form1.frm

本程序所反应的是在测量中被广泛应用的全球定位系统（Global Position System）在空间中的形象以及基本的工作原理。GPS由三部分组成：空间部分、地面控制系统以及用户部分。

VERSION 5.00
Begin VB.Form Form1 
   AutoRedraw      =   -1  'True
   BorderStyle     =   1  'Fixed Single
   Caption         =   "模拟GPS定位系统"
   ClientHeight    =   8850
   ClientLeft      =   585
   ClientTop       =   330
   ClientWidth     =   10575
   Icon            =   "Form1.frx":0000
   LinkTopic       =   "Form1"
   MaxButton       =   0   'False
   MinButton       =   0   'False
   ScaleHeight     =   8850
   ScaleWidth      =   10575
   Begin VB.CommandButton Command7 
      Caption         =   "缩小"
      Height          =   375
      Left            =   9165
      TabIndex        =   6
      Top             =   3360
      Width           =   975
   End
   Begin VB.CommandButton Command6 
      Caption         =   "退出"
      Height          =   375
      Left            =   9165
      TabIndex        =   5
      Top             =   4560
      Width           =   975
   End
   Begin VB.CommandButton Command5 
      Caption         =   "恢复"
      Height          =   375
      Left            =   9165
      TabIndex        =   4
      Top             =   3960
      Width           =   975
   End
   Begin VB.CommandButton Command4 
      Caption         =   "放大"
      Height          =   375
      Left            =   9165
      TabIndex        =   3
      Top             =   2760
      Width           =   975
   End
   Begin VB.CommandButton Command3 
      Caption         =   "停止"
      Height          =   375
      Left            =   9165
      TabIndex        =   2
      Top             =   2160
      Width           =   975
   End
   Begin VB.Timer Timer1 
      Left            =   8880
      Top             =   240
   End
   Begin VB.CommandButton Command2 
      Caption         =   "演示"
      Height          =   375
      Left            =   9165
      TabIndex        =   1
      Top             =   1560
      Width           =   975
   End
   Begin VB.PictureBox Picture1 
      AutoRedraw      =   -1  'True
      BackColor       =   &H00000000&
      Height          =   8535
      Left            =   120
      ScaleHeight     =   8475
      ScaleWidth      =   8475
      TabIndex        =   0
      Top             =   120
      Width           =   8535
   End
   Begin VB.Label Label8 
      Height          =   255
      Left            =   8760
      TabIndex        =   14
      Top             =   6960
      Width           =   1815
   End
   Begin VB.Label Label7 
      Height          =   255
      Left            =   8760
      TabIndex        =   13
      Top             =   6720
      Width           =   1815
   End
   Begin VB.Label Label2 
      Height          =   255
      Left            =   8760
      TabIndex        =   12
      Top             =   6000
      Visible         =   0   'False
      Width           =   1695
   End
   Begin VB.Label Label1 
      Height          =   375
      Left            =   8760
      TabIndex        =   11
      Top             =   5520
      Visible         =   0   'False
      Width           =   1695
   End
   Begin VB.Label Label6 
      Height          =   255
      Left            =   8760
      TabIndex        =   10
      Top             =   6480
      Width           =   1815
   End
   Begin VB.Label Label5 
      Height          =   375
      Left            =   8760
      TabIndex        =   9
      Top             =   6000
      Width           =   1695
   End
   Begin VB.Label Label4 
      Height          =   255
      Left            =   8760
      TabIndex        =   8
      Top             =   6480
      Visible         =   0   'False
      Width           =   1695
   End
   Begin VB.Label Label3 
      Height          =   300
      Left            =   8760
      TabIndex        =   7
      Top             =   6240
      Visible         =   0   'False
      Width           =   1770
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Const pi = 3.14159265358
Dim isdown As Boolean, intev As Single
Dim weixing3dx(1 To 4) As Double, weixing3dy(1 To 4) As Double, weixing3dz(1 To 4) As Double
Dim weixing2dx(1 To 4) As Double, weixing2dy(1 To 4) As Double
Dim juli(1 To 6, 1 To 4) As Double
Dim juli1(1 To 24) As Double
Dim dx1 As Single, dx2 As Single, dx3 As Single, dx4 As Single
Dim mx As Double, my As Double


Private Sub Command2_Click()
 Timer1.Interval = 1
 Command2.Enabled = False
 Command3.Enabled = True
 Command5.Enabled = False
 Command6.Enabled = False
End Sub

Private Sub Command3_Click()
 pic1control = 0
 Label1.Caption = ""
 Label2.Caption = ""
 Label3.Caption = ""
 Label4.Caption = ""
 Label5.Caption = ""
 Label6.Caption = ""
 Label7.Caption = ""
 Label8.Caption = ""
 Command2.Enabled = True
 Command3.Enabled = False
 Command5.Enabled = True
 Command6.Enabled = True
 Timer1.Interval = 0
End Sub

Private Sub Command4_Click()
 Picture1.Cls
 If rou1 > 10000 Then
   rou1 = rou1 - 10000
 End If
 drawearth sita1, fai1, rou1, d1, zzj
' If pic1control = 1 And Timer1.Interval = 0 Then
'   Dim locationx1 As Double, locationy1 As Double, locationz1 As Double
'   linxx = locationx
'   linyy = locationy
'   linzz = locationz
'   locationx1 = linxx
'   locationy1 = linyy * Cos(qingjiao * pi / 180) + linzz * Sin(qingjiao * pi / 180)
'   locationz1 = -linyy * Sin(qingjiao * pi / 180) + linzz * Cos(qingjiao * pi / 180)
'
'
'   linxx = locationx1
'   linyy = locationy1
'   linzz = locationz1
'   locationx1 = linxx * Cos(zzhuanjiao * pi / 180) + linyy * Sin(zzhuanjiao * pi / 180)
'   locationy1 = -linxx * Sin(zzhuanjiao * pi / 180) + linyy * Cos(zzhuanjiao * pi / 180)
'   locationz1 = linzz
'
'   picx = zbchangex(locationx1, locationy1, locationz1, sita1, fai1, rou1, d1)
'   picy = zbchangey(locationx1, locationy1, locationz1, sita1, fai1, rou1, d1)
'   Picture1.DrawStyle = 0
'   Picture1.DrawWidth = 2
'   Picture1.Line (picx, picy + 50)-(picx - 50, picy - 25), vbGreen
'   Picture1.Line -(picx + 50, picy - 25), vbGreen
'   Picture1.Line -(picx, picy + 50), vbGreen
' End If
' Picture1.DrawWidth = 1
End Sub

Private Sub Command5_Click()
 Picture1.Cls
 pic1control = 0
 Label1.Caption = ""
 Label2.Caption = ""
 Label3.Caption = ""
 Label4.Caption = ""
 Label5.Caption = ""
 Label6.Caption = ""
 Label7.Caption = ""
 Label8.Caption = ""
 sita1 = 30 * pi / 180
 fai1 = 70 * pi / 180
 rou1 = 55000
 d1 = 7000
 zzj = 50
 drawearth sita1, fai1, rou1, d1, zzj
 'stltqishi = 0 '将卫星的起始角定义为0
End Sub

Private Sub Command6_Click()
 End
End Sub

Private Sub Command7_Click()
 Picture1.Cls
 rou1 = rou1 + 10000
 drawearth sita1, fai1, rou1, d1, zzj