太阳系行星轨道及运行

太阳系行星轨道及运行动画演示本程序对太阳系行星、卫星运行情况进行动画演示。

具有以下功能：1.可单独（或全部）显示或隐藏某个天体、运行轨道、天体名称。

2.可调节演示速度、画面比列、观察角度（从天球赤道到天球北极观察太阳系）。

3.可将某个天体（例如月亮）设置为屏幕中间静止不动的天体，观察其他天体相对于该天体运行的情况。

本程序改进版见：太阳系行星轨道及运行-3D立体动画演示通过设置不同的参数，可得到许多美丽而奇妙的图案，如下：'需在窗体放置以下3 个控件，所有控件均采用默认设置：' Picture1，Command1，Timer1' 注意：在属性窗口将Command1 的Index 属性设置为0'其次，为窗体添加一个名为mFast 的菜单，再为mFast 添加一个名为mmFast 的下级子菜单，并将mmFast 的索引设置为0。

' 即：mmFast 是以序号0 开头的菜单数组控件的第一个。

'以下是窗体代码，在VB6.0 调试通过：Dim ctD() As tyD, ctDs As Long, ctP As Single, ctCenter As LongDim ctBi As Single, ctV As Single, ctTrack As Boolean, ctBW As Long Dim ctSeeJ As Long, ctSeeBi As Single, ctSet As MenuSet'定义表示天体的数据类型Private Type tyDCap As String '天体名称r As Long '天体半径（像素，下同）a As Single '轨道：横半径b As Single '轨道：纵半径c As Single '轨道：焦点e As Single '轨道：偏心率IsHui As Boolean '是否彗星Father As Long '父天体序号：轨道焦点上的天体Se As Long '颜色V As Single '运行角速度Jiao As Single '某时刻的与父天体连线角度X As Single '天体当前坐标Y As SinglexUp As Single '上一时刻坐标yUp As SingleVisible As Boolean '是否显示：球体ShowCap As Boolean '是否显示：标题GuiDao As Boolean '是否显示：轨道End TypeEnum MenuSet'以下为选项菜单标示ms_All = -2ms_NoAll = -1'以下为按钮标示ms_RunStop = 0 '开始/暂停ms_Step '步进，下一位置ms_UnRun '后退ms_Track '轨迹：显示/隐藏ms_DefSet '默认设置ms_Center '参照系ms_Visible '天体：显示/隐藏ms_ShowCap '天体名称ms_GuiDao '轨道ms_Bi '缩放比ms_V '速度ms_SeeJ '视角End EnumPrivate Sub Form_Load()Me.ScaleMode = 3: Me.Caption = "太阳系行星运行演示"mFast.Visible = False: ctP = 3.1415926Timer1.Interval = 25: Timer1.Enabled = TrueCall Init'Me.WindowState = vbMaximized '最大化窗体'窗体大小为屏幕的3/4，居中Me.Move Screen.Width * 0.1, Screen.Height * 0.1, Screen.Width * 0.8, Screen.Height * 0.8End SubPrivate Sub Form_Resize()Dim I As Long, L As Single, T As Single, H As Single, H1 As Single, W As Single'设置控件位置H1 = Me.TextHeight("A"): L = H1 * 0.3: T = LL = 3For I = 0 To Command1.Count - 1W = Me.TextWidth(Command1(I).Caption & "ab")Command1(I).Move L, T, W, H1 * 2L = L + W + 3NextT = T * 2 + Command1(0).Height: H = Me.ScaleHeight - TIf H > 0 Then Picture1.Move 0, T, Me.ScaleWidth, H'将Picture1 的中心设置为坐标原点Picture1.ScaleMode = 3Picture1.ScaleLeft = -Picture1.ScaleWidth * 0.5Picture1.ScaleTop = -Picture1.ScaleHeight * 0.5Picture1.ClsCall Run1End SubPrivate Sub Init()'初始化天体参数Dim I As Long, V As Single, J As SinglectBW = 0 ' 40 '四周边界空白区，仅用于调试。

调试完毕应设为0 。

调试代码**** Picture1.AutoRedraw = TruePicture1.BackColor = &H220000 '&HFFFFFF 'ctCenter = 0: ctBi = 1: ctV = 1 '参照系（位于中心的天体），缩放比列，速度ctSeeJ = 30: ctSeeBi = ctSeeJ / 90 '视点角度，视角比ctTrack = False '不显示运动轨迹（不是轨道）'添加按钮KjCls Command1KjAdd Command1, "始/停(&K)", ms_RunStop, "天体的运动状态：开始/暂停" KjAdd Command1, "进(&J)", ms_Step, "步进，运行到下一位置"KjAdd Command1, "退(&T)", ms_UnRun, "步进，后退到上一位置"KjAdd Command1, "迹(&A)", ms_Track, "运动轨迹：显示/隐藏"KjAdd Command1, "默(&D)", ms_DefSet, "将所有参数恢复为默认设置"KjAdd Command1, "参照系(&C)", ms_Center, "设置参照系（位于中心的天体）"KjAdd Command1, "天体(&X)", ms_Visible, "天体：显示/隐藏"KjAdd Command1, "名称(&M)", ms_ShowCap, "天体名称：显示/隐藏"KjAdd Command1, "轨道(&G)", ms_GuiDao, "天体运行轨道：显示/隐藏" KjAdd Command1, "速度(&V)", ms_V, "设置速度"KjAdd Command1, "视角(&L)", ms_SeeJ, "设置视点角度"KjAdd Command1, "缩放(&S)", ms_Bi, "设置缩放比列"'添加天体（演示比列状态下），半径以100 像素为标准'参数依次是：名称，父天体名称，天体半径，轨道长半轴，轨道偏心率，运动角速度，天体颜色，初始角度，彗星否ctDs = -1: ReDim ctD(0)AddCircle "太阳", "", 22, 2, 0, ctP * 0.008, RGB(255, 200, 0)AddCircle "水星", "", 5, 0.5, 0.206, ctP * 0.03, &H999999AddCircle "金星", "", 9, 0.8, 0.0068, ctP * 0.018, &H55AAAAAddCircle "地球", "", 10, 1.2, 0.0167, ctP * 0.01, RGB(0, 0, 255)AddCircle "月亮", "地球", 4, 0.2, 0, ctP * 0.06, &H888888AddCircle "嫦娥1号", "月亮", 2, 0.06, 0, ctP * 0.12, &HCCCCCCAddCircle "火星", "", 6, 1.8, 0.093, ctP * 0.005, &H1155FFAddCircle "火卫1", "火星", 3, 0.1, 0, ctP * 0.1, &HFFFF00, ctP * 2 * 0.3 AddCircle "火卫2", "火星", 3, 0.15, 0, ctP * 0.1, &H7777FF, ctP * 2 * 0.7 AddCircle "木星", "", 16, 3, 0.0483, ctP * 0.003, &HEEDDCCAddCircle "木卫1", "木星", 2, 0.25, 0, ctP * 0.05, &H883487, ctP * 2 * 0.2 AddCircle "木卫2", "木星", 2, 0.3, 0, ctP * 0.035, &H348888, ctP * 2 * 0.4 AddCircle "木卫3", "木星", 3, 0.35, 0, ctP * 0.03, &HAA34CC, ctP * 2 * 0.6 AddCircle "木卫4", "木星", 4, 0.45, 0, ctP * 0.02, &H888888, ctP * 2 * 0.8 AddCircle "土星", "", 14, 5, 0.056, ctP * 0.002, &H5599FFAddCircle "土卫6", "土星", 4, 0.25, 0, ctP * 0.055, &H99EEEEAddCircle "天王星", "", 12, 6.5, 0.0461, ctP * 0.0015, &HFFCCCC AddCircle "天卫3", "天王星", 3, 0.2, 0, ctP * 0.05, &H33FF88, ctP * 2 * 0.5 AddCircle "天卫4", "天王星", 3, 0.3, 0, ctP * 0.035, &HFF3311, ctP * 2 * 0.8 AddCircle "海王星", "", 12, 9, 0.0097, ctP * 0.001, &HFF7766AddCircle "海卫1", "海王星", 3, 0.25, 0, -ctP * 0.03, &H882388AddCircle "哈雷彗星", "", 2, 5.5, 0.83, ctP * 0.0012, &H777777, ctP * 1, TrueCall Form_ResizeEnd SubPrivate Sub Command1_Click(Index As Integer)Dim I As Long, J As Long, nStr As String, Zu As VariantDim nSel As Long, nAll As Long, nNo As LongctSet = Val(Command1(Index).Tag) '得到按钮标示KjCls mmFast '清除菜单'装载快捷菜单，并勾选选定项目Select Case ctSetCase ms_DefSet: Call Init: Run1: Exit Sub '默认设置Case ms_RunStop: Timer1.Enabled = Not Timer1.Enabled: Exit Sub '开始/暂停Case ms_Track: ctTrack = Not ctTrack: Picture1.Cls: Call Run1 '保留运动轨迹Case ms_Step '步进，前进到下一位置If Not Timer1.Enabled Then Run1 TrueTimer1.Enabled = FalseCase ms_UnRun '步进，后退到下一位置If Not Timer1.Enabled Then Run1 True, TrueTimer1.Enabled = FalseCase ms_Bi '缩放比列Zu = Array(0.1, 0.2, 0.3, 0.4, "-", 0.5, 0.6, 0.7, 0.8, 0.9, "-", 1, 1.2, 1.5, 1.8, 2, 3, 5, 8, 10)KjAddZu mmFast, Zu, ctBi, " 倍": GoTo Show1 '添加数组菜单，并勾选ctBi Case ms_SeeJ '视点角度Zu = Array("90 度（天球北极）", "80 度", "70 度", "60 度", "50 度", "45 度", "40 度", "30 度", "20 度", "15 度", "10 度", "5 度", "0 度（天球赤道）")KjAddZu mmFast, Zu, ctSeeJ: GoTo Show1 '添加数组菜单，并勾选ctSeeJ Case ms_V '速度Zu = Array(0.1, 0.2, 0.3, 0.4, "-", 0.5, 0.6, 0.7, 0.8, 0.9, "-", 1, 1.5, 2, 2.5, 3, 4, 5, 7.5, 10)KjAddZu mmFast, Zu, ctV, " 倍": GoTo Show1Case Else '装载天体名称For I = 0 To ctDsJ = Ji(I) '天体I 的级别KjAdd mmFast, "&" & I & " " & String(J * 2, " ") & ctD(I).CapNextEnd Select'勾选选定天体Select Case ctSetCase ms_Center: mmFast(ctCenter).Checked = True: GoTo Show1 '参照系（中心天体）Case ms_ShowCap '显示天体名称For I = 0 To ctDs: mmFast(I).Checked = ctD(I).ShowCap: NextCase ms_Visible '天体是否可见For I = 0 To ctDs: mmFast(I).Checked = ctD(I).Visible: NextCase ms_GuiDao '轨道For I = 0 To ctDs: mmFast(I).Checked = ctD(I).GuiDao: NextCase Else: Exit SubEnd SelectKjAdd mmFast, "-"nAll = KjAdd(mmFast, "全选", ms_All)nNo = KjAdd(mmFast, "全不选", ms_NoAll)For I = 0 To ctDsIf mmFast(I).Checked Then nSel = nSel + 1NextIf nSel = 0 Then mmFast(nNo).Checked = True: mmFast(nNo).Enabled = FalseIf nSel = ctDs + 1 Then mmFast(nAll).Checked = True: mmFast(nAll).Enabled = FalseShow1:Command1(Index).BackColor = &HFFCCCC '将选中按钮设置为淡蓝色Me.PopupMenu mFast, , Command1(Index).Left, Command1(Index).Top + Command1(Index).Height - 3Command1(Index).BackColor = Me.BackColorEnd SubPrivate Sub mmFast_Click(Index As Integer)'通过快捷菜单设置天体有关参数Dim nTag As MenuSet, I As Long, TF As BooleannTag = Val(mmFast(Index).Tag) '菜单标示：ms_All 全选，ms_NoAll 全不选Select Case ctSet 'ctSet：按钮标示，在Command1_Click 中设置Case ms_V '速度ctV = Val(mmFast(Index).Caption)Case ms_SeeJ '视点角度ctSeeJ = Val(mmFast(Index).Caption) '视点角度ctSeeBi = ctSeeJ / 90 '视角比For I = 0 To ctDs: ctD(I).xUp = 0: ctD(I).yUp = 0: Next Case ms_Bi '缩放比列ctBi = Val(mmFast(Index).Caption)For I = 0 To ctDs: ctD(I).xUp = 0: ctD(I).yUp = 0: Next Case ms_Center '参照系（中心天体）ctCenter = IndexFor I = 0 To ctDs: ctD(I).xUp = 0: ctD(I).yUp = 0: Next Case ms_ShowCap '显示名称If Index <= ctDs ThenctD(Index).ShowCap = Not ctD(Index).ShowCap ElseTF = nTag = ms_AllFor I = 0 To ctDs: ctD(I).ShowCap = TF: NextEnd IfCase ms_Visible '天体是否可见If Index <= ctDs ThenctD(Index).Visible = Not ctD(Index).VisibleElseTF = nTag = ms_AllFor I = 0 To ctDs: ctD(I).Visible = TF: NextEnd IfCase ms_GuiDao '轨道If Index <= ctDs ThenctD(Index).GuiDao = Not ctD(Index).GuiDaoElseTF = nTag = ms_AllFor I = 0 To ctDs: ctD(I).GuiDao = TF: NextEnd IfEnd SelectPicture1.ClsCall Run1End SubPrivate Sub AddCircle(nName As String, nFather As String, r As Long, a As Single, e As Single, V As Single, _Optional Se As Long = 255, Optional Jiao As Single, Optional IsHui As Boolean)'添加一个天体，参数依次是：' 名称，父天体名称，天体半径，轨道长半轴，轨道偏心率，运动角速度，天体颜色，初始角度，彗星否Dim I As Long, J As Longa = a * 100 '半径以100 像素为标准ctDs = ctDs + 1: ReDim Preserve ctD(ctDs)'设置父天体编号For I = 0 To ctDs - 1If LCase(ctD(I).Cap) = LCase(nFather) Then ctD(ctDs).Father = I: Exit For NextctD(ctDs).Cap = nName: ctD(ctDs).r = r: ctD(ctDs).a = actD(ctDs).c = a * e: ctD(ctDs).b = Sqr(a ^ 2 - ctD(ctDs).c ^ 2)ctD(ctDs).IsHui = IsHui: ctD(ctDs).V = V: ctD(ctDs).Se = SectD(ctDs).xUp = 0: ctD(ctDs).yUp = 0: ctD(ctDs).Visible = TruectD(ctDs).GuiDao = TrueRandomizeIf Jiao = 0 Then ctD(ctDs).Jiao = Rnd * ctP * 2 Else ctD(ctDs).Jiao = Jiao End SubPrivate Function KjAddZu(Kj, Zu As Variant, ByVal CheckStr As String, Optional SameStr As String)'添加一个数组菜单，并勾选标题为CheckStr 的条目Dim I As Long, J As Long, nCap As StringIf Left(CheckStr, 1) = "." Then CheckStr = "0" & CheckStrFor I = LBound(Zu) To UBound(Zu)nCap = Zu(I)If Left(nCap, 1) = "." Then nCap = "0" & nCapIf nCap = "-" Then J = KjAdd(Kj, nCap) Else J = KjAdd(Kj, nCap & SameStr) ' If LCase(CheckStr) = LCase(nCap) Then Kj(J).Checked = TrueIf Val(CheckStr) = Val(nCap) Then Kj(J).Checked = TrueNextEnd FunctionPrivate Function KjAdd(Kj, nCap As String, Optional nTag As String, Optional nNote As String) As Long'为数组控件添加一个成员，返回新添加的成员序号Dim I As LongI = Kj.Count - 1If Kj(I).Caption <> "" Then I = I + 1: Load Kj(I)On Error Resume NextKj(I).Checked = FalseKj(I).Caption = nCapKj(I).Tag = nTagKj(I).ToolTipText = nNoteKj(I).Visible = TrueKjAdd = IEnd FunctionPrivate Function KjCls(Kj) As Long'卸载数组控件的所有成员(0号除外)Dim I As LongFor I = Kj.Count - 1 To 1 Step -1Unload Kj(I)NextOn Error Resume NextKj(0).Caption = ""Kj(0).Checked = FalseEnd FunctionPrivate Function CapToNum(nCap As String) As Long'返回名称为nCap 的天体编号Dim I As LongFor I = 0 To ctDsIf LCase(ctD(I).Cap) = LCase(nCap) Then CapToNum = I: Exit FunctionNextCapToNum = -1End FunctionPrivate Function Ji(ByVal D As Long) As Long'返回天体级别（编号为D ）DoIf ctD(D).Father = 0 Then Exit DoD = ctD(D).Father: Ji = Ji + 1LoopEnd FunctionPrivate Sub Timer1_Timer()Run1 TrueEnd SubPrivate Sub Run1(Optional nRun As Boolean, Optional UnRun As Boolean) '显示一次运行的瞬时状态Dim wB As Single, hB As Single, X As Single, Y As Single, ZuY() As Long Dim I As Long, T As Long, Se As Long, r As SingleDim CenX As Single, CenY As Single, InD As Boolean, InD1 As Boolean'计算天体瞬时位置：相对与父天体的角度For I = 0 To ctDsIf nRun ThenIf UnRun Then X = ctD(I).Jiao - ctD(I).V * ctV Else X = ctD(I).Jiao + ctD(I).V * ctV'保证数值在0 到ctP*2 的范围内If X > ctP * 2 Then X = X - ctP * 2If X < 0 Then X = X + ctP * 2ctD(I).Jiao = XEnd If' If I = CapToNum("地球") Then Me.Caption = ctD(I).Jiao / ctP * 180 '调试代码****ctD(I).X = ctBi * (ctD(I).a * Sin(ctD(I).Jiao) + ctD(I).c)ctD(I).Y = ctBi * ctSeeBi * (ctD(I).b * Cos(ctD(I).Jiao))'加上父天体的位置ctD(I).X = ctD(I).X + ctD(ctD(I).Father).X: ctD(I).Y = ctD(I).Y +ctD(ctD(I).Father).YNext'移位参照系CenX = ctD(ctCenter).X: CenY = ctD(ctCenter).Y '中心天体位置For I = 0 To ctDsctD(I).X = CenX - ctD(I).X: ctD(I).Y = CenY - ctD(I).YNextSortY ZuY '将天体按Y 坐标排序，数组ZuY() 返回排序后的天体序号Picture1.Font.Size = 9: Picture1.ForeColor = &HFFFFFFwB = Picture1.ScaleWidth * 0.5 - ctBW: hB = Picture1.ScaleHeight * 0.5 - ctBW '可视区大小If Not ctTrack Then Picture1.Cls '保留轨迹，不擦除上次图像If ctBW > 0 Then Picture1.Line (-wB, -hB)-(wB, hB), , B '可见区方框，调试代码****For T = 0 To ctDs '按天体Y 坐标依次画出各天体I = ZuY(T) '天体实际编号X = ctD(I).X: Y = ctD(I).Y: r = ctBi * ctD(I).rIf r < 2 Then r = 2'画一个天体Call SubGuiDao(I) '画I 的卫星轨道：上半部分InD = Not (X + r < -wB Or X - r > wB Or Y + r < -hB Or Y - r > hB) '是否在可见区内If ctD(I).Visible And InD ThenIf ctD(I).IsHui Then Tail I, X, Y '画彗尾Picture1.FillColor = ctD(I).Se: Picture1.FillStyle = 0 '打开填充Picture1.Circle (X, Y), r, 0 '画天体Picture1.FillStyle = 1 '关闭填充End IfCall SubGuiDao(I, True) '画I 的卫星轨道：下半部分'显示天体名称If ctD(I).ShowCap ThenIf I = 0 ThenShowStr wB, hB, ctD(I).Cap, X, Y - Picture1.TextHeight("A") * 0.5, True, 0ElseShowStr wB, hB, ctD(I).Cap, X, Y + r + 3, TrueEnd IfEnd If'画运动轨迹：上一个点和当前点的连线：有一个在可见区内If ctTrack ThenInD1 = Not (ctD(I).xUp + r < -wB Or ctD(I).xUp - r > wB Or ctD(I).yUp + r < -hB Or ctD(I).yUp - r > hB)If (InD Or InD1) And ctD(I).xUp <> 0 And ctD(I).yUp <> 0 ThenIf ctBi < 1 Then Picture1.DrawWidth = 1 Else Picture1.DrawWidth = ctBi * 2 Picture1.Line (X, Y)-(ctD(I).xUp, ctD(I).yUp), ctD(I).SePicture1.DrawWidth = 1End IfEnd If'记忆上次位置ctD(I).xUp = X: ctD(I).yUp = YNextEnd SubPrivate Sub Tail(I As Long, X As Single, Y As Single)'画天体I 的彗尾Dim x0 As Single, y0 As Single, S As SingleDim x1 As Single, y1 As Single, J As Single'无压缩时的位置x0 = ctD(I).a * Sin(ctD(I).Jiao): y0 = ctD(I).b * Cos(ctD(I).Jiao)J = ctBi * Sqr((x0 + ctD(I).c) ^ 2 + y0 ^ 2) '与焦点（即：父天体）距离S = ctBi * (ctD(I).a - ctD(I).c) ^ 2 / J - (ctD(I).a - ctD(I).c) / 5 '彗发长度：近日距离4/5If S < 0 Then Exit SubS = S * ctBiIf S > Picture1.ScaleWidth Then S = Picture1.ScaleWidthx1 = ctD(ctD(I).Father).X: y1 = ctD(ctD(I).Father).Y '父天体位置x1 = S / J * (X - x1): y1 = S / J * (Y - y1)Picture1.DrawMode = 14: Picture1.DrawWidth = ctD(I).r * 3 * ctBi + 1Picture1.Line (X, Y)-Step(x1, y1), &H999999Picture1.Line (X, Y)-Step(x1, y1), &H999999Picture1.DrawWidth = 1: Picture1.DrawMode = 13End SubPrivate Sub ShowStr(wB As Single, hB As Single, nStr As String, ByVal X As Single, ByVal Y As Single, Optional CenLR As Boolean, Optional Se As Long = -1)'显示字符wB,hB：可见区边界CenLR = T：左右居中Dim W As Single, H As Single, nSe As LongW = Picture1.TextWidth(nStr): H = Picture1.TextHeight(nStr)If CenLR Then X = X - W * 0.5If X < -wB - W Or X > wB Or Y < -hB - H Or Y > hB Then Exit SubPicture1.CurrentX = X: Picture1.CurrentY = Y: Picture1.Print nStrIf Se = -1 Then Exit SubnSe = Picture1.ForeColor: Picture1.ForeColor = SePicture1.CurrentX = X + 1: Picture1.CurrentY = Y + 1Picture1.Print nStrPicture1.ForeColor = nSeEnd SubPrivate Sub SortY(ZuY() As Long)'将天体按Y 坐标排序，数组ZuY() 返回排序后的天体序号Dim I As Long, J As Long, K As Long, S As Long, y1 As Single Dim Y() As SingleReDim Y(0 To ctDs) 'Y() 用于视角为0 的情况For I = 0 To ctDsIf ctSeeBi = 0 ThenIf ctD(I).Jiao > ctP * 0.5 And ctD(I).Jiao < ctP * 1.5 ThenY(I) = ctD(I).bElseY(I) = -ctD(I).bEnd IfY(I) = Y(I) + Y(ctD(I).Father) '加上父天体的Y 坐标ElseY(I) = ctD(I).YEnd IfNextReDim ZuY(0 To ctDs)ZuY(0) = 0For I = 1 To ctDsy1 = Y(I)For J = 0 To I - 1If y1 < Y(ZuY(J)) ThenFor K = I - 1 To J Step -1 '下移动已排序数组J 之后的ZuY(K + 1) = ZuY(K)NextZuY(J) = I: GoTo Next1End IfNextZuY(I) = INext1:NextEnd SubPrivate Sub GetXY(ByVal I As Long, Jiao As Single, CenX As Single, CenY As Single, X As Single, Y As Single)'获取某天体I 在Jiao 位置的绝对位置'CenX，CenY：父天体的位置X = CenX - ctBi * (ctD(I).a * Sin(Jiao) + ctD(I).c)Y = CenY - ctBi * ctSeeBi * ctD(I).b * Cos(Jiao)End SubPrivate Sub SubGuiDao(I As Long, Optional IsDown As Boolean)'画天体I 的卫星轨道的一半Dim W As LongFor W = 0 To ctDsIf W <> I And ctD(W).GuiDao And ctD(W).Father = I Then GuiDao W, IsDown NextEnd SubPrivate Sub GuiDao(I As Long, Optional IsDown As Boolean)'画轨道Dim J As Single, X As Single, Y As Single, CenX As Single, CenY As Single Dim W1 As Single, H1 As Single, xUp As Single, yUp As Single, Is2 As BooleanDim InD As Boolean, InUpD As Boolean, J1 As Single, J2 As SinglePicture1.DrawWidth = 1W1 = Picture1.ScaleWidth * 0.5 - ctBW: H1 = Picture1.ScaleHeight * 0.5 - ctBWCenX = ctD(ctD(I).Father).X: CenY = ctD(ctD(I).Father).Y '父天体的位置If IsDown ThenJ1 = ctP * 0.5: J2 = ctP * 1.5 '下半部分ElseJ1 = ctP * 1.5: J2 = ctP * 2.5 '上半部分End IfFor J = J1 To J2 Step 0.05Call GetXY(I, J, CenX, CenY, X, Y)InD = Not (X < -W1 Or X > W1 Or Y < -H1 Or Y > H1) '点1是否在可见区内If Is2 And (InD Or InUpD) Then Picture1.Line (X, Y)-(xUp, yUp), ctD(I).SexUp = X: yUp = Y: InUpD = InD: Is2 = TrueNext'末点：将轨道封闭Call GetXY(I, J2, CenX, CenY, X, Y)InD = Not (X < -W1 Or X > W1 Or Y < -H1 Or Y > H1)If InD Or InUpD Then Picture1.Line (X, Y)-(xUp, yUp), ctD(I).Se End Sub当前位置：首页> VB 小程序> 太阳系行星轨道及运行动画演示。