// 滚动到指定下标
public void scroll(int index, float time)
{
if (mItemList.Count == 0)
{
return;
}
clampMin(ref time, 0.05f);
clamp(ref index, 0, mItemList.Count - 1);
// 设置目标值
mTargetOffsetValue = mContainerList[mDefaultFocus].getControlValue() - mItemList[index].getCurControlValue();
if (mLoop)
{
clampCycle(ref mCurOffset, 0, mMaxControlValue, mMaxControlValue, false);
clampCycle(ref mTargetOffsetValue, 0, mMaxControlValue, mMaxControlValue, false);
}
if (mLoop && abs(mTargetOffsetValue - mCurOffset) > mMaxControlValue * 0.5f)
{
// 当起始值与目标值差值超过了最大值的一半时,则以当前值为基准,调整目标值的范围
clampCycle(ref mCurOffset, -mMaxControlValue * 0.5f, mMaxControlValue * 0.5f, mMaxControlValue, false);
clampCycle(ref mTargetOffsetValue, -mMaxControlValue * 0.5f, mMaxControlValue * 0.5f, mMaxControlValue, false);
}
mScrollSpeed = (mTargetOffsetValue - mCurOffset) / time;
mState = isFloatZero(mScrollSpeed) ? SCROLL_STATE.NONE : SCROLL_STATE.SCROLL_TARGET;
mOnScrollItem?.Invoke(mItemList[index], index);
}
protected float mDragSensitive = 0.01f; // 拖动的灵敏度
public Scroll(LayoutScript script)
{
mScript = script;
mLoop = false;
mState = SCROLL_STATE.SS_NONE;
mContainerList = new List <IScrollContainer>();
mItemList = new List <IScrollItem>();
}
protected float mScrollSpeed; // 当前滚动速度
public NGUIScroll(LayoutScript script)
{
mScript = script;
mState = SCROLL_STATE.SS_NONE;
mDragDirection = DRAG_DIRECTION.DD_HORIZONTAL;
mContainerList = new List <IScrollContainer>();
mItemList = new List <IScrollItem>();
}
// 鼠标在屏幕上抬起
protected void onScreenMouseUp(Vector2 mousePos)
{
mMouseDown = false;
// 正在拖动时鼠标抬起,则开始逐渐减速到0
if (mState == SCROLL_STATE.SS_DRAGING)
{
mState = SCROLL_STATE.SS_SCROLL_TO_STOP;
}
}
// 鼠标在屏幕上抬起
protected void onScreenMouseUp(IMouseEventCollect obj, Vector2 mousePos)
{
mMouseDown = false;
// 正在拖动时鼠标抬起,则开始逐渐减速到0
if (mState == SCROLL_STATE.DRAGING)
{
mState = SCROLL_STATE.SCROLL_TO_STOP;
}
}
protected bool mMouseDown; // 鼠标是否在窗口内按下,鼠标抬起或者离开窗口都会设置为false,鼠标按下时,跟随鼠标移动,鼠标放开时,按惯性移动
public UGUIScroll(LayoutScript script)
{
mScript = script;
mState = SCROLL_STATE.NONE;
mDragDirection = DRAG_DIRECTION.HORIZONTAL;
mContainerList = new List <IScrollContainer>();
mItemList = new List <IScrollItem>();
mItemOnCenter = true;
mFocusSpeedThreshhold = 2.0f;
mDragSensitive = 1.0f;
mAttenuateFactor = 2.0f;
}
// 滚动到指定下标
public void scroll(int index, float time)
{
clamp(ref index, 0, mItemList.Count - 1);
// 设置目标值
mTargetOffsetValue = mContainerList[mDefaultFocus].getControlValue() - mItemList[index].getCurControlValue();
if (mLoop)
{
if (Mathf.Abs(mTargetOffsetValue - mCurOffsetValue) > mMaxControlValue / 2.0f)
{
clampValue(ref mTargetOffsetValue, 0.0f, mMaxControlValue, mMaxControlValue);
clampValue(ref mCurOffsetValue, 0.0f, mMaxControlValue, mMaxControlValue);
}
}
mScrollSpeed = (mTargetOffsetValue - mCurOffsetValue) / time;
if (!isFloatZero(mScrollSpeed))
{
mState = SCROLL_STATE.SS_SCROLL_TARGET;
}
}
protected void onMouseDown(Vector2 mousePos)
{
mMouseDown = true;
mState = SCROLL_STATE.SS_DRAGING;
mScrollSpeed = 0.0f;
}
public void update(float elapsedTime)
{
// 自动匀速滚动到目标点
if (mState == SCROLL_STATE.SS_SCROLL_TARGET)
{
int preSign = sign(mTargetOffsetValue - mCurOffsetValue);
mCurOffsetValue += elapsedTime * mScrollSpeed;
int curSign = sign(mTargetOffsetValue - mCurOffsetValue);
int speedSign = sign(mScrollSpeed);
if (isFloatEqual(mTargetOffsetValue, mCurOffsetValue) || preSign != curSign && preSign == speedSign)
{
mCurOffsetValue = mTargetOffsetValue;
mState = SCROLL_STATE.SS_NONE;
}
updateItem(mCurOffsetValue);
}
// 鼠标拖动
else if (mState == SCROLL_STATE.SS_DRAGING)
{
float curOffset = mContainerList[mDefaultFocus].getControlValue() - mCurOffsetValue;
if (mDragDirection == DRAG_DIRECTION.DD_HORIZONTAL)
{
scroll(curOffset + elapsedTime * mScrollSpeed);
}
else if (mDragDirection == DRAG_DIRECTION.DD_VERTICAL)
{
scroll(curOffset + elapsedTime * mScrollSpeed);
}
}
// 鼠标抬起后自动减速到停止
else if (mState == SCROLL_STATE.SS_SCROLL_TO_STOP)
{
if (!isFloatZero(mScrollSpeed))
{
mScrollSpeed = lerp(mScrollSpeed, 0.0f, elapsedTime * mAttenuateFactor, 0.1f);
float curOffset = mContainerList[mDefaultFocus].getControlValue() - mCurOffsetValue;
scroll(curOffset + elapsedTime * mScrollSpeed);
// 当速度小于一定值时才开始选择聚焦到某一项
if (mItemOnCenter)
{
if (Mathf.Abs(mScrollSpeed) < mFocusSpeedThreshhold)
{
int focusIndex = getItemIndex(curOffset, true, mLoop);
if (focusIndex < 0 || focusIndex >= mItemList.Count)
{
focusIndex = 0;
}
float focusTime = Mathf.Abs((curOffset - mItemList[focusIndex].getCurControlValue()) / mScrollSpeed);
clampMax(ref focusTime, 1.0f);
scroll(focusIndex, focusTime);
mState = SCROLL_STATE.SS_SCROLL_TARGET;
}
}
// 逐渐减速到0
else
{
if (isFloatZero(mScrollSpeed))
{
mState = SCROLL_STATE.SS_NONE;
}
}
}
// 被意外停止,则回到初始状态
else
{
if (mItemOnCenter)
{
float curOffset = mContainerList[mDefaultFocus].getControlValue() - mCurOffsetValue;
int focusIndex = getItemIndex(curOffset, true, mLoop);
scroll(focusIndex, 0.3f);
mState = SCROLL_STATE.SS_SCROLL_TARGET;
}
else
{
mState = SCROLL_STATE.SS_NONE;
}
}
}
}
public void update(float elapsedTime)
{
// 自动匀速滚动到目标点
if (mState == SCROLL_STATE.SCROLL_TARGET)
{
float preOffset = mCurOffset;
float newSpeed = sign(mTargetOffsetValue - mCurOffset) * abs(mScrollSpeed);
mCurOffset += elapsedTime * newSpeed;
if (isReachTarget(preOffset, mCurOffset, mTargetOffsetValue, newSpeed))
{
mCurOffset = mTargetOffsetValue;
mState = SCROLL_STATE.NONE;
}
updateItem(mCurOffset);
}
// 鼠标拖动
else if (mState == SCROLL_STATE.DRAGING)
{
float curOffset = mContainerList[mDefaultFocus].getControlValue() - mCurOffset;
scroll(curOffset + elapsedTime * mScrollSpeed, false);
}
// 鼠标抬起后自动减速到停止
else if (mState == SCROLL_STATE.SCROLL_TO_STOP)
{
float curControlValue = mContainerList[mDefaultFocus].getControlValue() - mCurOffset;
// 非循环模式下,当前偏移值小于0或者大于最大值时,需要回到正常的范围,偏移值越小,减速越快
bool autoClamp = !mLoop && !inRange(curControlValue, 0.0f, mMaxControlValue, true);
if (!isFloatZero(mScrollSpeed))
{
if (autoClamp)
{
float delta = 0.0f;
if (curControlValue < 0.0f)
{
delta = 1.0f - curControlValue * 10.0f;
}
else if (curControlValue > mMaxControlValue)
{
delta = 1.0f + (curControlValue - mMaxControlValue) * 10.0f;
}
mScrollSpeed = lerp(mScrollSpeed, 0.0f, elapsedTime * mAttenuateFactor * delta * delta * 200.0f, 0.1f);
}
else
{
mScrollSpeed = lerp(mScrollSpeed, 0.0f, elapsedTime * mAttenuateFactor, 0.1f);
}
curControlValue += elapsedTime * mScrollSpeed;
scroll(curControlValue, false);
// 当速度小于一定值时才开始选择聚焦到某一项
if (mItemOnCenter)
{
if (autoClamp)
{
if (isFloatZero(mScrollSpeed))
{
scrollToTarget(curControlValue, 0.1f, false);
}
}
else
{
if (abs(mScrollSpeed) < mFocusSpeedThreshhold)
{
scrollToTarget(curControlValue);
}
}
}
// 逐渐减速到0
else
{
if (isFloatZero(mScrollSpeed))
{
if (autoClamp)
{
scrollToTarget(curControlValue, 0.1f, false);
}
else
{
mState = SCROLL_STATE.NONE;
}
}
}
}
// 鼠标停止后才抬起结束拖拽
else
{
// 超出范围则回到正常范围内
if (autoClamp)
{
scrollToTarget(curControlValue, 0.1f, false);
}
else
{
if (mItemOnCenter)
{
scrollToTarget(curControlValue);
}
else
{
mState = SCROLL_STATE.NONE;
}
}
}
}
}
