private List<BitmapFontRegion> GenerateRegions(BitmapFontFile file)
{
var regions = new List<BitmapFontRegion>();
foreach (var character in file.Chars)
{
BitmapFontRegion region = new BitmapFontRegion()
{
Character = (char)character.ID,
Rect = new Rectangle(character.X, character.Y, character.Width, character.Height),
XOffset = character.XOffset,
YOffset = character.YOffset,
XAdvance = character.XAdvance
};
regions.Add(region);
}
return regions;
}
/// <summary>
/// Regenerates vertex and UV information. (Call this after making changes to font, string, or position.)
/// Note: This is called in the constructor.
/// </summary>
public void GenerateInformation()
{
BitmapFontRegion[] regions = new BitmapFontRegion[String.Length];
verticies = new Vector2[String.Length * 6];
uvs = new Vector2[String.Length * 6];
int length = String.Length;
int vi = 0, ui = 0; // Vertex index, UV index
int dx = 0, dy = 0;
for (int i = 0; i < length; i++)
{
regions[i] = Font.GetCharacterRegion(String[i]);
if (regions[i] != null)
{
// Calculate verticies
var VTopLeft = new Vector2(dx + regions[i].XOffset, dy + regions[i].YOffset);
var VTopRight = VTopLeft + new Vector2(regions[i].Rect.Width, 0);
var VBottomLeft = VTopLeft + new Vector2(0, regions[i].Rect.Height);
var VBottomRight = VTopLeft + new Vector2(regions[i].Rect.Width, regions[i].Rect.Height);
// Add verticies to array (TL,TR,BL,TR,BL,BR)
verticies[vi++] = VTopLeft;
verticies[vi++] = VTopRight;
verticies[vi++] = VBottomLeft;
verticies[vi++] = VTopRight;
verticies[vi++] = VBottomLeft;
verticies[vi++] = VBottomRight;
// Calculate and add UVs
Vector2 uvCoefficient = new Vector2(1 / Font.TextureSize.X, 1 / Font.TextureSize.Y);
var UTopLeft = new Vector2(regions[i].Rect.X * uvCoefficient.X, regions[i].Rect.Y * uvCoefficient.Y);
var UTopRight = UTopLeft + new Vector2(regions[i].Rect.Width * uvCoefficient.X, 0);
var UBottomLeft = UTopLeft + new Vector2(0, regions[i].Rect.Height * uvCoefficient.Y);
var UBottomRight = UTopLeft + new Vector2(regions[i].Rect.Width * uvCoefficient.X, regions[i].Rect.Height * uvCoefficient.Y);
// Add UVs to array (TL,TR,BL,TR,BL,BR)
uvs[ui++] = UTopLeft;
uvs[ui++] = UTopRight;
uvs[ui++] = UBottomLeft;
uvs[ui++] = UTopRight;
uvs[ui++] = UBottomLeft;
uvs[ui++] = UBottomRight;
dx += regions[i].XAdvance;
}
if (String[i] == '\n')
{
dy += Font.LineHeight;
dx = 0;
}
}
GL.BindVertexArray(VAO);
GL.BindBuffer(BufferTarget.ArrayBuffer, VBO);
GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)(BlittableValueType.StrideOf(verticies) * verticies.Length), verticies, BufferUsageHint.StaticDraw);
GL.EnableVertexAttribArray(0);
GL.VertexAttribPointer(0, 2, VertexAttribPointerType.Float, false, OpenTK.BlittableValueType.StrideOf(verticies), 0);
GL.BindBuffer(BufferTarget.ArrayBuffer, UBO);
GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)(BlittableValueType.StrideOf(uvs) * uvs.Length), uvs, BufferUsageHint.StaticDraw);
GL.EnableVertexAttribArray(1);
GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, OpenTK.BlittableValueType.StrideOf(uvs), 0);
}
