Houdini----Python

這篇記錄自己學習H過程中Py的部分腳本工具。

#來自呂老師的一個教程：
#需要注意的就是Houdini中設置父子關係的時候，如果要保留子級的原始的transform，在界面操作中要勾選Keep Position When Parenting,而在Py中操作時相當於保存transform，設置父子關係後在把transform復原回去


def createParentGeo(num):
    geo = []
    i = 0
    while i < num:
        geo.append(hou.node('/obj').createNode('geo'))
        geo[i].parm('ty').set(3*i)
        i+=1
    j = 1
    while j<num:
        xform = geo[j].worldTransform()
        geo[j].setFirstInput(geo[j-1])
        geo[j].moveToGoodPosition()
        geo[j].setWorldTransform(xform)
        j+=1

def cancelParents():
    selgeo = hou.selectedNodes()
    i = 0
    while i<len(selgeo):
        xform = selgeo[i].worldTransform()
        selgeo[i].setFirstInput(None)
        selgeo[i].setWorldTransform(xform)
        i+=1
        

#根據距離分組

#獲取當前的節點
node = hou.pwd()

#獲取到當前節點的幾何體（上級傳入的幾何體）
geo = node.geometry()

#創建一個距離組
pointGrp = geo.createPointGroup('dist_group')

#獲取Parameters
dist = hou.parm('distance').eval()
pos = hou.parmTuple('position').eval()

#功能部分
for point in geo.points():
    length = hou.Vector3(point.position() - hou.Vector3(pos)).length()
    if length < dist:
        pointGrp.add(point)
    

# 在已知點的周圍撒點
# This code is called when instances of this SOP cook.
node = hou.pwd()
geo = node.geometry()


num = hou.parm('insertNum').eval()
range = hou.parm('range').eval()
seed = hou.parm('seed').eval()
delete = hou.parm('delOriginPoints').eval()

pos = []


for point in geo.points():
    i = 0
    while i < num:
        rnd = hou.hmath.rand(point.number())#rand($PT)
        xrand = point.position()[0] + (hou.hmath.rand(rnd+i+0.1+seed) - 0.5) * 2 * range
        yrand = point.position()[1] + (hou.hmath.rand(rnd+i+2.6+seed) - 0.5) * 2 * range
        zrand = point.position()[2] + (hou.hmath.rand(rnd+i+9.3+seed) - 0.5) * 2 * range
        
        randPos = hou.Vector3(xrand, yrand, zrand)
        
        pos.append(randPos)
        i += 1

if delete == 1:
    geo.clear()

j = 0
while j < len(pos):
    p = geo.createPoint()
    p.setPosition(pos[j])
    j += 1

 

 

# 在每一個點組的平均位置上生成一個點
# This code is called when instances of this SOP cook.
node = hou.pwd()
geo = node.geometry()

positionList = []

numPointGroup = len(geo.pointGroups())

for currentGroup in geo.pointGroups():
    xsum = ysum = zsum = 0
    for currentPoint in currentGroup.points():
        xsum += currentPoint.position()[0]
        ysum += currentPoint.position()[1]
        zsum += currentPoint.position()[2]
        
    xaverage = xsum / len(currentGroup.points())
    yaverage = ysum / len(currentGroup.points())
    zaverage = zsum / len(currentGroup.points())
    
    positionList.append((xaverage, yaverage, zaverage))

geo.clear()


for i in range(0, numPointGroup, 1):
    point = geo.createPoint()
    point.setPosition(positionList[i])

 

# 用點驅動模型運動，第一個輸入點是驅動的模型，第二個輸入點是動畫的點，第三個是動畫點的初始位置
# This code is called when instances of this SOP cook.
node = hou.pwd()
geo = node.geometry()

input2_geo = node.inputs()[1].geometry()
input3_geo = node.inputs()[2].geometry()

initPos = []

for input3point in input3_geo.points():
    initPos.append(input3point.position())

tempPos = []

for input2Point in input2_geo.points():
    tempPos.append(input2Point.position())

i = 0
for currentGroup in geo.pointGroups():
    for currentPoint in currentGroup.points():
        pos = tempPos[i] - initPos[i] + currentPoint.position()
        pos = hou.Vector3(pos)
        currentPoint.setPosition(pos)
    i+=1
        
    

# This code is called when instances of this SOP cook.
# 把每一幀的屬性值累加起來，如果在時間軸上收到輸入幀數，此節點無效
node = hou.pwd()
geo = node.geometry()

attribName = node.parm('attribname').eval()

accumulateName = 'accumulated_' + attribName

points_tmp = geo.points()

#這裏的第三個參數是默認值，如果只寫0的話會被默認成整數，如果是浮點數要寫成0.0
geo.addAttrib(hou.attribType.Point, accumulateName, 0.0)

if hou.frame()==1:
    accumulate = []
    for i in range(0,len(points_tmp),1):
        accumulate.append( points_tmp[i].attribValue(attribName))
        points_tmp[i].setAttribValue(accumulateName,accumulate[i])
else:
    for i in range(0, len(points_tmp), 1):
        accumulate[i] += points_tmp[i].attribValue(attribName)
        points_tmp[i].setAttribValue(accumulateName,accumulate[i])