/// <summary>
/// Evaluate the range of tracking handles which a view texture overlaps with.
/// </summary>
/// <param name="texture">The texture to get handles for</param>
/// <param name="callback">
/// A function to be called with the base index of the range of handles for the given texture, and the number of handles it covers.
/// This can be called for multiple disjoint ranges, if required.
/// </param>
private void EvaluateRelevantHandles(Texture texture, HandlesCallbackDelegate callback)
{
if (texture == Storage || !(_hasMipViews || _hasLayerViews))
{
callback(0, _handles.Length);
return;
}
EvaluateRelevantHandles(texture.FirstLayer, texture.FirstLevel, texture.Info.GetSlices(), texture.Info.Levels, callback);
}
/// <summary>
/// Evaluate the range of tracking handles which a view texture overlaps with,
/// using the view's position and slice/level counts.
/// </summary>
/// <param name="firstLayer">The first layer of the texture</param>
/// <param name="firstLevel">The first level of the texture</param>
/// <param name="slices">The slice count of the texture</param>
/// <param name="levels">The level count of the texture</param>
/// <param name="callback">
/// A function to be called with the base index of the range of handles for the given texture, and the number of handles it covers.
/// This can be called for multiple disjoint ranges, if required.
/// </param>
private void EvaluateRelevantHandles(int firstLayer, int firstLevel, int slices, int levels, HandlesCallbackDelegate callback)
{
int targetLayerHandles = _hasLayerViews ? slices : 1;
int targetLevelHandles = _hasMipViews ? levels : 1;
if (_is3D)
{
// Future mip levels come after all layers of the last mip level. Each mipmap has less layers (depth) than the last.
if (!_hasLayerViews)
{
// When there are no layer views, the mips are at a consistent offset.
callback(firstLevel, targetLevelHandles);
}
else
{
(int levelIndex, int layerCount) = Get3DLevelRange(firstLevel);
if (levels > 1 && slices < _layers)
{
// The given texture only covers some of the depth of multiple mips. (a "depth slice")
// Callback with each mip's range separately.
// Can assume that the group is fully subdivided (both slices and levels > 1 for storage)
while (levels-- > 1)
{
callback(firstLayer + levelIndex, slices);
levelIndex += layerCount;
layerCount = Math.Max(layerCount >> 1, 1);
slices = Math.Max(layerCount >> 1, 1);
}
}
else
{
int totalSize = Math.Min(layerCount, slices);
while (levels-- > 1)
{
layerCount = Math.Max(layerCount >> 1, 1);
totalSize += layerCount;
}
callback(firstLayer + levelIndex, totalSize);
}
}
}
else
{
// Future layers come after all mipmaps of the last.
int levelHandles = _hasMipViews ? _levels : 1;
if (slices > 1 && levels < _levels)
{
// The given texture only covers some of the mipmaps of multiple slices. (a "mip slice")
// Callback with each layer's range separately.
// Can assume that the group is fully subdivided (both slices and levels > 1 for storage)
for (int i = 0; i < slices; i++)
{
callback(firstLevel + (firstLayer + i) * levelHandles, targetLevelHandles, true);
}
}
else
{
callback(firstLevel + firstLayer * levelHandles, targetLevelHandles + (targetLayerHandles - 1) * levelHandles);
}
}
}