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Opengl text problem
Post by RobM on Aug 29th, 2017, 05:30am

I have been able to get text to display in an Opengl window (not as easy as it may sound!) but for some reason the spaces between the words are missing. Any ideas?

Code:
    'http://nehe.gamedev.net/tutorial/bitmap_fonts/17002/
    nomainwin
    struct PFD,   Size as word, Version as word, Flags as long,_
        PixelType as char[1], ColorBits as char[1], RedBits as char[1],_
        RedShift as char[1], GreenBits as char[1], GreenShift as char[1],_
        BlueBits as char[1], BlueShift as char[1], AlphaBits as char[1],_
        AlphaShift as char[1],AccumBits as char[1], AccumRedBits as char[1],_
        AccumGreenBits as char[1], AccumBlueBits as char[1], AccumAlphaBits as char[1],_
        DepthBits as char[1], StencilBits as char[1], AuxBuffers as char[1],_
        LayerType as char[1], Reserved as char[1], LayerMask as long,_
        VisibleMask as long, DamageMask as long
    PFD.Version.struct=1:PFD.ColorBits.struct=24
    PFD.DepthBits.struct=16:PFD.Size.struct=len(PFD.struct)
    PFD.Flags.struct=37:GlColorBufferBit=16384
    open "opengl32.dll" for dll as #gl
    open "glu32.dll" for dll as #glu
    open "oleaut32.dll" for dll as #oleaut32
    WindowWidth=500:WindowHeight=500
    UpperLeftX=1:UpperLeftY=1
    open "Triangle" for window_nf as #main
    print #main,"trapclose [quit]"
    MainH=hwnd(#main)
    calldll #user32,"GetDC", MainH as ulong, MainDC as ulong
    calldll #gdi32,"ChoosePixelFormat", MainDC as ulong, PFD as struct, ret as long
    calldll #gdi32, "SetPixelFormat", MainDC as ulong, ret as long, PFD as struct, t as long
    calldll #gl,"wglCreateContext", MainDC as ulong, GLContext as ulong
    calldll #gl,"wglMakeCurrent", MainDC as ulong, GLContext as ulong, ret as long
    calldll #gl,"glClear", GlColorBufferBit as long,  ret as long
    'calldll #gl,"glRotated", 0 as double, 0 as double, 0 as double, 0 as double, ret as long
    calldll #gl,"glBegin", 4 as long, ret as long
    calldll #gl,"glColor3d", 0 as double, 0 as double, 255 as double, ret as long
    calldll #gl,"glVertex3i", -1 as long, -1 as long, 0 as long, ret as long
    calldll #gl,"glColor3d", 255 as double, 0 as double, 0 as double, ret as long
    calldll #gl,"glVertex3i", 0 as long, 1 as long, 0 as long, ret as long
    calldll #gl,"glColor3d", 0 as double, 255 as double, 0 as double, ret as long
    calldll #gl,"glVertex3i", 1 as long, -1 as long, 0 as long, ret as long
    calldll #gl,"glEnd", ret as void
    base=glGenLists(96)
    fontH=CreateFont(-22,"Times New Roman")
    calldll #gdi32,"SelectObject",_
        MainDC as ulong,_ 'handle of dc
        fontH as ulong,_ 'handle of brush
        oldfont as ulong
    calldll #gl,"wglUseFontBitmapsA",_
        MainDC as ulong,_
        32 as ulong,_
        96 as ulong,_
        base as ulong,_
        ret as long
    calldll #gdi32,"DeleteObject",fontH as ulong,r as ulong
    calldll #gl,"glColor3d", 0 as double, 0 as double, 0 as double, ret as long
    x=R4(-.35)
    y=R4(-.25)
    calldll #gl,"glRasterPos2f",_
       x as ulong,_
       y as ulong,_
       ret as long
    GL.LIST.BIT = 131072
    calldll #gl,"glPushAttrib",_
      GL.LIST.BIT as long,_
      ret as long
     gllistbase=base - 32
     calldll #gl,"glListBase",_
       gllistbase as long,_
       ret as long
    text$="My spaces are missing :("
    length=len(text$)
    GL.UNSIGNED.BYTE = 5121
    calldll #gl,"glCallLists",_
       length as long,_
       GL.UNSIGNED.BYTE as long,_
       text$ as ptr,_
       ret as long
    calldll #gl,"glPopAttrib", ret as long
    calldll #gdi32,"SwapBuffers", MainDC as ulong, ret as long
    wait
[quit]
    calldll #gl,"wglMakeCurrent", 0 as ulong, 0 as ulong, ret as long
    calldll #gl,"wglDeleteContext", GLContext as ulong, ret as long
    calldll #user32, "ReleaseDC", MainH as ulong, MainDC as ulong,ret as long
    close #main
    close #glu
    close #gl
    close #oleaut32
    end
function glGenLists(num)
    CALLDLL #gl , "glGenLists" ,_
      num AS long ,_
      glGenLists AS void
END function
function CreateFont(fontheight,facename$)
    calldll #gdi32, "CreateFontA",_
      fontheight as long, fontwidth as long,_
      escapement as long, orientation as long,_
      _FW_NORMAL as long, italic as long,_
      underline as long, strikeout as long,_
      CharSet as long, OutputPrecision as long,_
      ClipPrecision as long, Quality as long,_
      PitchAndFamily as long,facename$ as PTR,_
      CreateFont as ulong 'returns handle to font
end function
FUNCTION R4( R8 )
    STRUCT local1 ,_
      R4 AS ULong
    CALLDLL #oleaut32 , "VarR4FromR8" ,_
      R8 AS Double ,_
      local1 AS STRUCT ,_
      ret AS Long
    R4 = local1.R4.struct
END FUNCTION


User Image
Re: Opengl text problem
Post by Richard Russell on Aug 29th, 2017, 08:38am

on Aug 29th, 2017, 05:30am, RobM wrote:
Any ideas?

Try this (based on the example at MSDN):

Code:
   nomainwin
    struct PFD,   Size as word, Version as word, Flags as long,_
        PixelType as char[1], ColorBits as char[1], RedBits as char[1],_
        RedShift as char[1], GreenBits as char[1], GreenShift as char[1],_
        BlueBits as char[1], BlueShift as char[1], AlphaBits as char[1],_
        AlphaShift as char[1],AccumBits as char[1], AccumRedBits as char[1],_
        AccumGreenBits as char[1], AccumBlueBits as char[1], AccumAlphaBits as char[1],_
        DepthBits as char[1], StencilBits as char[1], AuxBuffers as char[1],_
        LayerType as char[1], Reserved as char[1], LayerMask as long,_
        VisibleMask as long, DamageMask as long
    PFD.Version.struct=1:PFD.ColorBits.struct=24
    PFD.DepthBits.struct=16:PFD.Size.struct=len(PFD.struct)
    PFD.Flags.struct=37:GlColorBufferBit=16384
    open "opengl32.dll" for dll as #gl
    open "glu32.dll" for dll as #glu
    open "oleaut32.dll" for dll as #oleaut32
    WindowWidth=500:WindowHeight=500
    UpperLeftX=1:UpperLeftY=1
    open "Triangle" for window_nf as #main
    print #main,"trapclose [quit]"
    MainH=hwnd(#main)
    calldll #user32,"GetDC", MainH as ulong, MainDC as ulong
    calldll #gdi32,"ChoosePixelFormat", MainDC as ulong, PFD as struct, ret as long
    calldll #gdi32, "SetPixelFormat", MainDC as ulong, ret as long, PFD as struct, t as long
    calldll #gl,"wglCreateContext", MainDC as ulong, GLContext as ulong
    calldll #gl,"wglMakeCurrent", MainDC as ulong, GLContext as ulong, ret as long
    calldll #gl,"glClear", GlColorBufferBit as long,  ret as long
    'calldll #gl,"glRotated", 0 as double, 0 as double, 0 as double, 0 as double, ret as long
    calldll #gl,"glBegin", 4 as long, ret as long
    calldll #gl,"glColor3d", 0 as double, 0 as double, 255 as double, ret as long
    calldll #gl,"glVertex3i", -1 as long, -1 as long, 0 as long, ret as long
    calldll #gl,"glColor3d", 255 as double, 0 as double, 0 as double, ret as long
    calldll #gl,"glVertex3i", 0 as long, 1 as long, 0 as long, ret as long
    calldll #gl,"glColor3d", 0 as double, 255 as double, 0 as double, ret as long
    calldll #gl,"glVertex3i", 1 as long, -1 as long, 0 as long, ret as long
    calldll #gl,"glEnd", ret as void
    base=glGenLists(255)
    fontH=CreateFont(-22,"Times New Roman")
    calldll #gdi32,"SelectObject",_
        MainDC as ulong,_ 'handle of dc
        fontH as ulong,_ 'handle of brush
        oldfont as ulong
    calldll #gl,"wglUseFontBitmapsA",_
        MainDC as ulong,_
        0 as ulong,_
        255 as ulong,_
        base as ulong,_
        ret as long
    calldll #gdi32,"DeleteObject",fontH as ulong,r as ulong
    calldll #gl,"glColor3d", 0 as double, 0 as double, 0 as double, ret as long
    x=R4(-.50)
    y=R4(-.25)
    calldll #gl,"glRasterPos2f",_
       x as ulong,_
       y as ulong,_
       ret as long
    GL.LIST.BIT = 131072
    calldll #gl,"glPushAttrib",_
      GL.LIST.BIT as long,_
      ret as long
     calldll #gl,"glListBase",_
       base as long,_
       ret as long
    text$="My spaces are not missing :)"
    length=len(text$)
    GL.UNSIGNED.BYTE = 5121
    calldll #gl,"glCallLists",_
       length as long,_
       GL.UNSIGNED.BYTE as long,_
       text$ as ptr,_
       ret as long
    calldll #gl,"glPopAttrib", ret as long
    calldll #gdi32,"SwapBuffers", MainDC as ulong, ret as long
    wait
[quit]
    calldll #gl,"wglMakeCurrent", 0 as ulong, 0 as ulong, ret as long
    calldll #gl,"wglDeleteContext", GLContext as ulong, ret as long
    calldll #user32, "ReleaseDC", MainH as ulong, MainDC as ulong,ret as long
    close #main
    close #glu
    close #gl
    close #oleaut32
    end
function glGenLists(num)
    CALLDLL #gl , "glGenLists" ,_
      num AS long ,_
      glGenLists AS void
END function
function CreateFont(fontheight,facename$)
    calldll #gdi32, "CreateFontA",_
      fontheight as long, fontwidth as long,_
      escapement as long, orientation as long,_
      _FW_NORMAL as long, italic as long,_
      underline as long, strikeout as long,_
      CharSet as long, OutputPrecision as long,_
      ClipPrecision as long, Quality as long,_
      PitchAndFamily as long,facename$ as PTR,_
      CreateFont as ulong 'returns handle to font
end function
FUNCTION R4( R8 )
    STRUCT local1 ,_
      R4 AS ULong
    CALLDLL #oleaut32 , "VarR4FromR8" ,_
      R8 AS Double ,_
      local1 AS STRUCT ,_
      ret AS Long
    R4 = local1.R4.struct
END FUNCTION


Richard.
Re: Opengl text problem
Post by RobM on Aug 29th, 2017, 3:42pm

Thanks Richard!

I am guessing the Nehe sample wouldn't run properly if it were compiled. Looks like it doesn't load enough characters.