C# Signature:
[DllImport("opengl32", EntryPoint = "wglUseFontOutlines", CallingConvention=CallingConvention.Winapi)]
public static extern bool wglUseFontOutlines(
IntPtr hDC,
[MarshalAs(UnmanagedType.U4)] UInt32 first,
[MarshalAs(UnmanagedType.U4)] UInt32 count,
[MarshalAs(UnmanagedType.U4)] UInt32 listBase,
[MarshalAs(UnmanagedType.R4)] Single deviation,
[MarshalAs(UnmanagedType.R4)] Single extrusion,
[MarshalAs(UnmanagedType.I4)] Int32 format,
[Out] Gdi.GLYPHMETRICSFLOAT[] lpgmf);
[StructLayout(LayoutKind.Sequential, CharSet=CharSet.Auto)]
public struct GLYPHMETRICSFLOAT
{
public Single gmfBlackBoxX;
public Single gmfBlackBoxY;
public POINTFLOAT gmfptGlyphOrigin;
public Single gmfCellIncX;
public Single gmfCellIncY;
}
public struct POINTFLOAT
{
public Single x;
public Single y;
}
VB Signature:
Declare Function wglUseFontOutlines Lib "opengl32.dll" (TODO) As TODO
User-Defined Types:
None.
Notes:
None.
Tips & Tricks:
Seems to work for Win98, WinNT, WinXP, Win2K, and Win2003.
Sample Code:
public Gdi.GLYPHMETRICSFLOAT[] gmf = null;
public UInt32 FontBase = 0;
IntPtr _OldFontH = IntPtr.Zero;
public void Individual_OpenGLInit( System.Windows.Forms.PaintEventArgs pe )
{
#region Generate GDI WGL FONT OUTLINES
try
{
gmf = new Gdi.GLYPHMETRICSFLOAT[256];
IntPtr dc = pe.Graphics.GetHdc();
System.Drawing.Font font =
new Font(
"Verdana",
9F,
System.Drawing.FontStyle.Regular,
System.Drawing.GraphicsUnit.Point,
((System.Byte)(0)));
FontBase = GL.glGenLists(256);
IntPtr fontH = font.ToHfont();
_OldFontH = Gdi.SelectObject(dc, fontH);
WGL.wglUseFontOutlines(
dc,
0,
255,
FontBase,
0,
0.2f,
WGL.WGL_FONT_POLYGONS,
gmf);
pe.Graphics.ReleaseHdc(dc);
}
catch
{
Console.Error.WriteLine("Unable to initialize fonts [FAILED]");
}
#endregion
}
public void Individual_OpenGLDeinit( System.Windows.Forms.PaintEventArgs pe )
{
#region Deinit GDI WGL FONT OUTLINES
try
{
if(gmf != null)
gmf = null;
IntPtr dc = pe.Graphics.GetHdc();
IntPtr disposeFontH = Gdi.SelectObject(dc, _OldFontH);
Gdi.DeleteObject(disposeFontH);
GL.glDeleteLists(FontBase, 256);
pe.Graphics.ReleaseHdc(dc);
}
catch
{
Console.Error.WriteLine("Unable to de-initialize fonts [FAILED]");
}
#endregion
}
public void glPrint(String outputString,Int32 x1, Int32 y1, Int32 x2,
Int32 y2)
{
if(outputString == null)
return;
if(outputString.Length == 0)
return;
GL.glPushMatrix();
Single scale = 15.0f;
GL.glMatrixMode(GL.GL_MODELVIEW);
GL.glTranslatef(x1,y1,0);
GL.glScalef(scale, -scale, scale);
GL.glPushAttrib(GL.GL_LIST_BIT);
GL.glListBase(m_Parent.m_TagcWorkspaceControl.FontBase);
// Find width of string
Int32 i=0;
float width = 0;
for( ; i<outputString.Length; i++)
{
width +=
m_Parent.m_TagcWorkspaceControl.gmf[ outputString[i] ] .
gmfCellIncX * scale;
if((x1+width)>=x2)
break;
if((y1+
m_Parent.m_TagcWorkspaceControl.gmf[ outputString[i] ] .
gmfCellIncY * scale)>=y2)
break;
}
// Print the string if there is room
if(i>0)
GL.glCallLists(i, GL.GL_UNSIGNED_BYTE, outputString);
GL.glPopAttrib();
GL.glPopMatrix();
}
public Int32 getPrintWidth(String outputString)
{
if(outputString == null)
return 0;
if(outputString.Length == 0)
return 0;
Single scale = 15.0f;
// Find width of string
float width = 0;
for(Int32 i=0; i<outputString.Length; i++)
{
width +=
m_Parent.m_TagcWorkspaceControl.gmf[ outputString[i] ] .
gmfCellIncX * scale;
}
return (Int32)Math.Ceiling(width);
}
Alternative Managed API:
The Tao Framework (open source and free: get it at http://www.taoframework.com/ ) wraps all the OpenGL functions (as well as other multimedia libraries) for your VB and C# programming pleasure.
