public void DrawString(float x, float y, string text)
{
GL.ActiveTexture(TextureUnit.Texture0);
shader.Activate();
GL.PushAttrib(AttribMask.AllAttribBits);
GL.Disable(EnableCap.DepthTest);
GL.Enable(EnableCap.AlphaTest);
GL.AlphaFunc(AlphaFunction.Always, 0.0f);
GL.Enable(EnableCap.Blend);
GL.BlendFunc(BlendingFactorSrc.SrcAlpha, BlendingFactorDest.OneMinusSrcAlpha);
GL.Uniform1(scaleXLoc, scaleX);
GL.Uniform1(scaleYLoc, scaleY);
for (int i = textColors.Length - 1; i >= 0; i--)
{
float mx = x + (i * 2.0f);
float my = y + (i * 2.0f);
GL.Uniform4(textColorLoc, textColors[i]);
GL.Uniform1(textPosYLoc, my);
float cx = mx;
for (int j = 0; j < text.Length; j++)
{
char c = text[j];
if (c == '\n' || (c == '\r' && text[j + 1] == '\n'))
{
cx = mx;
my += charHeight;
GL.Uniform1(textPosYLoc, my);
if (c == '\r' && text[j + 1] == '\n')
{
j++;
}
continue;
}
GL.Uniform1(textPosXLoc, cx);
if (!characters.ContainsKey(c))
{
continue;
}
FontCharacter fontChar = characters[c];
if (c != ' ')
{
if (!vaoWidthMap.ContainsKey(fontChar.Width))
{
continue;
}
int vaoHandle = vaoWidthMap[fontChar.Width];
GL.BindTexture(TextureTarget.Texture2D, fontChar.TextureHandle);
GL.BindVertexArray(vaoHandle);
GL.DrawArrays(PrimitiveType.Triangles, 0, 6);
GL.BindVertexArray(0);
}
cx += fontChar.Width;
}
}
GL.PopAttrib();
GL.UseProgram(0);
}
private void Load(FontFamily family)
{
SetScreenSize(640, 480);
System.Drawing.Font font = new System.Drawing.Font(family, size, FontStyle.Bold, GraphicsUnit.Pixel);
charHeight = (float)NextPowerOfTwo((double)font.Size);
for (char c = startChar; c < endChar; c++)
{
SizeF charSize;
using (Graphics g = Graphics.FromImage(new Bitmap(1, 1)))
{
g.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;
charSize = g.MeasureString(c.ToString(), font, 256, StringFormat.GenericTypographic);
if (charSize.Width == 0)
{
charSize = g.MeasureString(c.ToString(), font);
}
}
int charTextureWidth = (int)NextPowerOfTwo(charSize.Width);
Bitmap charTextureImage = new Bitmap(charTextureWidth, (int)charHeight);
using (Graphics g = Graphics.FromImage(charTextureImage))
{
g.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;
g.DrawString(c.ToString(), font, Brushes.White, PointF.Empty, StringFormat.GenericTypographic);
}
//charTextureImage.Save(@"C:\Temp\glsl\" + ((int)c).ToString() + ".png");
FontCharacter fontChar = new FontCharacter((float)Math.Round(charSize.Width, 1), charTextureImage);
if (!vaoWidthMap.ContainsKey(fontChar.Width))
{
float u1 = (float)fontChar.Width * (1.0f / (float)charTextureWidth);
float v1 = (float)font.Height * (1.0f / charHeight);
CharacterVertex[] vertices = new CharacterVertex[6]
{
new CharacterVertex(0.0f, charHeight, 0.0f, v1),
new CharacterVertex(fontChar.Width, 0.0f, u1, 0.0f),
new CharacterVertex(0.0f, 0.0f, 0.0f, 0.0f),
new CharacterVertex(fontChar.Width, charHeight, u1, v1),
new CharacterVertex(fontChar.Width, 0.0f, u1, 0.0f),
new CharacterVertex(0.0f, charHeight, 0.0f, v1),
};
int vaoHandle = GL.GenVertexArray();
GL.BindVertexArray(vaoHandle);
int bufferHandle = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ArrayBuffer, bufferHandle);
GL.BufferData <CharacterVertex>(BufferTarget.ArrayBuffer, new IntPtr(CharacterVertex.StructSize * vertices.Length), vertices, BufferUsageHint.StaticDraw);
GL.EnableVertexAttribArray(0);
GL.EnableVertexAttribArray(1);
GL.VertexAttribPointer(0, 2, VertexAttribPointerType.Float, false, CharacterVertex.StructSize, 0);
GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, CharacterVertex.StructSize, Marshal.OffsetOf(typeof(CharacterVertex), "U"));
GL.BindVertexArray(0);
usedArrayBuffers.Add(bufferHandle);
vaoWidthMap.Add(fontChar.Width, vaoHandle);
}
characters.Add(c, fontChar);
}
}