/// <summary>
/// 切换可视区域的位置
/// </summary>
/// <param name="p">当前点位置</param>
private void ChangeVisibleRegionLocation(Point p)
{
if (currentCanvas != null && (graphSetting.CanvasScale == 1.0f))
{
int horizontalValue = (int)((p.X - validRegion.X) / horizontalScale - regionLocation.X - regionSize.Width / 2);
int verticalValue = (int)((p.Y - validRegion.Y) / verticalScale - regionLocation.Y - regionSize.Height / 2);
currentCanvas.Visible = false; // 避免闪烁
if (regionLocation.X + horizontalValue >= 0 &&
regionLocation.X + regionSize.Width + horizontalValue <= currentCanvas.AutoScrollMinSize.Width &&
currentCanvas.HorizontalScroll.Value + horizontalValue >= currentCanvas.HorizontalScroll.Minimum &&
currentCanvas.HorizontalScroll.Value + horizontalValue <= currentCanvas.HorizontalScroll.Maximum)
{
currentCanvas.HorizontalScroll.Value += horizontalValue;
}
else
{
if (horizontalValue > 0) // 向右移动可视区域
{
currentCanvas.HorizontalScroll.Value = currentCanvas.HorizontalScroll.Maximum;
}
else // 向左移动可视区域
{
currentCanvas.HorizontalScroll.Value = currentCanvas.HorizontalScroll.Minimum;
}
}
if (regionLocation.Y + verticalValue >= 0 &&
regionLocation.Y + regionSize.Height + verticalValue <= currentCanvas.AutoScrollMinSize.Height &&
currentCanvas.VerticalScroll.Value + verticalValue >= currentCanvas.VerticalScroll.Minimum &&
currentCanvas.VerticalScroll.Value + verticalValue <= currentCanvas.VerticalScroll.Maximum)
{
currentCanvas.VerticalScroll.Value += verticalValue;
}
else
{
if (verticalValue > 0) // 向下移动可视区域
{
currentCanvas.VerticalScroll.Value = currentCanvas.VerticalScroll.Maximum;
}
else // 向上移动可视区域
{
currentCanvas.VerticalScroll.Value = currentCanvas.VerticalScroll.Minimum;
}
}
selected = true;
lastMovePoint = p;
currentCanvas.Visible = true;
this.Invalidate();
currentCanvas.Invalidate();
}
}
/// <summary>
/// 切换可视区域的位置
/// </summary>
/// <param name="p">当前点位置</param>
private void ChangeVisibleRegionLocation(Point p)
{
if (currentCanvas != null)
{
int horizontalValue = p.X - regionLocation.X - (int)(regionSize.Width / 2);
int verticalValue = p.Y - regionLocation.Y - (int)(regionSize.Height / 2);
int horizontalScrollValue = (int)(horizontalValue * entireRegionSize.Width / this.Size.Width);
int verticalScrollValue = (int)(verticalValue * entireRegionSize.Height / this.Size.Height);
currentCanvas.Visible = false; // 避免闪烁
if (regionLocation.X + horizontalValue >= 0 &&
regionLocation.X + regionSize.Width + horizontalValue <= this.Size.Width &&
currentCanvas.HorizontalScroll.Value + horizontalScrollValue >= currentCanvas.HorizontalScroll.Minimum &&
currentCanvas.HorizontalScroll.Value + horizontalScrollValue <= currentCanvas.HorizontalScroll.Maximum)
{
currentCanvas.HorizontalScroll.Value += horizontalScrollValue;
}
else
{
if (horizontalValue > 0) // 向右移动可视区域
{
horizontalValue = this.Size.Width - regionSize.Width - regionLocation.X;
horizontalScrollValue = (int)(horizontalValue * entireRegionSize.Width / this.Size.Width);
currentCanvas.HorizontalScroll.Value = currentCanvas.HorizontalScroll.Maximum;
}
else // 向左移动可视区域
{
horizontalValue = -regionLocation.X;
horizontalScrollValue = (int)(horizontalValue * entireRegionSize.Width / this.Size.Width);
currentCanvas.HorizontalScroll.Value = currentCanvas.HorizontalScroll.Minimum;
}
}
if (regionLocation.Y + verticalValue >= 0 &&
regionLocation.Y + regionSize.Height + verticalValue <= this.Size.Height &&
currentCanvas.VerticalScroll.Value + verticalScrollValue >= currentCanvas.VerticalScroll.Minimum &&
currentCanvas.VerticalScroll.Value + verticalScrollValue <= currentCanvas.VerticalScroll.Maximum)
{
currentCanvas.VerticalScroll.Value += verticalScrollValue;
}
else
{
if (verticalValue > 0) // 向下移动可视区域
{
verticalValue = this.Size.Height - regionSize.Height - regionLocation.Y;
verticalScrollValue = (int)(verticalValue * entireRegionSize.Height / this.Size.Height);
currentCanvas.VerticalScroll.Value = currentCanvas.VerticalScroll.Maximum;
}
else // 向上移动可视区域
{
verticalValue = -regionLocation.Y;
verticalScrollValue = (int)(verticalValue * entireRegionSize.Height / this.Size.Height);
currentCanvas.VerticalScroll.Value = currentCanvas.VerticalScroll.Minimum;
}
}
selected = true;
regionLocation += new Size(horizontalValue, verticalValue);
lastMovePoint = p;
currentCanvas.Visible = true;
this.Invalidate();
currentCanvas.Invalidate();
}
}