我正在使用 XNA 开发一款太空射击游戏，并遵循多个教程来创建视差背景。到目前为止，我可以让它沿着 X 或 Y 轴移动，但不能同时沿着两个轴移动。我有一个跟随玩家的相机类，玩家移动它（而不是“世界”），因为我认为移动玩家比移动玩家周围的其他一切更容易。
到目前为止，背景跟不上玩家，也无法同时理解两个轴。我想过一个平铺引擎，但这不会让我在不同的图层上产生视差，对吗？
谁能帮我理解我需要做什么，或者推荐一个可以同时做两个轴的教程？这次我似乎无法自己找到答案。
这是我的背景类的代码：
class Background
{
// Textures to hold the two background images
Texture2D spaceBackground, starsParallax;
int backgroundWidth = 2048;
int backgroundHeight = 2048;
int parallaxWidth = 2048;
int parallaxHeight = 2048;
int backgroundWidthOffset;
int backgroundHeightOffset;
int parallaxWidthOffset;
int parallaxHeightOffset;
public int BackgroundWidthOffset
{
get { return backgroundWidthOffset; }
set
{
backgroundWidthOffset = value;
if (backgroundWidthOffset < 0)
{
backgroundWidthOffset += backgroundWidth;
}
if (backgroundWidthOffset > backgroundWidth)
{
backgroundWidthOffset -= backgroundWidth;
}
}
}
public int BackgroundHeightOffset
{
get { return backgroundHeightOffset; }
set
{
backgroundHeightOffset = value;
if (backgroundHeightOffset < 0)
{
backgroundHeightOffset += backgroundHeight;
}
if (backgroundHeightOffset > backgroundHeight)
{
backgroundHeightOffset -= backgroundHeight;
}
}
}
public int ParallaxWidthOffset
{
get { return parallaxWidthOffset; }
set
{
parallaxWidthOffset = value;
if (parallaxWidthOffset < 0)
{
parallaxWidthOffset += parallaxWidth;
}
if (parallaxWidthOffset > parallaxWidth)
{
parallaxWidthOffset -= parallaxWidth;
}
}
}
public int ParallaxHeightOffset
{
get { return parallaxHeightOffset; }
set
{
parallaxHeightOffset = value;
if (parallaxHeightOffset < 0)
{
parallaxHeightOffset += parallaxHeight;
}
if (parallaxHeightOffset > parallaxHeight)
{
parallaxHeightOffset -= parallaxHeight;
}
}
}
// Constructor when passed a Content Manager and two strings
public Background(ContentManager content,
string sBackground, string sParallax)
{
spaceBackground = content.Load<Texture2D>(sBackground);
backgroundWidth = spaceBackground.Width;
backgroundHeight = spaceBackground.Height;
starsParallax = content.Load<Texture2D>(sParallax);
parallaxWidth = starsParallax.Width;
parallaxHeight = starsParallax.Height;
}
public void Draw(SpriteBatch spriteBatch)
{
// Draw the background panel, offset by the player's location
spriteBatch.Draw(
spaceBackground,
new Rectangle(-1 * backgroundWidthOffset,
-1 * backgroundHeightOffset,
backgroundWidth,
backgroundHeight),
Color.White);
// If the right edge of the background panel will end
// within the bounds of the display, draw a second copy
// of the background at that location.
if (backgroundWidthOffset > backgroundWidth)
{
spriteBatch.Draw(
spaceBackground,
new Rectangle(
(-1 * backgroundWidthOffset) + backgroundWidth, 0,
backgroundWidth, backgroundHeight),
Color.White);
}
else //(backgroundHeightOffset > backgroundHeight - viewportHeight)
{
spriteBatch.Draw(
spaceBackground,
new Rectangle(
0, (-1 * backgroundHeightOffset) + backgroundHeight,
backgroundHeight, backgroundHeight),
Color.White);
}
// Draw the parallax star field
spriteBatch.Draw(
starsParallax,
new Rectangle(-1 * parallaxWidthOffset,
0, parallaxWidth,
parallaxHeight),
Color.SlateGray);
// if the player is past the point where the star
// field will end on the active screen we need
// to draw a second copy of it to cover the
// remaining screen area.
if (parallaxWidthOffset > parallaxWidth)
{
spriteBatch.Draw(
starsParallax,
new Rectangle(
(-1 * parallaxWidthOffset) + parallaxWidth,
0,
parallaxWidth,
parallaxHeight),
Color.White);
}
}
}
然后主游戏与玩家一起移动背景。
background.BackgroundWidthOffset -= 2;
background.ParallaxWidthOffset -= 1;
从视觉上看，背景有点跳跃，似乎随机跳过或重叠背景图块。