribs").split(' ')

    # detail attributes
    details = '// detail attributes \n'
    for attrib_name in detail_attribs:
        attrib = geo.findGlobalAttrib(attrib_name)
        if not attrib:
            continue
        if not attrib.isArrayType():
            details += get_non_array_variable(geo, name, attrib)
        else:
            details += get_array_variable(geo, name, attrib)

    # point attributes
    points = '// point attributes \n'
    for attrib_name in point_attribs:
        attrib = geo.findPointAttrib(attrib_name)
        if not attrib:
            continue
        points += get_array_variable(geo, name, attrib)

    # prim attributes
    prims = '// prim attributes \n'
    for attrib_name in prim_attribs:
        attrib = geo.findPrimAttrib(attrib_name)
        if not attrib:
            continue
        prims += get_array_variable(geo, name, attrib)

    # preprocessor
    macro = ascii(name)[1:-1].upper()

    text = '\n'.join([
        f'#ifndef {macro}_INCLUDED \n#define {macro}_INCLUDED \n',
        details,
        points,
        prims,
        '#endif'
    ])

    if debug_mode ==  1:
        print("-------------------")
        print(text)
        print("-------------------")

    with open(output_file_path, mode='w') as file:
        file.write(text)

main()