KERNELS: PMC

The PMC Kernel is a custom mutating unbiased kernel designed specifically for GPU rendering. Rendering with PMC creates physically accurate lighting and caustic effects and is generally produces the highest quality result but can also take the most time to render depending on the scene. Below we will explain the options specific to the PMC kernel. All other options are explained in Directlighting and Pathtracing. You can look at those sections as needed.

内核：PMC

PMC内核是专门为GPU渲染设计的自定义突变无偏内核。 使用PMC进行渲染会产生物理上精确的照明和焦散效果，通常会产生最高质量的结果，但根据场景的不同，渲染时间也可能最多。 下面我们将解释特定于PMC内核的选项。 所有其他选项在Directlighting和Pathtracing中进行了说明。 您可以根据需要查看这些部分。

EXPLORATION strength:

Specifies how long the kernel investigates good paths before it tries to find a new path. Low values can create a noisy image while larger values can create a splotchy image.

勘探强度：

指定内核在尝试寻找新路径之前调查好路径的时间。 较低的值可能会产生噪点图像，而较大的值可能会造成斑点图像。

dIrect lIght Importance:

Causes the kernel to prioritize ray tracing paths with indirect light. For example, imagine sunlight through a window that creates a bright spot on the floor. When direct light importance is set to a value of 1, the kernel will sample this area more and reduce noise around the bright spot. If the direct light importance is reduced, the PMC kernel reduces its efforts to sample that bright area and focuses more on problematic areas that may be harder to render such as areas with more indirect lighting.

直接照明重要性：

使内核优先考虑间接光的光线跟踪路径。例如，假设阳光透过窗户在地板上产生亮点。当直接光照重要性设置为1时，内核将对该区域进行更多采样，并减少亮点周围的噪波。如果降低了直接光的重要性，则PMC内核会减少对明亮区域进行采样的工作，而将更多精力放在可能难以渲染的问题区域上，例如具有更多间接照明的区域。

max. rejects:

Controls the “bias” of the render. By reducing the value, the result will be more biased, but the render time will be shorter. In rendering terminology biased renders introduce slight blurring and other less physically accurate computational techniques in order to reduce render time. In the picture on the left below, the quality is lower than the other and is not physically accurate. But render time is faster than the other. This setting should be done entirely considering quality/speed ratio.

最大拒绝次数：

控制渲染的“偏差”。通过减小该值，结果将有更大的偏差，但渲染时间将更短。在渲染术语中，有偏差的渲染会引入轻微的模糊和其他物理精度较差的计算技术，以减少渲染时间。在左下方的图片中，画质低于其他画质，物理上不准确。但是渲染时间比另一个要快。设置时应完全考虑质量/速度比。

parallellIsm:

Controls how many samples are calculated in parallel. Smaller values require less memory to store the samples state but may cause the render to be a bit slower. High values require more memory but can reduce render time. The change in performance depends on the scene and the GPU architecture. Similar to parallel samples in Directlighting or Pathtracing. If you have a lot of Vram, be sure to use this option.

平衡采样：

控制并行计算多少个采样。 较小的值需要较少的内存来存储采样状态，但可能会导致渲染速度变慢。 较高的值需要更多的内存，但可以减少渲染时间。 性能的变化取决于场景和GPU架构。 与Directlighting或Pathtracing中的并行采样相似。 如果您有很多Vram，请确保使用此选项。

WORK CHUNK SIZE:

The number of work blocks (of 512K samples each) done per kernel run. Increasing this value increases the memory requirement on the system but does not affect memory usage and may increase render speed.

工作块尺寸：

每次内核运行完成的工作块数（每个为512K采样）。 增大此值会增加系统上的内存要求，但不会影响内存使用率，并且可能会提高渲染速度。