Fix panels that are moving off-screen having an incorrect X coordinate applied.

This commit is contained in:
Thomas Müller 2016-12-10 11:30:22 +01:00
parent 068b413225
commit 9c4c713aa0
1 changed files with 32 additions and 20 deletions

View File

@ -190,18 +190,45 @@ private static float offsetX(float dist, float halfHeight)
return 125 + x;
}
/// <summary>
/// Update a panel's x position and multiplicative alpha based on its y position and
/// the current scroll position.
/// </summary>
/// <param name="p">The panel to be updated.</param>
/// <param name="halfHeight">Half the draw height of the carousel container.</param>
private void updatePanel(Panel p, float halfHeight)
{
float panelDrawY = p.Position.Y - Current + p.DrawHeight / 2;
float dist = Math.Abs(1f - panelDrawY / halfHeight);
// Setting the origin position serves as an additive position on top of potential
// local transformation we may want to apply (e.g. when a panel gets selected, we
// may want to smoothly transform it leftwards.)
p.OriginPosition = new Vector2(-offsetX(dist, halfHeight), 0);
// We are applying a multiplicative alpha (which is internally done by nesting an
// additional container and setting that container's alpha) such that we can
// layer transformations on top, with a similar reasoning to the previous comment.
p.SetMultiplicativeAlpha(MathHelper.Clamp(1.75f - 1.5f * dist, 0, 1));
}
protected override void Update()
{
base.Update();
// Determine which items stopped being on screen for future removal from the lifetimelist.
float drawHeight = DrawHeight;
float halfHeight = drawHeight / 2;
Lifetime.AliveItems.ForEach(delegate (Panel p)
foreach (Panel p in Lifetime.AliveItems)
{
float panelPosY = p.Position.Y;
p.IsOnScreen = panelPosY >= Current - p.DrawHeight && panelPosY <= Current + drawHeight;
});
updatePanel(p, halfHeight);
}
// Determine range of indices for items that are now definitely on screen to be added
// to the lifetimelist in the future.
int firstIndex = yPositions.BinarySearch(Current - Panel.MAX_HEIGHT);
if (firstIndex < 0) firstIndex = ~firstIndex;
int lastIndex = yPositions.BinarySearch(Current + drawHeight);
@ -210,26 +237,11 @@ protected override void Update()
Lifetime.StartIndex = firstIndex;
Lifetime.EndIndex = lastIndex;
float halfHeight = drawHeight / 2;
for (int i = firstIndex; i < lastIndex; ++i)
{
var panel = Lifetime[i];
panel.IsOnScreen = true;
float panelDrawY = panel.Position.Y - Current + panel.DrawHeight / 2;
float dist = Math.Abs(1f - panelDrawY / halfHeight);
// Setting the origin position serves as an additive position on top of potential
// local transformation we may want to apply (e.g. when a panel gets selected, we
// may want to smoothly transform it leftwards.)
panel.OriginPosition = new Vector2(-offsetX(dist, halfHeight), 0);
// We are applying a multiplicative alpha (which is internally done by nesting an
// additional container and setting that container's alpha) such that we can
// layer transformations on top, with a similar reasoning to the previous comment.
panel.SetMultiplicativeAlpha(MathHelper.Clamp(1.75f - 1.5f * dist, 0, 1));
Panel p = Lifetime[i];
p.IsOnScreen = true;
updatePanel(p, halfHeight);
}
}
}