# Using Unreal Engine Linear Color Even though ILIAD offers many ways to create or select colors, you might need to use Unreal Engine's default nodes and variables (To know more about variables, please read the section "[Variables](https://praxinos.coop/Documentation/Iliad/User/html/Iliad-User-Documentation/User-guide/Odyssey-Brushes/Variables/)"). This is especially true for brushes that requires a very specific color to be embedded with, such as "Red" for a blood brush : ![](data/odysseybrush-nodes-color-ue-blood-result.png) *The brush* ![](data/odysseybrush-nodes-color-ue-blood-parameters.png) *Its options in Exposed Parameters* In the example above, as we needed to always use the exact same color each time the brush gets selected, we could not use "Get Color Modifier" node (as the color can be easily changed). To make this brush, we had to create a specific variable, "**Linear Color**". ![](data/odysseybrush-nodes-color-ue-linearcolor.png) Linear Color is mandatory each time you will create a brush that requires a specific color (white for snow, red for blood, green for leaves, etc). • **Pros**: if exposed, Linear Color can be directly changed in ILIAD interface (in case you would need to proceed with subtle changes). • **Cons**: Linear Color is not directly compatible with Odyssey Color Structures, so you cannot use it directly with nodes like "Fill Block with Color". Fortunately, you can combine Linear Color variables with another default node provided by Unreal Engine : "**Break Color**". ![](data/odysseybrush-nodes-color-ue-linearcolor-break.png) Thanks to this node, you can split Linear Color into RGBA channels. From that point, you can then simply connect the Float output to ILIAD nodes such as "Make Odyssey Brush Color Into RGBAF". And, if necessary (for subtle changes), keep converting the color with other Break / Make nodes until you get the possibility to connect it to an input Odyssey Color Structure. As an example*, this is how color is managed in Blood brush Blueprint : ![](data/odysseybrush-nodes-color-ue-blood-blueprint.png) Red is broken 3 times : once into RGBA before being connected to "Fill Preserve Alpha" (now replaced by "Fill Block with Color"); twice into RGBA, then converted into HSLA - with a subtle change on Luminosity - before being connected to "Fill Preserve Alpha". The whole process allows the brush to use 3 nuances of red to give a more realistic look. Changing the red color directly into ILIAD (i.e. to make alien's greenish blood) would re-apply those 3 calculations all over again. ![](data/odysseybrush-nodes-color-ue-blood-result-alien.png) *(*Blood Brush blueprint has changed in ILIAD 0.6, but the explanation remains the same*.)