private FontOutlineEntry CreateFontOutlineEntry(OpenGL gl, string faceName,
float deviation, float extrusion, FontOutlineFormat fontOutlineFormat)
{
// Make the OpenGL instance current.
gl.MakeCurrent();
// Create the font based on the face name.
var hFont = Win32.CreateFont(12, 0, 0, 0, Win32.FW_DONTCARE, 0, 0, 0, Win32.DEFAULT_CHARSET,
Win32.OUT_OUTLINE_PRECIS, Win32.CLIP_DEFAULT_PRECIS, Win32.CLEARTYPE_QUALITY, Win32.VARIABLE_PITCH, faceName);
// Select the font handle.
var hOldObject = Win32.SelectObject(gl.RenderContextProvider.DeviceContextHandle, hFont);
// Create the list base.
var listBase = gl.GenLists(1);
// Create space for the glyph metrics.
var glyphMetrics = new GLYPHMETRICSFLOAT[255];
// Create the font bitmaps.
bool result = Win32.wglUseFontOutlines(gl.RenderContextProvider.DeviceContextHandle, 0, 255, listBase,
deviation, extrusion, (int)fontOutlineFormat, glyphMetrics);
// Reselect the old font.
Win32.SelectObject(gl.RenderContextProvider.DeviceContextHandle, hOldObject);
// Free the font.
Win32.DeleteObject(hFont);
// If we failed to create the font outlines, bail out now.
if (result == false)
{
return(null);
}
// Create the font bitmap entry.
var foe = new FontOutlineEntry()
{
HDC = gl.RenderContextProvider.DeviceContextHandle,
HRC = gl.RenderContextProvider.RenderContextHandle,
FaceName = faceName,
ListBase = listBase,
ListCount = 255,
Deviation = deviation,
Extrusion = extrusion,
FontOutlineFormat = fontOutlineFormat,
GlyphMetrics = glyphMetrics
};
// Add the font bitmap entry to the internal list.
fontOutlineEntries.Add(foe);
return(foe);
}
/// <summary>
/// Draws the text.
/// </summary>
/// <param name="gl">The gl.</param>
/// <param name="faceName">Name of the face.</param>
/// <param name="fontSize">Size of the font.</param>
/// <param name="deviation">The deviation.</param>
/// <param name="extrusion">The extrusion.</param>
/// <param name="text">The text.</param>
/// <param name="glyphMetrics"> </param>
public void DrawText(OpenGL gl, string faceName, float fontSize, float deviation, float extrusion, string text, out GLYPHMETRICSFLOAT[] glyphMetrics)
{
// Get the font size in pixels.
var fontHeight = (int)(fontSize * (16.0f / 12.0f));
// Do we have a font bitmap entry for this OpenGL instance and face name?
var result = (from fbe in fontOutlineEntries
where fbe.HDC == gl.RenderContextProvider.DeviceContextHandle
&& fbe.HRC == gl.RenderContextProvider.RenderContextHandle
&& String.Compare(fbe.FaceName, faceName, StringComparison.OrdinalIgnoreCase) == 0
&& fbe.Height == fontHeight
&& fbe.Deviation == deviation
&& fbe.Extrusion == extrusion
select fbe).ToList();
// Get the FBE or null.
var fontOutlineEntry = result.FirstOrDefault();
// If we don't have the FBE, we must create it.
if (fontOutlineEntry == null)
fontOutlineEntry = CreateFontOutlineEntry(gl, faceName, fontHeight, deviation, extrusion, FontOutlineFormat.Polygons);
// Set the list base.
gl.ListBase(fontOutlineEntry.ListBase);
// Create an array of lists for the glyphs.
var lists = text.Select(c => (byte) c).ToArray();
// Call the lists for the string.
gl.CallLists(lists.Length, lists);
gl.Flush();
// Return the glyph metrics used.
glyphMetrics = fontOutlineEntry.GlyphMetrics;
}
private FontOutlineEntry CreateFontOutlineEntry(OpenGL gl, string faceName, int height,
float deviation, float extrusion, FontOutlineFormat fontOutlineFormat)
{
// Make the OpenGL instance current.
gl.MakeCurrent();
// Create the font based on the face name.
var hFont = Win32.CreateFont(height, 0, 0, 0, Win32.FW_DONTCARE, 0, 0, 0, Win32.DEFAULT_CHARSET,
Win32.OUT_OUTLINE_PRECIS, Win32.CLIP_DEFAULT_PRECIS, Win32.CLEARTYPE_QUALITY, Win32.VARIABLE_PITCH, faceName);
// Select the font handle.
var hOldObject = Win32.SelectObject(gl.RenderContextProvider.DeviceContextHandle, hFont);
// Create the list base.
var listBase = gl.GenLists(1);
// Create space for the glyph metrics.
var glyphMetrics = new GLYPHMETRICSFLOAT[255];
// Create the font bitmaps.
bool result = Win32.wglUseFontOutlines(gl.RenderContextProvider.DeviceContextHandle, 0, 255, listBase,
deviation, extrusion, (int)fontOutlineFormat, glyphMetrics);
// Reselect the old font.
Win32.SelectObject(gl.RenderContextProvider.DeviceContextHandle, hOldObject);
// Free the font.
Win32.DeleteObject(hFont);
// Create the font bitmap entry.
var foe = new FontOutlineEntry()
{
HDC = gl.RenderContextProvider.DeviceContextHandle,
HRC = gl.RenderContextProvider.RenderContextHandle,
FaceName = faceName,
Height = height,
ListBase = listBase,
ListCount = 255,
Deviation = deviation,
Extrusion = extrusion,
FontOutlineFormat = fontOutlineFormat,
GlyphMetrics = glyphMetrics
};
// Add the font bitmap entry to the internal list.
fontOutlineEntries.Add(foe);
return foe;
}
