public void filter(Filter kind, float param = -1f)
{
var p = new Color[texture.Width * texture.Height];
texture.GetData(p);
switch (kind)
{
case Filter.THRESHOLD:
if (param < 0f || param > 1f)
{
param = 0.5f;
}
p = p.AsParallel().AsOrdered()
.Select(c => (grey: (int)((0.3 * c.R) + (0.59 * c.G) + (0.11 * c.B)), c.A))
.Select(t => (grey: t.grey / 255.0 < param ? 255 : 0, t.A))
.Select(t => Color.FromNonPremultiplied(t.grey, t.grey, t.grey, t.A)).ToArray();
break;
case Filter.GRAY:
p = p.AsParallel().AsOrdered()
.Select(c => (grey: (int)((0.3 * c.R) + (0.59 * c.G) + (0.11 * c.B)), c.A))
.Select(t => Color.FromNonPremultiplied(t.grey, t.grey, t.grey, t.A)).ToArray();
break;
case Filter.OPAQUE:
p = p.AsParallel().AsOrdered().Select(c => Color.FromNonPremultiplied(c.R, c.G, c.B, 255))
.ToArray();
break;
case Filter.INVERT:
p = p.AsParallel().AsOrdered()
.Select(c => Color.FromNonPremultiplied(255 - c.R, 255 - c.G, 255 - c.B, c.A)).ToArray();
break;
case Filter.POSTERIZE:
if (param < 2f)
{
param = 2f;
}
if (param > 255f)
{
param = 255f;
}
p = p.AsParallel().AsOrdered()
.Select(c => Color.FromNonPremultiplied((int)Math.Min(c.R, param), (int)Math.Min(c.G, param), (int)Math.Min(c.B, param), c.A)).ToArray();
break;
case Filter.BLUR:
case Filter.ERODE:
case Filter.DILATE:
break;
}
texture.SetData(p);
}