用VB画4个点的NURBS曲线参考代码
Dim p(10000, 1) As Double
Dim num As Integer
Dim ptx As Single
Dim pty As Single
Dim w0, w1, w2, w3 As Single
Private Sub Command1_Click()
Dim t As Single
Dim i As Integer
Dim f0, f1, f2, f3 As Single
Picture1.DrawWidth = 3
For t = 0 To 1 Step 1 / 1000
w0 = Val(Form1.Text1.Text)
w1 = Val(Form1.Text2.Text)
w2 = Val(Form1.Text3.Text)
w3 = Val(Form1.Text4.Text)
f0 = 1 / 6 * (-t ^ 3 + 3 * t ^ 2 - 3 * t + 1)
f1 = 1 / 6 * (3 * t ^ 3 - 6 * t ^ 2 + 4)
f2 = 1 / 6 * (-3 * t ^ 3 + 3 * t ^ 2 + 3 * t + 1)
f3 = 1 / 6 * (t ^ 3)
ptx = (f0 * p(0, 0) * w0 + f1 * p(1, 0) * w1 + f2 * p(2, 0) * w2 + f3 * p(3, 0) * w3) / (f0 * w0 + f1 * w1 + f2 * w2 + f3 * w3)
pty = (f0 * p(0, 1) * w0 + f1 * p(1, 1) * w1 + f2 * p(2, 1) * w2 + f3 * p(3, 1) * w3) / (f0 * w0 + f1 * w1 + f2 * w2 + f3 * w3)
Picture1.PSet (ptx, pty), vbRed
Next
Picture1.DrawWidth = 1
For i = 0 To num - 2
Picture1.Line (p(i, 0), p(i, 1))-(p((i + 1), 0), p((i + 1), 1)), vbGreen
Next
End Sub
Private Sub Command2_Click()
Dim i As Integer
For i = 0 To num - 2
Picture1.Line (p(i, 0), p(i, 1))-(p((i + 1), 0), p((i + 1), 1)), vbWhite
Next
For i = 0 To num
Picture1.Circle (p(i, 0), p(i, 1)), 40, vbWhite
相关文档：
如何去优化你的VB程序帮助
1、如何去优化你的VB程序
Visual Basic 作为一种高级编程语言，它也有着不可避免的缺点---开发出的应用程序运行速度慢。如果我们能够程序做一些优化，那么情况将会大大改善。要优化程序运行的实际速度，常用的方法有三种：
1.尽量避免使用 Variant 变量。由于VB不能确定 Variant 变量的� ......
'代码:
Option Explicit
'======================用于查找进程和终止进程的API函数常数定义================ =====
Private Declare Function CreateToolhelpSnapshot Lib "kernel32" Alias "CreateToolhelp32Snapshot" (ByVal lFlags As Long, ByVal lProcessID As Long) As Long
Private Declare Function ProcessF ......
Dim wdapp As Word.Application
Dim wddoc As Word.Document
Dim wdtable As Word.Table
Set wdapp = CreateObject("word.application")
Set wddoc = wdapp.Documents.Add
......
MYSQL 应用十分广范，很多网站几乎都在用他，因为他的小巧和灵活性等方面让我决定要对他进行研究，到现在已经成功的不用经过ODBC，ADO等方式就可以读取和更新数据。
好了不多罗嗦，以下我来介绍总个程序的细节:
（一）API声明
1. '分配或初始化适合mysql_real_connect()的一个MYSQL对像� ......
代码如下:
Private Declare Function SetWindowPos Lib "user32" (ByVal hwnd As
Long, ByVal hWndInsertAfter As Long,& _
ByVal X As Long, ByVal Y As
Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long) As Long & _
&n ......
