SpriteBatch 绘制调用是否被 XNA 剔除？
我对 XNA 有一个非常微妙的问题，特别是 SpriteBatch。 在我的游戏中，我有一个相机类。它可以平移视图（显然），也可以放大和缩小。 当我调用 spritebatch 实例的“Begin”函数（最后一个参数）时，我将相机应用于场景。
问题：当相机 Zoomfactor 大于 1.0f 时，spritebatch 停止绘制。 我尝试调试我的场景，但找不到出错的地方。
我尝试使用“Matrix.CreateScale(2.0f);”进行渲染作为“开始”的最后一个参数。 所有其他参数均为 null，第一个参数为“SpriteSortMode.Immediate”，因此没有自定义着色器或其他参数。 但SpriteBatch还是不想画。
然后我尝试只调用“DrawString”，而 DrawString 在提供的比例（2.0f）下完美地工作。
然而，通过大量的试验和错误，我发现将 ScaleMatrix 与“Matrix.CreateTranslation(0, 0, -1)”相乘会以某种方式将“安全”值更改为 1.1f。 因此所有 1.1f 以下的 Scale 值都有效。对于上述所有内容，SpriteBatch 在正常的“Draw”调用中不会渲染单个像素。 （DrawString 仍然不受影响并且工作）。
为什么会发生这种情况？ 我没有设置任何视口或其他矩阵。 在我看来，这可能是某种奇怪的近/远剪切。 但我通常只知道 3D 东西中的那些参数。
有什么不清楚的请追问！
I have a very subtle problem with XNA, specifically the SpriteBatch.
In my game I have a Camera class. It can Translate the view (obviously) and also zoom in and out.
I apply the Camera to the scene when I call the "Begin" function of my spritebatch instance (the last parameter).
The Problem: When the cameras Zoomfactor is bigger than 1.0f, the spritebatch stops drawing.
I tried to debug my scene but I couldn't find the point where it goes wrong.
I tried to just render with "Matrix.CreateScale(2.0f);" as the last parameter for "Begin".
All other parameters were null and the first "SpriteSortMode.Immediate", so no custom shader or something.
But SpriteBatch still didn't want to draw.
Then I tried to only call "DrawString" and DrawString worked flawlessly with the provided scale (2.0f).
However, through a lot of trial and error, I found out that also multiplying the ScaleMatrix with "Matrix.CreateTranslation(0, 0, -1)" somehow changed the "safe" value to 1.1f.
So all Scale values up to 1.1f worked. For everything above SpriteBatch does not render a single pixel in normal "Draw" calls. (DrawString still unaffected and working).
Why is this happening?
I did not setup any viewport or other matrices.
It appears to me that this could be some kind of strange Near/Farclipping.
But I usually only know those parameters from 3d stuff.
If anything is unclear please ask!
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这是近/远剪裁。
您绘制的所有内容都会转换为投影空间，然后在投影空间中进行光栅化。该空间从屏幕左下角的 (-1,-1) 到右上角的 (1,1)。但这只是 (X,Y) 坐标。在 Z 坐标中，它从 0 到 1（从前到后）。该体积之外的任何内容都会被剪掉。 （参考文献：1，2，3。）
当您在 3D 中工作时，您使用的投影矩阵将压缩 Z 坐标，以便近平面在投影空间中落在 0 处，而远平面在投影空间中落在 1 处。
在 2D 中工作时，您通常会使用
Matrix.CreateOrthographic，它具有执行完全相同操作的近平面和远平面参数。只是SpriteBatch指定了自己的矩阵，并将近平面和远平面保留为 0 和 1。事实上，
SpriteBatch中精灵的顶点确实有一个 Z-坐标，尽管通常不使用它。它由layerDepth参数指定。因此，如果您设置的图层深度大于 0.5，然后放大 2，Z 坐标将超出 0 到 1 的有效范围，并且不会被渲染。（文档说 0 到 1 是有效范围，但没有指定应用变换矩阵时会发生什么。）
解决方案非常简单：不要缩放 Z 坐标。使用如下缩放矩阵：
It is near/far clipping.
Everything you draw is transformed into and then rasterised in projection space. That space runs from (-1,-1) at the bottom left of the screen, to (1,1) at the top right. But that's just the (X,Y) coordinates. In Z coordinates it goes from 0 to 1 (front to back). Anything outside this volume is clipped. (References: 1, 2, 3.)
When you're working in 3D, the projection matrix you use will compress the Z coordinates down so that the near plane lands at 0 in projection space, and the far plane lands at 1.
When working in 2D you'd normally use
Matrix.CreateOrthographic, which has near and far plane parameters that do exactly the same thing. It's just thatSpriteBatchspecifies its own matrix and leaves the near and far planes at 0 and 1.The vertices of sprites in a
SpriteBatchdo, in fact, have a Z-coordinate, even though it's not normally used. It is specified by thelayerDepthparameter. So if you set a layer depth greater than 0.5, and then scale up by 2, the Z-coordinate will be outside the valid range of 0 to 1 and won't get rendered.(The documentation says that 0 to 1 is the valid range, but does not specify what happens when you apply a transformation matrix.)
The solution is pretty simple: Don't scale your Z-coordinate. Use a scaling matrix like: