export interface BeginCountRange {
begin: number;
count: number;
}
export interface BeginEndRange {
begin: number;
end: number;
}
function endOfRange(r: BeginEndRange | BeginCountRange): number {
return 'count' in r ? r.begin + r.count : r.end;
}
function* rangeAsIterator(r: BeginEndRange | BeginCountRange): Generator<number> {
for (let i = r.begin; i < endOfRange(r); ++i) {
yield i;
}
}
* Represents a range of subresources of a single-plane texture:
* a min/max mip level and min/max array layer.
*/
export class SubresourceRange {
readonly mipRange: BeginEndRange;
readonly layerRange: BeginEndRange;
constructor(subresources: {
mipRange: BeginEndRange | BeginCountRange;
layerRange: BeginEndRange | BeginCountRange;
}) {
this.mipRange = {
begin: subresources.mipRange.begin,
end: endOfRange(subresources.mipRange),
};
this.layerRange = {
begin: subresources.layerRange.begin,
end: endOfRange(subresources.layerRange),
};
}
* Iterates over the "rectangle" of `{ level, layer }` pairs represented by the range.
*/
*each(): Generator<{ level: number; layer: number }> {
for (let level = this.mipRange.begin; level < this.mipRange.end; ++level) {
for (let layer = this.layerRange.begin; layer < this.layerRange.end; ++layer) {
yield { level, layer };
}
}
}
* Iterates over the mip levels represented by the range, each level including an iterator
* over the array layers at that level.
*/
*mipLevels(): Generator<{ level: number; layers: Generator<number> }> {
for (let level = this.mipRange.begin; level < this.mipRange.end; ++level) {
yield {
level,
layers: rangeAsIterator(this.layerRange),
};
}
}
}
