33 lines
1.1 KiB
Markdown
33 lines
1.1 KiB
Markdown
|
# NiagaraClearEachFrame
|
|||
|
|
|
|||
|
|
- **功能描述：** ScriptStruct /Script/Niagara.NiagaraSpawnInfo
|
|||
|
|
- **使用位置：** USTRUCT
|
|||
|
|
- **引擎模块：** Niagara
|
|||
|
|
- **元数据类型：** bool
|
|||
|
|
- **常用程度：** 0
|
|||
|
|
|
|||
|
|
指定某结构的数据在Niagara后续每一帧不应该读取，只作为初始数据。
|
|||
|
|
|
|||
|
|
当前只用在FNiagaraSpawnInfo上，仅仅内部用。
|
|||
|
|
|
|||
|
|
## 源码例子：
|
|||
|
|
|
|||
|
|
```cpp
|
|||
|
|
/** Data controlling the spawning of particles */
|
|||
|
|
USTRUCT(BlueprintType, meta = (DisplayName = "Spawn Info", NiagaraClearEachFrame = "true"))
|
|||
|
|
struct FNiagaraSpawnInfo
|
|||
|
|
{
|
|||
|
|
}
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
## 原理：
|
|||
|
|
|
|||
|
|
```cpp
|
|||
|
|
// If the NiagaraClearEachFrame value is set on the data set, we don't bother reading it in each frame as we know that it is is invalid. However,
|
|||
|
|
// this is only used for the base data set. Other reads are potentially from events and are therefore perfectly valid.
|
|||
|
|
if (DataSetIndex == 0 && Var.GetType().GetScriptStruct() != nullptr && Var.GetType().GetScriptStruct()->GetMetaData(TEXT("NiagaraClearEachFrame")).Equals(TEXT("true"), ESearchCase::IgnoreCase))
|
|||
|
|
{
|
|||
|
|
Fmt = VariableName + TEXT("{0} = {4};\n");
|
|||
|
|
}
|
|||
|
|
```
|