Texture Options
The Redshift Texture Options give you better control over texture filtering and MIP-mapping on a per-texture basis.
Redshift貼圖紋理選項為這種紋理提供了Texture Filtering（紋理過濾）和MIP-Mapping功能，這能讓用戶更好的控制紋理。
Unless absolutely necessary, it is recommended the Texture Options be left at the default settings, otherwise rendering and texture out-of-core performance can suffer.
除非絕對需要，建議保持Texture Options默認設置，否則可能導致渲染和Out-of-Core（出核）性能受影響。
In Maya, the option can be found under the Redshift tab of the 『file』 node, as detailed below:
在Maya中，可在File菜單下找到Redshift欄，如下圖所示。
Parameters參數
Filter Enable開啟過濾
Selects the filtering enable mode of the texture sampler;
用於選擇貼圖採樣過濾模式：
None (no MIP-mapping, point-sampled for 『minification』 and 『magnification』)
None無MIP-Mapping、Point-Sampled（點採樣）或者Minification（縮小） 和Magnification（放大）
Magnification (no MIP-mapping, point-sampled for 『minification』)
Magnification(無MIP-Mapping，「Minification」點採樣)
Magnification/Minification (recommended default. MIP-mapped, with full filtering)
Magnification/Minification（推薦默認設置。開啟MIP-Mapped，使用Full
Filtering）Prefer Sharp Filtering優先弱化過濾
By default Redshift will attempt to bias texture filtering to produce the sharpest results. However, for very noisy tiled textures, sometimes this can produce interference patterns. Un-checking this option will disable the sharpness biasing, producing softer results that remove these interference patterns.
在默認設置下，Redshift使用偏移紋理過濾來銳化結果。但假如條塊化的（Tiled）紋理中噪點嚴重，有可能產生幹擾條紋。不勾選該選項可關掉銳化偏移，產生更柔和的結果，從而去掉這些幹擾條紋。
Note this option only takes effect when the 『Filter Enable』 mode is set to 『Magnification/Minification』.
『Magnification/Minification』.注意，該選項僅在Filter Enable設為Magnification/Minification時有效
MIP Bias MIP偏移
Allows you to bias the MIP level, such that values less than 0 result in sharper quality, but slower texture sampling. Values greater than 0 result in blurrier lower quality, but faster texture sampling.
用於設置MIP級別的偏移量。小於0時，銳化質量高，紋理採樣計算變慢。大於0時，結果更模糊，但是紋理採樣計算較快。
Note this option only takes effect when the 『Filter Enable』 mode is set to 『Magnification/Minification』.
注意，該選項僅在Filter Enable設為Magnification/Minification時有效。
Filter Enable開啟過濾
Sometimes a texture may require special filtering treatment, where the global texture sampling mode (found under the Optimization tab) might not be adequate.
當紋理需要特殊過濾處理時，全局Texture Sampling模式（在渲染器設置的Optimization選項卡中）可能不合適。
For example, this can be the case when a texture has an alpha cut-out and the color part of the texture is not configured to take texture filtering into consideration. When this is the case, filtering and MIP-mapping will result in undesirable color bleeding artifacts that can manifest as a halo around the cut-out texture. If correcting your texture in this kind of situation is not an option, then it is recommended you change the 『Filter Enable』 property to 『Magnification』, so you still get soft, filtered results when magnifying the texture, but no filtering and thus bleeding when 『minifying』 the texture.
例如，當紋理貼圖帶Alpha剪切信息而且貼圖的顏色沒有考慮到紋理過濾時，對於這種情況，過濾或者MIP-Mapping會導致不希望出現的色溢問題，這會導致在切出的圖像周圍出現光暈。在這種情況下如果無法直接處理貼圖，則建議將Filter
Enable設定在Magnification模式。這樣，通過放大紋理貼圖，仍能可以得到柔和的過濾效果。反過來說，如果使用「Minifying」模式，即使不過濾，也會產生色溢問題。Below is an example of a poorly configured texture and a correctly configured texture:
下面的例子展示了一個糟糕的問題貼圖和一個正確的紋理貼圖：
Below are example renders showing the undesired artifact that arises from the texture being poorly configured, with the solutions. Note the images are slightly blurred here because they have been enlarged from their original rendered size to better show the halo effect present when the texture has been poorly configured and is filtered. You can also clearly see the properly configured texture on the right has no halo effect, even with default texture filtering:
下面是一些渲染出來的葉子，可以看到，錯誤的貼圖導致葉子周圍出現白邊。後面兩個解決了這一問題。可以看到，這裡圖像有些模糊。因為為了更好的展示正確與錯誤的區別。已經將它們從原始渲染大小放大了一些。而從右邊可以明顯看出，只要正確設置紋理，即採樣默認過濾方式也不會產生白邊。
Another situation when you might need to disable filtering is when a texture contains non-color information, such as rotation, which could be used to drive the anisotropy rotation of reflection. When this is the case, filtering and MIP-mapping will result in 『in-between』 values that might not make sense for the rotation texture to function properly. So, setting the 『Filter Enable』 option to 『None』 is recommended to remove any undesired artifacts due to filtering.
另一種需要關掉過濾的情況是，紋理貼圖並非用於顏色上，比如用於驅動各向異性屬性的旋轉。這時過濾和MIP-Mapping將導致亮度被平均。對於驅動旋轉的紋理而言，這種做法沒有幫助。因此，這是建議把Filter Enable選項設置為None，去除過濾造成的負擔。
MIP Bias MIP偏移
When MIP-mapping is enabled Redshift will load and sample pre-filtered multi-resolution texture data that is optimal for how large the texture appears in the render. For example, when a texture is very far away from the camera, less texture detail is required, so a lower resolution MIP level can be loaded without any loss of quality or perceived detail. Conversely, when a texture is very close to the camera, more texture detail is required, so the highest, native resolution MIP level is typically loaded. MIP-mapping is a necessary performance optimization that is commonly used in rendering.
當開啟MIP-Mapping時，Redshift將會載入並採樣經過過濾的多級解析度紋理數據。它會根據實際渲染時紋理的大小來自動調用合適的解析度。例如，一個貼圖距離攝像機很遠，不需要太多的紋理細節，這時就會載入較低解析度的MIP級別，最終渲染結果也不會損失質量和細節。相反，當一個貼圖距離攝像機非常近時，就需要更多的紋理細節，此時通常會載入最高解析度MIP級別的原始圖紋理。MIP-Mapping是一種必要的性能優化，它通常被用於渲染。
There are some situations, however, when the algorithm to select the appropriate MIP level may not produce perfectly detailed results due to a non-perfect combination of the MIP-level pre-filtering and the AA settings. In this case, setting the MIP Bias to negative values will bring forward higher resolution MIP levels and thus sharpen the texture. Or, there may be a situation when you want to purposely soften the texture, so setting the MIP Bias to positive values will bring forward lower resolution blurrier MIP levels.
也有一些情況，儘管演算法能夠選擇適當的MIP級別，但渲染效果仍然損失了細節。通常這是因為MIP-Level Pre-Filtering與AA（全局採樣）設置沒有很好匹配。此時將MIP Bias設置為負值，強迫渲染時調用更高解析度的MIP級別，這樣就可以得到更銳利的紋理。此外，如果希望讓紋理變得柔和一些，可以組MIP Bias設置一個正值，這樣一來，引擎將調用更低解析度，更模糊的MIP級別。
For example, a value of -1 will result in 2x the resolution of the MIP-level being used, while a value of -2 will result in 4x the resolution of the MIP-level, up to the maximum/native resolution of the texture. A value of 1 will result in 0.5x the resolution of the MIP-level, and a value of 2 will result in 0.25x the resolution of the MIP level being used, etc.
-1意味著紋理使用兩倍解析度MIP級別，-2意味著紋理使用四倍解析度MIP級別，最高到紋理貼圖的原始解析度。1意味著使用紋理二分之一解析度MIP級別，2意味著使用四分之一MIP級別，以此類推。
Be careful to not use too large negative values for the MIP Bias, as texturing and out-of-core performance can suffer, impacting render times.
注意不要將MIP偏移設為很大的負數，因為這樣會影響讀取紋理和出核（Out-of-Core）的性能，導致渲染時間變長。
The MIP Bias option has no effect when the 『Filter Enable』 option is not the default 『Magnification/Minification』.
如果Filter Enable沒有使用Magnification/Minification模式，MIP Bias選項不起作用。
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