Visual Basic Graphics Programming (2nd Edition)/Visual Basic Graphics Programming 2nd Edition.iso/OldSrc/CH11/SRC/DEPTH2.FRM

Text File | 1997-01-17 | 10KB | 395 lines

VERSION 4.00
Begin VB.Form DepthSortForm
   Appearance      =   0  'Flat
   BackColor       =   &H00C0C0C0&
   Caption         =   "Depth Sort"
   ClientHeight    =   5685
   ClientLeft      =   1230
   ClientTop       =   870
   ClientWidth     =   6030
   BeginProperty Font
      name            =   "MS Sans Serif"
      charset         =   1
      weight          =   700
      size            =   8.25
      underline       =   0   'False
      italic          =   0   'False
      strikethrough   =   0   'False
   EndProperty
   ForeColor       =   &H80000008&
   Height          =   6375
   KeyPreview      =   -1  'True
   Left            =   1170
   LinkTopic       =   "Form1"
   ScaleHeight     =   5685
   ScaleWidth      =   6030
   Top             =   240
   Width           =   6150
   Begin VB.TextBox PhiText
      Height          =   285
      Left            =   3600
      TabIndex        =   6
      Text            =   "0.7854"
      Top             =   5400
      Width           =   855
   End
   Begin VB.TextBox ThetaText
      Height          =   285
      Left            =   2040
      TabIndex        =   4
      Text            =   "25.7611"
      Top             =   5400
      Width           =   855
   End
   Begin VB.TextBox RText
      Height          =   285
      Left            =   480
      TabIndex        =   2
      Text            =   "10.0000"
      Top             =   5400
      Width           =   855
   End
   Begin VB.PictureBox Pict
      AutoRedraw      =   -1  'True
      BackColor       =   &H00C0C0C0&
      Height          =   5295
      Left            =   0
      ScaleHeight     =   -14
      ScaleLeft       =   -7
      ScaleMode       =   0  'User
      ScaleTop        =   7
      ScaleWidth      =   15.926
      TabIndex        =   0
      Top             =   0
      Width           =   6015
   End
   Begin MSComDlg.CommonDialog LoadDialog
      Left            =   4920
      Top             =   5280
      _version        =   65536
      _extentx        =   847
      _extenty        =   847
      _stockprops     =   0
   End
   Begin VB.Label Label1
      Caption         =   "Phi"
      Height          =   255
      Index           =   2
      Left            =   3240
      TabIndex        =   5
      Top             =   5400
      Width           =   375
   End
   Begin VB.Label Label1
      Caption         =   "Theta"
      Height          =   255
      Index           =   1
      Left            =   1440
      TabIndex        =   3
      Top             =   5400
      Width           =   495
   End
   Begin VB.Label Label1
      Caption         =   "R"
      Height          =   255
      Index           =   0
      Left            =   240
      TabIndex        =   1
      Top             =   5400
      Width           =   255
   End
   Begin VB.Menu mnuFile
      Caption         =   "&File"
      Begin VB.Menu mnuFileLoad
         Caption         =   "&Load..."
         Shortcut        =   ^L
      End
      Begin VB.Menu mnuFileSep
         Caption         =   "-"
      End
      Begin VB.Menu mnuFileExit
         Caption         =   "E&xit"
      End
   End
End
Attribute VB_Name = "DepthSortForm"
Attribute VB_Creatable = False
Attribute VB_Exposed = False

Option Explicit

' Location of viewing eye.
Dim EyeR As Single
Dim EyeTheta As Single
Dim EyePhi As Single

Const Dtheta = PI / 20
Const Dphi = PI / 20
Const Dr = 1

' Location of focus point.
Const FocusX = 0#
Const FocusY = 0#
Const FocusZ = 0#

Dim Projector(1 To 4, 1 To 4) As Single

Dim ThePicture As ObjPicture

Dim ShowingParameters As Boolean

' *******************************************************
' Rotate the points in the cube and draw the cube.
' *******************************************************
Private Sub DrawData(pic As Object)
Dim x As Single
Dim y As Single
Dim z As Single
Dim edge_pen As Long
Dim old_pen As Long
Dim fill_brush As Long
Dim old_brush As Long
Dim status As Long
Dim t1(1 To 4, 1 To 4) As Single
Dim t2(1 To 4, 1 To 4) As Single
Dim T12(1 To 4, 1 To 4) As Single
Dim T123(1 To 4, 1 To 4) As Single
Dim pt As Point3D

    MousePointer = vbHourglass

    ' Prevent overflow errors when drawing lines
    ' too far out of bounds.
    On Error Resume Next

    ' Cull backfaces.
    ThePicture.Culled = False
    m3SphericalToCartesian EyeR, EyeTheta, EyePhi, x, y, z
    ThePicture.Cull x, y, z

    ' Clip faces behind the center of projection.
    ThePicture.ClipEye EyeR

    ' Transform coordinates into pixels.
    m3Scale t1, _
        Pict.ScaleX(1, Pict.ScaleMode, vbPixels), _
        Pict.ScaleY(1, Pict.ScaleMode, vbPixels), _
        1
    m3Translate t2, _
        -Pict.ScaleX(Pict.ScaleLeft, Pict.ScaleMode, vbPixels), _
        -Pict.ScaleY(Pict.ScaleTop, Pict.ScaleMode, vbPixels), _
        0
    m3MatMultiply T12, t1, t2
    m3MatMultiplyFull T123, Projector, T12

    ' Transform the points.
    ThePicture.ApplyFull T123

    ' Clear the screen. We must do this before
    ' selecting the pen and brush since Cls resets
    ' the pen and brush to default values.
    pic.Cls

    ' Get a pen and brush.
    edge_pen = CreatePen(PS_SOLID, pic.DrawWidth, pic.ForeColor)
    old_pen = SelectObject(pic.hdc, edge_pen)
    fill_brush = CreateSolidBrush(pic.BackColor)
    old_brush = SelectObject(pic.hdc, fill_brush)

    ' Display the data.
    ThePicture.DrawOrdered pic, EyeR

    pic.Refresh

    ' Restore the old pen and brush.
    edge_pen = SelectObject(pic.hdc, old_pen)
    fill_brush = SelectObject(pic.hdc, old_brush)
    status = DeleteObject(edge_pen)
    status = DeleteObject(fill_brush)

    ' Display the viewing parameters.
    ShowViewingParameters

    MousePointer = vbDefault
End Sub

Sub ShowViewingParameters()
    ShowingParameters = True

    RText.Text = Format$(EyeR, "0.0000")
    ThetaText.Text = Format$(EyeTheta, "0.0000")
    PhiText.Text = Format$(EyePhi, "0.0000")

    RText.Refresh
    ThetaText.Refresh
    PhiText.Refresh

    ShowingParameters = False
End Sub



Private Sub Form_KeyDown(KeyCode As Integer, Shift As Integer)
    Select Case KeyCode
        Case vbKeyLeft
            EyeTheta = EyeTheta - Dtheta

        Case vbKeyRight
            EyeTheta = EyeTheta + Dtheta

        Case vbKeyUp
            EyePhi = EyePhi - Dphi

        Case vbKeyDown
            EyePhi = EyePhi + Dphi

        Case Else
            Exit Sub
    End Select

    m3PProject Projector, m3Perspective, EyeR, EyePhi, EyeTheta, FocusX, FocusY, FocusZ, 0, 1, 0
    DrawData Pict
End Sub


Private Sub Form_KeyPress(KeyAscii As Integer)
    Select Case KeyAscii
        Case Asc("+")
            EyeR = EyeR + Dr

        Case Asc("-")
            EyeR = EyeR - Dr

        Case Else
            Exit Sub
    End Select

    m3PProject Projector, m3Perspective, EyeR, EyePhi, EyeTheta, FocusX, FocusY, FocusZ, 0, 1, 0
    DrawData Pict
End Sub

Private Sub Form_Load()
    ' Initialize the eye position.
    EyeR = 20
    EyeTheta = PI * 0.2
    EyePhi = PI * 0.05

    ' Initialize the projection transformation.
    m3PProject Projector, m3Perspective, EyeR, EyePhi, EyeTheta, FocusX, FocusY, FocusZ, 0, 1, 0

    ' Create the data.
    CreateData

    ' Project and draw the data.
    DrawData Pict
End Sub

' ***********************************************
' Create some axes initially.
' ***********************************************
Sub CreateData()
Dim pline As ObjPolyline

    Set ThePicture = New ObjPicture
    Set pline = New ObjPolyline
    ThePicture.Objects.Add pline

    pline.AddSegment 0, 0, 0, 5, 0, 0
    pline.AddSegment 0, 0, 0, 0, 5, 0
    pline.AddSegment 0, 0, 0, 0, 0, 5
End Sub
Private Sub mnuFileExit_Click()
    Unload Me
End Sub


Private Sub mnuFileLoad_Click()
Dim fname As String
Dim filenum As Integer
Dim txt As String
Dim xmin As Single
Dim ymin As Single
Dim xmax As Single
Dim ymax As Single

    ' Allow the user to pick a file.
    On Error Resume Next
    LoadDialog.filename = "*.APF"
    LoadDialog.ShowOpen
    LoadDialog.Flags = cdlOFNFileMustExist + cdlOFNHideReadOnly
    If Err.Number = cdlCancel Then
        Unload LoadDialog
        Exit Sub
    ElseIf Err.Number <> 0 Then
        Unload LoadDialog
        Beep
        MsgBox "Error selecting file.", , vbExclamation
        Exit Sub
    End If
    On Error GoTo 0

    fname = LoadDialog.filename
    LoadDialog.InitDir = Left$(fname, Len(fname) _
        - Len(LoadDialog.FileTitle) - 1)

    ' Clear the picture.
    Set ThePicture = Nothing

    ' Open the file.
    filenum = FreeFile
    Open fname For Input As #filenum

    ' Make sure it's an Object Picture File.
    Input #filenum, txt
    If txt <> "3D APF PICTURE" Then
        Close filenum
        Caption = "Show APF"
        Beep
        MsgBox "Error reading file """ & fname & """.", , vbExclamation
        Exit Sub
    End If

    ' Read the picture.
    Set ThePicture = New ObjPicture
    ThePicture.FileInput filenum

    ' Close the file.
    Close filenum

    Caption = "Show APF [" & LoadDialog.FileTitle & "]"

    ' Refresh the display.
    DrawData Pict
End Sub




Private Sub PhiText_Change()
    If ShowingParameters Then Exit Sub
    EyePhi = CSng(PhiText.Text)
    m3PProject Projector, m3Perspective, EyeR, EyePhi, EyeTheta, FocusX, FocusY, FocusZ, 0, 1, 0
    DrawData Pict
End Sub


Private Sub RText_Change()
    If ShowingParameters Then Exit Sub
    EyeR = CSng(RText.Text)
    m3PProject Projector, m3Perspective, EyeR, EyePhi, EyeTheta, FocusX, FocusY, FocusZ, 0, 1, 0
    DrawData Pict
End Sub

Private Sub ThetaText_Change()
    If ShowingParameters Then Exit Sub
    EyeTheta = CSng(ThetaText.Text)
    m3PProject Projector, m3Perspective, EyeR, EyePhi, EyeTheta, FocusX, FocusY, FocusZ, 0, 1, 0
    DrawData Pict
End Sub