private void BeginUpdate()
{
if (_slice == null)
{
_slice = new float[_d];
}
GL.GetInteger(GetPName.TextureBinding2D, out _lastTex);
Heightmap.Activate();
}
private void UpdateRows(int startY, int size)
{
Heightmap.Activate();
for (var i2 = 0; i2 < size; i2++) // foreach row to be updated
{
var i = startY + i2;
var yt = i & _n; // row in texture
for (var j = 0; j < _d; j++)
{
_slice[j] = GeneratePixelAt2(j, yt);
}
GL.TexSubImage2D(TextureTarget.Texture2D, 0, 0, yt, _d, 1, PixelFormat.Luminance,
PixelType.Float, _slice);
}
}
private void UpdateColumns(int startX, int size)
{
Heightmap.Activate();
for (var i2 = 0; i2 < size; i2++)
{
var i = startX + i2;
var xt = i & _n;
for (var j = 0; j < _d; j++)
{
_slice[j] = GeneratePixelAt2(xt, j);
}
GL.TexSubImage2D(TextureTarget.Texture2D, 0, xt, 0, 1, _d, PixelFormat.Luminance,
PixelType.Float, _slice);
}
}