public static Vector2 GetContentAnchoredPositionBounded(this ScrollRect sr, Vector2 targetAnchoredPos)
{
if (sr && sr.content)
{
var contentRtx = sr.content.transform as RectTransform;
var srRtx = sr.transform as RectTransform;
Bounds contentBounds = sr.GetContentBoundsInAnotherSpace((RectTransform)sr.transform);
Bounds viewBounds = new Bounds(srRtx.rect.center, srRtx.rect.size);
bool allowHorizontal = (sr.movementType == ScrollRect.MovementType.Unrestricted) || contentBounds.size.x > viewBounds.size.x;
bool allowVertical = (sr.movementType == ScrollRect.MovementType.Unrestricted) || contentBounds.size.y > viewBounds.size.y;
Vector2 offset = sr.CalculateOffsetImpl(targetAnchoredPos - contentRtx.anchoredPosition);
targetAnchoredPos += offset;
if (!sr.horizontal || !allowHorizontal)
{
targetAnchoredPos.x = contentRtx.anchoredPosition.x;
}
if (!sr.vertical || !allowVertical)
{
targetAnchoredPos.y = contentRtx.anchoredPosition.y;
}
return(targetAnchoredPos);
}
return(Vector2.zero);
}
static Vector3 CalculateOffsetImpl(this ScrollRect sr, Vector2 delta)
{
if (sr)
{
Vector3 offset = Vector3.zero;
if (sr.movementType == ScrollRect.MovementType.Unrestricted)
{
return(offset);
}
var srRtx = sr.transform as RectTransform;
Bounds srBounds = new Bounds(srRtx.rect.center, srRtx.rect.size);
Bounds contentBounds = sr.GetContentBoundsInAnotherSpace((RectTransform)sr.transform);
bool allowHorizontal = (sr.movementType == ScrollRect.MovementType.Unrestricted) || contentBounds.size.x > srBounds.size.x;
bool allowVertical = (sr.movementType == ScrollRect.MovementType.Unrestricted) || contentBounds.size.y > srBounds.size.y;
Vector2 contentBoundsTranslatedMin = contentBounds.min;
Vector2 contentBoundsTranslatedMax = contentBounds.max;
if (sr.horizontal)
{
contentBoundsTranslatedMin.x += delta.x;
contentBoundsTranslatedMax.x += delta.x;
if (!allowHorizontal || contentBoundsTranslatedMin.x > srBounds.min.x)
{
offset.x = srBounds.min.x - contentBoundsTranslatedMin.x;
}
else if (contentBoundsTranslatedMax.x < srBounds.max.x)
{
offset.x = srBounds.max.x - contentBoundsTranslatedMax.x;
}
}
if (sr.vertical)
{
contentBoundsTranslatedMin.y += delta.y;
contentBoundsTranslatedMax.y += delta.y;
if (!allowVertical || contentBoundsTranslatedMax.y < srBounds.max.y)
{
offset.y = srBounds.max.y - contentBoundsTranslatedMax.y;
}
else if (contentBoundsTranslatedMin.y > srBounds.min.y)
{
offset.y = srBounds.min.y - contentBoundsTranslatedMin.y;
}
}
return(offset);
}
return(Vector3.zero);
}
public static Vector2 GetClosestContentAnchoredPositionBounded(this ScrollRect sr, Vector2 targetAnchoredPosA, Vector2 targetAnchoredPosB)
{
if (sr && sr.content)
{
var contentRtx = sr.content.transform as RectTransform;
var srRtx = sr.transform as RectTransform;
Bounds contentBounds = sr.GetContentBoundsInAnotherSpace((RectTransform)sr.transform);
Bounds viewBounds = new Bounds(srRtx.rect.center, srRtx.rect.size);
bool allowHorizontal = (sr.movementType == ScrollRect.MovementType.Unrestricted) || contentBounds.size.x > viewBounds.size.x;
bool allowVertical = (sr.movementType == ScrollRect.MovementType.Unrestricted) || contentBounds.size.y > viewBounds.size.y;
Vector2 offsetA = sr.CalculateOffsetImpl(targetAnchoredPosA - contentRtx.anchoredPosition);
targetAnchoredPosA += offsetA;
Vector2 offsetB = sr.CalculateOffsetImpl(targetAnchoredPosB - contentRtx.anchoredPosition);
targetAnchoredPosB += offsetB;
if (!sr.horizontal || !allowHorizontal)
{
targetAnchoredPosA.x = contentRtx.anchoredPosition.x;
targetAnchoredPosB.x = contentRtx.anchoredPosition.x;
}
if (!sr.vertical || !allowVertical)
{
targetAnchoredPosA.y = contentRtx.anchoredPosition.y;
targetAnchoredPosB.y = contentRtx.anchoredPosition.y;
}
// we want to get the closest position along A<->B
float t = 0f;
if (!Mathf.Approximately(targetAnchoredPosA.x, targetAnchoredPosB.x))
{
t = Mathf.InverseLerp(targetAnchoredPosA.x, targetAnchoredPosB.x, contentRtx.anchoredPosition.x);
}
else
{
t = Mathf.InverseLerp(targetAnchoredPosA.y, targetAnchoredPosB.y, contentRtx.anchoredPosition.y);
}
return(Vector2.Lerp(targetAnchoredPosA, targetAnchoredPosB, t));
}
return(Vector2.zero);
}
