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我正在Python 3.3中編寫一個簡單的命令行程序，該程序讀取xyz座標的文本文件，並輸出等值三角面片。導出格式爲Wavefront目標文件（https://en.wikipedia.org/wiki/Wavefront_.obj_file）。該算法僅用於與來自地球高分辨率衛星掃描的規則間隔點。實際上，我使用了一組約340000個點，並在頂點四字形之間創建了2個三角形。外迭代沿x方向進行，而內迭代沿y方向進行。因此，爲y方向上的每個頂點創建一對三角形面，直到它在x方向上移動並重復該過程。我會告訴你的原則，模式（線臉部棱角）：Python 3.3 - 創建三維網格作爲Wavefront obj-file從規律間隔的頂點
v1--v5--v9
| \ |/|
v2--v6--v10
|/| \ |
v3--v7--v11
| \ |/|
v4--v8--v12
代碼似乎在上班途中在攪拌機或MeshLab導入的文件給出了合理的結果，除了一兩件事：所有的條紋臉對似乎沒有沿着x軸與它們的鄰居連接。顯示問題的渲染圖片： unconnected stripes。
通常，不應該有不同的表面條紋之間的垂直偏移，因爲它們沿着它們的內部邊界（-line）共享相同的頂點。具有較少頂點和較常見的低座標值的測試成功。該方法工作得很好。也許問題不在於我的網格生成器，而是在Blender，MeshLab等的座標限制內。
下面是其在返回字符串生成面和針跡的everythin一起功能：
def simpleTriangMesh(verts):
printAll("--creating simple triangulated mesh", "\n")
maxCoords = [max(verts[0]), max(verts[1]), max(verts[2])]
minCoords = [min(verts[0]), min(verts[1]), min(verts[2])]
printAll("max. coordinates (xyz): \n", maxCoords, "\n")
printAll("min. coordinates (xyz): \n", minCoords, "\n")
xVerts = 0 # amount of vertices in x-direction
yVerts = 0 # amount of vertices in y-direction
faceAmount = 0 # amount of required faces to skin grid
i = 0
temp = verts[0][0]
while(i < len(verts[0])):
if(temp < verts[0][i]):
yVerts = int(i)
break
temp = verts[0][i]
i += 1
xVerts = int(len(verts[0])/float(yVerts))
faceAmount = ((xVerts - 1) * (yVerts - 1)) * 2
printAll("vertices in x direction: ", xVerts, "\n")
printAll("vertices in y direction: ", yVerts, "\n")
printAll("estimated amount of triangle faces: ",
faceAmount, "\n")
printAll("----generating vertex triangles representing the faces", "\n")
# list of vertex-index quadrupels representing the faces
faceList = [[0 for line in range(0, 3)] for face in range(0, int(faceAmount))]
f = 0
v = 0
# rather to draw hypotenuse of the triangles from topleft to bottomright
# or perpendicular to that (topright to bottomleft)
tl = True # the one that changes in y-direction
tl_rem = False # to remember the hypotenuse direction of the last topmost faces
while(f < len(faceList)):
# prevent creation of faces at the bottom line
# + guarantees that v = 1 when creating the first face
if((v % yVerts) == 0):
v += 1
tl = not tl_rem
tl_rem = tl
if(tl):
faceList[f][0] = v
faceList[f][1] = v + yVerts
faceList[f][2] = v + yVerts + 1
f += 1
faceList[f][0] = v
faceList[f][1] = v + yVerts + 1
faceList[f][2] = v + 1
else:
faceList[f][0] = v
faceList[f][1] = v + yVerts
faceList[f][2] = v + 1
f += 1
faceList[f][0] = v + 1
faceList[f][1] = v + yVerts
faceList[f][2] = v + yVerts + 1
f += 1
v += 1
tl = not tl
printAll("----preparing obj-file-content for export", "\n")
rectMesh_Obj = "" # string containing the mesh in obj-format (ascii)
tempVerts = ""
tempFaces = ""
row = 0
while(row < len(verts[0])):
# temp = ("v" + " " + str(verts[0][row]) + " " + str(verts[1][row])
# + " " + str(verts[2][row]) + "\n")
temp = ("v" + " " + str(verts[0][row]) + " " + str(verts[2][row])
+ " " + str(verts[1][row]) + "\n")
tempVerts += temp
row += 1
row = 0
while(row < len(faceList)):
temp = ("f"
+ " " + str(int(faceList[row][0]))
+ " " + str(int(faceList[row][1]))
+ " " + str(int(faceList[row][2]))
# + " " + str(int(faceList[row][3]))
+ "\n")
tempFaces += temp
row += 1
rectMesh_Obj += tempVerts + tempFaces
return(rectMesh_Obj)
其被輸入到該函數的頂點 - 變量具有2維列表的形式，類似到：
# x y z
vertsExample = [[3334, 3333, 3332], [2555, 2554, 2553], [10.2, 5.2, 6.7]]
我希望你們中的一些人能夠幫助我擺脫苦難。如果需要更多解釋，請告訴我，我會將其添加到第一篇文章中。
